Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * planner.c
4 : : * The query optimizer external interface.
5 : : *
6 : : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
7 : : * Portions Copyright (c) 1994, Regents of the University of California
8 : : *
9 : : *
10 : : * IDENTIFICATION
11 : : * src/backend/optimizer/plan/planner.c
12 : : *
13 : : *-------------------------------------------------------------------------
14 : : */
15 : :
16 : : #include "postgres.h"
17 : :
18 : : #include <limits.h>
19 : : #include <math.h>
20 : :
21 : : #include "access/genam.h"
22 : : #include "access/parallel.h"
23 : : #include "access/sysattr.h"
24 : : #include "access/table.h"
25 : : #include "catalog/pg_aggregate.h"
26 : : #include "catalog/pg_inherits.h"
27 : : #include "catalog/pg_proc.h"
28 : : #include "catalog/pg_type.h"
29 : : #include "executor/executor.h"
30 : : #include "foreign/fdwapi.h"
31 : : #include "jit/jit.h"
32 : : #include "lib/bipartite_match.h"
33 : : #include "lib/knapsack.h"
34 : : #include "miscadmin.h"
35 : : #include "nodes/makefuncs.h"
36 : : #include "nodes/nodeFuncs.h"
37 : : #ifdef OPTIMIZER_DEBUG
38 : : #include "nodes/print.h"
39 : : #endif
40 : : #include "nodes/supportnodes.h"
41 : : #include "optimizer/appendinfo.h"
42 : : #include "optimizer/clauses.h"
43 : : #include "optimizer/cost.h"
44 : : #include "optimizer/optimizer.h"
45 : : #include "optimizer/paramassign.h"
46 : : #include "optimizer/pathnode.h"
47 : : #include "optimizer/paths.h"
48 : : #include "optimizer/plancat.h"
49 : : #include "optimizer/planmain.h"
50 : : #include "optimizer/planner.h"
51 : : #include "optimizer/prep.h"
52 : : #include "optimizer/subselect.h"
53 : : #include "optimizer/tlist.h"
54 : : #include "parser/analyze.h"
55 : : #include "parser/parse_agg.h"
56 : : #include "parser/parse_clause.h"
57 : : #include "parser/parse_relation.h"
58 : : #include "parser/parsetree.h"
59 : : #include "partitioning/partdesc.h"
60 : : #include "rewrite/rewriteManip.h"
61 : : #include "utils/acl.h"
62 : : #include "utils/backend_status.h"
63 : : #include "utils/lsyscache.h"
64 : : #include "utils/rel.h"
65 : : #include "utils/selfuncs.h"
66 : :
67 : : /* GUC parameters */
68 : : double cursor_tuple_fraction = DEFAULT_CURSOR_TUPLE_FRACTION;
69 : : int debug_parallel_query = DEBUG_PARALLEL_OFF;
70 : : bool parallel_leader_participation = true;
71 : : bool enable_distinct_reordering = true;
72 : :
73 : : /* Hook for plugins to get control in planner() */
74 : : planner_hook_type planner_hook = NULL;
75 : :
76 : : /* Hook for plugins to get control after PlannerGlobal is initialized */
77 : : planner_setup_hook_type planner_setup_hook = NULL;
78 : :
79 : : /* Hook for plugins to get control before PlannerGlobal is discarded */
80 : : planner_shutdown_hook_type planner_shutdown_hook = NULL;
81 : :
82 : : /* Hook for plugins to get control when grouping_planner() plans upper rels */
83 : : create_upper_paths_hook_type create_upper_paths_hook = NULL;
84 : :
85 : :
86 : : /* Expression kind codes for preprocess_expression */
87 : : #define EXPRKIND_QUAL 0
88 : : #define EXPRKIND_TARGET 1
89 : : #define EXPRKIND_RTFUNC 2
90 : : #define EXPRKIND_RTFUNC_LATERAL 3
91 : : #define EXPRKIND_VALUES 4
92 : : #define EXPRKIND_VALUES_LATERAL 5
93 : : #define EXPRKIND_LIMIT 6
94 : : #define EXPRKIND_APPINFO 7
95 : : #define EXPRKIND_PHV 8
96 : : #define EXPRKIND_TABLESAMPLE 9
97 : : #define EXPRKIND_ARBITER_ELEM 10
98 : : #define EXPRKIND_TABLEFUNC 11
99 : : #define EXPRKIND_TABLEFUNC_LATERAL 12
100 : : #define EXPRKIND_GROUPEXPR 13
101 : :
102 : : /*
103 : : * Data specific to grouping sets
104 : : */
105 : : typedef struct
106 : : {
107 : : List *rollups;
108 : : List *hash_sets_idx;
109 : : double dNumHashGroups;
110 : : bool any_hashable;
111 : : Bitmapset *unsortable_refs;
112 : : Bitmapset *unhashable_refs;
113 : : List *unsortable_sets;
114 : : int *tleref_to_colnum_map;
115 : : } grouping_sets_data;
116 : :
117 : : /*
118 : : * Temporary structure for use during WindowClause reordering in order to be
119 : : * able to sort WindowClauses on partitioning/ordering prefix.
120 : : */
121 : : typedef struct
122 : : {
123 : : WindowClause *wc;
124 : : List *uniqueOrder; /* A List of unique ordering/partitioning
125 : : * clauses per Window */
126 : : } WindowClauseSortData;
127 : :
128 : : /* Passthrough data for standard_qp_callback */
129 : : typedef struct
130 : : {
131 : : List *activeWindows; /* active windows, if any */
132 : : grouping_sets_data *gset_data; /* grouping sets data, if any */
133 : : SetOperationStmt *setop; /* parent set operation or NULL if not a
134 : : * subquery belonging to a set operation */
135 : : } standard_qp_extra;
136 : :
137 : : /* Local functions */
138 : : static Node *preprocess_expression(PlannerInfo *root, Node *expr, int kind);
139 : : static void preprocess_qual_conditions(PlannerInfo *root, Node *jtnode);
140 : : static void grouping_planner(PlannerInfo *root, double tuple_fraction,
141 : : SetOperationStmt *setops);
142 : : static grouping_sets_data *preprocess_grouping_sets(PlannerInfo *root);
143 : : static List *remap_to_groupclause_idx(List *groupClause, List *gsets,
144 : : int *tleref_to_colnum_map);
145 : : static void preprocess_rowmarks(PlannerInfo *root);
146 : : static double preprocess_limit(PlannerInfo *root,
147 : : double tuple_fraction,
148 : : int64 *offset_est, int64 *count_est);
149 : : static List *preprocess_groupclause(PlannerInfo *root, List *force);
150 : : static List *extract_rollup_sets(List *groupingSets);
151 : : static List *reorder_grouping_sets(List *groupingSets, List *sortclause);
152 : : static void standard_qp_callback(PlannerInfo *root, void *extra);
153 : : static double get_number_of_groups(PlannerInfo *root,
154 : : double path_rows,
155 : : grouping_sets_data *gd,
156 : : List *target_list);
157 : : static RelOptInfo *create_grouping_paths(PlannerInfo *root,
158 : : RelOptInfo *input_rel,
159 : : PathTarget *target,
160 : : bool target_parallel_safe,
161 : : grouping_sets_data *gd);
162 : : static bool is_degenerate_grouping(PlannerInfo *root);
163 : : static void create_degenerate_grouping_paths(PlannerInfo *root,
164 : : RelOptInfo *input_rel,
165 : : RelOptInfo *grouped_rel);
166 : : static RelOptInfo *make_grouping_rel(PlannerInfo *root, RelOptInfo *input_rel,
167 : : PathTarget *target, bool target_parallel_safe,
168 : : Node *havingQual);
169 : : static void create_ordinary_grouping_paths(PlannerInfo *root,
170 : : RelOptInfo *input_rel,
171 : : RelOptInfo *grouped_rel,
172 : : const AggClauseCosts *agg_costs,
173 : : grouping_sets_data *gd,
174 : : GroupPathExtraData *extra,
175 : : RelOptInfo **partially_grouped_rel_p);
176 : : static void consider_groupingsets_paths(PlannerInfo *root,
177 : : RelOptInfo *grouped_rel,
178 : : Path *path,
179 : : bool is_sorted,
180 : : bool can_hash,
181 : : grouping_sets_data *gd,
182 : : const AggClauseCosts *agg_costs,
183 : : double dNumGroups);
184 : : static RelOptInfo *create_window_paths(PlannerInfo *root,
185 : : RelOptInfo *input_rel,
186 : : PathTarget *input_target,
187 : : PathTarget *output_target,
188 : : bool output_target_parallel_safe,
189 : : WindowFuncLists *wflists,
190 : : List *activeWindows);
191 : : static void create_one_window_path(PlannerInfo *root,
192 : : RelOptInfo *window_rel,
193 : : Path *path,
194 : : PathTarget *input_target,
195 : : PathTarget *output_target,
196 : : WindowFuncLists *wflists,
197 : : List *activeWindows);
198 : : static RelOptInfo *create_distinct_paths(PlannerInfo *root,
199 : : RelOptInfo *input_rel,
200 : : PathTarget *target);
201 : : static void create_partial_distinct_paths(PlannerInfo *root,
202 : : RelOptInfo *input_rel,
203 : : RelOptInfo *final_distinct_rel,
204 : : PathTarget *target);
205 : : static RelOptInfo *create_final_distinct_paths(PlannerInfo *root,
206 : : RelOptInfo *input_rel,
207 : : RelOptInfo *distinct_rel);
208 : : static List *get_useful_pathkeys_for_distinct(PlannerInfo *root,
209 : : List *needed_pathkeys,
210 : : List *path_pathkeys);
211 : : static RelOptInfo *create_ordered_paths(PlannerInfo *root,
212 : : RelOptInfo *input_rel,
213 : : PathTarget *target,
214 : : bool target_parallel_safe,
215 : : double limit_tuples);
216 : : static PathTarget *make_group_input_target(PlannerInfo *root,
217 : : PathTarget *final_target);
218 : : static PathTarget *make_partial_grouping_target(PlannerInfo *root,
219 : : PathTarget *grouping_target,
220 : : Node *havingQual);
221 : : static List *postprocess_setop_tlist(List *new_tlist, List *orig_tlist);
222 : : static void optimize_window_clauses(PlannerInfo *root,
223 : : WindowFuncLists *wflists);
224 : : static List *select_active_windows(PlannerInfo *root, WindowFuncLists *wflists);
225 : : static void name_active_windows(List *activeWindows);
226 : : static PathTarget *make_window_input_target(PlannerInfo *root,
227 : : PathTarget *final_target,
228 : : List *activeWindows);
229 : : static List *make_pathkeys_for_window(PlannerInfo *root, WindowClause *wc,
230 : : List *tlist);
231 : : static PathTarget *make_sort_input_target(PlannerInfo *root,
232 : : PathTarget *final_target,
233 : : bool *have_postponed_srfs);
234 : : static void adjust_paths_for_srfs(PlannerInfo *root, RelOptInfo *rel,
235 : : List *targets, List *targets_contain_srfs);
236 : : static void add_paths_to_grouping_rel(PlannerInfo *root, RelOptInfo *input_rel,
237 : : RelOptInfo *grouped_rel,
238 : : RelOptInfo *partially_grouped_rel,
239 : : const AggClauseCosts *agg_costs,
240 : : grouping_sets_data *gd,
241 : : GroupPathExtraData *extra);
242 : : static RelOptInfo *create_partial_grouping_paths(PlannerInfo *root,
243 : : RelOptInfo *grouped_rel,
244 : : RelOptInfo *input_rel,
245 : : grouping_sets_data *gd,
246 : : GroupPathExtraData *extra,
247 : : bool force_rel_creation);
248 : : static Path *make_ordered_path(PlannerInfo *root,
249 : : RelOptInfo *rel,
250 : : Path *path,
251 : : Path *cheapest_path,
252 : : List *pathkeys,
253 : : double limit_tuples);
254 : : static void gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel);
255 : : static bool can_partial_agg(PlannerInfo *root);
256 : : static void apply_scanjoin_target_to_paths(PlannerInfo *root,
257 : : RelOptInfo *rel,
258 : : List *scanjoin_targets,
259 : : List *scanjoin_targets_contain_srfs,
260 : : bool scanjoin_target_parallel_safe,
261 : : bool tlist_same_exprs);
262 : : static void create_partitionwise_grouping_paths(PlannerInfo *root,
263 : : RelOptInfo *input_rel,
264 : : RelOptInfo *grouped_rel,
265 : : RelOptInfo *partially_grouped_rel,
266 : : const AggClauseCosts *agg_costs,
267 : : grouping_sets_data *gd,
268 : : PartitionwiseAggregateType patype,
269 : : GroupPathExtraData *extra);
270 : : static bool group_by_has_partkey(RelOptInfo *input_rel,
271 : : List *targetList,
272 : : List *groupClause);
273 : : static int common_prefix_cmp(const void *a, const void *b);
274 : : static List *generate_setop_child_grouplist(SetOperationStmt *op,
275 : : List *targetlist);
276 : : static void create_final_unique_paths(PlannerInfo *root, RelOptInfo *input_rel,
277 : : List *sortPathkeys, List *groupClause,
278 : : SpecialJoinInfo *sjinfo, RelOptInfo *unique_rel);
279 : : static void create_partial_unique_paths(PlannerInfo *root, RelOptInfo *input_rel,
280 : : List *sortPathkeys, List *groupClause,
281 : : SpecialJoinInfo *sjinfo, RelOptInfo *unique_rel);
282 : :
283 : :
284 : : /*****************************************************************************
285 : : *
286 : : * Query optimizer entry point
287 : : *
288 : : * Inputs:
289 : : * parse: an analyzed-and-rewritten query tree for an optimizable statement
290 : : * query_string: source text for the query tree (used for error reports)
291 : : * cursorOptions: bitmask of CURSOR_OPT_XXX flags, see parsenodes.h
292 : : * boundParams: passed-in parameter values, or NULL if none
293 : : * es: ExplainState if being called from EXPLAIN, else NULL
294 : : *
295 : : * The result is a PlannedStmt tree.
296 : : *
297 : : * PARAM_EXTERN Param nodes within the parse tree can be replaced by Consts
298 : : * using values from boundParams, if those values are marked PARAM_FLAG_CONST.
299 : : * Parameter values not so marked are still relied on for estimation purposes.
300 : : *
301 : : * The ExplainState pointer is not currently used by the core planner, but it
302 : : * is passed through to some planner hooks so that they can report information
303 : : * back to EXPLAIN extension hooks.
304 : : *
305 : : * To support loadable plugins that monitor or modify planner behavior,
306 : : * we provide a hook variable that lets a plugin get control before and
307 : : * after the standard planning process. The plugin would normally call
308 : : * standard_planner().
309 : : *
310 : : * Note to plugin authors: standard_planner() scribbles on its Query input,
311 : : * so you'd better copy that data structure if you want to plan more than once.
312 : : *
313 : : *****************************************************************************/
314 : : PlannedStmt *
2176 fujii@postgresql.org 315 :CBC 241187 : planner(Query *parse, const char *query_string, int cursorOptions,
316 : : ParamListInfo boundParams, ExplainState *es)
317 : : {
318 : : PlannedStmt *result;
319 : :
6869 tgl@sss.pgh.pa.us 320 [ + + ]: 241187 : if (planner_hook)
158 rhaas@postgresql.org 321 :GNC 50950 : result = (*planner_hook) (parse, query_string, cursorOptions,
322 : : boundParams, es);
323 : : else
324 : 190237 : result = standard_planner(parse, query_string, cursorOptions,
325 : : boundParams, es);
326 : :
356 michael@paquier.xyz 327 :CBC 238752 : pgstat_report_plan_id(result->planId, false);
328 : :
6869 tgl@sss.pgh.pa.us 329 : 238752 : return result;
330 : : }
331 : :
332 : : PlannedStmt *
2176 fujii@postgresql.org 333 : 241187 : standard_planner(Query *parse, const char *query_string, int cursorOptions,
334 : : ParamListInfo boundParams, ExplainState *es)
335 : : {
336 : : PlannedStmt *result;
337 : : PlannerGlobal *glob;
338 : : double tuple_fraction;
339 : : PlannerInfo *root;
340 : : RelOptInfo *final_rel;
341 : : Path *best_path;
342 : : Plan *top_plan;
343 : : ListCell *lp,
344 : : *lr;
345 : :
346 : : /*
347 : : * Set up global state for this planner invocation. This data is needed
348 : : * across all levels of sub-Query that might exist in the given command,
349 : : * so we keep it in a separate struct that's linked to by each per-Query
350 : : * PlannerInfo.
351 : : */
6964 tgl@sss.pgh.pa.us 352 : 241187 : glob = makeNode(PlannerGlobal);
353 : :
354 : 241187 : glob->boundParams = boundParams;
6961 355 : 241187 : glob->subplans = NIL;
719 356 : 241187 : glob->subpaths = NIL;
5307 357 : 241187 : glob->subroots = NIL;
6956 358 : 241187 : glob->rewindPlanIDs = NULL;
6961 359 : 241187 : glob->finalrtable = NIL;
305 rguo@postgresql.org 360 : 241187 : glob->allRelids = NULL;
361 : 241187 : glob->prunableRelids = NULL;
1195 alvherre@alvh.no-ip. 362 : 241187 : glob->finalrteperminfos = NIL;
5998 tgl@sss.pgh.pa.us 363 : 241187 : glob->finalrowmarks = NIL;
5497 364 : 241187 : glob->resultRelations = NIL;
2286 365 : 241187 : glob->appendRelations = NIL;
305 rguo@postgresql.org 366 : 241187 : glob->partPruneInfos = NIL;
6730 tgl@sss.pgh.pa.us 367 : 241187 : glob->relationOids = NIL;
6396 368 : 241187 : glob->invalItems = NIL;
3044 rhaas@postgresql.org 369 : 241187 : glob->paramExecTypes = NIL;
6354 tgl@sss.pgh.pa.us 370 : 241187 : glob->lastPHId = 0;
5513 371 : 241187 : glob->lastRowMarkId = 0;
3821 rhaas@postgresql.org 372 : 241187 : glob->lastPlanNodeId = 0;
6751 tgl@sss.pgh.pa.us 373 : 241187 : glob->transientPlan = false;
3530 374 : 241187 : glob->dependsOnRole = false;
305 rguo@postgresql.org 375 : 241187 : glob->partition_directory = NULL;
236 rguo@postgresql.org 376 :GNC 241187 : glob->rel_notnullatts_hash = NULL;
377 : :
378 : : /*
379 : : * Assess whether it's feasible to use parallel mode for this query. We
380 : : * can't do this in a standalone backend, or if the command will try to
381 : : * modify any data, or if this is a cursor operation, or if GUCs are set
382 : : * to values that don't permit parallelism, or if parallel-unsafe
383 : : * functions are present in the query tree.
384 : : *
385 : : * (Note that we do allow CREATE TABLE AS, SELECT INTO, and CREATE
386 : : * MATERIALIZED VIEW to use parallel plans, but this is safe only because
387 : : * the command is writing into a completely new table which workers won't
388 : : * be able to see. If the workers could see the table, the fact that
389 : : * group locking would cause them to ignore the leader's heavyweight GIN
390 : : * page locks would make this unsafe. We'll have to fix that somehow if
391 : : * we want to allow parallel inserts in general; updates and deletes have
392 : : * additional problems especially around combo CIDs.)
393 : : *
394 : : * For now, we don't try to use parallel mode if we're running inside a
395 : : * parallel worker. We might eventually be able to relax this
396 : : * restriction, but for now it seems best not to have parallel workers
397 : : * trying to create their own parallel workers.
398 : : */
3495 tgl@sss.pgh.pa.us 399 [ + + + + ]:CBC 241187 : if ((cursorOptions & CURSOR_OPT_PARALLEL_OK) != 0 &&
400 : 226692 : IsUnderPostmaster &&
1817 akapila@postgresql.o 401 [ + + ]: 226692 : parse->commandType == CMD_SELECT &&
3495 tgl@sss.pgh.pa.us 402 [ + + ]: 186369 : !parse->hasModifyingCTE &&
403 [ + + ]: 186295 : max_parallel_workers_per_gather > 0 &&
2557 tmunro@postgresql.or 404 [ + + ]: 185867 : !IsParallelWorker())
405 : : {
406 : : /* all the cheap tests pass, so scan the query tree */
1817 akapila@postgresql.o 407 : 185843 : glob->maxParallelHazard = max_parallel_hazard(parse);
3495 tgl@sss.pgh.pa.us 408 : 185843 : glob->parallelModeOK = (glob->maxParallelHazard != PROPARALLEL_UNSAFE);
409 : : }
410 : : else
411 : : {
412 : : /* skip the query tree scan, just assume it's unsafe */
413 : 55344 : glob->maxParallelHazard = PROPARALLEL_UNSAFE;
414 : 55344 : glob->parallelModeOK = false;
415 : : }
416 : :
417 : : /*
418 : : * glob->parallelModeNeeded is normally set to false here and changed to
419 : : * true during plan creation if a Gather or Gather Merge plan is actually
420 : : * created (cf. create_gather_plan, create_gather_merge_plan).
421 : : *
422 : : * However, if debug_parallel_query = on or debug_parallel_query =
423 : : * regress, then we impose parallel mode whenever it's safe to do so, even
424 : : * if the final plan doesn't use parallelism. It's not safe to do so if
425 : : * the query contains anything parallel-unsafe; parallelModeOK will be
426 : : * false in that case. Note that parallelModeOK can't change after this
427 : : * point. Otherwise, everything in the query is either parallel-safe or
428 : : * parallel-restricted, and in either case it should be OK to impose
429 : : * parallel-mode restrictions. If that ends up breaking something, then
430 : : * either some function the user included in the query is incorrectly
431 : : * labeled as parallel-safe or parallel-restricted when in reality it's
432 : : * parallel-unsafe, or else the query planner itself has a bug.
433 : : */
3544 rhaas@postgresql.org 434 [ + + ]: 398063 : glob->parallelModeNeeded = glob->parallelModeOK &&
1124 drowley@postgresql.o 435 [ + + ]: 156876 : (debug_parallel_query != DEBUG_PARALLEL_OFF);
436 : :
437 : : /* Determine what fraction of the plan is likely to be scanned */
6908 tgl@sss.pgh.pa.us 438 [ + + ]: 241187 : if (cursorOptions & CURSOR_OPT_FAST_PLAN)
439 : : {
440 : : /*
441 : : * We have no real idea how many tuples the user will ultimately FETCH
442 : : * from a cursor, but it is often the case that he doesn't want 'em
443 : : * all, or would prefer a fast-start plan anyway so that he can
444 : : * process some of the tuples sooner. Use a GUC parameter to decide
445 : : * what fraction to optimize for.
446 : : */
6526 447 : 2322 : tuple_fraction = cursor_tuple_fraction;
448 : :
449 : : /*
450 : : * We document cursor_tuple_fraction as simply being a fraction, which
451 : : * means the edge cases 0 and 1 have to be treated specially here. We
452 : : * convert 1 to 0 ("all the tuples") and 0 to a very small fraction.
453 : : */
454 [ - + ]: 2322 : if (tuple_fraction >= 1.0)
6526 tgl@sss.pgh.pa.us 455 :UBC 0 : tuple_fraction = 0.0;
6526 tgl@sss.pgh.pa.us 456 [ - + ]:CBC 2322 : else if (tuple_fraction <= 0.0)
6526 tgl@sss.pgh.pa.us 457 :UBC 0 : tuple_fraction = 1e-10;
458 : : }
459 : : else
460 : : {
461 : : /* Default assumption is we need all the tuples */
8406 tgl@sss.pgh.pa.us 462 :CBC 238865 : tuple_fraction = 0.0;
463 : : }
464 : :
465 : : /*
466 : : * Compute the initial path generation strategy mask.
467 : : *
468 : : * Some strategies, such as PGS_FOREIGNJOIN, have no corresponding enable_*
469 : : * GUC, and so the corresponding bits are always set in the default
470 : : * strategy mask.
471 : : *
472 : : * It may seem surprising that enable_indexscan sets both PGS_INDEXSCAN
473 : : * and PGS_INDEXONLYSCAN. However, the historical behavior of this GUC
474 : : * corresponds to this exactly: enable_indexscan=off disables both
475 : : * index-scan and index-only scan paths, whereas enable_indexonlyscan=off
476 : : * converts the index-only scan paths that we would have considered into
477 : : * index scan paths.
478 : : */
46 rhaas@postgresql.org 479 :GNC 241187 : glob->default_pgs_mask = PGS_APPEND | PGS_MERGE_APPEND | PGS_FOREIGNJOIN |
480 : : PGS_GATHER | PGS_CONSIDER_NONPARTIAL;
481 [ + - ]: 241187 : if (enable_tidscan)
482 : 241187 : glob->default_pgs_mask |= PGS_TIDSCAN;
483 [ + + ]: 241187 : if (enable_seqscan)
484 : 228533 : glob->default_pgs_mask |= PGS_SEQSCAN;
485 [ + + ]: 241187 : if (enable_indexscan)
486 : 239842 : glob->default_pgs_mask |= PGS_INDEXSCAN | PGS_INDEXONLYSCAN;
487 [ + + ]: 241187 : if (enable_indexonlyscan)
488 : 240372 : glob->default_pgs_mask |= PGS_CONSIDER_INDEXONLY;
489 [ + + ]: 241187 : if (enable_bitmapscan)
490 : 235418 : glob->default_pgs_mask |= PGS_BITMAPSCAN;
491 [ + + ]: 241187 : if (enable_mergejoin)
492 : : {
493 : 240077 : glob->default_pgs_mask |= PGS_MERGEJOIN_PLAIN;
494 [ + + ]: 240077 : if (enable_material)
495 : 240036 : glob->default_pgs_mask |= PGS_MERGEJOIN_MATERIALIZE;
496 : : }
497 [ + + ]: 241187 : if (enable_nestloop)
498 : : {
499 : 240989 : glob->default_pgs_mask |= PGS_NESTLOOP_PLAIN;
500 [ + + ]: 240989 : if (enable_material)
501 : 240875 : glob->default_pgs_mask |= PGS_NESTLOOP_MATERIALIZE;
502 [ + + ]: 240989 : if (enable_memoize)
503 : 240923 : glob->default_pgs_mask |= PGS_NESTLOOP_MEMOIZE;
504 : : }
505 [ + + ]: 241187 : if (enable_hashjoin)
506 : 239870 : glob->default_pgs_mask |= PGS_HASHJOIN;
507 [ + - ]: 241187 : if (enable_gathermerge)
508 : 241187 : glob->default_pgs_mask |= PGS_GATHER_MERGE;
509 [ + + ]: 241187 : if (enable_partitionwise_join)
510 : 1253 : glob->default_pgs_mask |= PGS_CONSIDER_PARTITIONWISE;
511 : :
512 : : /* Allow plugins to take control after we've initialized "glob" */
158 513 [ + + ]: 241187 : if (planner_setup_hook)
33 514 : 174 : (*planner_setup_hook) (glob, parse, query_string, cursorOptions,
515 : : &tuple_fraction, es);
516 : :
517 : : /* primary planning entry point (may recurse for subqueries) */
159 518 : 241187 : root = subquery_planner(glob, parse, NULL, NULL, false, tuple_fraction,
519 : : NULL);
520 : :
521 : : /* Select best Path and turn it into a Plan */
3660 tgl@sss.pgh.pa.us 522 :CBC 238956 : final_rel = fetch_upper_rel(root, UPPERREL_FINAL, NULL);
523 : 238956 : best_path = get_cheapest_fractional_path(final_rel, tuple_fraction);
524 : :
525 : 238956 : top_plan = create_plan(root, best_path);
526 : :
527 : : /*
528 : : * If creating a plan for a scrollable cursor, make sure it can run
529 : : * backwards on demand. Add a Material node at the top at need.
530 : : */
6908 531 [ + + ]: 238752 : if (cursorOptions & CURSOR_OPT_SCROLL)
532 : : {
6963 533 [ + + ]: 133 : if (!ExecSupportsBackwardScan(top_plan))
3328 534 : 16 : top_plan = materialize_finished_plan(top_plan);
535 : : }
536 : :
537 : : /*
538 : : * Optionally add a Gather node for testing purposes, provided this is
539 : : * actually a safe thing to do.
540 : : *
541 : : * We can add Gather even when top_plan has parallel-safe initPlans, but
542 : : * then we have to move the initPlans to the Gather node because of
543 : : * SS_finalize_plan's limitations. That would cause cosmetic breakage of
544 : : * regression tests when debug_parallel_query = regress, because initPlans
545 : : * that would normally appear on the top_plan move to the Gather, causing
546 : : * them to disappear from EXPLAIN output. That doesn't seem worth kluging
547 : : * EXPLAIN to hide, so skip it when debug_parallel_query = regress.
548 : : */
976 549 [ + + ]: 238752 : if (debug_parallel_query != DEBUG_PARALLEL_OFF &&
550 [ + + ]: 97 : top_plan->parallel_safe &&
551 [ - + ]: 64 : (top_plan->initPlan == NIL ||
976 tgl@sss.pgh.pa.us 552 [ # # ]:UBC 0 : debug_parallel_query != DEBUG_PARALLEL_REGRESS))
553 : : {
3689 rhaas@postgresql.org 554 :CBC 64 : Gather *gather = makeNode(Gather);
555 : : Cost initplan_cost;
556 : : bool unsafe_initplans;
557 : :
558 : 64 : gather->plan.targetlist = top_plan->targetlist;
559 : 64 : gather->plan.qual = NIL;
560 : 64 : gather->plan.lefttree = top_plan;
561 : 64 : gather->plan.righttree = NULL;
562 : 64 : gather->num_workers = 1;
563 : 64 : gather->single_copy = true;
1124 drowley@postgresql.o 564 : 64 : gather->invisible = (debug_parallel_query == DEBUG_PARALLEL_REGRESS);
565 : :
566 : : /* Transfer any initPlans to the new top node */
976 tgl@sss.pgh.pa.us 567 : 64 : gather->plan.initPlan = top_plan->initPlan;
568 : 64 : top_plan->initPlan = NIL;
569 : :
570 : : /*
571 : : * Since this Gather has no parallel-aware descendants to signal to,
572 : : * we don't need a rescan Param.
573 : : */
3119 574 : 64 : gather->rescan_param = -1;
575 : :
576 : : /*
577 : : * Ideally we'd use cost_gather here, but setting up dummy path data
578 : : * to satisfy it doesn't seem much cleaner than knowing what it does.
579 : : */
3542 580 : 64 : gather->plan.startup_cost = top_plan->startup_cost +
581 : : parallel_setup_cost;
582 : 64 : gather->plan.total_cost = top_plan->total_cost +
583 : 64 : parallel_setup_cost + parallel_tuple_cost * top_plan->plan_rows;
584 : 64 : gather->plan.plan_rows = top_plan->plan_rows;
585 : 64 : gather->plan.plan_width = top_plan->plan_width;
586 : 64 : gather->plan.parallel_aware = false;
3259 587 : 64 : gather->plan.parallel_safe = false;
588 : :
589 : : /*
590 : : * Delete the initplans' cost from top_plan. We needn't add it to the
591 : : * Gather node, since the above coding already included it there.
592 : : */
976 593 : 64 : SS_compute_initplan_cost(gather->plan.initPlan,
594 : : &initplan_cost, &unsafe_initplans);
595 : 64 : top_plan->startup_cost -= initplan_cost;
596 : 64 : top_plan->total_cost -= initplan_cost;
597 : :
598 : : /* use parallel mode for parallel plans. */
3689 rhaas@postgresql.org 599 : 64 : root->glob->parallelModeNeeded = true;
600 : :
601 : 64 : top_plan = &gather->plan;
602 : : }
603 : :
604 : : /*
605 : : * If any Params were generated, run through the plan tree and compute
606 : : * each plan node's extParam/allParam sets. Ideally we'd merge this into
607 : : * set_plan_references' tree traversal, but for now it has to be separate
608 : : * because we need to visit subplans before not after main plan.
609 : : */
3044 610 [ + + ]: 238752 : if (glob->paramExecTypes != NIL)
611 : : {
3869 tgl@sss.pgh.pa.us 612 [ - + ]: 81773 : Assert(list_length(glob->subplans) == list_length(glob->subroots));
613 [ + + + + : 106457 : forboth(lp, glob->subplans, lr, glob->subroots)
+ + + + +
+ + - +
+ ]
614 : : {
615 : 24684 : Plan *subplan = (Plan *) lfirst(lp);
3113 616 : 24684 : PlannerInfo *subroot = lfirst_node(PlannerInfo, lr);
617 : :
3869 618 : 24684 : SS_finalize_plan(subroot, subplan);
619 : : }
620 : 81773 : SS_finalize_plan(root, top_plan);
621 : : }
622 : :
623 : : /* final cleanup of the plan */
6961 624 [ - + ]: 238752 : Assert(glob->finalrtable == NIL);
1195 alvherre@alvh.no-ip. 625 [ - + ]: 238752 : Assert(glob->finalrteperminfos == NIL);
5998 tgl@sss.pgh.pa.us 626 [ - + ]: 238752 : Assert(glob->finalrowmarks == NIL);
5497 627 [ - + ]: 238752 : Assert(glob->resultRelations == NIL);
2286 628 [ - + ]: 238752 : Assert(glob->appendRelations == NIL);
5307 629 : 238752 : top_plan = set_plan_references(root, top_plan);
630 : : /* ... and the subplans (both regular subplans and initplans) */
631 [ - + ]: 238752 : Assert(list_length(glob->subplans) == list_length(glob->subroots));
632 [ + + + + : 263436 : forboth(lp, glob->subplans, lr, glob->subroots)
+ + + + +
+ + - +
+ ]
633 : : {
6695 bruce@momjian.us 634 : 24684 : Plan *subplan = (Plan *) lfirst(lp);
3113 tgl@sss.pgh.pa.us 635 : 24684 : PlannerInfo *subroot = lfirst_node(PlannerInfo, lr);
636 : :
5307 637 : 24684 : lfirst(lp) = set_plan_references(subroot, subplan);
638 : : }
639 : :
640 : : /* build the PlannedStmt result */
6963 641 : 238752 : result = makeNode(PlannedStmt);
642 : :
643 : 238752 : result->commandType = parse->commandType;
5101 644 : 238752 : result->queryId = parse->queryId;
227 michael@paquier.xyz 645 :GNC 238752 : result->planOrigin = PLAN_STMT_STANDARD;
6000 tgl@sss.pgh.pa.us 646 :CBC 238752 : result->hasReturning = (parse->returningList != NIL);
5497 647 : 238752 : result->hasModifyingCTE = parse->hasModifyingCTE;
6963 648 : 238752 : result->canSetTag = parse->canSetTag;
6751 649 : 238752 : result->transientPlan = glob->transientPlan;
3530 650 : 238752 : result->dependsOnRole = glob->dependsOnRole;
651 : 238752 : result->parallelModeNeeded = glob->parallelModeNeeded;
6963 652 : 238752 : result->planTree = top_plan;
409 amitlan@postgresql.o 653 : 238752 : result->partPruneInfos = glob->partPruneInfos;
6961 tgl@sss.pgh.pa.us 654 : 238752 : result->rtable = glob->finalrtable;
401 amitlan@postgresql.o 655 : 477504 : result->unprunableRelids = bms_difference(glob->allRelids,
656 : 238752 : glob->prunableRelids);
1195 alvherre@alvh.no-ip. 657 : 238752 : result->permInfos = glob->finalrteperminfos;
33 rhaas@postgresql.org 658 :GNC 238752 : result->subrtinfos = glob->subrtinfos;
5497 tgl@sss.pgh.pa.us 659 :CBC 238752 : result->resultRelations = glob->resultRelations;
2286 660 : 238752 : result->appendRelations = glob->appendRelations;
6961 661 : 238752 : result->subplans = glob->subplans;
6956 662 : 238752 : result->rewindPlanIDs = glob->rewindPlanIDs;
5998 663 : 238752 : result->rowMarks = glob->finalrowmarks;
6730 664 : 238752 : result->relationOids = glob->relationOids;
6396 665 : 238752 : result->invalItems = glob->invalItems;
3044 rhaas@postgresql.org 666 : 238752 : result->paramExecTypes = glob->paramExecTypes;
667 : : /* utilityStmt should be null, but we might as well copy it */
3347 tgl@sss.pgh.pa.us 668 : 238752 : result->utilityStmt = parse->utilityStmt;
33 rhaas@postgresql.org 669 :GNC 238752 : result->elidedNodes = glob->elidedNodes;
3347 tgl@sss.pgh.pa.us 670 :CBC 238752 : result->stmt_location = parse->stmt_location;
671 : 238752 : result->stmt_len = parse->stmt_len;
672 : :
2915 andres@anarazel.de 673 : 238752 : result->jitFlags = PGJIT_NONE;
674 [ + + + - ]: 238752 : if (jit_enabled && jit_above_cost >= 0 &&
675 [ + + ]: 238393 : top_plan->total_cost > jit_above_cost)
676 : : {
677 : 480 : result->jitFlags |= PGJIT_PERFORM;
678 : :
679 : : /*
680 : : * Decide how much effort should be put into generating better code.
681 : : */
682 [ + - ]: 480 : if (jit_optimize_above_cost >= 0 &&
683 [ + + ]: 480 : top_plan->total_cost > jit_optimize_above_cost)
684 : 197 : result->jitFlags |= PGJIT_OPT3;
2909 685 [ + - ]: 480 : if (jit_inline_above_cost >= 0 &&
686 [ + + ]: 480 : top_plan->total_cost > jit_inline_above_cost)
687 : 197 : result->jitFlags |= PGJIT_INLINE;
688 : :
689 : : /*
690 : : * Decide which operations should be JITed.
691 : : */
2917 692 [ + - ]: 480 : if (jit_expressions)
693 : 480 : result->jitFlags |= PGJIT_EXPR;
2911 694 [ + - ]: 480 : if (jit_tuple_deforming)
695 : 480 : result->jitFlags |= PGJIT_DEFORM;
696 : : }
697 : :
698 : : /* Allow plugins to take control before we discard "glob" */
158 rhaas@postgresql.org 699 [ + + ]:GNC 238752 : if (planner_shutdown_hook)
700 : 174 : (*planner_shutdown_hook) (glob, parse, query_string, result);
701 : :
2565 rhaas@postgresql.org 702 [ + + ]:CBC 238752 : if (glob->partition_directory != NULL)
703 : 6107 : DestroyPartitionDirectory(glob->partition_directory);
704 : :
6963 tgl@sss.pgh.pa.us 705 : 238752 : return result;
706 : : }
707 : :
708 : :
709 : : /*--------------------
710 : : * subquery_planner
711 : : * Invokes the planner on a subquery. We recurse to here for each
712 : : * sub-SELECT found in the query tree.
713 : : *
714 : : * glob is the global state for the current planner run.
715 : : * parse is the querytree produced by the parser & rewriter.
716 : : * plan_name is the name to assign to this subplan (NULL at the top level).
717 : : * parent_root is the immediate parent Query's info (NULL at the top level).
718 : : * hasRecursion is true if this is a recursive WITH query.
719 : : * tuple_fraction is the fraction of tuples we expect will be retrieved.
720 : : * tuple_fraction is interpreted as explained for grouping_planner, below.
721 : : * setops is used for set operation subqueries to provide the subquery with
722 : : * the context in which it's being used so that Paths correctly sorted for the
723 : : * set operation can be generated. NULL when not planning a set operation
724 : : * child, or when a child of a set op that isn't interested in sorted input.
725 : : *
726 : : * Basically, this routine does the stuff that should only be done once
727 : : * per Query object. It then calls grouping_planner. At one time,
728 : : * grouping_planner could be invoked recursively on the same Query object;
729 : : * that's not currently true, but we keep the separation between the two
730 : : * routines anyway, in case we need it again someday.
731 : : *
732 : : * subquery_planner will be called recursively to handle sub-Query nodes
733 : : * found within the query's expressions and rangetable.
734 : : *
735 : : * Returns the PlannerInfo struct ("root") that contains all data generated
736 : : * while planning the subquery. In particular, the Path(s) attached to
737 : : * the (UPPERREL_FINAL, NULL) upperrel represent our conclusions about the
738 : : * cheapest way(s) to implement the query. The top level will select the
739 : : * best Path and pass it through createplan.c to produce a finished Plan.
740 : : *--------------------
741 : : */
742 : : PlannerInfo *
159 rhaas@postgresql.org 743 :GNC 287775 : subquery_planner(PlannerGlobal *glob, Query *parse, char *plan_name,
744 : : PlannerInfo *parent_root, bool hasRecursion,
745 : : double tuple_fraction, SetOperationStmt *setops)
746 : : {
747 : : PlannerInfo *root;
748 : : List *newWithCheckOptions;
749 : : List *newHaving;
750 : : bool hasOuterJoins;
751 : : bool hasResultRTEs;
752 : : RelOptInfo *final_rel;
753 : : ListCell *l;
754 : :
755 : : /* Create a PlannerInfo data structure for this subquery */
7588 tgl@sss.pgh.pa.us 756 :CBC 287775 : root = makeNode(PlannerInfo);
757 : 287775 : root->parse = parse;
6964 758 : 287775 : root->glob = glob;
6371 759 [ + + ]: 287775 : root->query_level = parent_root ? parent_root->query_level + 1 : 1;
159 rhaas@postgresql.org 760 :GNC 287775 : root->plan_name = plan_name;
6371 tgl@sss.pgh.pa.us 761 :CBC 287775 : root->parent_root = parent_root;
4939 762 : 287775 : root->plan_params = NIL;
3869 763 : 287775 : root->outer_params = NULL;
6994 764 : 287775 : root->planner_cxt = CurrentMemoryContext;
6964 765 : 287775 : root->init_plans = NIL;
6371 766 : 287775 : root->cte_plan_ids = NIL;
4288 767 : 287775 : root->multiexpr_params = NIL;
1140 768 : 287775 : root->join_domains = NIL;
6994 769 : 287775 : root->eq_classes = NIL;
2429 drowley@postgresql.o 770 : 287775 : root->ec_merging_done = false;
1140 tgl@sss.pgh.pa.us 771 : 287775 : root->last_rinfo_serial = 0;
1810 772 : 287775 : root->all_result_relids =
773 [ + + ]: 287775 : parse->resultRelation ? bms_make_singleton(parse->resultRelation) : NULL;
774 : 287775 : root->leaf_result_relids = NULL; /* we'll find out leaf-ness later */
7348 775 : 287775 : root->append_rel_list = NIL;
1810 776 : 287775 : root->row_identity_vars = NIL;
5984 777 : 287775 : root->rowMarks = NIL;
3660 778 : 287775 : memset(root->upper_rels, 0, sizeof(root->upper_rels));
3653 779 : 287775 : memset(root->upper_targets, 0, sizeof(root->upper_targets));
1152 780 : 287775 : root->processed_groupClause = NIL;
781 : 287775 : root->processed_distinctClause = NIL;
3660 782 : 287775 : root->processed_tlist = NIL;
1810 783 : 287775 : root->update_colnos = NIL;
3956 andres@anarazel.de 784 : 287775 : root->grouping_map = NULL;
3660 tgl@sss.pgh.pa.us 785 : 287775 : root->minmax_aggs = NIL;
3343 786 : 287775 : root->qual_security_level = 0;
1995 787 : 287775 : root->hasPseudoConstantQuals = false;
788 : 287775 : root->hasAlternativeSubPlans = false;
1306 789 : 287775 : root->placeholdersFrozen = false;
6371 790 : 287775 : root->hasRecursion = hasRecursion;
207 rhaas@postgresql.org 791 :GNC 287775 : root->assumeReplanning = false;
6371 tgl@sss.pgh.pa.us 792 [ + + ]:CBC 287775 : if (hasRecursion)
2620 793 : 543 : root->wt_param_id = assign_special_exec_param(root);
794 : : else
6371 795 : 287232 : root->wt_param_id = -1;
3660 796 : 287775 : root->non_recursive_path = NULL;
797 : :
798 : : /*
799 : : * Create the top-level join domain. This won't have valid contents until
800 : : * deconstruct_jointree fills it in, but the node needs to exist before
801 : : * that so we can build EquivalenceClasses referencing it.
802 : : */
1140 803 : 287775 : root->join_domains = list_make1(makeNode(JoinDomain));
804 : :
805 : : /*
806 : : * If there is a WITH list, process each WITH query and either convert it
807 : : * to RTE_SUBQUERY RTE(s) or build an initplan SubPlan structure for it.
808 : : */
6371 809 [ + + ]: 287775 : if (parse->cteList)
810 : 1611 : SS_process_ctes(root);
811 : :
812 : : /*
813 : : * If it's a MERGE command, transform the joinlist as appropriate.
814 : : */
1448 alvherre@alvh.no-ip. 815 : 287772 : transform_MERGE_to_join(parse);
816 : :
817 : : /*
818 : : * Scan the rangetable for relation RTEs and retrieve the necessary
819 : : * catalog information for each relation. Using this information, clear
820 : : * the inh flag for any relation that has no children, collect not-null
821 : : * attribute numbers for any relation that has column not-null
822 : : * constraints, and expand virtual generated columns for any relation that
823 : : * contains them. Note that this step does not descend into sublinks and
824 : : * subqueries; if we pull up any sublinks or subqueries below, their
825 : : * relation RTEs are processed just before pulling them up.
826 : : */
236 rguo@postgresql.org 827 :GNC 287772 : parse = root->parse = preprocess_relation_rtes(root);
828 : :
829 : : /*
830 : : * If the FROM clause is empty, replace it with a dummy RTE_RESULT RTE, so
831 : : * that we don't need so many special cases to deal with that situation.
832 : : */
2603 tgl@sss.pgh.pa.us 833 :CBC 287772 : replace_empty_jointree(parse);
834 : :
835 : : /*
836 : : * Look for ANY and EXISTS SubLinks in WHERE and JOIN/ON clauses, and try
837 : : * to transform them into joins. Note that this step does not descend
838 : : * into subqueries; if we pull up any subqueries below, their SubLinks are
839 : : * processed just before pulling them up.
840 : : */
8455 841 [ + + ]: 287772 : if (parse->hasSubLinks)
6419 842 : 22123 : pull_up_sublinks(root);
843 : :
844 : : /*
845 : : * Scan the rangetable for function RTEs, do const-simplification on them,
846 : : * and then inline them if possible (producing subqueries that might get
847 : : * pulled up next). Recursion issues here are handled in the same way as
848 : : * for SubLinks.
849 : : */
2418 850 : 287772 : preprocess_function_rtes(root);
851 : :
852 : : /*
853 : : * Check to see if any subqueries in the jointree can be merged into this
854 : : * query.
855 : : */
4022 856 : 287769 : pull_up_subqueries(root);
857 : :
858 : : /*
859 : : * If this is a simple UNION ALL query, flatten it into an appendrel. We
860 : : * do this now because it requires applying pull_up_subqueries to the leaf
861 : : * queries of the UNION ALL, which weren't touched above because they
862 : : * weren't referenced by the jointree (they will be after we do this).
863 : : */
5606 864 [ + + ]: 287766 : if (parse->setOperations)
865 : 3722 : flatten_simple_union_all(root);
866 : :
867 : : /*
868 : : * Survey the rangetable to see what kinds of entries are present. We can
869 : : * skip some later processing if relevant SQL features are not used; for
870 : : * example if there are no JOIN RTEs we can avoid the expense of doing
871 : : * flatten_join_alias_vars(). This must be done after we have finished
872 : : * adding rangetable entries, of course. (Note: actually, processing of
873 : : * inherited or partitioned rels can cause RTEs for their child tables to
874 : : * get added later; but those must all be RTE_RELATION entries, so they
875 : : * don't invalidate the conclusions drawn here.)
876 : : */
7588 877 : 287766 : root->hasJoinRTEs = false;
4949 878 : 287766 : root->hasLateralRTEs = false;
551 rguo@postgresql.org 879 : 287766 : root->group_rtindex = 0;
6422 tgl@sss.pgh.pa.us 880 : 287766 : hasOuterJoins = false;
2603 881 : 287766 : hasResultRTEs = false;
7963 neilc@samurai.com 882 [ + - + + : 792843 : foreach(l, parse->rtable)
+ + ]
883 : : {
3113 tgl@sss.pgh.pa.us 884 : 505077 : RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
885 : :
2542 886 [ + + + + : 505077 : switch (rte->rtekind)
+ ]
887 : : {
888 : 55559 : case RTE_JOIN:
889 : 55559 : root->hasJoinRTEs = true;
890 [ + + ]: 55559 : if (IS_OUTER_JOIN(rte->jointype))
891 : 27393 : hasOuterJoins = true;
892 : 55559 : break;
893 : 103035 : case RTE_RESULT:
894 : 103035 : hasResultRTEs = true;
895 : 103035 : break;
551 rguo@postgresql.org 896 : 2557 : case RTE_GROUP:
897 [ - + ]: 2557 : Assert(parse->hasGroupRTE);
898 : 2557 : root->group_rtindex = list_cell_number(parse->rtable, l) + 1;
899 : 2557 : break;
2542 tgl@sss.pgh.pa.us 900 : 343926 : default:
901 : : /* No work here for other RTE types */
902 : 343926 : break;
903 : : }
904 : :
4949 905 [ + + ]: 505077 : if (rte->lateral)
906 : 6144 : root->hasLateralRTEs = true;
907 : :
908 : : /*
909 : : * We can also determine the maximum security level required for any
910 : : * securityQuals now. Addition of inheritance-child RTEs won't affect
911 : : * this, because child tables don't have their own securityQuals; see
912 : : * expand_single_inheritance_child().
913 : : */
2541 914 [ + + ]: 505077 : if (rte->securityQuals)
915 [ - + ]: 1443 : root->qual_security_level = Max(root->qual_security_level,
916 : : list_length(rte->securityQuals));
917 : : }
918 : :
919 : : /*
920 : : * If we have now verified that the query target relation is
921 : : * non-inheriting, mark it as a leaf target.
922 : : */
1810 923 [ + + ]: 287766 : if (parse->resultRelation)
924 : : {
925 : 43846 : RangeTblEntry *rte = rt_fetch(parse->resultRelation, parse->rtable);
926 : :
927 [ + + ]: 43846 : if (!rte->inh)
928 : 42358 : root->leaf_result_relids =
929 : 42358 : bms_make_singleton(parse->resultRelation);
930 : : }
931 : :
932 : : /*
933 : : * This would be a convenient time to check access permissions for all
934 : : * relations mentioned in the query, since it would be better to fail now,
935 : : * before doing any detailed planning. However, for historical reasons,
936 : : * we leave this to be done at executor startup.
937 : : *
938 : : * Note, however, that we do need to check access permissions for any view
939 : : * relations mentioned in the query, in order to prevent information being
940 : : * leaked by selectivity estimation functions, which only check view owner
941 : : * permissions on underlying tables (see all_rows_selectable() and its
942 : : * callers). This is a little ugly, because it means that access
943 : : * permissions for views will be checked twice, which is another reason
944 : : * why it would be better to do all the ACL checks here.
945 : : */
216 dean.a.rasheed@gmail 946 [ + - + + : 792249 : foreach(l, parse->rtable)
+ + ]
947 : : {
948 : 504684 : RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
949 : :
950 [ + + ]: 504684 : if (rte->perminfoindex != 0 &&
951 [ + + ]: 272652 : rte->relkind == RELKIND_VIEW)
952 : : {
953 : : RTEPermissionInfo *perminfo;
954 : : bool result;
955 : :
956 : 11787 : perminfo = getRTEPermissionInfo(parse->rteperminfos, rte);
957 : 11787 : result = ExecCheckOneRelPerms(perminfo);
958 [ + + ]: 11787 : if (!result)
959 : 201 : aclcheck_error(ACLCHECK_NO_PRIV, OBJECT_VIEW,
960 : 201 : get_rel_name(perminfo->relid));
961 : : }
962 : : }
963 : :
964 : : /*
965 : : * Preprocess RowMark information. We need to do this after subquery
966 : : * pullup, so that all base relations are present.
967 : : */
5984 tgl@sss.pgh.pa.us 968 : 287565 : preprocess_rowmarks(root);
969 : :
970 : : /*
971 : : * Set hasHavingQual to remember if HAVING clause is present. Needed
972 : : * because preprocess_expression will reduce a constant-true condition to
973 : : * an empty qual list ... but "HAVING TRUE" is not a semantic no-op.
974 : : */
7588 975 : 287565 : root->hasHavingQual = (parse->havingQual != NULL);
976 : :
977 : : /*
978 : : * Do expression preprocessing on targetlist and quals, as well as other
979 : : * random expressions in the querytree. Note that we do not need to
980 : : * handle sort/group expressions explicitly, because they are actually
981 : : * part of the targetlist.
982 : : */
9490 983 : 285577 : parse->targetList = (List *)
7588 984 : 287565 : preprocess_expression(root, (Node *) parse->targetList,
985 : : EXPRKIND_TARGET);
986 : :
4623 sfrost@snowman.net 987 : 285577 : newWithCheckOptions = NIL;
988 [ + + + + : 287139 : foreach(l, parse->withCheckOptions)
+ + ]
989 : : {
3113 tgl@sss.pgh.pa.us 990 : 1562 : WithCheckOption *wco = lfirst_node(WithCheckOption, l);
991 : :
4623 sfrost@snowman.net 992 : 1562 : wco->qual = preprocess_expression(root, wco->qual,
993 : : EXPRKIND_QUAL);
994 [ + + ]: 1562 : if (wco->qual != NULL)
995 : 1362 : newWithCheckOptions = lappend(newWithCheckOptions, wco);
996 : : }
997 : 285577 : parse->withCheckOptions = newWithCheckOptions;
998 : :
7155 tgl@sss.pgh.pa.us 999 : 285577 : parse->returningList = (List *)
1000 : 285577 : preprocess_expression(root, (Node *) parse->returningList,
1001 : : EXPRKIND_TARGET);
1002 : :
7588 1003 : 285577 : preprocess_qual_conditions(root, (Node *) parse->jointree);
1004 : :
1005 : 285577 : parse->havingQual = preprocess_expression(root, parse->havingQual,
1006 : : EXPRKIND_QUAL);
1007 : :
5875 1008 [ + + + + : 287044 : foreach(l, parse->windowClause)
+ + ]
1009 : : {
3113 1010 : 1467 : WindowClause *wc = lfirst_node(WindowClause, l);
1011 : :
1012 : : /* partitionClause/orderClause are sort/group expressions */
5875 1013 : 1467 : wc->startOffset = preprocess_expression(root, wc->startOffset,
1014 : : EXPRKIND_LIMIT);
1015 : 1467 : wc->endOffset = preprocess_expression(root, wc->endOffset,
1016 : : EXPRKIND_LIMIT);
1017 : : }
1018 : :
7588 1019 : 285577 : parse->limitOffset = preprocess_expression(root, parse->limitOffset,
1020 : : EXPRKIND_LIMIT);
1021 : 285577 : parse->limitCount = preprocess_expression(root, parse->limitCount,
1022 : : EXPRKIND_LIMIT);
1023 : :
3964 andres@anarazel.de 1024 [ + + ]: 285577 : if (parse->onConflict)
1025 : : {
3595 tgl@sss.pgh.pa.us 1026 : 2290 : parse->onConflict->arbiterElems = (List *)
1027 : 1145 : preprocess_expression(root,
1028 : 1145 : (Node *) parse->onConflict->arbiterElems,
1029 : : EXPRKIND_ARBITER_ELEM);
1030 : 2290 : parse->onConflict->arbiterWhere =
1031 : 1145 : preprocess_expression(root,
1032 : 1145 : parse->onConflict->arbiterWhere,
1033 : : EXPRKIND_QUAL);
3964 andres@anarazel.de 1034 : 2290 : parse->onConflict->onConflictSet = (List *)
3595 tgl@sss.pgh.pa.us 1035 : 1145 : preprocess_expression(root,
1036 : 1145 : (Node *) parse->onConflict->onConflictSet,
1037 : : EXPRKIND_TARGET);
3964 andres@anarazel.de 1038 : 1145 : parse->onConflict->onConflictWhere =
3595 tgl@sss.pgh.pa.us 1039 : 1145 : preprocess_expression(root,
1040 : 1145 : parse->onConflict->onConflictWhere,
1041 : : EXPRKIND_QUAL);
1042 : : /* exclRelTlist contains only Vars, so no preprocessing needed */
1043 : : }
1044 : :
1448 alvherre@alvh.no-ip. 1045 [ + + + + : 287023 : foreach(l, parse->mergeActionList)
+ + ]
1046 : : {
1047 : 1446 : MergeAction *action = (MergeAction *) lfirst(l);
1048 : :
1049 : 1446 : action->targetList = (List *)
1050 : 1446 : preprocess_expression(root,
1051 : 1446 : (Node *) action->targetList,
1052 : : EXPRKIND_TARGET);
1053 : 1446 : action->qual =
1054 : 1446 : preprocess_expression(root,
1055 : : (Node *) action->qual,
1056 : : EXPRKIND_QUAL);
1057 : : }
1058 : :
715 dean.a.rasheed@gmail 1059 : 285577 : parse->mergeJoinCondition =
1060 : 285577 : preprocess_expression(root, parse->mergeJoinCondition, EXPRKIND_QUAL);
1061 : :
7348 tgl@sss.pgh.pa.us 1062 : 285577 : root->append_rel_list = (List *)
1063 : 285577 : preprocess_expression(root, (Node *) root->append_rel_list,
1064 : : EXPRKIND_APPINFO);
1065 : :
1066 : : /* Also need to preprocess expressions within RTEs */
7963 neilc@samurai.com 1067 [ + - + + : 787768 : foreach(l, parse->rtable)
+ + ]
1068 : : {
3113 tgl@sss.pgh.pa.us 1069 : 502191 : RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
1070 : : int kind;
1071 : : ListCell *lcsq;
1072 : :
3957 simon@2ndQuadrant.co 1073 [ + + ]: 502191 : if (rte->rtekind == RTE_RELATION)
1074 : : {
1075 [ + + ]: 263019 : if (rte->tablesample)
3886 tgl@sss.pgh.pa.us 1076 : 114 : rte->tablesample = (TableSampleClause *)
1077 : 114 : preprocess_expression(root,
1078 : 114 : (Node *) rte->tablesample,
1079 : : EXPRKIND_TABLESAMPLE);
1080 : : }
3957 simon@2ndQuadrant.co 1081 [ + + ]: 239172 : else if (rte->rtekind == RTE_SUBQUERY)
1082 : : {
1083 : : /*
1084 : : * We don't want to do all preprocessing yet on the subquery's
1085 : : * expressions, since that will happen when we plan it. But if it
1086 : : * contains any join aliases of our level, those have to get
1087 : : * expanded now, because planning of the subquery won't do it.
1088 : : * That's only possible if the subquery is LATERAL.
1089 : : */
4944 tgl@sss.pgh.pa.us 1090 [ + + + + ]: 44431 : if (rte->lateral && root->hasJoinRTEs)
1091 : 1122 : rte->subquery = (Query *)
1140 1092 : 1122 : flatten_join_alias_vars(root, root->parse,
2602 1093 : 1122 : (Node *) rte->subquery);
1094 : : }
4944 1095 [ + + ]: 194741 : else if (rte->rtekind == RTE_FUNCTION)
1096 : : {
1097 : : /* Preprocess the function expression(s) fully */
1098 [ + + ]: 27920 : kind = rte->lateral ? EXPRKIND_RTFUNC_LATERAL : EXPRKIND_RTFUNC;
3294 alvherre@alvh.no-ip. 1099 : 27920 : rte->functions = (List *)
1100 : 27920 : preprocess_expression(root, (Node *) rte->functions, kind);
1101 : : }
1102 [ + + ]: 166821 : else if (rte->rtekind == RTE_TABLEFUNC)
1103 : : {
1104 : : /* Preprocess the function expression(s) fully */
1105 [ + + ]: 311 : kind = rte->lateral ? EXPRKIND_TABLEFUNC_LATERAL : EXPRKIND_TABLEFUNC;
1106 : 311 : rte->tablefunc = (TableFunc *)
1107 : 311 : preprocess_expression(root, (Node *) rte->tablefunc, kind);
1108 : : }
7165 mail@joeconway.com 1109 [ + + ]: 166510 : else if (rte->rtekind == RTE_VALUES)
1110 : : {
1111 : : /* Preprocess the values lists fully */
4944 tgl@sss.pgh.pa.us 1112 [ + + ]: 4332 : kind = rte->lateral ? EXPRKIND_VALUES_LATERAL : EXPRKIND_VALUES;
7165 mail@joeconway.com 1113 : 4332 : rte->values_lists = (List *)
4944 tgl@sss.pgh.pa.us 1114 : 4332 : preprocess_expression(root, (Node *) rte->values_lists, kind);
1115 : : }
551 rguo@postgresql.org 1116 [ + + ]: 162178 : else if (rte->rtekind == RTE_GROUP)
1117 : : {
1118 : : /* Preprocess the groupexprs list fully */
1119 : 2557 : rte->groupexprs = (List *)
1120 : 2557 : preprocess_expression(root, (Node *) rte->groupexprs,
1121 : : EXPRKIND_GROUPEXPR);
1122 : : }
1123 : :
1124 : : /*
1125 : : * Process each element of the securityQuals list as if it were a
1126 : : * separate qual expression (as indeed it is). We need to do it this
1127 : : * way to get proper canonicalization of AND/OR structure. Note that
1128 : : * this converts each element into an implicit-AND sublist.
1129 : : */
3343 tgl@sss.pgh.pa.us 1130 [ + + + + : 503831 : foreach(lcsq, rte->securityQuals)
+ + ]
1131 : : {
1132 : 1640 : lfirst(lcsq) = preprocess_expression(root,
1133 : 1640 : (Node *) lfirst(lcsq),
1134 : : EXPRKIND_QUAL);
1135 : : }
1136 : : }
1137 : :
1138 : : /*
1139 : : * Now that we are done preprocessing expressions, and in particular done
1140 : : * flattening join alias variables, get rid of the joinaliasvars lists.
1141 : : * They no longer match what expressions in the rest of the tree look
1142 : : * like, because we have not preprocessed expressions in those lists (and
1143 : : * do not want to; for example, expanding a SubLink there would result in
1144 : : * a useless unreferenced subplan). Leaving them in place simply creates
1145 : : * a hazard for later scans of the tree. We could try to prevent that by
1146 : : * using QTW_IGNORE_JOINALIASES in every tree scan done after this point,
1147 : : * but that doesn't sound very reliable.
1148 : : */
3064 1149 [ + + ]: 285577 : if (root->hasJoinRTEs)
1150 : : {
1151 [ + - + + : 191332 : foreach(l, parse->rtable)
+ + ]
1152 : : {
1153 : 157252 : RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
1154 : :
1155 : 157252 : rte->joinaliasvars = NIL;
1156 : : }
1157 : : }
1158 : :
1159 : : /*
1160 : : * Replace any Vars in the subquery's targetlist and havingQual that
1161 : : * reference GROUP outputs with the underlying grouping expressions.
1162 : : *
1163 : : * Note that we need to perform this replacement after we've preprocessed
1164 : : * the grouping expressions. This is to ensure that there is only one
1165 : : * instance of SubPlan for each SubLink contained within the grouping
1166 : : * expressions.
1167 : : */
551 rguo@postgresql.org 1168 [ + + ]: 285577 : if (parse->hasGroupRTE)
1169 : : {
1170 : 2557 : parse->targetList = (List *)
1171 : 2557 : flatten_group_exprs(root, root->parse, (Node *) parse->targetList);
1172 : 2557 : parse->havingQual =
1173 : 2557 : flatten_group_exprs(root, root->parse, parse->havingQual);
1174 : : }
1175 : :
1176 : : /* Constant-folding might have removed all set-returning functions */
1177 [ + + ]: 285577 : if (parse->hasTargetSRFs)
1178 : 6519 : parse->hasTargetSRFs = expression_returns_set((Node *) parse->targetList);
1179 : :
1180 : : /*
1181 : : * If we have grouping sets, expand the groupingSets tree of this query to
1182 : : * a flat list of grouping sets. We need to do this before optimizing
1183 : : * HAVING, since we can't easily tell if there's an empty grouping set
1184 : : * until we have this representation.
1185 : : */
145 1186 [ + + ]: 285577 : if (parse->groupingSets)
1187 : : {
1188 : 519 : parse->groupingSets =
1189 : 519 : expand_grouping_sets(parse->groupingSets, parse->groupDistinct, -1);
1190 : : }
1191 : :
1192 : : /*
1193 : : * In some cases we may want to transfer a HAVING clause into WHERE. We
1194 : : * cannot do so if the HAVING clause contains aggregates (obviously) or
1195 : : * volatile functions (since a HAVING clause is supposed to be executed
1196 : : * only once per group). We also can't do this if there are any grouping
1197 : : * sets and the clause references any columns that are nullable by the
1198 : : * grouping sets; the nulled values of those columns are not available
1199 : : * before the grouping step. (The test on groupClause might seem wrong,
1200 : : * but it's okay: it's just an optimization to avoid running pull_varnos
1201 : : * when there cannot be any Vars in the HAVING clause.)
1202 : : *
1203 : : * Also, it may be that the clause is so expensive to execute that we're
1204 : : * better off doing it only once per group, despite the loss of
1205 : : * selectivity. This is hard to estimate short of doing the entire
1206 : : * planning process twice, so we use a heuristic: clauses containing
1207 : : * subplans are left in HAVING. Otherwise, we move or copy the HAVING
1208 : : * clause into WHERE, in hopes of eliminating tuples before aggregation
1209 : : * instead of after.
1210 : : *
1211 : : * If the query has no empty grouping set then we can simply move such a
1212 : : * clause into WHERE; any group that fails the clause will not be in the
1213 : : * output because none of its tuples will reach the grouping or
1214 : : * aggregation stage. Otherwise we have to keep the clause in HAVING to
1215 : : * ensure that we don't emit a bogus aggregated row. But then the HAVING
1216 : : * clause must be degenerate (variable-free), so we can copy it into WHERE
1217 : : * so that query_planner() can use it in a gating Result node. (This could
1218 : : * be done better, but it seems not worth optimizing.)
1219 : : *
1220 : : * Note that a HAVING clause may contain expressions that are not fully
1221 : : * preprocessed. This can happen if these expressions are part of
1222 : : * grouping items. In such cases, they are replaced with GROUP Vars in
1223 : : * the parser and then replaced back after we're done with expression
1224 : : * preprocessing on havingQual. This is not an issue if the clause
1225 : : * remains in HAVING, because these expressions will be matched to lower
1226 : : * target items in setrefs.c. However, if the clause is moved or copied
1227 : : * into WHERE, we need to ensure that these expressions are fully
1228 : : * preprocessed.
1229 : : *
1230 : : * Note that both havingQual and parse->jointree->quals are in
1231 : : * implicitly-ANDed-list form at this point, even though they are declared
1232 : : * as Node *.
1233 : : */
9187 tgl@sss.pgh.pa.us 1234 : 285577 : newHaving = NIL;
7963 neilc@samurai.com 1235 [ + + + + : 286271 : foreach(l, (List *) parse->havingQual)
+ + ]
1236 : : {
1237 : 694 : Node *havingclause = (Node *) lfirst(l);
1238 : :
522 rguo@postgresql.org 1239 [ + + + - ]: 952 : if (contain_agg_clause(havingclause) ||
7675 tgl@sss.pgh.pa.us 1240 [ + - ]: 516 : contain_volatile_functions(havingclause) ||
522 rguo@postgresql.org 1241 : 258 : contain_subplans(havingclause) ||
1242 [ + + + + : 318 : (parse->groupClause && parse->groupingSets &&
+ + ]
1243 : 60 : bms_is_member(root->group_rtindex, pull_varnos(root, havingclause))))
1244 : : {
1245 : : /* keep it in HAVING */
9187 tgl@sss.pgh.pa.us 1246 : 472 : newHaving = lappend(newHaving, havingclause);
1247 : : }
145 rguo@postgresql.org 1248 [ + + ]: 222 : else if (parse->groupClause &&
1249 [ + + ]: 204 : (parse->groupingSets == NIL ||
1250 [ + + ]: 24 : (List *) linitial(parse->groupingSets) != NIL))
7675 tgl@sss.pgh.pa.us 1251 : 198 : {
1252 : : /* There is GROUP BY, but no empty grouping set */
1253 : : Node *whereclause;
1254 : :
1255 : : /* Preprocess the HAVING clause fully */
551 rguo@postgresql.org 1256 : 198 : whereclause = preprocess_expression(root, havingclause,
1257 : : EXPRKIND_QUAL);
1258 : : /* ... and move it to WHERE */
9187 tgl@sss.pgh.pa.us 1259 : 198 : parse->jointree->quals = (Node *)
551 rguo@postgresql.org 1260 : 198 : list_concat((List *) parse->jointree->quals,
1261 : : (List *) whereclause);
1262 : : }
1263 : : else
1264 : : {
1265 : : /* There is an empty grouping set (perhaps implicitly) */
1266 : : Node *whereclause;
1267 : :
1268 : : /* Preprocess the HAVING clause fully */
1269 : 24 : whereclause = preprocess_expression(root, copyObject(havingclause),
1270 : : EXPRKIND_QUAL);
1271 : : /* ... and put a copy in WHERE */
7675 tgl@sss.pgh.pa.us 1272 : 48 : parse->jointree->quals = (Node *)
551 rguo@postgresql.org 1273 : 24 : list_concat((List *) parse->jointree->quals,
1274 : : (List *) whereclause);
1275 : : /* ... and also keep it in HAVING */
7675 tgl@sss.pgh.pa.us 1276 : 24 : newHaving = lappend(newHaving, havingclause);
1277 : : }
1278 : : }
9187 1279 : 285577 : parse->havingQual = (Node *) newHaving;
1280 : :
1281 : : /*
1282 : : * If we have any outer joins, try to reduce them to plain inner joins.
1283 : : * This step is most easily done after we've done expression
1284 : : * preprocessing.
1285 : : */
6422 1286 [ + + ]: 285577 : if (hasOuterJoins)
7588 1287 : 18732 : reduce_outer_joins(root);
1288 : :
1289 : : /*
1290 : : * If we have any RTE_RESULT relations, see if they can be deleted from
1291 : : * the jointree. We also rely on this processing to flatten single-child
1292 : : * FromExprs underneath outer joins. This step is most effectively done
1293 : : * after we've done expression preprocessing and outer join reduction.
1294 : : */
1140 1295 [ + + + + ]: 285577 : if (hasResultRTEs || hasOuterJoins)
2603 1296 : 118982 : remove_useless_result_rtes(root);
1297 : :
1298 : : /*
1299 : : * Do the main planning.
1300 : : */
663 rhaas@postgresql.org 1301 : 285577 : grouping_planner(root, tuple_fraction, setops);
1302 : :
1303 : : /*
1304 : : * Capture the set of outer-level param IDs we have access to, for use in
1305 : : * extParam/allParam calculations later.
1306 : : */
3869 tgl@sss.pgh.pa.us 1307 : 285541 : SS_identify_outer_params(root);
1308 : :
1309 : : /*
1310 : : * If any initPlans were created in this query level, adjust the surviving
1311 : : * Paths' costs and parallel-safety flags to account for them. The
1312 : : * initPlans won't actually get attached to the plan tree till
1313 : : * create_plan() runs, but we must include their effects now.
1314 : : */
3660 1315 : 285541 : final_rel = fetch_upper_rel(root, UPPERREL_FINAL, NULL);
1316 : 285541 : SS_charge_for_initplans(root, final_rel);
1317 : :
1318 : : /*
1319 : : * Make sure we've identified the cheapest Path for the final rel. (By
1320 : : * doing this here not in grouping_planner, we include initPlan costs in
1321 : : * the decision, though it's unlikely that will change anything.)
1322 : : */
1323 : 285541 : set_cheapest(final_rel);
1324 : :
1325 : 285541 : return root;
1326 : : }
1327 : :
1328 : : /*
1329 : : * preprocess_expression
1330 : : * Do subquery_planner's preprocessing work for an expression,
1331 : : * which can be a targetlist, a WHERE clause (including JOIN/ON
1332 : : * conditions), a HAVING clause, or a few other things.
1333 : : */
1334 : : static Node *
7588 1335 : 2406702 : preprocess_expression(PlannerInfo *root, Node *expr, int kind)
1336 : : {
1337 : : /*
1338 : : * Fall out quickly if expression is empty. This occurs often enough to
1339 : : * be worth checking. Note that null->null is the correct conversion for
1340 : : * implicit-AND result format, too.
1341 : : */
7594 1342 [ + + ]: 2406702 : if (expr == NULL)
1343 : 1889483 : return NULL;
1344 : :
1345 : : /*
1346 : : * If the query has any join RTEs, replace join alias variables with
1347 : : * base-relation variables. We must do this first, since any expressions
1348 : : * we may extract from the joinaliasvars lists have not been preprocessed.
1349 : : * For example, if we did this after sublink processing, sublinks expanded
1350 : : * out from join aliases would not get processed. But we can skip this in
1351 : : * non-lateral RTE functions, VALUES lists, and TABLESAMPLE clauses, since
1352 : : * they can't contain any Vars of the current query level.
1353 : : */
4944 1354 [ + + + + ]: 517219 : if (root->hasJoinRTEs &&
3886 1355 [ + + + - ]: 244281 : !(kind == EXPRKIND_RTFUNC ||
1356 [ + + ]: 122049 : kind == EXPRKIND_VALUES ||
1357 : : kind == EXPRKIND_TABLESAMPLE ||
1358 : : kind == EXPRKIND_TABLEFUNC))
1140 1359 : 122040 : expr = flatten_join_alias_vars(root, root->parse, expr);
1360 : :
1361 : : /*
1362 : : * Simplify constant expressions. For function RTEs, this was already
1363 : : * done by preprocess_function_rtes. (But note we must do it again for
1364 : : * EXPRKIND_RTFUNC_LATERAL, because those might by now contain
1365 : : * un-simplified subexpressions inserted by flattening of subqueries or
1366 : : * join alias variables.)
1367 : : *
1368 : : * Note: an essential effect of this is to convert named-argument function
1369 : : * calls to positional notation and insert the current actual values of
1370 : : * any default arguments for functions. To ensure that happens, we *must*
1371 : : * process all expressions here. Previous PG versions sometimes skipped
1372 : : * const-simplification if it didn't seem worth the trouble, but we can't
1373 : : * do that anymore.
1374 : : *
1375 : : * Note: this also flattens nested AND and OR expressions into N-argument
1376 : : * form. All processing of a qual expression after this point must be
1377 : : * careful to maintain AND/OR flatness --- that is, do not generate a tree
1378 : : * with AND directly under AND, nor OR directly under OR.
1379 : : */
1613 1380 [ + + ]: 517219 : if (kind != EXPRKIND_RTFUNC)
2418 1381 : 493853 : expr = eval_const_expressions(root, expr);
1382 : :
1383 : : /*
1384 : : * If it's a qual or havingQual, canonicalize it.
1385 : : */
8455 1386 [ + + ]: 515231 : if (kind == EXPRKIND_QUAL)
1387 : : {
2926 1388 : 193220 : expr = (Node *) canonicalize_qual((Expr *) expr, false);
1389 : :
1390 : : #ifdef OPTIMIZER_DEBUG
1391 : : printf("After canonicalize_qual()\n");
1392 : : pprint(expr);
1393 : : #endif
1394 : : }
1395 : :
1396 : : /*
1397 : : * Check for ANY ScalarArrayOpExpr with Const arrays and set the
1398 : : * hashfuncid of any that might execute more quickly by using hash lookups
1399 : : * instead of a linear search.
1400 : : */
1802 drowley@postgresql.o 1401 [ + + + + ]: 515231 : if (kind == EXPRKIND_QUAL || kind == EXPRKIND_TARGET)
1402 : : {
1403 : 472465 : convert_saop_to_hashed_saop(expr);
1404 : : }
1405 : :
1406 : : /* Expand SubLinks to SubPlans */
7588 tgl@sss.pgh.pa.us 1407 [ + + ]: 515231 : if (root->parse->hasSubLinks)
6964 1408 : 64545 : expr = SS_process_sublinks(root, expr, (kind == EXPRKIND_QUAL));
1409 : :
1410 : : /*
1411 : : * XXX do not insert anything here unless you have grokked the comments in
1412 : : * SS_replace_correlation_vars ...
1413 : : */
1414 : :
1415 : : /* Replace uplevel vars with Param nodes (this IS possible in VALUES) */
1416 [ + + ]: 515231 : if (root->query_level > 1)
1417 : 108951 : expr = SS_replace_correlation_vars(root, expr);
1418 : :
1419 : : /*
1420 : : * If it's a qual or havingQual, convert it to implicit-AND format. (We
1421 : : * don't want to do this before eval_const_expressions, since the latter
1422 : : * would be unable to simplify a top-level AND correctly. Also,
1423 : : * SS_process_sublinks expects explicit-AND format.)
1424 : : */
8098 1425 [ + + ]: 515231 : if (kind == EXPRKIND_QUAL)
1426 : 193220 : expr = (Node *) make_ands_implicit((Expr *) expr);
1427 : :
9298 1428 : 515231 : return expr;
1429 : : }
1430 : :
1431 : : /*
1432 : : * preprocess_qual_conditions
1433 : : * Recursively scan the query's jointree and do subquery_planner's
1434 : : * preprocessing work on each qual condition found therein.
1435 : : */
1436 : : static void
7588 1437 : 726249 : preprocess_qual_conditions(PlannerInfo *root, Node *jtnode)
1438 : : {
9298 1439 [ - + ]: 726249 : if (jtnode == NULL)
9298 tgl@sss.pgh.pa.us 1440 :UBC 0 : return;
9298 tgl@sss.pgh.pa.us 1441 [ + + ]:CBC 726249 : if (IsA(jtnode, RangeTblRef))
1442 : : {
1443 : : /* nothing to do here */
1444 : : }
1445 [ + + ]: 356566 : else if (IsA(jtnode, FromExpr))
1446 : : {
1447 : 295301 : FromExpr *f = (FromExpr *) jtnode;
1448 : : ListCell *l;
1449 : :
1450 [ + + + + : 613443 : foreach(l, f->fromlist)
+ + ]
7588 1451 : 318142 : preprocess_qual_conditions(root, lfirst(l));
1452 : :
1453 : 295301 : f->quals = preprocess_expression(root, f->quals, EXPRKIND_QUAL);
1454 : : }
9298 1455 [ + - ]: 61265 : else if (IsA(jtnode, JoinExpr))
1456 : : {
1457 : 61265 : JoinExpr *j = (JoinExpr *) jtnode;
1458 : :
7588 1459 : 61265 : preprocess_qual_conditions(root, j->larg);
1460 : 61265 : preprocess_qual_conditions(root, j->rarg);
1461 : :
1462 : 61265 : j->quals = preprocess_expression(root, j->quals, EXPRKIND_QUAL);
1463 : : }
1464 : : else
8269 tgl@sss.pgh.pa.us 1465 [ # # ]:UBC 0 : elog(ERROR, "unrecognized node type: %d",
1466 : : (int) nodeTag(jtnode));
1467 : : }
1468 : :
1469 : : /*
1470 : : * preprocess_phv_expression
1471 : : * Do preprocessing on a PlaceHolderVar expression that's been pulled up.
1472 : : *
1473 : : * If a LATERAL subquery references an output of another subquery, and that
1474 : : * output must be wrapped in a PlaceHolderVar because of an intermediate outer
1475 : : * join, then we'll push the PlaceHolderVar expression down into the subquery
1476 : : * and later pull it back up during find_lateral_references, which runs after
1477 : : * subquery_planner has preprocessed all the expressions that were in the
1478 : : * current query level to start with. So we need to preprocess it then.
1479 : : */
1480 : : Expr *
4949 tgl@sss.pgh.pa.us 1481 :CBC 45 : preprocess_phv_expression(PlannerInfo *root, Expr *expr)
1482 : : {
1483 : 45 : return (Expr *) preprocess_expression(root, (Node *) expr, EXPRKIND_PHV);
1484 : : }
1485 : :
1486 : : /*--------------------
1487 : : * grouping_planner
1488 : : * Perform planning steps related to grouping, aggregation, etc.
1489 : : *
1490 : : * This function adds all required top-level processing to the scan/join
1491 : : * Path(s) produced by query_planner.
1492 : : *
1493 : : * tuple_fraction is the fraction of tuples we expect will be retrieved.
1494 : : * tuple_fraction is interpreted as follows:
1495 : : * 0: expect all tuples to be retrieved (normal case)
1496 : : * 0 < tuple_fraction < 1: expect the given fraction of tuples available
1497 : : * from the plan to be retrieved
1498 : : * tuple_fraction >= 1: tuple_fraction is the absolute number of tuples
1499 : : * expected to be retrieved (ie, a LIMIT specification).
1500 : : * setops is used for set operation subqueries to provide the subquery with
1501 : : * the context in which it's being used so that Paths correctly sorted for the
1502 : : * set operation can be generated. NULL when not planning a set operation
1503 : : * child, or when a child of a set op that isn't interested in sorted input.
1504 : : *
1505 : : * Returns nothing; the useful output is in the Paths we attach to the
1506 : : * (UPPERREL_FINAL, NULL) upperrel in *root. In addition,
1507 : : * root->processed_tlist contains the final processed targetlist.
1508 : : *
1509 : : * Note that we have not done set_cheapest() on the final rel; it's convenient
1510 : : * to leave this to the caller.
1511 : : *--------------------
1512 : : */
1513 : : static void
663 rhaas@postgresql.org 1514 : 285577 : grouping_planner(PlannerInfo *root, double tuple_fraction,
1515 : : SetOperationStmt *setops)
1516 : : {
7588 tgl@sss.pgh.pa.us 1517 : 285577 : Query *parse = root->parse;
7172 bruce@momjian.us 1518 : 285577 : int64 offset_est = 0;
1519 : 285577 : int64 count_est = 0;
6890 tgl@sss.pgh.pa.us 1520 : 285577 : double limit_tuples = -1.0;
3656 1521 : 285577 : bool have_postponed_srfs = false;
1522 : : PathTarget *final_target;
1523 : : List *final_targets;
1524 : : List *final_targets_contain_srfs;
1525 : : bool final_target_parallel_safe;
1526 : : RelOptInfo *current_rel;
1527 : : RelOptInfo *final_rel;
1528 : : FinalPathExtraData extra;
1529 : : ListCell *lc;
1530 : :
1531 : : /* Tweak caller-supplied tuple_fraction if have LIMIT/OFFSET */
7514 1532 [ + + + + ]: 285577 : if (parse->limitCount || parse->limitOffset)
1533 : : {
1534 : 2623 : tuple_fraction = preprocess_limit(root, tuple_fraction,
1535 : : &offset_est, &count_est);
1536 : :
1537 : : /*
1538 : : * If we have a known LIMIT, and don't have an unknown OFFSET, we can
1539 : : * estimate the effects of using a bounded sort.
1540 : : */
6890 1541 [ + + + + ]: 2623 : if (count_est > 0 && offset_est >= 0)
1542 : 2337 : limit_tuples = (double) count_est + (double) offset_est;
1543 : : }
1544 : :
1545 : : /* Make tuple_fraction accessible to lower-level routines */
3660 1546 : 285577 : root->tuple_fraction = tuple_fraction;
1547 : :
9292 1548 [ + + ]: 285577 : if (parse->setOperations)
1549 : : {
1550 : : /*
1551 : : * Construct Paths for set operations. The results will not need any
1552 : : * work except perhaps a top-level sort and/or LIMIT. Note that any
1553 : : * special work for recursive unions is the responsibility of
1554 : : * plan_set_operations.
1555 : : */
3660 1556 : 3301 : current_rel = plan_set_operations(root);
1557 : :
1558 : : /*
1559 : : * We should not need to call preprocess_targetlist, since we must be
1560 : : * in a SELECT query node. Instead, use the processed_tlist returned
1561 : : * by plan_set_operations (since this tells whether it returned any
1562 : : * resjunk columns!), and transfer any sort key information from the
1563 : : * original tlist.
1564 : : */
9292 1565 [ - + ]: 3298 : Assert(parse->commandType == CMD_SELECT);
1566 : :
1567 : : /* for safety, copy processed_tlist instead of modifying in-place */
2545 1568 : 3298 : root->processed_tlist =
1569 : 3298 : postprocess_setop_tlist(copyObject(root->processed_tlist),
1570 : : parse->targetList);
1571 : :
1572 : : /* Also extract the PathTarget form of the setop result tlist */
3656 1573 : 3298 : final_target = current_rel->cheapest_total_path->pathtarget;
1574 : :
1575 : : /* And check whether it's parallel safe */
1576 : : final_target_parallel_safe =
2929 rhaas@postgresql.org 1577 : 3298 : is_parallel_safe(root, (Node *) final_target->exprs);
1578 : :
1579 : : /* The setop result tlist couldn't contain any SRFs */
3343 andres@anarazel.de 1580 [ - + ]: 3298 : Assert(!parse->hasTargetSRFs);
1581 : 3298 : final_targets = final_targets_contain_srfs = NIL;
1582 : :
1583 : : /*
1584 : : * Can't handle FOR [KEY] UPDATE/SHARE here (parser should have
1585 : : * checked already, but let's make sure).
1586 : : */
9230 tgl@sss.pgh.pa.us 1587 [ - + ]: 3298 : if (parse->rowMarks)
8269 tgl@sss.pgh.pa.us 1588 [ # # ]:UBC 0 : ereport(ERROR,
1589 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1590 : : /*------
1591 : : translator: %s is a SQL row locking clause such as FOR UPDATE */
1592 : : errmsg("%s is not allowed with UNION/INTERSECT/EXCEPT",
1593 : : LCS_asString(linitial_node(RowMarkClause,
1594 : : parse->rowMarks)->strength))));
1595 : :
1596 : : /*
1597 : : * Calculate pathkeys that represent result ordering requirements
1598 : : */
6436 tgl@sss.pgh.pa.us 1599 [ - + ]:CBC 3298 : Assert(parse->distinctClause == NIL);
6431 1600 : 3298 : root->sort_pathkeys = make_pathkeys_for_sortclauses(root,
1601 : : parse->sortClause,
1602 : : root->processed_tlist);
1603 : : }
1604 : : else
1605 : : {
1606 : : /* No set operations, do regular planning */
1607 : : PathTarget *sort_input_target;
1608 : : List *sort_input_targets;
1609 : : List *sort_input_targets_contain_srfs;
1610 : : bool sort_input_target_parallel_safe;
1611 : : PathTarget *grouping_target;
1612 : : List *grouping_targets;
1613 : : List *grouping_targets_contain_srfs;
1614 : : bool grouping_target_parallel_safe;
1615 : : PathTarget *scanjoin_target;
1616 : : List *scanjoin_targets;
1617 : : List *scanjoin_targets_contain_srfs;
1618 : : bool scanjoin_target_parallel_safe;
1619 : : bool scanjoin_target_same_exprs;
1620 : : bool have_grouping;
6286 1621 : 282276 : WindowFuncLists *wflists = NULL;
1622 : 282276 : List *activeWindows = NIL;
3275 rhodiumtoad@postgres 1623 : 282276 : grouping_sets_data *gset_data = NULL;
1624 : : standard_qp_extra qp_extra;
1625 : :
1626 : : /* A recursive query should always have setOperations */
6371 tgl@sss.pgh.pa.us 1627 [ - + ]: 282276 : Assert(!root->hasRecursion);
1628 : :
1629 : : /* Preprocess grouping sets and GROUP BY clause, if any */
3956 andres@anarazel.de 1630 [ + + ]: 282276 : if (parse->groupingSets)
1631 : : {
3275 rhodiumtoad@postgres 1632 : 519 : gset_data = preprocess_grouping_sets(root);
1633 : : }
1152 tgl@sss.pgh.pa.us 1634 [ + + ]: 281757 : else if (parse->groupClause)
1635 : : {
1636 : : /* Preprocess regular GROUP BY clause, if any */
647 akorotkov@postgresql 1637 : 2077 : root->processed_groupClause = preprocess_groupclause(root, NIL);
1638 : : }
1639 : :
1640 : : /*
1641 : : * Preprocess targetlist. Note that much of the remaining planning
1642 : : * work will be done with the PathTarget representation of tlists, but
1643 : : * we must also maintain the full representation of the final tlist so
1644 : : * that we can transfer its decoration (resnames etc) to the topmost
1645 : : * tlist of the finished Plan. This is kept in processed_tlist.
1646 : : */
1810 tgl@sss.pgh.pa.us 1647 : 282273 : preprocess_targetlist(root);
1648 : :
1649 : : /*
1650 : : * Mark all the aggregates with resolved aggtranstypes, and detect
1651 : : * aggregates that are duplicates or can share transition state. We
1652 : : * must do this before slicing and dicing the tlist into various
1653 : : * pathtargets, else some copies of the Aggref nodes might escape
1654 : : * being marked.
1655 : : */
3543 1656 [ + + ]: 282273 : if (parse->hasAggs)
1657 : : {
1937 heikki.linnakangas@i 1658 : 23117 : preprocess_aggrefs(root, (Node *) root->processed_tlist);
1659 : 23117 : preprocess_aggrefs(root, (Node *) parse->havingQual);
1660 : : }
1661 : :
1662 : : /*
1663 : : * Locate any window functions in the tlist. (We don't need to look
1664 : : * anywhere else, since expressions used in ORDER BY will be in there
1665 : : * too.) Note that they could all have been eliminated by constant
1666 : : * folding, in which case we don't need to do any more work.
1667 : : */
6286 tgl@sss.pgh.pa.us 1668 [ + + ]: 282273 : if (parse->hasWindowFuncs)
1669 : : {
2545 1670 : 1341 : wflists = find_window_functions((Node *) root->processed_tlist,
6286 1671 : 1341 : list_length(parse->windowClause));
1672 [ + + ]: 1341 : if (wflists->numWindowFuncs > 0)
1673 : : {
1674 : : /*
1675 : : * See if any modifications can be made to each WindowClause
1676 : : * to allow the executor to execute the WindowFuncs more
1677 : : * quickly.
1678 : : */
1178 drowley@postgresql.o 1679 : 1338 : optimize_window_clauses(root, wflists);
1680 : :
1681 : : /* Extract the list of windows actually in use. */
6286 tgl@sss.pgh.pa.us 1682 : 1338 : activeWindows = select_active_windows(root, wflists);
1683 : :
1684 : : /* Make sure they all have names, for EXPLAIN's use. */
369 1685 : 1338 : name_active_windows(activeWindows);
1686 : : }
1687 : : else
6286 1688 : 3 : parse->hasWindowFuncs = false;
1689 : : }
1690 : :
1691 : : /*
1692 : : * Preprocess MIN/MAX aggregates, if any. Note: be careful about
1693 : : * adding logic between here and the query_planner() call. Anything
1694 : : * that is needed in MIN/MAX-optimizable cases will have to be
1695 : : * duplicated in planagg.c.
1696 : : */
5610 1697 [ + + ]: 282273 : if (parse->hasAggs)
2545 1698 : 23117 : preprocess_minmax_aggregates(root);
1699 : :
1700 : : /*
1701 : : * Figure out whether there's a hard limit on the number of rows that
1702 : : * query_planner's result subplan needs to return. Even if we know a
1703 : : * hard limit overall, it doesn't apply if the query has any
1704 : : * grouping/aggregation operations, or SRFs in the tlist.
1705 : : */
5596 1706 [ + + ]: 282273 : if (parse->groupClause ||
3956 andres@anarazel.de 1707 [ + + ]: 279719 : parse->groupingSets ||
5596 tgl@sss.pgh.pa.us 1708 [ + + ]: 279680 : parse->distinctClause ||
1709 [ + + ]: 278091 : parse->hasAggs ||
1710 [ + + ]: 257198 : parse->hasWindowFuncs ||
3470 1711 [ + + ]: 255932 : parse->hasTargetSRFs ||
5596 1712 [ + + ]: 249677 : root->hasHavingQual)
4605 1713 : 32608 : root->limit_tuples = -1.0;
1714 : : else
1715 : 249665 : root->limit_tuples = limit_tuples;
1716 : :
1717 : : /* Set up data needed by standard_qp_callback */
4703 1718 : 282273 : qp_extra.activeWindows = activeWindows;
1152 1719 : 282273 : qp_extra.gset_data = gset_data;
1720 : :
1721 : : /*
1722 : : * If we're a subquery for a set operation, store the SetOperationStmt
1723 : : * in qp_extra.
1724 : : */
663 rhaas@postgresql.org 1725 : 282273 : qp_extra.setop = setops;
1726 : :
1727 : : /*
1728 : : * Generate the best unsorted and presorted paths for the scan/join
1729 : : * portion of this Query, ie the processing represented by the
1730 : : * FROM/WHERE clauses. (Note there may not be any presorted paths.)
1731 : : * We also generate (in standard_qp_callback) pathkey representations
1732 : : * of the query's sort clause, distinct clause, etc.
1733 : : */
2545 tgl@sss.pgh.pa.us 1734 : 282273 : current_rel = query_planner(root, standard_qp_callback, &qp_extra);
1735 : :
1736 : : /*
1737 : : * Convert the query's result tlist into PathTarget format.
1738 : : *
1739 : : * Note: this cannot be done before query_planner() has performed
1740 : : * appendrel expansion, because that might add resjunk entries to
1741 : : * root->processed_tlist. Waiting till afterwards is also helpful
1742 : : * because the target width estimates can use per-Var width numbers
1743 : : * that were obtained within query_planner().
1744 : : */
1745 : 282246 : final_target = create_pathtarget(root, root->processed_tlist);
1746 : : final_target_parallel_safe =
2929 rhaas@postgresql.org 1747 : 282246 : is_parallel_safe(root, (Node *) final_target->exprs);
1748 : :
1749 : : /*
1750 : : * If ORDER BY was given, consider whether we should use a post-sort
1751 : : * projection, and compute the adjusted target for preceding steps if
1752 : : * so.
1753 : : */
3656 tgl@sss.pgh.pa.us 1754 [ + + ]: 282246 : if (parse->sortClause)
1755 : : {
1756 : 39353 : sort_input_target = make_sort_input_target(root,
1757 : : final_target,
1758 : : &have_postponed_srfs);
1759 : : sort_input_target_parallel_safe =
2929 rhaas@postgresql.org 1760 : 39353 : is_parallel_safe(root, (Node *) sort_input_target->exprs);
1761 : : }
1762 : : else
1763 : : {
3656 tgl@sss.pgh.pa.us 1764 : 242893 : sort_input_target = final_target;
2929 rhaas@postgresql.org 1765 : 242893 : sort_input_target_parallel_safe = final_target_parallel_safe;
1766 : : }
1767 : :
1768 : : /*
1769 : : * If we have window functions to deal with, the output from any
1770 : : * grouping step needs to be what the window functions want;
1771 : : * otherwise, it should be sort_input_target.
1772 : : */
3658 tgl@sss.pgh.pa.us 1773 [ + + ]: 282246 : if (activeWindows)
1774 : : {
1775 : 1338 : grouping_target = make_window_input_target(root,
1776 : : final_target,
1777 : : activeWindows);
1778 : : grouping_target_parallel_safe =
2929 rhaas@postgresql.org 1779 : 1338 : is_parallel_safe(root, (Node *) grouping_target->exprs);
1780 : : }
1781 : : else
1782 : : {
3656 tgl@sss.pgh.pa.us 1783 : 280908 : grouping_target = sort_input_target;
2929 rhaas@postgresql.org 1784 : 280908 : grouping_target_parallel_safe = sort_input_target_parallel_safe;
1785 : : }
1786 : :
1787 : : /*
1788 : : * If we have grouping or aggregation to do, the topmost scan/join
1789 : : * plan node must emit what the grouping step wants; otherwise, it
1790 : : * should emit grouping_target.
1791 : : */
3658 tgl@sss.pgh.pa.us 1792 [ + + ]: 279692 : have_grouping = (parse->groupClause || parse->groupingSets ||
1793 [ + + + + : 561938 : parse->hasAggs || root->hasHavingQual);
+ + ]
1794 [ + + ]: 282246 : if (have_grouping)
1795 : : {
3656 1796 : 23517 : scanjoin_target = make_group_input_target(root, final_target);
1797 : : scanjoin_target_parallel_safe =
2560 efujita@postgresql.o 1798 : 23517 : is_parallel_safe(root, (Node *) scanjoin_target->exprs);
1799 : : }
1800 : : else
1801 : : {
3658 tgl@sss.pgh.pa.us 1802 : 258729 : scanjoin_target = grouping_target;
2929 rhaas@postgresql.org 1803 : 258729 : scanjoin_target_parallel_safe = grouping_target_parallel_safe;
1804 : : }
1805 : :
1806 : : /*
1807 : : * If there are any SRFs in the targetlist, we must separate each of
1808 : : * these PathTargets into SRF-computing and SRF-free targets. Replace
1809 : : * each of the named targets with a SRF-free version, and remember the
1810 : : * list of additional projection steps we need to add afterwards.
1811 : : */
3343 andres@anarazel.de 1812 [ + + ]: 282246 : if (parse->hasTargetSRFs)
1813 : : {
1814 : : /* final_target doesn't recompute any SRFs in sort_input_target */
1815 : 6519 : split_pathtarget_at_srfs(root, final_target, sort_input_target,
1816 : : &final_targets,
1817 : : &final_targets_contain_srfs);
3113 tgl@sss.pgh.pa.us 1818 : 6519 : final_target = linitial_node(PathTarget, final_targets);
3343 andres@anarazel.de 1819 [ - + ]: 6519 : Assert(!linitial_int(final_targets_contain_srfs));
1820 : : /* likewise for sort_input_target vs. grouping_target */
1821 : 6519 : split_pathtarget_at_srfs(root, sort_input_target, grouping_target,
1822 : : &sort_input_targets,
1823 : : &sort_input_targets_contain_srfs);
3113 tgl@sss.pgh.pa.us 1824 : 6519 : sort_input_target = linitial_node(PathTarget, sort_input_targets);
3343 andres@anarazel.de 1825 [ - + ]: 6519 : Assert(!linitial_int(sort_input_targets_contain_srfs));
1826 : : /* likewise for grouping_target vs. scanjoin_target */
80 rguo@postgresql.org 1827 : 6519 : split_pathtarget_at_srfs_grouping(root,
1828 : : grouping_target, scanjoin_target,
1829 : : &grouping_targets,
1830 : : &grouping_targets_contain_srfs);
3113 tgl@sss.pgh.pa.us 1831 : 6519 : grouping_target = linitial_node(PathTarget, grouping_targets);
3343 andres@anarazel.de 1832 [ - + ]: 6519 : Assert(!linitial_int(grouping_targets_contain_srfs));
1833 : : /* scanjoin_target will not have any SRFs precomputed for it */
1834 : 6519 : split_pathtarget_at_srfs(root, scanjoin_target, NULL,
1835 : : &scanjoin_targets,
1836 : : &scanjoin_targets_contain_srfs);
3113 tgl@sss.pgh.pa.us 1837 : 6519 : scanjoin_target = linitial_node(PathTarget, scanjoin_targets);
3343 andres@anarazel.de 1838 [ - + ]: 6519 : Assert(!linitial_int(scanjoin_targets_contain_srfs));
1839 : : }
1840 : : else
1841 : : {
1842 : : /* initialize lists; for most of these, dummy values are OK */
1843 : 275727 : final_targets = final_targets_contain_srfs = NIL;
1844 : 275727 : sort_input_targets = sort_input_targets_contain_srfs = NIL;
1845 : 275727 : grouping_targets = grouping_targets_contain_srfs = NIL;
2908 rhaas@postgresql.org 1846 : 275727 : scanjoin_targets = list_make1(scanjoin_target);
1847 : 275727 : scanjoin_targets_contain_srfs = NIL;
1848 : : }
1849 : :
1850 : : /* Apply scan/join target. */
1851 : 282246 : scanjoin_target_same_exprs = list_length(scanjoin_targets) == 1
1852 [ + + + + ]: 282246 : && equal(scanjoin_target->exprs, current_rel->reltarget->exprs);
1853 : 282246 : apply_scanjoin_target_to_paths(root, current_rel, scanjoin_targets,
1854 : : scanjoin_targets_contain_srfs,
1855 : : scanjoin_target_parallel_safe,
1856 : : scanjoin_target_same_exprs);
1857 : :
1858 : : /*
1859 : : * Save the various upper-rel PathTargets we just computed into
1860 : : * root->upper_targets[]. The core code doesn't use this, but it
1861 : : * provides a convenient place for extensions to get at the info. For
1862 : : * consistency, we save all the intermediate targets, even though some
1863 : : * of the corresponding upperrels might not be needed for this query.
1864 : : */
3653 tgl@sss.pgh.pa.us 1865 : 282246 : root->upper_targets[UPPERREL_FINAL] = final_target;
2582 efujita@postgresql.o 1866 : 282246 : root->upper_targets[UPPERREL_ORDERED] = final_target;
1867 : 282246 : root->upper_targets[UPPERREL_DISTINCT] = sort_input_target;
767 drowley@postgresql.o 1868 : 282246 : root->upper_targets[UPPERREL_PARTIAL_DISTINCT] = sort_input_target;
3653 tgl@sss.pgh.pa.us 1869 : 282246 : root->upper_targets[UPPERREL_WINDOW] = sort_input_target;
1870 : 282246 : root->upper_targets[UPPERREL_GROUP_AGG] = grouping_target;
1871 : :
1872 : : /*
1873 : : * If we have grouping and/or aggregation, consider ways to implement
1874 : : * that. We build a new upperrel representing the output of this
1875 : : * phase.
1876 : : */
3658 1877 [ + + ]: 282246 : if (have_grouping)
1878 : : {
3660 1879 : 23517 : current_rel = create_grouping_paths(root,
1880 : : current_rel,
1881 : : grouping_target,
1882 : : grouping_target_parallel_safe,
1883 : : gset_data);
1884 : : /* Fix things up if grouping_target contains SRFs */
3343 andres@anarazel.de 1885 [ + + ]: 23514 : if (parse->hasTargetSRFs)
1886 : 243 : adjust_paths_for_srfs(root, current_rel,
1887 : : grouping_targets,
1888 : : grouping_targets_contain_srfs);
1889 : : }
1890 : :
1891 : : /*
1892 : : * If we have window functions, consider ways to implement those. We
1893 : : * build a new upperrel representing the output of this phase.
1894 : : */
3660 tgl@sss.pgh.pa.us 1895 [ + + ]: 282243 : if (activeWindows)
1896 : : {
1897 : 1338 : current_rel = create_window_paths(root,
1898 : : current_rel,
1899 : : grouping_target,
1900 : : sort_input_target,
1901 : : sort_input_target_parallel_safe,
1902 : : wflists,
1903 : : activeWindows);
1904 : : /* Fix things up if sort_input_target contains SRFs */
3343 andres@anarazel.de 1905 [ + + ]: 1338 : if (parse->hasTargetSRFs)
1906 : 6 : adjust_paths_for_srfs(root, current_rel,
1907 : : sort_input_targets,
1908 : : sort_input_targets_contain_srfs);
1909 : : }
1910 : :
1911 : : /*
1912 : : * If there is a DISTINCT clause, consider ways to implement that. We
1913 : : * build a new upperrel representing the output of this phase.
1914 : : */
3660 tgl@sss.pgh.pa.us 1915 [ + + ]: 282243 : if (parse->distinctClause)
1916 : : {
1917 : 1606 : current_rel = create_distinct_paths(root,
1918 : : current_rel,
1919 : : sort_input_target);
1920 : : }
1921 : : } /* end of if (setOperations) */
1922 : :
1923 : : /*
1924 : : * If ORDER BY was given, consider ways to implement that, and generate a
1925 : : * new upperrel containing only paths that emit the correct ordering and
1926 : : * project the correct final_target. We can apply the original
1927 : : * limit_tuples limit in sort costing here, but only if there are no
1928 : : * postponed SRFs.
1929 : : */
1930 [ + + ]: 285541 : if (parse->sortClause)
1931 : : {
1932 [ + + ]: 41423 : current_rel = create_ordered_paths(root,
1933 : : current_rel,
1934 : : final_target,
1935 : : final_target_parallel_safe,
1936 : : have_postponed_srfs ? -1.0 :
1937 : : limit_tuples);
1938 : : /* Fix things up if final_target contains SRFs */
3343 andres@anarazel.de 1939 [ + + ]: 41423 : if (parse->hasTargetSRFs)
1940 : 110 : adjust_paths_for_srfs(root, current_rel,
1941 : : final_targets,
1942 : : final_targets_contain_srfs);
1943 : : }
1944 : :
1945 : : /*
1946 : : * Now we are prepared to build the final-output upperrel.
1947 : : */
3660 tgl@sss.pgh.pa.us 1948 : 285541 : final_rel = fetch_upper_rel(root, UPPERREL_FINAL, NULL);
1949 : :
1950 : : /*
1951 : : * If the input rel is marked consider_parallel and there's nothing that's
1952 : : * not parallel-safe in the LIMIT clause, then the final_rel can be marked
1953 : : * consider_parallel as well. Note that if the query has rowMarks or is
1954 : : * not a SELECT, consider_parallel will be false for every relation in the
1955 : : * query.
1956 : : */
3544 rhaas@postgresql.org 1957 [ + + + + ]: 384743 : if (current_rel->consider_parallel &&
3495 tgl@sss.pgh.pa.us 1958 [ + + ]: 198392 : is_parallel_safe(root, parse->limitOffset) &&
1959 : 99190 : is_parallel_safe(root, parse->limitCount))
3544 rhaas@postgresql.org 1960 : 99187 : final_rel->consider_parallel = true;
1961 : :
1962 : : /*
1963 : : * If the current_rel belongs to a single FDW, so does the final_rel.
1964 : : */
tgl@sss.pgh.pa.us 1965 : 285541 : final_rel->serverid = current_rel->serverid;
3530 1966 : 285541 : final_rel->userid = current_rel->userid;
1967 : 285541 : final_rel->useridiscurrent = current_rel->useridiscurrent;
3544 1968 : 285541 : final_rel->fdwroutine = current_rel->fdwroutine;
1969 : :
1970 : : /*
1971 : : * Generate paths for the final_rel. Insert all surviving paths, with
1972 : : * LockRows, Limit, and/or ModifyTable steps added if needed.
1973 : : */
3660 1974 [ + - + + : 581824 : foreach(lc, current_rel->pathlist)
+ + ]
1975 : : {
1976 : 296283 : Path *path = (Path *) lfirst(lc);
1977 : :
1978 : : /*
1979 : : * If there is a FOR [KEY] UPDATE/SHARE clause, add the LockRows node.
1980 : : * (Note: we intentionally test parse->rowMarks not root->rowMarks
1981 : : * here. If there are only non-locking rowmarks, they should be
1982 : : * handled by the ModifyTable node instead. However, root->rowMarks
1983 : : * is what goes into the LockRows node.)
1984 : : */
1985 [ + + ]: 296283 : if (parse->rowMarks)
1986 : : {
1987 : 7063 : path = (Path *) create_lockrows_path(root, final_rel, path,
1988 : : root->rowMarks,
1989 : : assign_special_exec_param(root));
1990 : : }
1991 : :
1992 : : /*
1993 : : * If there is a LIMIT/OFFSET clause, add the LIMIT node.
1994 : : */
1995 [ + + ]: 296283 : if (limit_needed(parse))
1996 : : {
1997 : 3113 : path = (Path *) create_limit_path(root, final_rel, path,
1998 : : parse->limitOffset,
1999 : : parse->limitCount,
2000 : : parse->limitOption,
2001 : : offset_est, count_est);
2002 : : }
2003 : :
2004 : : /*
2005 : : * If this is an INSERT/UPDATE/DELETE/MERGE, add the ModifyTable node.
2006 : : */
1810 2007 [ + + ]: 296283 : if (parse->commandType != CMD_SELECT)
2008 : : {
2009 : : Index rootRelation;
2010 : 43579 : List *resultRelations = NIL;
2011 : 43579 : List *updateColnosLists = NIL;
2012 : 43579 : List *withCheckOptionLists = NIL;
2013 : 43579 : List *returningLists = NIL;
1448 alvherre@alvh.no-ip. 2014 : 43579 : List *mergeActionLists = NIL;
715 dean.a.rasheed@gmail 2015 : 43579 : List *mergeJoinConditions = NIL;
2016 : : List *rowMarks;
2017 : :
1810 tgl@sss.pgh.pa.us 2018 [ + + ]: 43579 : if (bms_membership(root->all_result_relids) == BMS_MULTIPLE)
2019 : : {
2020 : : /* Inherited UPDATE/DELETE/MERGE */
2021 : 1470 : RelOptInfo *top_result_rel = find_base_rel(root,
2022 : : parse->resultRelation);
2023 : 1470 : int resultRelation = -1;
2024 : :
2025 : : /* Pass the root result rel forward to the executor. */
873 2026 : 1470 : rootRelation = parse->resultRelation;
2027 : :
2028 : : /* Add only leaf children to ModifyTable. */
1810 2029 : 4270 : while ((resultRelation = bms_next_member(root->leaf_result_relids,
2030 [ + + ]: 4270 : resultRelation)) >= 0)
2031 : : {
2032 : 2800 : RelOptInfo *this_result_rel = find_base_rel(root,
2033 : : resultRelation);
2034 : :
2035 : : /*
2036 : : * Also exclude any leaf rels that have turned dummy since
2037 : : * being added to the list, for example, by being excluded
2038 : : * by constraint exclusion.
2039 : : */
2040 [ + + ]: 2800 : if (IS_DUMMY_REL(this_result_rel))
2041 : 93 : continue;
2042 : :
2043 : : /* Build per-target-rel lists needed by ModifyTable */
2044 : 2707 : resultRelations = lappend_int(resultRelations,
2045 : : resultRelation);
2046 [ + + ]: 2707 : if (parse->commandType == CMD_UPDATE)
2047 : : {
2048 : 1851 : List *update_colnos = root->update_colnos;
2049 : :
2050 [ + - ]: 1851 : if (this_result_rel != top_result_rel)
2051 : : update_colnos =
2052 : 1851 : adjust_inherited_attnums_multilevel(root,
2053 : : update_colnos,
2054 : : this_result_rel->relid,
2055 : : top_result_rel->relid);
2056 : 1851 : updateColnosLists = lappend(updateColnosLists,
2057 : : update_colnos);
2058 : : }
2059 [ + + ]: 2707 : if (parse->withCheckOptions)
2060 : : {
2061 : 252 : List *withCheckOptions = parse->withCheckOptions;
2062 : :
2063 [ + - ]: 252 : if (this_result_rel != top_result_rel)
2064 : : withCheckOptions = (List *)
2065 : 252 : adjust_appendrel_attrs_multilevel(root,
2066 : : (Node *) withCheckOptions,
2067 : : this_result_rel,
2068 : : top_result_rel);
2069 : 252 : withCheckOptionLists = lappend(withCheckOptionLists,
2070 : : withCheckOptions);
2071 : : }
2072 [ + + ]: 2707 : if (parse->returningList)
2073 : : {
2074 : 423 : List *returningList = parse->returningList;
2075 : :
2076 [ + - ]: 423 : if (this_result_rel != top_result_rel)
2077 : : returningList = (List *)
2078 : 423 : adjust_appendrel_attrs_multilevel(root,
2079 : : (Node *) returningList,
2080 : : this_result_rel,
2081 : : top_result_rel);
2082 : 423 : returningLists = lappend(returningLists,
2083 : : returningList);
2084 : : }
1448 alvherre@alvh.no-ip. 2085 [ + + ]: 2707 : if (parse->mergeActionList)
2086 : : {
2087 : : ListCell *l;
2088 : 271 : List *mergeActionList = NIL;
2089 : :
2090 : : /*
2091 : : * Copy MergeActions and translate stuff that
2092 : : * references attribute numbers.
2093 : : */
2094 [ + - + + : 846 : foreach(l, parse->mergeActionList)
+ + ]
2095 : : {
2096 : 575 : MergeAction *action = lfirst(l),
2097 : 575 : *leaf_action = copyObject(action);
2098 : :
2099 : 575 : leaf_action->qual =
2100 : 575 : adjust_appendrel_attrs_multilevel(root,
2101 : : (Node *) action->qual,
2102 : : this_result_rel,
2103 : : top_result_rel);
2104 : 575 : leaf_action->targetList = (List *)
2105 : 575 : adjust_appendrel_attrs_multilevel(root,
2106 : 575 : (Node *) action->targetList,
2107 : : this_result_rel,
2108 : : top_result_rel);
2109 [ + + ]: 575 : if (leaf_action->commandType == CMD_UPDATE)
2110 : 321 : leaf_action->updateColnos =
2111 : 321 : adjust_inherited_attnums_multilevel(root,
2112 : : action->updateColnos,
2113 : : this_result_rel->relid,
2114 : : top_result_rel->relid);
2115 : 575 : mergeActionList = lappend(mergeActionList,
2116 : : leaf_action);
2117 : : }
2118 : :
2119 : 271 : mergeActionLists = lappend(mergeActionLists,
2120 : : mergeActionList);
2121 : : }
715 dean.a.rasheed@gmail 2122 [ + + ]: 2707 : if (parse->commandType == CMD_MERGE)
2123 : : {
2124 : 271 : Node *mergeJoinCondition = parse->mergeJoinCondition;
2125 : :
2126 [ + - ]: 271 : if (this_result_rel != top_result_rel)
2127 : : mergeJoinCondition =
2128 : 271 : adjust_appendrel_attrs_multilevel(root,
2129 : : mergeJoinCondition,
2130 : : this_result_rel,
2131 : : top_result_rel);
2132 : 271 : mergeJoinConditions = lappend(mergeJoinConditions,
2133 : : mergeJoinCondition);
2134 : : }
2135 : : }
2136 : :
1810 tgl@sss.pgh.pa.us 2137 [ + + ]: 1470 : if (resultRelations == NIL)
2138 : : {
2139 : : /*
2140 : : * We managed to exclude every child rel, so generate a
2141 : : * dummy one-relation plan using info for the top target
2142 : : * rel (even though that may not be a leaf target).
2143 : : * Although it's clear that no data will be updated or
2144 : : * deleted, we still need to have a ModifyTable node so
2145 : : * that any statement triggers will be executed. (This
2146 : : * could be cleaner if we fixed nodeModifyTable.c to allow
2147 : : * zero target relations, but that probably wouldn't be a
2148 : : * net win.)
2149 : : */
2150 : 18 : resultRelations = list_make1_int(parse->resultRelation);
2151 [ + + ]: 18 : if (parse->commandType == CMD_UPDATE)
2152 : 16 : updateColnosLists = list_make1(root->update_colnos);
2153 [ - + ]: 18 : if (parse->withCheckOptions)
1810 tgl@sss.pgh.pa.us 2154 :UBC 0 : withCheckOptionLists = list_make1(parse->withCheckOptions);
1810 tgl@sss.pgh.pa.us 2155 [ + + ]:CBC 18 : if (parse->returningList)
2156 : 9 : returningLists = list_make1(parse->returningList);
1448 alvherre@alvh.no-ip. 2157 [ + + ]: 18 : if (parse->mergeActionList)
2158 : 1 : mergeActionLists = list_make1(parse->mergeActionList);
715 dean.a.rasheed@gmail 2159 [ + + ]: 18 : if (parse->commandType == CMD_MERGE)
2160 : 1 : mergeJoinConditions = list_make1(parse->mergeJoinCondition);
2161 : : }
2162 : : }
2163 : : else
2164 : : {
2165 : : /* Single-relation INSERT/UPDATE/DELETE/MERGE. */
873 tgl@sss.pgh.pa.us 2166 : 42109 : rootRelation = 0; /* there's no separate root rel */
1810 2167 : 42109 : resultRelations = list_make1_int(parse->resultRelation);
2168 [ + + ]: 42109 : if (parse->commandType == CMD_UPDATE)
2169 : 6350 : updateColnosLists = list_make1(root->update_colnos);
2170 [ + + ]: 42109 : if (parse->withCheckOptions)
2171 : 547 : withCheckOptionLists = list_make1(parse->withCheckOptions);
2172 [ + + ]: 42109 : if (parse->returningList)
2173 : 1474 : returningLists = list_make1(parse->returningList);
1448 alvherre@alvh.no-ip. 2174 [ + + ]: 42109 : if (parse->mergeActionList)
2175 : 803 : mergeActionLists = list_make1(parse->mergeActionList);
715 dean.a.rasheed@gmail 2176 [ + + ]: 42109 : if (parse->commandType == CMD_MERGE)
2177 : 803 : mergeJoinConditions = list_make1(parse->mergeJoinCondition);
2178 : : }
2179 : :
2180 : : /*
2181 : : * If there was a FOR [KEY] UPDATE/SHARE clause, the LockRows node
2182 : : * will have dealt with fetching non-locked marked rows, else we
2183 : : * need to have ModifyTable do that.
2184 : : */
3660 tgl@sss.pgh.pa.us 2185 [ - + ]: 43579 : if (parse->rowMarks)
3660 tgl@sss.pgh.pa.us 2186 :UBC 0 : rowMarks = NIL;
2187 : : else
3660 tgl@sss.pgh.pa.us 2188 :CBC 43579 : rowMarks = root->rowMarks;
2189 : :
2190 : : path = (Path *)
2191 : 43579 : create_modifytable_path(root, final_rel,
2192 : : path,
2193 : : parse->commandType,
2194 : 43579 : parse->canSetTag,
2195 : 43579 : parse->resultRelation,
2196 : : rootRelation,
2197 : : resultRelations,
2198 : : updateColnosLists,
2199 : : withCheckOptionLists,
2200 : : returningLists,
2201 : : rowMarks,
2202 : : parse->onConflict,
2203 : : mergeActionLists,
2204 : : mergeJoinConditions,
2205 : : assign_special_exec_param(root));
2206 : : }
2207 : :
2208 : : /* And shove it into final_rel */
2209 : 296283 : add_path(final_rel, path);
2210 : : }
2211 : :
2212 : : /*
2213 : : * Generate partial paths for final_rel, too, if outer query levels might
2214 : : * be able to make use of them.
2215 : : */
2924 rhaas@postgresql.org 2216 [ + + + + ]: 285541 : if (final_rel->consider_parallel && root->query_level > 1 &&
2217 [ + + ]: 17603 : !limit_needed(parse))
2218 : : {
2219 [ + - - + ]: 17511 : Assert(!parse->rowMarks && parse->commandType == CMD_SELECT);
2220 [ + + + + : 17573 : foreach(lc, current_rel->partial_pathlist)
+ + ]
2221 : : {
2222 : 62 : Path *partial_path = (Path *) lfirst(lc);
2223 : :
2224 : 62 : add_partial_path(final_rel, partial_path);
2225 : : }
2226 : : }
2227 : :
2539 efujita@postgresql.o 2228 : 285541 : extra.limit_needed = limit_needed(parse);
2229 : 285541 : extra.limit_tuples = limit_tuples;
2230 : 285541 : extra.count_est = count_est;
2231 : 285541 : extra.offset_est = offset_est;
2232 : :
2233 : : /*
2234 : : * If there is an FDW that's responsible for all baserels of the query,
2235 : : * let it consider adding ForeignPaths.
2236 : : */
3544 tgl@sss.pgh.pa.us 2237 [ + + ]: 285541 : if (final_rel->fdwroutine &&
2238 [ + + ]: 637 : final_rel->fdwroutine->GetForeignUpperPaths)
2239 : 601 : final_rel->fdwroutine->GetForeignUpperPaths(root, UPPERREL_FINAL,
2240 : : current_rel, final_rel,
2241 : : &extra);
2242 : :
2243 : : /* Let extensions possibly add some more paths */
3624 2244 [ - + ]: 285541 : if (create_upper_paths_hook)
3624 tgl@sss.pgh.pa.us 2245 :UBC 0 : (*create_upper_paths_hook) (root, UPPERREL_FINAL,
2246 : : current_rel, final_rel, &extra);
2247 : :
2248 : : /* Note: currently, we leave it to callers to do set_cheapest() */
3660 tgl@sss.pgh.pa.us 2249 :CBC 285541 : }
2250 : :
2251 : : /*
2252 : : * Do preprocessing for groupingSets clause and related data.
2253 : : *
2254 : : * We expect that parse->groupingSets has already been expanded into a flat
2255 : : * list of grouping sets (that is, just integer Lists of ressortgroupref
2256 : : * numbers) by expand_grouping_sets(). This function handles the preliminary
2257 : : * steps of organizing the grouping sets into lists of rollups, and preparing
2258 : : * annotations which will later be filled in with size estimates.
2259 : : */
2260 : : static grouping_sets_data *
3275 rhodiumtoad@postgres 2261 : 519 : preprocess_grouping_sets(PlannerInfo *root)
2262 : : {
2263 : 519 : Query *parse = root->parse;
2264 : : List *sets;
2265 : 519 : int maxref = 0;
2266 : : ListCell *lc_set;
95 michael@paquier.xyz 2267 :GNC 519 : grouping_sets_data *gd = palloc0_object(grouping_sets_data);
2268 : :
2269 : : /*
2270 : : * We don't currently make any attempt to optimize the groupClause when
2271 : : * there are grouping sets, so just duplicate it in processed_groupClause.
2272 : : */
1152 tgl@sss.pgh.pa.us 2273 :CBC 519 : root->processed_groupClause = parse->groupClause;
2274 : :
2275 : : /* Detect unhashable and unsortable grouping expressions */
145 rguo@postgresql.org 2276 : 519 : gd->any_hashable = false;
2277 : 519 : gd->unhashable_refs = NULL;
2278 : 519 : gd->unsortable_refs = NULL;
2279 : 519 : gd->unsortable_sets = NIL;
2280 : :
3275 rhodiumtoad@postgres 2281 [ + + ]: 519 : if (parse->groupClause)
2282 : : {
2283 : : ListCell *lc;
2284 : :
2285 [ + - + + : 1517 : foreach(lc, parse->groupClause)
+ + ]
2286 : : {
3113 tgl@sss.pgh.pa.us 2287 : 1037 : SortGroupClause *gc = lfirst_node(SortGroupClause, lc);
3275 rhodiumtoad@postgres 2288 : 1037 : Index ref = gc->tleSortGroupRef;
2289 : :
2290 [ + + ]: 1037 : if (ref > maxref)
2291 : 1013 : maxref = ref;
2292 : :
2293 [ + + ]: 1037 : if (!gc->hashable)
2294 : 15 : gd->unhashable_refs = bms_add_member(gd->unhashable_refs, ref);
2295 : :
2296 [ + + ]: 1037 : if (!OidIsValid(gc->sortop))
2297 : 21 : gd->unsortable_refs = bms_add_member(gd->unsortable_refs, ref);
2298 : : }
2299 : : }
2300 : :
2301 : : /* Allocate workspace array for remapping */
2302 : 519 : gd->tleref_to_colnum_map = (int *) palloc((maxref + 1) * sizeof(int));
2303 : :
2304 : : /*
2305 : : * If we have any unsortable sets, we must extract them before trying to
2306 : : * prepare rollups. Unsortable sets don't go through
2307 : : * reorder_grouping_sets, so we must apply the GroupingSetData annotation
2308 : : * here.
2309 : : */
2310 [ + + ]: 519 : if (!bms_is_empty(gd->unsortable_refs))
2311 : : {
2312 : 21 : List *sortable_sets = NIL;
2313 : : ListCell *lc;
2314 : :
2315 [ + - + + : 63 : foreach(lc, parse->groupingSets)
+ + ]
2316 : : {
3113 tgl@sss.pgh.pa.us 2317 : 45 : List *gset = (List *) lfirst(lc);
2318 : :
3275 rhodiumtoad@postgres 2319 [ + + ]: 45 : if (bms_overlap_list(gd->unsortable_refs, gset))
2320 : : {
2321 : 24 : GroupingSetData *gs = makeNode(GroupingSetData);
2322 : :
2323 : 24 : gs->set = gset;
2324 : 24 : gd->unsortable_sets = lappend(gd->unsortable_sets, gs);
2325 : :
2326 : : /*
2327 : : * We must enforce here that an unsortable set is hashable;
2328 : : * later code assumes this. Parse analysis only checks that
2329 : : * every individual column is either hashable or sortable.
2330 : : *
2331 : : * Note that passing this test doesn't guarantee we can
2332 : : * generate a plan; there might be other showstoppers.
2333 : : */
2334 [ + + ]: 24 : if (bms_overlap_list(gd->unhashable_refs, gset))
2335 [ + - ]: 3 : ereport(ERROR,
2336 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2337 : : errmsg("could not implement GROUP BY"),
2338 : : errdetail("Some of the datatypes only support hashing, while others only support sorting.")));
2339 : : }
2340 : : else
2341 : 21 : sortable_sets = lappend(sortable_sets, gset);
2342 : : }
2343 : :
2344 [ + + ]: 18 : if (sortable_sets)
2345 : 15 : sets = extract_rollup_sets(sortable_sets);
2346 : : else
2347 : 3 : sets = NIL;
2348 : : }
2349 : : else
2350 : 498 : sets = extract_rollup_sets(parse->groupingSets);
2351 : :
2352 [ + + + + : 1348 : foreach(lc_set, sets)
+ + ]
2353 : : {
2354 : 832 : List *current_sets = (List *) lfirst(lc_set);
2355 : 832 : RollupData *rollup = makeNode(RollupData);
2356 : : GroupingSetData *gs;
2357 : :
2358 : : /*
2359 : : * Reorder the current list of grouping sets into correct prefix
2360 : : * order. If only one aggregation pass is needed, try to make the
2361 : : * list match the ORDER BY clause; if more than one pass is needed, we
2362 : : * don't bother with that.
2363 : : *
2364 : : * Note that this reorders the sets from smallest-member-first to
2365 : : * largest-member-first, and applies the GroupingSetData annotations,
2366 : : * though the data will be filled in later.
2367 : : */
2368 [ + + ]: 832 : current_sets = reorder_grouping_sets(current_sets,
2369 : 832 : (list_length(sets) == 1
2370 : : ? parse->sortClause
2371 : : : NIL));
2372 : :
2373 : : /*
2374 : : * Get the initial (and therefore largest) grouping set.
2375 : : */
3113 tgl@sss.pgh.pa.us 2376 : 832 : gs = linitial_node(GroupingSetData, current_sets);
2377 : :
2378 : : /*
2379 : : * Order the groupClause appropriately. If the first grouping set is
2380 : : * empty, then the groupClause must also be empty; otherwise we have
2381 : : * to force the groupClause to match that grouping set's order.
2382 : : *
2383 : : * (The first grouping set can be empty even though parse->groupClause
2384 : : * is not empty only if all non-empty grouping sets are unsortable.
2385 : : * The groupClauses for hashed grouping sets are built later on.)
2386 : : */
3275 rhodiumtoad@postgres 2387 [ + + ]: 832 : if (gs->set)
647 akorotkov@postgresql 2388 : 793 : rollup->groupClause = preprocess_groupclause(root, gs->set);
2389 : : else
3275 rhodiumtoad@postgres 2390 : 39 : rollup->groupClause = NIL;
2391 : :
2392 : : /*
2393 : : * Is it hashable? We pretend empty sets are hashable even though we
2394 : : * actually force them not to be hashed later. But don't bother if
2395 : : * there's nothing but empty sets (since in that case we can't hash
2396 : : * anything).
2397 : : */
2398 [ + + ]: 832 : if (gs->set &&
2399 [ + + ]: 793 : !bms_overlap_list(gd->unhashable_refs, gs->set))
2400 : : {
2401 : 781 : rollup->hashable = true;
2402 : 781 : gd->any_hashable = true;
2403 : : }
2404 : :
2405 : : /*
2406 : : * Now that we've pinned down an order for the groupClause for this
2407 : : * list of grouping sets, we need to remap the entries in the grouping
2408 : : * sets from sortgrouprefs to plain indices (0-based) into the
2409 : : * groupClause for this collection of grouping sets. We keep the
2410 : : * original form for later use, though.
2411 : : */
2412 : 832 : rollup->gsets = remap_to_groupclause_idx(rollup->groupClause,
2413 : : current_sets,
2414 : : gd->tleref_to_colnum_map);
2415 : 832 : rollup->gsets_data = current_sets;
2416 : :
2417 : 832 : gd->rollups = lappend(gd->rollups, rollup);
2418 : : }
2419 : :
2420 [ + + ]: 516 : if (gd->unsortable_sets)
2421 : : {
2422 : : /*
2423 : : * We have not yet pinned down a groupclause for this, but we will
2424 : : * need index-based lists for estimation purposes. Construct
2425 : : * hash_sets_idx based on the entire original groupclause for now.
2426 : : */
2427 : 18 : gd->hash_sets_idx = remap_to_groupclause_idx(parse->groupClause,
2428 : : gd->unsortable_sets,
2429 : : gd->tleref_to_colnum_map);
2430 : 18 : gd->any_hashable = true;
2431 : : }
2432 : :
2433 : 516 : return gd;
2434 : : }
2435 : :
2436 : : /*
2437 : : * Given a groupclause and a list of GroupingSetData, return equivalent sets
2438 : : * (without annotation) mapped to indexes into the given groupclause.
2439 : : */
2440 : : static List *
2441 : 2341 : remap_to_groupclause_idx(List *groupClause,
2442 : : List *gsets,
2443 : : int *tleref_to_colnum_map)
2444 : : {
2445 : 2341 : int ref = 0;
2446 : 2341 : List *result = NIL;
2447 : : ListCell *lc;
2448 : :
2449 [ + + + + : 5632 : foreach(lc, groupClause)
+ + ]
2450 : : {
3113 tgl@sss.pgh.pa.us 2451 : 3291 : SortGroupClause *gc = lfirst_node(SortGroupClause, lc);
2452 : :
3275 rhodiumtoad@postgres 2453 : 3291 : tleref_to_colnum_map[gc->tleSortGroupRef] = ref++;
2454 : : }
2455 : :
2456 [ + - + + : 5380 : foreach(lc, gsets)
+ + ]
2457 : : {
2458 : 3039 : List *set = NIL;
2459 : : ListCell *lc2;
3113 tgl@sss.pgh.pa.us 2460 : 3039 : GroupingSetData *gs = lfirst_node(GroupingSetData, lc);
2461 : :
3275 rhodiumtoad@postgres 2462 [ + + + + : 6761 : foreach(lc2, gs->set)
+ + ]
2463 : : {
2464 : 3722 : set = lappend_int(set, tleref_to_colnum_map[lfirst_int(lc2)]);
2465 : : }
2466 : :
2467 : 3039 : result = lappend(result, set);
2468 : : }
2469 : :
2470 : 2341 : return result;
2471 : : }
2472 : :
2473 : :
2474 : : /*
2475 : : * preprocess_rowmarks - set up PlanRowMarks if needed
2476 : : */
2477 : : static void
5984 tgl@sss.pgh.pa.us 2478 : 287565 : preprocess_rowmarks(PlannerInfo *root)
2479 : : {
2480 : 287565 : Query *parse = root->parse;
2481 : : Bitmapset *rels;
2482 : : List *prowmarks;
2483 : : ListCell *l;
2484 : : int i;
2485 : :
2486 [ + + ]: 287565 : if (parse->rowMarks)
2487 : : {
2488 : : /*
2489 : : * We've got trouble if FOR [KEY] UPDATE/SHARE appears inside
2490 : : * grouping, since grouping renders a reference to individual tuple
2491 : : * CTIDs invalid. This is also checked at parse time, but that's
2492 : : * insufficient because of rule substitution, query pullup, etc.
2493 : : */
3113 2494 : 6819 : CheckSelectLocking(parse, linitial_node(RowMarkClause,
2495 : : parse->rowMarks)->strength);
2496 : : }
2497 : : else
2498 : : {
2499 : : /*
2500 : : * We only need rowmarks for UPDATE, DELETE, MERGE, or FOR [KEY]
2501 : : * UPDATE/SHARE.
2502 : : */
5984 2503 [ + + ]: 280746 : if (parse->commandType != CMD_UPDATE &&
897 dean.a.rasheed@gmail 2504 [ + + ]: 273371 : parse->commandType != CMD_DELETE &&
2505 [ + + ]: 271165 : parse->commandType != CMD_MERGE)
5984 tgl@sss.pgh.pa.us 2506 : 270236 : return;
2507 : : }
2508 : :
2509 : : /*
2510 : : * We need to have rowmarks for all base relations except the target. We
2511 : : * make a bitmapset of all base rels and then remove the items we don't
2512 : : * need or have FOR [KEY] UPDATE/SHARE marks for.
2513 : : */
1140 2514 : 17329 : rels = get_relids_in_jointree((Node *) parse->jointree, false, false);
5984 2515 [ + + ]: 17329 : if (parse->resultRelation)
2516 : 10510 : rels = bms_del_member(rels, parse->resultRelation);
2517 : :
2518 : : /*
2519 : : * Convert RowMarkClauses to PlanRowMark representation.
2520 : : */
2521 : 17329 : prowmarks = NIL;
2522 [ + + + + : 24263 : foreach(l, parse->rowMarks)
+ + ]
2523 : : {
3113 2524 : 6934 : RowMarkClause *rc = lfirst_node(RowMarkClause, l);
5982 2525 : 6934 : RangeTblEntry *rte = rt_fetch(rc->rti, parse->rtable);
2526 : : PlanRowMark *newrc;
2527 : :
2528 : : /*
2529 : : * Currently, it is syntactically impossible to have FOR UPDATE et al
2530 : : * applied to an update/delete target rel. If that ever becomes
2531 : : * possible, we should drop the target from the PlanRowMark list.
2532 : : */
5984 2533 [ - + ]: 6934 : Assert(rc->rti != parse->resultRelation);
2534 : :
2535 : : /*
2536 : : * Ignore RowMarkClauses for subqueries; they aren't real tables and
2537 : : * can't support true locking. Subqueries that got flattened into the
2538 : : * main query should be ignored completely. Any that didn't will get
2539 : : * ROW_MARK_COPY items in the next loop.
2540 : : */
5982 2541 [ + + ]: 6934 : if (rte->rtekind != RTE_RELATION)
2542 : 30 : continue;
2543 : :
5984 2544 : 6904 : rels = bms_del_member(rels, rc->rti);
2545 : :
5982 2546 : 6904 : newrc = makeNode(PlanRowMark);
5984 2547 : 6904 : newrc->rti = newrc->prti = rc->rti;
5513 2548 : 6904 : newrc->rowmarkId = ++(root->glob->lastRowMarkId);
4011 2549 : 6904 : newrc->markType = select_rowmark_type(rte, rc->strength);
4018 2550 : 6904 : newrc->allMarkTypes = (1 << newrc->markType);
2551 : 6904 : newrc->strength = rc->strength;
4177 alvherre@alvh.no-ip. 2552 : 6904 : newrc->waitPolicy = rc->waitPolicy;
5984 tgl@sss.pgh.pa.us 2553 : 6904 : newrc->isParent = false;
2554 : :
2555 : 6904 : prowmarks = lappend(prowmarks, newrc);
2556 : : }
2557 : :
2558 : : /*
2559 : : * Now, add rowmarks for any non-target, non-locked base relations.
2560 : : */
2561 : 17329 : i = 0;
2562 [ + - + + : 40094 : foreach(l, parse->rtable)
+ + ]
2563 : : {
3113 2564 : 22765 : RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
2565 : : PlanRowMark *newrc;
2566 : :
5984 2567 : 22765 : i++;
2568 [ + + ]: 22765 : if (!bms_is_member(i, rels))
2569 : 20878 : continue;
2570 : :
2571 : 1887 : newrc = makeNode(PlanRowMark);
2572 : 1887 : newrc->rti = newrc->prti = i;
5513 2573 : 1887 : newrc->rowmarkId = ++(root->glob->lastRowMarkId);
4011 2574 : 1887 : newrc->markType = select_rowmark_type(rte, LCS_NONE);
4018 2575 : 1887 : newrc->allMarkTypes = (1 << newrc->markType);
2576 : 1887 : newrc->strength = LCS_NONE;
3189 2577 : 1887 : newrc->waitPolicy = LockWaitBlock; /* doesn't matter */
5984 2578 : 1887 : newrc->isParent = false;
2579 : :
2580 : 1887 : prowmarks = lappend(prowmarks, newrc);
2581 : : }
2582 : :
2583 : 17329 : root->rowMarks = prowmarks;
2584 : : }
2585 : :
2586 : : /*
2587 : : * Select RowMarkType to use for a given table
2588 : : */
2589 : : RowMarkType
4011 2590 : 9999 : select_rowmark_type(RangeTblEntry *rte, LockClauseStrength strength)
2591 : : {
2592 [ + + ]: 9999 : if (rte->rtekind != RTE_RELATION)
2593 : : {
2594 : : /* If it's not a table at all, use ROW_MARK_COPY */
2595 : 721 : return ROW_MARK_COPY;
2596 : : }
2597 [ + + ]: 9278 : else if (rte->relkind == RELKIND_FOREIGN_TABLE)
2598 : : {
2599 : : /* Let the FDW select the rowmark type, if it wants to */
3960 2600 : 114 : FdwRoutine *fdwroutine = GetFdwRoutineByRelId(rte->relid);
2601 : :
2602 [ - + ]: 114 : if (fdwroutine->GetForeignRowMarkType != NULL)
3960 tgl@sss.pgh.pa.us 2603 :UBC 0 : return fdwroutine->GetForeignRowMarkType(rte, strength);
2604 : : /* Otherwise, use ROW_MARK_COPY by default */
4011 tgl@sss.pgh.pa.us 2605 :CBC 114 : return ROW_MARK_COPY;
2606 : : }
2607 : : else
2608 : : {
2609 : : /* Regular table, apply the appropriate lock type */
2610 [ + + + + : 9164 : switch (strength)
+ - ]
2611 : : {
2612 : 1273 : case LCS_NONE:
2613 : :
2614 : : /*
2615 : : * We don't need a tuple lock, only the ability to re-fetch
2616 : : * the row.
2617 : : */
2618 : 1273 : return ROW_MARK_REFERENCE;
2619 : : break;
2620 : 6917 : case LCS_FORKEYSHARE:
2621 : 6917 : return ROW_MARK_KEYSHARE;
2622 : : break;
2623 : 157 : case LCS_FORSHARE:
2624 : 157 : return ROW_MARK_SHARE;
2625 : : break;
2626 : 39 : case LCS_FORNOKEYUPDATE:
2627 : 39 : return ROW_MARK_NOKEYEXCLUSIVE;
2628 : : break;
2629 : 778 : case LCS_FORUPDATE:
2630 : 778 : return ROW_MARK_EXCLUSIVE;
2631 : : break;
2632 : : }
4011 tgl@sss.pgh.pa.us 2633 [ # # ]:UBC 0 : elog(ERROR, "unrecognized LockClauseStrength %d", (int) strength);
2634 : : return ROW_MARK_EXCLUSIVE; /* keep compiler quiet */
2635 : : }
2636 : : }
2637 : :
2638 : : /*
2639 : : * preprocess_limit - do pre-estimation for LIMIT and/or OFFSET clauses
2640 : : *
2641 : : * We try to estimate the values of the LIMIT/OFFSET clauses, and pass the
2642 : : * results back in *count_est and *offset_est. These variables are set to
2643 : : * 0 if the corresponding clause is not present, and -1 if it's present
2644 : : * but we couldn't estimate the value for it. (The "0" convention is OK
2645 : : * for OFFSET but a little bit bogus for LIMIT: effectively we estimate
2646 : : * LIMIT 0 as though it were LIMIT 1. But this is in line with the planner's
2647 : : * usual practice of never estimating less than one row.) These values will
2648 : : * be passed to create_limit_path, which see if you change this code.
2649 : : *
2650 : : * The return value is the suitably adjusted tuple_fraction to use for
2651 : : * planning the query. This adjustment is not overridable, since it reflects
2652 : : * plan actions that grouping_planner() will certainly take, not assumptions
2653 : : * about context.
2654 : : */
2655 : : static double
7514 tgl@sss.pgh.pa.us 2656 :CBC 2623 : preprocess_limit(PlannerInfo *root, double tuple_fraction,
2657 : : int64 *offset_est, int64 *count_est)
2658 : : {
7583 2659 : 2623 : Query *parse = root->parse;
2660 : : Node *est;
2661 : : double limit_fraction;
2662 : :
2663 : : /* Should not be called unless LIMIT or OFFSET */
7514 2664 [ + + - + ]: 2623 : Assert(parse->limitCount || parse->limitOffset);
2665 : :
2666 : : /*
2667 : : * Try to obtain the clause values. We use estimate_expression_value
2668 : : * primarily because it can sometimes do something useful with Params.
2669 : : */
2670 [ + + ]: 2623 : if (parse->limitCount)
2671 : : {
6964 2672 : 2349 : est = estimate_expression_value(root, parse->limitCount);
7514 2673 [ + - + + ]: 2349 : if (est && IsA(est, Const))
2674 : : {
2675 [ - + ]: 2346 : if (((Const *) est)->constisnull)
2676 : : {
2677 : : /* NULL indicates LIMIT ALL, ie, no limit */
7456 bruce@momjian.us 2678 :UBC 0 : *count_est = 0; /* treat as not present */
2679 : : }
2680 : : else
2681 : : {
7172 bruce@momjian.us 2682 :CBC 2346 : *count_est = DatumGetInt64(((Const *) est)->constvalue);
7514 tgl@sss.pgh.pa.us 2683 [ + + ]: 2346 : if (*count_est <= 0)
3189 2684 : 75 : *count_est = 1; /* force to at least 1 */
2685 : : }
2686 : : }
2687 : : else
7514 2688 : 3 : *count_est = -1; /* can't estimate */
2689 : : }
2690 : : else
2691 : 274 : *count_est = 0; /* not present */
2692 : :
2693 [ + + ]: 2623 : if (parse->limitOffset)
2694 : : {
6964 2695 : 460 : est = estimate_expression_value(root, parse->limitOffset);
7514 2696 [ + - + + ]: 460 : if (est && IsA(est, Const))
2697 : : {
2698 [ - + ]: 448 : if (((Const *) est)->constisnull)
2699 : : {
2700 : : /* Treat NULL as no offset; the executor will too */
7456 bruce@momjian.us 2701 :UBC 0 : *offset_est = 0; /* treat as not present */
2702 : : }
2703 : : else
2704 : : {
7172 bruce@momjian.us 2705 :CBC 448 : *offset_est = DatumGetInt64(((Const *) est)->constvalue);
7514 tgl@sss.pgh.pa.us 2706 [ - + ]: 448 : if (*offset_est < 0)
4254 tgl@sss.pgh.pa.us 2707 :UBC 0 : *offset_est = 0; /* treat as not present */
2708 : : }
2709 : : }
2710 : : else
7514 tgl@sss.pgh.pa.us 2711 :CBC 12 : *offset_est = -1; /* can't estimate */
2712 : : }
2713 : : else
2714 : 2163 : *offset_est = 0; /* not present */
2715 : :
2716 [ + + ]: 2623 : if (*count_est != 0)
2717 : : {
2718 : : /*
2719 : : * A LIMIT clause limits the absolute number of tuples returned.
2720 : : * However, if it's not a constant LIMIT then we have to guess; for
2721 : : * lack of a better idea, assume 10% of the plan's result is wanted.
2722 : : */
2723 [ + + + + ]: 2349 : if (*count_est < 0 || *offset_est < 0)
2724 : : {
2725 : : /* LIMIT or OFFSET is an expression ... punt ... */
2726 : 12 : limit_fraction = 0.10;
2727 : : }
2728 : : else
2729 : : {
2730 : : /* LIMIT (plus OFFSET, if any) is max number of tuples needed */
2731 : 2337 : limit_fraction = (double) *count_est + (double) *offset_est;
2732 : : }
2733 : :
2734 : : /*
2735 : : * If we have absolute limits from both caller and LIMIT, use the
2736 : : * smaller value; likewise if they are both fractional. If one is
2737 : : * fractional and the other absolute, we can't easily determine which
2738 : : * is smaller, but we use the heuristic that the absolute will usually
2739 : : * be smaller.
2740 : : */
7583 2741 [ + + ]: 2349 : if (tuple_fraction >= 1.0)
2742 : : {
2743 [ + - ]: 3 : if (limit_fraction >= 1.0)
2744 : : {
2745 : : /* both absolute */
2746 [ - + ]: 3 : tuple_fraction = Min(tuple_fraction, limit_fraction);
2747 : : }
2748 : : else
2749 : : {
2750 : : /* caller absolute, limit fractional; use caller's value */
2751 : : }
2752 : : }
2753 [ + + ]: 2346 : else if (tuple_fraction > 0.0)
2754 : : {
2755 [ + - ]: 74 : if (limit_fraction >= 1.0)
2756 : : {
2757 : : /* caller fractional, limit absolute; use limit */
7514 2758 : 74 : tuple_fraction = limit_fraction;
2759 : : }
2760 : : else
2761 : : {
2762 : : /* both fractional */
7514 tgl@sss.pgh.pa.us 2763 [ # # ]:UBC 0 : tuple_fraction = Min(tuple_fraction, limit_fraction);
2764 : : }
2765 : : }
2766 : : else
2767 : : {
2768 : : /* no info from caller, just use limit */
7583 tgl@sss.pgh.pa.us 2769 :CBC 2272 : tuple_fraction = limit_fraction;
2770 : : }
2771 : : }
7514 2772 [ + + + + ]: 274 : else if (*offset_est != 0 && tuple_fraction > 0.0)
2773 : : {
2774 : : /*
2775 : : * We have an OFFSET but no LIMIT. This acts entirely differently
2776 : : * from the LIMIT case: here, we need to increase rather than decrease
2777 : : * the caller's tuple_fraction, because the OFFSET acts to cause more
2778 : : * tuples to be fetched instead of fewer. This only matters if we got
2779 : : * a tuple_fraction > 0, however.
2780 : : *
2781 : : * As above, use 10% if OFFSET is present but unestimatable.
2782 : : */
2783 [ - + ]: 8 : if (*offset_est < 0)
7514 tgl@sss.pgh.pa.us 2784 :UBC 0 : limit_fraction = 0.10;
2785 : : else
7514 tgl@sss.pgh.pa.us 2786 :CBC 8 : limit_fraction = (double) *offset_est;
2787 : :
2788 : : /*
2789 : : * If we have absolute counts from both caller and OFFSET, add them
2790 : : * together; likewise if they are both fractional. If one is
2791 : : * fractional and the other absolute, we want to take the larger, and
2792 : : * we heuristically assume that's the fractional one.
2793 : : */
2794 [ - + ]: 8 : if (tuple_fraction >= 1.0)
2795 : : {
7514 tgl@sss.pgh.pa.us 2796 [ # # ]:UBC 0 : if (limit_fraction >= 1.0)
2797 : : {
2798 : : /* both absolute, so add them together */
2799 : 0 : tuple_fraction += limit_fraction;
2800 : : }
2801 : : else
2802 : : {
2803 : : /* caller absolute, limit fractional; use limit */
2804 : 0 : tuple_fraction = limit_fraction;
2805 : : }
2806 : : }
2807 : : else
2808 : : {
7514 tgl@sss.pgh.pa.us 2809 [ - + ]:CBC 8 : if (limit_fraction >= 1.0)
2810 : : {
2811 : : /* caller fractional, limit absolute; use caller's value */
2812 : : }
2813 : : else
2814 : : {
2815 : : /* both fractional, so add them together */
7514 tgl@sss.pgh.pa.us 2816 :UBC 0 : tuple_fraction += limit_fraction;
2817 [ # # ]: 0 : if (tuple_fraction >= 1.0)
3189 2818 : 0 : tuple_fraction = 0.0; /* assume fetch all */
2819 : : }
2820 : : }
2821 : : }
2822 : :
7583 tgl@sss.pgh.pa.us 2823 :CBC 2623 : return tuple_fraction;
2824 : : }
2825 : :
2826 : : /*
2827 : : * limit_needed - do we actually need a Limit plan node?
2828 : : *
2829 : : * If we have constant-zero OFFSET and constant-null LIMIT, we can skip adding
2830 : : * a Limit node. This is worth checking for because "OFFSET 0" is a common
2831 : : * locution for an optimization fence. (Because other places in the planner
2832 : : * merely check whether parse->limitOffset isn't NULL, it will still work as
2833 : : * an optimization fence --- we're just suppressing unnecessary run-time
2834 : : * overhead.)
2835 : : *
2836 : : * This might look like it could be merged into preprocess_limit, but there's
2837 : : * a key distinction: here we need hard constants in OFFSET/LIMIT, whereas
2838 : : * in preprocess_limit it's good enough to consider estimated values.
2839 : : */
2840 : : bool
4749 2841 : 611017 : limit_needed(Query *parse)
2842 : : {
2843 : : Node *node;
2844 : :
2845 : 611017 : node = parse->limitCount;
2846 [ + + ]: 611017 : if (node)
2847 : : {
2848 [ + + ]: 5619 : if (IsA(node, Const))
2849 : : {
2850 : : /* NULL indicates LIMIT ALL, ie, no limit */
2851 [ + - ]: 5501 : if (!((Const *) node)->constisnull)
2852 : 5501 : return true; /* LIMIT with a constant value */
2853 : : }
2854 : : else
2855 : 118 : return true; /* non-constant LIMIT */
2856 : : }
2857 : :
2858 : 605398 : node = parse->limitOffset;
2859 [ + + ]: 605398 : if (node)
2860 : : {
2861 [ + + ]: 791 : if (IsA(node, Const))
2862 : : {
2863 : : /* Treat NULL as no offset; the executor would too */
2864 [ + - ]: 635 : if (!((Const *) node)->constisnull)
2865 : : {
4673 bruce@momjian.us 2866 : 635 : int64 offset = DatumGetInt64(((Const *) node)->constvalue);
2867 : :
4254 tgl@sss.pgh.pa.us 2868 [ + + ]: 635 : if (offset != 0)
2869 : 73 : return true; /* OFFSET with a nonzero value */
2870 : : }
2871 : : }
2872 : : else
4749 2873 : 156 : return true; /* non-constant OFFSET */
2874 : : }
2875 : :
2876 : 605169 : return false; /* don't need a Limit plan node */
2877 : : }
2878 : :
2879 : : /*
2880 : : * preprocess_groupclause - do preparatory work on GROUP BY clause
2881 : : *
2882 : : * The idea here is to adjust the ordering of the GROUP BY elements
2883 : : * (which in itself is semantically insignificant) to match ORDER BY,
2884 : : * thereby allowing a single sort operation to both implement the ORDER BY
2885 : : * requirement and set up for a Unique step that implements GROUP BY.
2886 : : * We also consider partial match between GROUP BY and ORDER BY elements,
2887 : : * which could allow to implement ORDER BY using the incremental sort.
2888 : : *
2889 : : * We also consider other orderings of the GROUP BY elements, which could
2890 : : * match the sort ordering of other possible plans (eg an indexscan) and
2891 : : * thereby reduce cost. This is implemented during the generation of grouping
2892 : : * paths. See get_useful_group_keys_orderings() for details.
2893 : : *
2894 : : * Note: we need no comparable processing of the distinctClause because
2895 : : * the parser already enforced that that matches ORDER BY.
2896 : : *
2897 : : * Note: we return a fresh List, but its elements are the same
2898 : : * SortGroupClauses appearing in parse->groupClause. This is important
2899 : : * because later processing may modify the processed_groupClause list.
2900 : : *
2901 : : * For grouping sets, the order of items is instead forced to agree with that
2902 : : * of the grouping set (and items not in the grouping set are skipped). The
2903 : : * work of sorting the order of grouping set elements to match the ORDER BY if
2904 : : * possible is done elsewhere.
2905 : : */
2906 : : static List *
647 akorotkov@postgresql 2907 : 4361 : preprocess_groupclause(PlannerInfo *root, List *force)
2908 : : {
6434 tgl@sss.pgh.pa.us 2909 : 4361 : Query *parse = root->parse;
3956 andres@anarazel.de 2910 : 4361 : List *new_groupclause = NIL;
2911 : : ListCell *sl;
2912 : : ListCell *gl;
2913 : :
2914 : : /* For grouping sets, we need to force the ordering */
647 akorotkov@postgresql 2915 [ + + ]: 4361 : if (force)
2916 : : {
2917 [ + - + + : 5536 : foreach(sl, force)
+ + ]
2918 : : {
2919 : 3252 : Index ref = lfirst_int(sl);
2920 : 3252 : SortGroupClause *cl = get_sortgroupref_clause(ref, parse->groupClause);
2921 : :
2922 : 3252 : new_groupclause = lappend(new_groupclause, cl);
2923 : : }
2924 : :
2925 : 2284 : return new_groupclause;
2926 : : }
2927 : :
2928 : : /* If no ORDER BY, nothing useful to do here */
2929 [ + + ]: 2077 : if (parse->sortClause == NIL)
2930 : 1164 : return list_copy(parse->groupClause);
2931 : :
2932 : : /*
2933 : : * Scan the ORDER BY clause and construct a list of matching GROUP BY
2934 : : * items, but only as far as we can make a matching prefix.
2935 : : *
2936 : : * This code assumes that the sortClause contains no duplicate items.
2937 : : */
2938 [ + - + + : 1779 : foreach(sl, parse->sortClause)
+ + ]
2939 : : {
2940 : 1189 : SortGroupClause *sc = lfirst_node(SortGroupClause, sl);
2941 : :
2942 [ + - + + : 1737 : foreach(gl, parse->groupClause)
+ + ]
2943 : : {
2944 : 1414 : SortGroupClause *gc = lfirst_node(SortGroupClause, gl);
2945 : :
2946 [ + + ]: 1414 : if (equal(gc, sc))
2947 : : {
2948 : 866 : new_groupclause = lappend(new_groupclause, gc);
2949 : 866 : break;
2950 : : }
2951 : : }
2952 [ + + ]: 1189 : if (gl == NULL)
2953 : 323 : break; /* no match, so stop scanning */
2954 : : }
2955 : :
2956 : :
2957 : : /* If no match at all, no point in reordering GROUP BY */
2958 [ + + ]: 913 : if (new_groupclause == NIL)
2959 : 149 : return list_copy(parse->groupClause);
2960 : :
2961 : : /*
2962 : : * Add any remaining GROUP BY items to the new list. We don't require a
2963 : : * complete match, because even partial match allows ORDER BY to be
2964 : : * implemented using incremental sort. Also, give up if there are any
2965 : : * non-sortable GROUP BY items, since then there's no hope anyway.
2966 : : */
2967 [ + - + + : 1713 : foreach(gl, parse->groupClause)
+ + ]
2968 : : {
2969 : 949 : SortGroupClause *gc = lfirst_node(SortGroupClause, gl);
2970 : :
2971 [ + + ]: 949 : if (list_member_ptr(new_groupclause, gc))
2972 : 866 : continue; /* it matched an ORDER BY item */
2973 [ - + ]: 83 : if (!OidIsValid(gc->sortop)) /* give up, GROUP BY can't be sorted */
647 akorotkov@postgresql 2974 :UBC 0 : return list_copy(parse->groupClause);
647 akorotkov@postgresql 2975 :CBC 83 : new_groupclause = lappend(new_groupclause, gc);
2976 : : }
2977 : :
2978 : : /* Success --- install the rearranged GROUP BY list */
2979 [ - + ]: 764 : Assert(list_length(parse->groupClause) == list_length(new_groupclause));
3956 andres@anarazel.de 2980 : 764 : return new_groupclause;
2981 : : }
2982 : :
2983 : : /*
2984 : : * Extract lists of grouping sets that can be implemented using a single
2985 : : * rollup-type aggregate pass each. Returns a list of lists of grouping sets.
2986 : : *
2987 : : * Input must be sorted with smallest sets first. Result has each sublist
2988 : : * sorted with smallest sets first.
2989 : : *
2990 : : * We want to produce the absolute minimum possible number of lists here to
2991 : : * avoid excess sorts. Fortunately, there is an algorithm for this; the problem
2992 : : * of finding the minimal partition of a partially-ordered set into chains
2993 : : * (which is what we need, taking the list of grouping sets as a poset ordered
2994 : : * by set inclusion) can be mapped to the problem of finding the maximum
2995 : : * cardinality matching on a bipartite graph, which is solvable in polynomial
2996 : : * time with a worst case of no worse than O(n^2.5) and usually much
2997 : : * better. Since our N is at most 4096, we don't need to consider fallbacks to
2998 : : * heuristic or approximate methods. (Planning time for a 12-d cube is under
2999 : : * half a second on my modest system even with optimization off and assertions
3000 : : * on.)
3001 : : */
3002 : : static List *
3003 : 513 : extract_rollup_sets(List *groupingSets)
3004 : : {
3005 : 513 : int num_sets_raw = list_length(groupingSets);
3006 : 513 : int num_empty = 0;
3949 bruce@momjian.us 3007 : 513 : int num_sets = 0; /* distinct sets */
3956 andres@anarazel.de 3008 : 513 : int num_chains = 0;
3009 : 513 : List *result = NIL;
3010 : : List **results;
3011 : : List **orig_sets;
3012 : : Bitmapset **set_masks;
3013 : : int *chains;
3014 : : short **adjacency;
3015 : : short *adjacency_buf;
3016 : : BipartiteMatchState *state;
3017 : : int i;
3018 : : int j;
3019 : : int j_size;
3020 : 513 : ListCell *lc1 = list_head(groupingSets);
3021 : : ListCell *lc;
3022 : :
3023 : : /*
3024 : : * Start by stripping out empty sets. The algorithm doesn't require this,
3025 : : * but the planner currently needs all empty sets to be returned in the
3026 : : * first list, so we strip them here and add them back after.
3027 : : */
3028 [ + + + + ]: 871 : while (lc1 && lfirst(lc1) == NIL)
3029 : : {
3030 : 358 : ++num_empty;
2435 tgl@sss.pgh.pa.us 3031 : 358 : lc1 = lnext(groupingSets, lc1);
3032 : : }
3033 : :
3034 : : /* bail out now if it turns out that all we had were empty sets. */
3956 andres@anarazel.de 3035 [ + + ]: 513 : if (!lc1)
3036 : 39 : return list_make1(groupingSets);
3037 : :
3038 : : /*----------
3039 : : * We don't strictly need to remove duplicate sets here, but if we don't,
3040 : : * they tend to become scattered through the result, which is a bit
3041 : : * confusing (and irritating if we ever decide to optimize them out).
3042 : : * So we remove them here and add them back after.
3043 : : *
3044 : : * For each non-duplicate set, we fill in the following:
3045 : : *
3046 : : * orig_sets[i] = list of the original set lists
3047 : : * set_masks[i] = bitmapset for testing inclusion
3048 : : * adjacency[i] = array [n, v1, v2, ... vn] of adjacency indices
3049 : : *
3050 : : * chains[i] will be the result group this set is assigned to.
3051 : : *
3052 : : * We index all of these from 1 rather than 0 because it is convenient
3053 : : * to leave 0 free for the NIL node in the graph algorithm.
3054 : : *----------
3055 : : */
3949 bruce@momjian.us 3056 : 474 : orig_sets = palloc0((num_sets_raw + 1) * sizeof(List *));
3956 andres@anarazel.de 3057 : 474 : set_masks = palloc0((num_sets_raw + 1) * sizeof(Bitmapset *));
3058 : 474 : adjacency = palloc0((num_sets_raw + 1) * sizeof(short *));
3059 : 474 : adjacency_buf = palloc((num_sets_raw + 1) * sizeof(short));
3060 : :
3061 : 474 : j_size = 0;
3062 : 474 : j = 0;
3063 : 474 : i = 1;
3064 : :
2435 tgl@sss.pgh.pa.us 3065 [ + - + + : 1643 : for_each_cell(lc, groupingSets, lc1)
+ + ]
3066 : : {
3113 3067 : 1169 : List *candidate = (List *) lfirst(lc);
3956 andres@anarazel.de 3068 : 1169 : Bitmapset *candidate_set = NULL;
3069 : : ListCell *lc2;
3070 : 1169 : int dup_of = 0;
3071 : :
3072 [ + - + + : 2803 : foreach(lc2, candidate)
+ + ]
3073 : : {
3074 : 1634 : candidate_set = bms_add_member(candidate_set, lfirst_int(lc2));
3075 : : }
3076 : :
3077 : : /* we can only be a dup if we're the same length as a previous set */
3078 [ + + ]: 1169 : if (j_size == list_length(candidate))
3079 : : {
3080 : : int k;
3081 : :
3082 [ + + ]: 1042 : for (k = j; k < i; ++k)
3083 : : {
3084 [ + + ]: 675 : if (bms_equal(set_masks[k], candidate_set))
3085 : : {
3086 : 79 : dup_of = k;
3087 : 79 : break;
3088 : : }
3089 : : }
3090 : : }
3091 [ + - ]: 723 : else if (j_size < list_length(candidate))
3092 : : {
3093 : 723 : j_size = list_length(candidate);
3094 : 723 : j = i;
3095 : : }
3096 : :
3097 [ + + ]: 1169 : if (dup_of > 0)
3098 : : {
3099 : 79 : orig_sets[dup_of] = lappend(orig_sets[dup_of], candidate);
3100 : 79 : bms_free(candidate_set);
3101 : : }
3102 : : else
3103 : : {
3104 : : int k;
3949 bruce@momjian.us 3105 : 1090 : int n_adj = 0;
3106 : :
3956 andres@anarazel.de 3107 : 1090 : orig_sets[i] = list_make1(candidate);
3108 : 1090 : set_masks[i] = candidate_set;
3109 : :
3110 : : /* fill in adjacency list; no need to compare equal-size sets */
3111 : :
3112 [ + + ]: 1738 : for (k = j - 1; k > 0; --k)
3113 : : {
3114 [ + + ]: 648 : if (bms_is_subset(set_masks[k], candidate_set))
3115 : 567 : adjacency_buf[++n_adj] = k;
3116 : : }
3117 : :
3118 [ + + ]: 1090 : if (n_adj > 0)
3119 : : {
3120 : 311 : adjacency_buf[0] = n_adj;
3121 : 311 : adjacency[i] = palloc((n_adj + 1) * sizeof(short));
3122 : 311 : memcpy(adjacency[i], adjacency_buf, (n_adj + 1) * sizeof(short));
3123 : : }
3124 : : else
3125 : 779 : adjacency[i] = NULL;
3126 : :
3127 : 1090 : ++i;
3128 : : }
3129 : : }
3130 : :
3131 : 474 : num_sets = i - 1;
3132 : :
3133 : : /*
3134 : : * Apply the graph matching algorithm to do the work.
3135 : : */
3136 : 474 : state = BipartiteMatch(num_sets, num_sets, adjacency);
3137 : :
3138 : : /*
3139 : : * Now, the state->pair* fields have the info we need to assign sets to
3140 : : * chains. Two sets (u,v) belong to the same chain if pair_uv[u] = v or
3141 : : * pair_vu[v] = u (both will be true, but we check both so that we can do
3142 : : * it in one pass)
3143 : : */
3144 : 474 : chains = palloc0((num_sets + 1) * sizeof(int));
3145 : :
3146 [ + + ]: 1564 : for (i = 1; i <= num_sets; ++i)
3147 : : {
3949 bruce@momjian.us 3148 : 1090 : int u = state->pair_vu[i];
3149 : 1090 : int v = state->pair_uv[i];
3150 : :
3956 andres@anarazel.de 3151 [ + + - + ]: 1090 : if (u > 0 && u < i)
3956 andres@anarazel.de 3152 :UBC 0 : chains[i] = chains[u];
3956 andres@anarazel.de 3153 [ + + + - ]:CBC 1090 : else if (v > 0 && v < i)
3154 : 297 : chains[i] = chains[v];
3155 : : else
3156 : 793 : chains[i] = ++num_chains;
3157 : : }
3158 : :
3159 : : /* build result lists. */
3949 bruce@momjian.us 3160 : 474 : results = palloc0((num_chains + 1) * sizeof(List *));
3161 : :
3956 andres@anarazel.de 3162 [ + + ]: 1564 : for (i = 1; i <= num_sets; ++i)
3163 : : {
3949 bruce@momjian.us 3164 : 1090 : int c = chains[i];
3165 : :
3956 andres@anarazel.de 3166 [ - + ]: 1090 : Assert(c > 0);
3167 : :
3168 : 1090 : results[c] = list_concat(results[c], orig_sets[i]);
3169 : : }
3170 : :
3171 : : /* push any empty sets back on the first list. */
3172 [ + + ]: 763 : while (num_empty-- > 0)
3173 : 289 : results[1] = lcons(NIL, results[1]);
3174 : :
3175 : : /* make result list */
3176 [ + + ]: 1267 : for (i = 1; i <= num_chains; ++i)
3177 : 793 : result = lappend(result, results[i]);
3178 : :
3179 : : /*
3180 : : * Free all the things.
3181 : : *
3182 : : * (This is over-fussy for small sets but for large sets we could have
3183 : : * tied up a nontrivial amount of memory.)
3184 : : */
3185 : 474 : BipartiteMatchFree(state);
3186 : 474 : pfree(results);
3187 : 474 : pfree(chains);
3188 [ + + ]: 1564 : for (i = 1; i <= num_sets; ++i)
3189 [ + + ]: 1090 : if (adjacency[i])
3190 : 311 : pfree(adjacency[i]);
3191 : 474 : pfree(adjacency);
3192 : 474 : pfree(adjacency_buf);
3193 : 474 : pfree(orig_sets);
3194 [ + + ]: 1564 : for (i = 1; i <= num_sets; ++i)
3195 : 1090 : bms_free(set_masks[i]);
3196 : 474 : pfree(set_masks);
3197 : :
3198 : 474 : return result;
3199 : : }
3200 : :
3201 : : /*
3202 : : * Reorder the elements of a list of grouping sets such that they have correct
3203 : : * prefix relationships. Also inserts the GroupingSetData annotations.
3204 : : *
3205 : : * The input must be ordered with smallest sets first; the result is returned
3206 : : * with largest sets first. Note that the result shares no list substructure
3207 : : * with the input, so it's safe for the caller to modify it later.
3208 : : *
3209 : : * If we're passed in a sortclause, we follow its order of columns to the
3210 : : * extent possible, to minimize the chance that we add unnecessary sorts.
3211 : : * (We're trying here to ensure that GROUPING SETS ((a,b,c),(c)) ORDER BY c,b,a
3212 : : * gets implemented in one pass.)
3213 : : */
3214 : : static List *
1272 pg@bowt.ie 3215 : 832 : reorder_grouping_sets(List *groupingSets, List *sortclause)
3216 : : {
3217 : : ListCell *lc;
3956 andres@anarazel.de 3218 : 832 : List *previous = NIL;
3219 : 832 : List *result = NIL;
3220 : :
1272 pg@bowt.ie 3221 [ + - + + : 2359 : foreach(lc, groupingSets)
+ + ]
3222 : : {
3113 tgl@sss.pgh.pa.us 3223 : 1527 : List *candidate = (List *) lfirst(lc);
3949 bruce@momjian.us 3224 : 1527 : List *new_elems = list_difference_int(candidate, previous);
3275 rhodiumtoad@postgres 3225 : 1527 : GroupingSetData *gs = makeNode(GroupingSetData);
3226 : :
2450 3227 [ + + + + ]: 1615 : while (list_length(sortclause) > list_length(previous) &&
3228 : : new_elems != NIL)
3229 : : {
3230 : 148 : SortGroupClause *sc = list_nth(sortclause, list_length(previous));
3231 : 148 : int ref = sc->tleSortGroupRef;
3232 : :
3233 [ + + ]: 148 : if (list_member_int(new_elems, ref))
3234 : : {
3235 : 88 : previous = lappend_int(previous, ref);
3236 : 88 : new_elems = list_delete_int(new_elems, ref);
3237 : : }
3238 : : else
3239 : : {
3240 : : /* diverged from the sortclause; give up on it */
3241 : 60 : sortclause = NIL;
3242 : 60 : break;
3243 : : }
3244 : : }
3245 : :
3246 : 1527 : previous = list_concat(previous, new_elems);
3247 : :
3275 3248 : 1527 : gs->set = list_copy(previous);
3249 : 1527 : result = lcons(gs, result);
3250 : : }
3251 : :
3956 andres@anarazel.de 3252 : 832 : list_free(previous);
3253 : :
3254 : 832 : return result;
3255 : : }
3256 : :
3257 : : /*
3258 : : * has_volatile_pathkey
3259 : : * Returns true if any PathKey in 'keys' has an EquivalenceClass
3260 : : * containing a volatile function. Otherwise returns false.
3261 : : */
3262 : : static bool
1153 drowley@postgresql.o 3263 : 1641 : has_volatile_pathkey(List *keys)
3264 : : {
3265 : : ListCell *lc;
3266 : :
3267 [ + + + + : 3354 : foreach(lc, keys)
+ + ]
3268 : : {
3269 : 1722 : PathKey *pathkey = lfirst_node(PathKey, lc);
3270 : :
3271 [ + + ]: 1722 : if (pathkey->pk_eclass->ec_has_volatile)
3272 : 9 : return true;
3273 : : }
3274 : :
3275 : 1632 : return false;
3276 : : }
3277 : :
3278 : : /*
3279 : : * adjust_group_pathkeys_for_groupagg
3280 : : * Add pathkeys to root->group_pathkeys to reflect the best set of
3281 : : * pre-ordered input for ordered aggregates.
3282 : : *
3283 : : * We define "best" as the pathkeys that suit the largest number of
3284 : : * aggregate functions. We find these by looking at the first ORDER BY /
3285 : : * DISTINCT aggregate and take the pathkeys for that before searching for
3286 : : * other aggregates that require the same or a more strict variation of the
3287 : : * same pathkeys. We then repeat that process for any remaining aggregates
3288 : : * with different pathkeys and if we find another set of pathkeys that suits a
3289 : : * larger number of aggregates then we select those pathkeys instead.
3290 : : *
3291 : : * When the best pathkeys are found we also mark each Aggref that can use
3292 : : * those pathkeys as aggpresorted = true.
3293 : : *
3294 : : * Note: When an aggregate function's ORDER BY / DISTINCT clause contains any
3295 : : * volatile functions, we never make use of these pathkeys. We want to ensure
3296 : : * that sorts using volatile functions are done independently in each Aggref
3297 : : * rather than once at the query level. If we were to allow this then Aggrefs
3298 : : * with compatible sort orders would all transition their rows in the same
3299 : : * order if those pathkeys were deemed to be the best pathkeys to sort on.
3300 : : * Whereas, if some other set of Aggref's pathkeys happened to be deemed
3301 : : * better pathkeys to sort on, then the volatile function Aggrefs would be
3302 : : * left to perform their sorts individually. To avoid this inconsistent
3303 : : * behavior which could make Aggref results depend on what other Aggrefs the
3304 : : * query contains, we always force Aggrefs with volatile functions to perform
3305 : : * their own sorts.
3306 : : */
3307 : : static void
1152 tgl@sss.pgh.pa.us 3308 : 1443 : adjust_group_pathkeys_for_groupagg(PlannerInfo *root)
3309 : : {
3310 : 1443 : List *grouppathkeys = root->group_pathkeys;
3311 : : List *bestpathkeys;
3312 : : Bitmapset *bestaggs;
3313 : : Bitmapset *unprocessed_aggs;
3314 : : ListCell *lc;
3315 : : int i;
3316 : :
3317 : : /* Shouldn't be here if there are grouping sets */
3318 [ - + ]: 1443 : Assert(root->parse->groupingSets == NIL);
3319 : : /* Shouldn't be here unless there are some ordered aggregates */
3320 [ - + ]: 1443 : Assert(root->numOrderedAggs > 0);
3321 : :
3322 : : /* Do nothing if disabled */
3323 [ + + ]: 1443 : if (!enable_presorted_aggregate)
3324 : 3 : return;
3325 : :
3326 : : /*
3327 : : * Make a first pass over all AggInfos to collect a Bitmapset containing
3328 : : * the indexes of all AggInfos to be processed below.
3329 : : */
1321 drowley@postgresql.o 3330 : 1440 : unprocessed_aggs = NULL;
3331 [ + - + + : 3222 : foreach(lc, root->agginfos)
+ + ]
3332 : : {
3333 : 1782 : AggInfo *agginfo = lfirst_node(AggInfo, lc);
3334 : 1782 : Aggref *aggref = linitial_node(Aggref, agginfo->aggrefs);
3335 : :
3336 [ + + ]: 1782 : if (AGGKIND_IS_ORDERED_SET(aggref->aggkind))
3337 : 132 : continue;
3338 : :
3339 : : /* Skip unless there's a DISTINCT or ORDER BY clause */
329 3340 [ + + + + ]: 1650 : if (aggref->aggdistinct == NIL && aggref->aggorder == NIL)
3341 : 150 : continue;
3342 : :
3343 : : /* Additional safety checks are needed if there's a FILTER clause */
3344 [ + + ]: 1500 : if (aggref->aggfilter != NULL)
3345 : : {
3346 : : ListCell *lc2;
3347 : 27 : bool allow_presort = true;
3348 : :
3349 : : /*
3350 : : * When the Aggref has a FILTER clause, it's possible that the
3351 : : * filter removes rows that cannot be sorted because the
3352 : : * expression to sort by results in an error during its
3353 : : * evaluation. This is a problem for presorting as that happens
3354 : : * before the FILTER, whereas without presorting, the Aggregate
3355 : : * node will apply the FILTER *before* sorting. So that we never
3356 : : * try to sort anything that might error, here we aim to skip over
3357 : : * any Aggrefs with arguments with expressions which, when
3358 : : * evaluated, could cause an ERROR. Vars and Consts are ok. There
3359 : : * may be more cases that should be allowed, but more thought
3360 : : * needs to be given. Err on the side of caution.
3361 : : */
3362 [ + - + + : 51 : foreach(lc2, aggref->args)
+ + ]
3363 : : {
3364 : 36 : TargetEntry *tle = (TargetEntry *) lfirst(lc2);
3365 : 36 : Expr *expr = tle->expr;
3366 : :
3367 [ + + ]: 42 : while (IsA(expr, RelabelType))
3368 : 6 : expr = (Expr *) (castNode(RelabelType, expr))->arg;
3369 : :
3370 : : /* Common case, Vars and Consts are ok */
3371 [ + + + + ]: 36 : if (IsA(expr, Var) || IsA(expr, Const))
3372 : 24 : continue;
3373 : :
3374 : : /* Unsupported. Don't try to presort for this Aggref */
3375 : 12 : allow_presort = false;
3376 : 12 : break;
3377 : : }
3378 : :
3379 : : /* Skip unsupported Aggrefs */
3380 [ + + ]: 27 : if (!allow_presort)
3381 : 12 : continue;
3382 : : }
3383 : :
3384 : 1488 : unprocessed_aggs = bms_add_member(unprocessed_aggs,
3385 : : foreach_current_index(lc));
3386 : : }
3387 : :
3388 : : /*
3389 : : * Now process all the unprocessed_aggs to find the best set of pathkeys
3390 : : * for the given set of aggregates.
3391 : : *
3392 : : * On the first outer loop here 'bestaggs' will be empty. We'll populate
3393 : : * this during the first loop using the pathkeys for the very first
3394 : : * AggInfo then taking any stronger pathkeys from any other AggInfos with
3395 : : * a more strict set of compatible pathkeys. Once the outer loop is
3396 : : * complete, we mark off all the aggregates with compatible pathkeys then
3397 : : * remove those from the unprocessed_aggs and repeat the process to try to
3398 : : * find another set of pathkeys that are suitable for a larger number of
3399 : : * aggregates. The outer loop will stop when there are not enough
3400 : : * unprocessed aggregates for it to be possible to find a set of pathkeys
3401 : : * to suit a larger number of aggregates.
3402 : : */
1321 3403 : 1440 : bestpathkeys = NIL;
3404 : 1440 : bestaggs = NULL;
3405 [ + + ]: 2847 : while (bms_num_members(unprocessed_aggs) > bms_num_members(bestaggs))
3406 : : {
3407 : 1407 : Bitmapset *aggindexes = NULL;
3408 : 1407 : List *currpathkeys = NIL;
3409 : :
3410 : 1407 : i = -1;
3411 [ + + ]: 3048 : while ((i = bms_next_member(unprocessed_aggs, i)) >= 0)
3412 : : {
3413 : 1641 : AggInfo *agginfo = list_nth_node(AggInfo, root->agginfos, i);
3414 : 1641 : Aggref *aggref = linitial_node(Aggref, agginfo->aggrefs);
3415 : : List *sortlist;
3416 : : List *pathkeys;
3417 : :
3418 [ + + ]: 1641 : if (aggref->aggdistinct != NIL)
3419 : 362 : sortlist = aggref->aggdistinct;
3420 : : else
3421 : 1279 : sortlist = aggref->aggorder;
3422 : :
1153 3423 : 1641 : pathkeys = make_pathkeys_for_sortclauses(root, sortlist,
3424 : : aggref->args);
3425 : :
3426 : : /*
3427 : : * Ignore Aggrefs which have volatile functions in their ORDER BY
3428 : : * or DISTINCT clause.
3429 : : */
3430 [ + + ]: 1641 : if (has_volatile_pathkey(pathkeys))
3431 : : {
3432 : 9 : unprocessed_aggs = bms_del_member(unprocessed_aggs, i);
3433 : 9 : continue;
3434 : : }
3435 : :
3436 : : /*
3437 : : * When not set yet, take the pathkeys from the first unprocessed
3438 : : * aggregate.
3439 : : */
1321 3440 [ + + ]: 1632 : if (currpathkeys == NIL)
3441 : : {
1153 3442 : 1404 : currpathkeys = pathkeys;
3443 : :
3444 : : /* include the GROUP BY pathkeys, if they exist */
1321 3445 [ + + ]: 1404 : if (grouppathkeys != NIL)
3446 : 138 : currpathkeys = append_pathkeys(list_copy(grouppathkeys),
3447 : : currpathkeys);
3448 : :
3449 : : /* record that we found pathkeys for this aggregate */
3450 : 1404 : aggindexes = bms_add_member(aggindexes, i);
3451 : : }
3452 : : else
3453 : : {
3454 : : /* now look for a stronger set of matching pathkeys */
3455 : :
3456 : : /* include the GROUP BY pathkeys, if they exist */
3457 [ + + ]: 228 : if (grouppathkeys != NIL)
3458 : 144 : pathkeys = append_pathkeys(list_copy(grouppathkeys),
3459 : : pathkeys);
3460 : :
3461 : : /* are 'pathkeys' compatible or better than 'currpathkeys'? */
3462 [ + + + - ]: 228 : switch (compare_pathkeys(currpathkeys, pathkeys))
3463 : : {
3464 : 6 : case PATHKEYS_BETTER2:
3465 : : /* 'pathkeys' are stronger, use these ones instead */
3466 : 6 : currpathkeys = pathkeys;
3467 : : pg_fallthrough;
3468 : :
3469 : 33 : case PATHKEYS_BETTER1:
3470 : : /* 'pathkeys' are less strict */
3471 : : pg_fallthrough;
3472 : :
3473 : : case PATHKEYS_EQUAL:
3474 : : /* mark this aggregate as covered by 'currpathkeys' */
3475 : 33 : aggindexes = bms_add_member(aggindexes, i);
3476 : 33 : break;
3477 : :
3478 : 195 : case PATHKEYS_DIFFERENT:
3479 : 195 : break;
3480 : : }
3481 : : }
3482 : : }
3483 : :
3484 : : /* remove the aggregates that we've just processed */
3485 : 1407 : unprocessed_aggs = bms_del_members(unprocessed_aggs, aggindexes);
3486 : :
3487 : : /*
3488 : : * If this pass included more aggregates than the previous best then
3489 : : * use these ones as the best set.
3490 : : */
3491 [ + + ]: 1407 : if (bms_num_members(aggindexes) > bms_num_members(bestaggs))
3492 : : {
3493 : 1353 : bestaggs = aggindexes;
3494 : 1353 : bestpathkeys = currpathkeys;
3495 : : }
3496 : : }
3497 : :
3498 : : /*
3499 : : * If we found any ordered aggregates, update root->group_pathkeys to add
3500 : : * the best set of aggregate pathkeys. Note that bestpathkeys includes
3501 : : * the original GROUP BY pathkeys already.
3502 : : */
1152 tgl@sss.pgh.pa.us 3503 [ + + ]: 1440 : if (bestpathkeys != NIL)
3504 : 1323 : root->group_pathkeys = bestpathkeys;
3505 : :
3506 : : /*
3507 : : * Now that we've found the best set of aggregates we can set the
3508 : : * presorted flag to indicate to the executor that it needn't bother
3509 : : * performing a sort for these Aggrefs. We're able to do this now as
3510 : : * there's no chance of a Hash Aggregate plan as create_grouping_paths
3511 : : * will not mark the GROUP BY as GROUPING_CAN_USE_HASH due to the presence
3512 : : * of ordered aggregates.
3513 : : */
1321 drowley@postgresql.o 3514 : 1440 : i = -1;
3515 [ + + ]: 2811 : while ((i = bms_next_member(bestaggs, i)) >= 0)
3516 : : {
3517 : 1371 : AggInfo *agginfo = list_nth_node(AggInfo, root->agginfos, i);
3518 : :
3519 [ + - + + : 2751 : foreach(lc, agginfo->aggrefs)
+ + ]
3520 : : {
3521 : 1380 : Aggref *aggref = lfirst_node(Aggref, lc);
3522 : :
3523 : 1380 : aggref->aggpresorted = true;
3524 : : }
3525 : : }
3526 : : }
3527 : :
3528 : : /*
3529 : : * Compute query_pathkeys and other pathkeys during plan generation
3530 : : */
3531 : : static void
4703 tgl@sss.pgh.pa.us 3532 : 282264 : standard_qp_callback(PlannerInfo *root, void *extra)
3533 : : {
3534 : 282264 : Query *parse = root->parse;
3535 : 282264 : standard_qp_extra *qp_extra = (standard_qp_extra *) extra;
2545 3536 : 282264 : List *tlist = root->processed_tlist;
4703 3537 : 282264 : List *activeWindows = qp_extra->activeWindows;
3538 : :
3539 : : /*
3540 : : * Calculate pathkeys that represent grouping/ordering and/or ordered
3541 : : * aggregate requirements.
3542 : : */
1152 3543 [ + + ]: 282264 : if (qp_extra->gset_data)
3544 : : {
3545 : : /*
3546 : : * With grouping sets, just use the first RollupData's groupClause. We
3547 : : * don't make any effort to optimize grouping clauses when there are
3548 : : * grouping sets, nor can we combine aggregate ordering keys with
3549 : : * grouping.
3550 : : */
3551 : 516 : List *rollups = qp_extra->gset_data->rollups;
3552 [ + + ]: 516 : List *groupClause = (rollups ? linitial_node(RollupData, rollups)->groupClause : NIL);
3553 : :
3554 [ + - ]: 516 : if (grouping_is_sortable(groupClause))
3555 : : {
3556 : : bool sortable;
3557 : :
3558 : : /*
3559 : : * The groupClause is logically below the grouping step. So if
3560 : : * there is an RTE entry for the grouping step, we need to remove
3561 : : * its RT index from the sort expressions before we make PathKeys
3562 : : * for them.
3563 : : */
551 rguo@postgresql.org 3564 : 516 : root->group_pathkeys =
3565 : 516 : make_pathkeys_for_sortclauses_extended(root,
3566 : : &groupClause,
3567 : : tlist,
3568 : : false,
3569 : 516 : parse->hasGroupRTE,
3570 : : &sortable,
3571 : : false);
3572 [ - + ]: 516 : Assert(sortable);
1152 tgl@sss.pgh.pa.us 3573 : 516 : root->num_groupby_pathkeys = list_length(root->group_pathkeys);
3574 : : }
3575 : : else
3576 : : {
1152 tgl@sss.pgh.pa.us 3577 :UBC 0 : root->group_pathkeys = NIL;
3578 : 0 : root->num_groupby_pathkeys = 0;
3579 : : }
3580 : : }
1152 tgl@sss.pgh.pa.us 3581 [ + + + + ]:CBC 281748 : else if (parse->groupClause || root->numOrderedAggs > 0)
3582 : 3398 : {
3583 : : /*
3584 : : * With a plain GROUP BY list, we can remove any grouping items that
3585 : : * are proven redundant by EquivalenceClass processing. For example,
3586 : : * we can remove y given "WHERE x = y GROUP BY x, y". These aren't
3587 : : * especially common cases, but they're nearly free to detect. Note
3588 : : * that we remove redundant items from processed_groupClause but not
3589 : : * the original parse->groupClause.
3590 : : */
3591 : : bool sortable;
3592 : :
3593 : : /*
3594 : : * Convert group clauses into pathkeys. Set the ec_sortref field of
3595 : : * EquivalenceClass'es if it's not set yet.
3596 : : */
3597 : 3398 : root->group_pathkeys =
3598 : 3398 : make_pathkeys_for_sortclauses_extended(root,
3599 : : &root->processed_groupClause,
3600 : : tlist,
3601 : : true,
3602 : : false,
3603 : : &sortable,
3604 : : true);
3605 [ - + ]: 3398 : if (!sortable)
3606 : : {
3607 : : /* Can't sort; no point in considering aggregate ordering either */
1152 tgl@sss.pgh.pa.us 3608 :UBC 0 : root->group_pathkeys = NIL;
3609 : 0 : root->num_groupby_pathkeys = 0;
3610 : : }
3611 : : else
3612 : : {
1152 tgl@sss.pgh.pa.us 3613 :CBC 3398 : root->num_groupby_pathkeys = list_length(root->group_pathkeys);
3614 : : /* If we have ordered aggs, consider adding onto group_pathkeys */
3615 [ + + ]: 3398 : if (root->numOrderedAggs > 0)
3616 : 1443 : adjust_group_pathkeys_for_groupagg(root);
3617 : : }
3618 : : }
3619 : : else
3620 : : {
4703 3621 : 278350 : root->group_pathkeys = NIL;
1321 drowley@postgresql.o 3622 : 278350 : root->num_groupby_pathkeys = 0;
3623 : : }
3624 : :
3625 : : /* We consider only the first (bottom) window in pathkeys logic */
4703 tgl@sss.pgh.pa.us 3626 [ + + ]: 282264 : if (activeWindows != NIL)
3627 : : {
3113 3628 : 1338 : WindowClause *wc = linitial_node(WindowClause, activeWindows);
3629 : :
4703 3630 : 1338 : root->window_pathkeys = make_pathkeys_for_window(root,
3631 : : wc,
3632 : : tlist);
3633 : : }
3634 : : else
3635 : 280926 : root->window_pathkeys = NIL;
3636 : :
3637 : : /*
3638 : : * As with GROUP BY, we can discard any DISTINCT items that are proven
3639 : : * redundant by EquivalenceClass processing. The non-redundant list is
3640 : : * kept in root->processed_distinctClause, leaving the original
3641 : : * parse->distinctClause alone.
3642 : : */
1152 3643 [ + + ]: 282264 : if (parse->distinctClause)
3644 : : {
3645 : : bool sortable;
3646 : :
3647 : : /* Make a copy since pathkey processing can modify the list */
3648 : 1606 : root->processed_distinctClause = list_copy(parse->distinctClause);
4703 3649 : 1606 : root->distinct_pathkeys =
1152 3650 : 1606 : make_pathkeys_for_sortclauses_extended(root,
3651 : : &root->processed_distinctClause,
3652 : : tlist,
3653 : : true,
3654 : : false,
3655 : : &sortable,
3656 : : false);
3657 [ + + ]: 1606 : if (!sortable)
3658 : 3 : root->distinct_pathkeys = NIL;
3659 : : }
3660 : : else
4703 3661 : 280658 : root->distinct_pathkeys = NIL;
3662 : :
3663 : 282264 : root->sort_pathkeys =
3664 : 282264 : make_pathkeys_for_sortclauses(root,
3665 : : parse->sortClause,
3666 : : tlist);
3667 : :
3668 : : /* setting setop_pathkeys might be useful to the union planner */
451 3669 [ + + ]: 282264 : if (qp_extra->setop != NULL)
3670 : : {
3671 : : List *groupClauses;
3672 : : bool sortable;
3673 : :
663 rhaas@postgresql.org 3674 : 6460 : groupClauses = generate_setop_child_grouplist(qp_extra->setop, tlist);
3675 : :
3676 : 6460 : root->setop_pathkeys =
3677 : 6460 : make_pathkeys_for_sortclauses_extended(root,
3678 : : &groupClauses,
3679 : : tlist,
3680 : : false,
3681 : : false,
3682 : : &sortable,
3683 : : false);
3684 [ + + ]: 6460 : if (!sortable)
3685 : 104 : root->setop_pathkeys = NIL;
3686 : : }
3687 : : else
3688 : 275804 : root->setop_pathkeys = NIL;
3689 : :
3690 : : /*
3691 : : * Figure out whether we want a sorted result from query_planner.
3692 : : *
3693 : : * If we have a sortable GROUP BY clause, then we want a result sorted
3694 : : * properly for grouping. Otherwise, if we have window functions to
3695 : : * evaluate, we try to sort for the first window. Otherwise, if there's a
3696 : : * sortable DISTINCT clause that's more rigorous than the ORDER BY clause,
3697 : : * we try to produce output that's sufficiently well sorted for the
3698 : : * DISTINCT. Otherwise, if there is an ORDER BY clause, we want to sort
3699 : : * by the ORDER BY clause. Otherwise, if we're a subquery being planned
3700 : : * for a set operation which can benefit from presorted results and have a
3701 : : * sortable targetlist, we want to sort by the target list.
3702 : : *
3703 : : * Note: if we have both ORDER BY and GROUP BY, and ORDER BY is a superset
3704 : : * of GROUP BY, it would be tempting to request sort by ORDER BY --- but
3705 : : * that might just leave us failing to exploit an available sort order at
3706 : : * all. Needs more thought. The choice for DISTINCT versus ORDER BY is
3707 : : * much easier, since we know that the parser ensured that one is a
3708 : : * superset of the other.
3709 : : */
4703 tgl@sss.pgh.pa.us 3710 [ + + ]: 282264 : if (root->group_pathkeys)
3711 : 3695 : root->query_pathkeys = root->group_pathkeys;
3712 [ + + ]: 278569 : else if (root->window_pathkeys)
3713 : 1055 : root->query_pathkeys = root->window_pathkeys;
3714 [ + + ]: 555028 : else if (list_length(root->distinct_pathkeys) >
3715 : 277514 : list_length(root->sort_pathkeys))
3716 : 1358 : root->query_pathkeys = root->distinct_pathkeys;
3717 [ + + ]: 276156 : else if (root->sort_pathkeys)
3718 : 37957 : root->query_pathkeys = root->sort_pathkeys;
663 rhaas@postgresql.org 3719 [ + + ]: 238199 : else if (root->setop_pathkeys != NIL)
3720 : 5760 : root->query_pathkeys = root->setop_pathkeys;
3721 : : else
4703 tgl@sss.pgh.pa.us 3722 : 232439 : root->query_pathkeys = NIL;
3723 : 282264 : }
3724 : :
3725 : : /*
3726 : : * Estimate number of groups produced by grouping clauses (1 if not grouping)
3727 : : *
3728 : : * path_rows: number of output rows from scan/join step
3729 : : * gd: grouping sets data including list of grouping sets and their clauses
3730 : : * target_list: target list containing group clause references
3731 : : *
3732 : : * If doing grouping sets, we also annotate the gsets data with the estimates
3733 : : * for each set and each individual rollup list, with a view to later
3734 : : * determining whether some combination of them could be hashed instead.
3735 : : */
3736 : : static double
3660 3737 : 27719 : get_number_of_groups(PlannerInfo *root,
3738 : : double path_rows,
3739 : : grouping_sets_data *gd,
3740 : : List *target_list)
3741 : : {
5877 3742 : 27719 : Query *parse = root->parse;
3743 : : double dNumGroups;
3744 : :
3660 3745 [ + + ]: 27719 : if (parse->groupClause)
3746 : : {
3747 : : List *groupExprs;
3748 : :
3749 [ + + ]: 5223 : if (parse->groupingSets)
3750 : : {
3751 : : /* Add up the estimates for each grouping set */
3752 : : ListCell *lc;
3753 : :
3224 bruce@momjian.us 3754 [ - + ]: 477 : Assert(gd); /* keep Coverity happy */
3755 : :
3660 tgl@sss.pgh.pa.us 3756 : 477 : dNumGroups = 0;
3757 : :
3275 rhodiumtoad@postgres 3758 [ + + + + : 1270 : foreach(lc, gd->rollups)
+ + ]
3759 : : {
3113 tgl@sss.pgh.pa.us 3760 : 793 : RollupData *rollup = lfirst_node(RollupData, lc);
3761 : : ListCell *lc2;
3762 : : ListCell *lc3;
3763 : :
3275 rhodiumtoad@postgres 3764 : 793 : groupExprs = get_sortgrouplist_exprs(rollup->groupClause,
3765 : : target_list);
3766 : :
3767 : 793 : rollup->numGroups = 0.0;
3768 : :
1257 drowley@postgresql.o 3769 [ + - + + : 2251 : forboth(lc2, rollup->gsets, lc3, rollup->gsets_data)
+ - + + +
+ + - +
+ ]
3770 : : {
3771 : 1458 : List *gset = (List *) lfirst(lc2);
3772 : 1458 : GroupingSetData *gs = lfirst_node(GroupingSetData, lc3);
3275 rhodiumtoad@postgres 3773 : 1458 : double numGroups = estimate_num_groups(root,
3774 : : groupExprs,
3775 : : path_rows,
3776 : : &gset,
3777 : : NULL);
3778 : :
3779 : 1458 : gs->numGroups = numGroups;
3780 : 1458 : rollup->numGroups += numGroups;
3781 : : }
3782 : :
3783 : 793 : dNumGroups += rollup->numGroups;
3784 : : }
3785 : :
3786 [ + + ]: 477 : if (gd->hash_sets_idx)
3787 : : {
3788 : : ListCell *lc2;
3789 : :
3790 : 18 : gd->dNumHashGroups = 0;
3791 : :
3792 : 18 : groupExprs = get_sortgrouplist_exprs(parse->groupClause,
3793 : : target_list);
3794 : :
3795 [ + - + + : 39 : forboth(lc, gd->hash_sets_idx, lc2, gd->unsortable_sets)
+ - + + +
+ + - +
+ ]
3796 : : {
3797 : 21 : List *gset = (List *) lfirst(lc);
3113 tgl@sss.pgh.pa.us 3798 : 21 : GroupingSetData *gs = lfirst_node(GroupingSetData, lc2);
3275 rhodiumtoad@postgres 3799 : 21 : double numGroups = estimate_num_groups(root,
3800 : : groupExprs,
3801 : : path_rows,
3802 : : &gset,
3803 : : NULL);
3804 : :
3805 : 21 : gs->numGroups = numGroups;
3806 : 21 : gd->dNumHashGroups += numGroups;
3807 : : }
3808 : :
3809 : 18 : dNumGroups += gd->dNumHashGroups;
3810 : : }
3811 : : }
3812 : : else
3813 : : {
3814 : : /* Plain GROUP BY -- estimate based on optimized groupClause */
1152 tgl@sss.pgh.pa.us 3815 : 4746 : groupExprs = get_sortgrouplist_exprs(root->processed_groupClause,
3816 : : target_list);
3817 : :
3660 3818 : 4746 : dNumGroups = estimate_num_groups(root, groupExprs, path_rows,
3819 : : NULL, NULL);
3820 : : }
3821 : : }
3822 [ + + ]: 22496 : else if (parse->groupingSets)
3823 : : {
3824 : : /* Empty grouping sets ... one result row for each one */
3825 : 30 : dNumGroups = list_length(parse->groupingSets);
3826 : : }
3827 [ - + - - ]: 22466 : else if (parse->hasAggs || root->hasHavingQual)
3828 : : {
3829 : : /* Plain aggregation, one result row */
3830 : 22466 : dNumGroups = 1;
3831 : : }
3832 : : else
3833 : : {
3834 : : /* Not grouping */
3660 tgl@sss.pgh.pa.us 3835 :UBC 0 : dNumGroups = 1;
3836 : : }
3837 : :
3660 tgl@sss.pgh.pa.us 3838 :CBC 27719 : return dNumGroups;
3839 : : }
3840 : :
3841 : : /*
3842 : : * create_grouping_paths
3843 : : *
3844 : : * Build a new upperrel containing Paths for grouping and/or aggregation.
3845 : : * Along the way, we also build an upperrel for Paths which are partially
3846 : : * grouped and/or aggregated. A partially grouped and/or aggregated path
3847 : : * needs a FinalizeAggregate node to complete the aggregation. Currently,
3848 : : * the only partially grouped paths we build are also partial paths; that
3849 : : * is, they need a Gather and then a FinalizeAggregate.
3850 : : *
3851 : : * input_rel: contains the source-data Paths
3852 : : * target: the pathtarget for the result Paths to compute
3853 : : * gd: grouping sets data including list of grouping sets and their clauses
3854 : : *
3855 : : * Note: all Paths in input_rel are expected to return the target computed
3856 : : * by make_group_input_target.
3857 : : */
3858 : : static RelOptInfo *
3859 : 23517 : create_grouping_paths(PlannerInfo *root,
3860 : : RelOptInfo *input_rel,
3861 : : PathTarget *target,
3862 : : bool target_parallel_safe,
3863 : : grouping_sets_data *gd)
3864 : : {
3865 : 23517 : Query *parse = root->parse;
3866 : : RelOptInfo *grouped_rel;
3867 : : RelOptInfo *partially_grouped_rel;
3868 : : AggClauseCosts agg_costs;
3869 : :
1937 heikki.linnakangas@i 3870 [ + - + - : 141102 : MemSet(&agg_costs, 0, sizeof(AggClauseCosts));
+ - + - +
+ ]
3871 : 23517 : get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &agg_costs);
3872 : :
3873 : : /*
3874 : : * Create grouping relation to hold fully aggregated grouping and/or
3875 : : * aggregation paths.
3876 : : */
2915 rhaas@postgresql.org 3877 : 23517 : grouped_rel = make_grouping_rel(root, input_rel, target,
3878 : : target_parallel_safe, parse->havingQual);
3879 : :
3880 : : /*
3881 : : * Create either paths for a degenerate grouping or paths for ordinary
3882 : : * grouping, as appropriate.
3883 : : */
2922 3884 [ + + ]: 23517 : if (is_degenerate_grouping(root))
2917 3885 : 21 : create_degenerate_grouping_paths(root, input_rel, grouped_rel);
3886 : : else
3887 : : {
3888 : 23496 : int flags = 0;
3889 : : GroupPathExtraData extra;
3890 : :
3891 : : /*
3892 : : * Determine whether it's possible to perform sort-based
3893 : : * implementations of grouping. (Note that if processed_groupClause
3894 : : * is empty, grouping_is_sortable() is trivially true, and all the
3895 : : * pathkeys_contained_in() tests will succeed too, so that we'll
3896 : : * consider every surviving input path.)
3897 : : *
3898 : : * If we have grouping sets, we might be able to sort some but not all
3899 : : * of them; in this case, we need can_sort to be true as long as we
3900 : : * must consider any sorted-input plan.
3901 : : */
3902 [ + + + + ]: 23496 : if ((gd && gd->rollups != NIL)
1152 tgl@sss.pgh.pa.us 3903 [ + + ]: 22992 : || grouping_is_sortable(root->processed_groupClause))
2917 rhaas@postgresql.org 3904 : 23493 : flags |= GROUPING_CAN_USE_SORT;
3905 : :
3906 : : /*
3907 : : * Determine whether we should consider hash-based implementations of
3908 : : * grouping.
3909 : : *
3910 : : * Hashed aggregation only applies if we're grouping. If we have
3911 : : * grouping sets, some groups might be hashable but others not; in
3912 : : * this case we set can_hash true as long as there is nothing globally
3913 : : * preventing us from hashing (and we should therefore consider plans
3914 : : * with hashes).
3915 : : *
3916 : : * Executor doesn't support hashed aggregation with DISTINCT or ORDER
3917 : : * BY aggregates. (Doing so would imply storing *all* the input
3918 : : * values in the hash table, and/or running many sorts in parallel,
3919 : : * either of which seems like a certain loser.) We similarly don't
3920 : : * support ordered-set aggregates in hashed aggregation, but that case
3921 : : * is also included in the numOrderedAggs count.
3922 : : *
3923 : : * Note: grouping_is_hashable() is much more expensive to check than
3924 : : * the other gating conditions, so we want to do it last.
3925 : : */
3926 [ + + ]: 23496 : if ((parse->groupClause != NIL &&
1937 heikki.linnakangas@i 3927 [ + + + + : 4968 : root->numOrderedAggs == 0 &&
+ + ]
1152 tgl@sss.pgh.pa.us 3928 : 2414 : (gd ? gd->any_hashable : grouping_is_hashable(root->processed_groupClause))))
2917 rhaas@postgresql.org 3929 : 2411 : flags |= GROUPING_CAN_USE_HASH;
3930 : :
3931 : : /*
3932 : : * Determine whether partial aggregation is possible.
3933 : : */
1937 heikki.linnakangas@i 3934 [ + + ]: 23496 : if (can_partial_agg(root))
2917 rhaas@postgresql.org 3935 : 20681 : flags |= GROUPING_CAN_PARTIAL_AGG;
3936 : :
2915 3937 : 23496 : extra.flags = flags;
3938 : 23496 : extra.target_parallel_safe = target_parallel_safe;
3939 : 23496 : extra.havingQual = parse->havingQual;
3940 : 23496 : extra.targetList = parse->targetList;
3941 : 23496 : extra.partial_costs_set = false;
3942 : :
3943 : : /*
3944 : : * Determine whether partitionwise aggregation is in theory possible.
3945 : : * It can be disabled by the user, and for now, we don't try to
3946 : : * support grouping sets. create_ordinary_grouping_paths() will check
3947 : : * additional conditions, such as whether input_rel is partitioned.
3948 : : */
3949 [ + + + + ]: 23496 : if (enable_partitionwise_aggregate && !parse->groupingSets)
3950 : 350 : extra.patype = PARTITIONWISE_AGGREGATE_FULL;
3951 : : else
3952 : 23146 : extra.patype = PARTITIONWISE_AGGREGATE_NONE;
3953 : :
2917 3954 : 23496 : create_ordinary_grouping_paths(root, input_rel, grouped_rel,
3955 : : &agg_costs, gd, &extra,
3956 : : &partially_grouped_rel);
3957 : : }
3958 : :
2922 3959 : 23514 : set_cheapest(grouped_rel);
3960 : 23514 : return grouped_rel;
3961 : : }
3962 : :
3963 : : /*
3964 : : * make_grouping_rel
3965 : : *
3966 : : * Create a new grouping rel and set basic properties.
3967 : : *
3968 : : * input_rel represents the underlying scan/join relation.
3969 : : * target is the output expected from the grouping relation.
3970 : : */
3971 : : static RelOptInfo *
2915 3972 : 24600 : make_grouping_rel(PlannerInfo *root, RelOptInfo *input_rel,
3973 : : PathTarget *target, bool target_parallel_safe,
3974 : : Node *havingQual)
3975 : : {
3976 : : RelOptInfo *grouped_rel;
3977 : :
3978 [ + + + + : 24600 : if (IS_OTHER_REL(input_rel))
- + ]
3979 : : {
3980 : 1083 : grouped_rel = fetch_upper_rel(root, UPPERREL_GROUP_AGG,
3981 : : input_rel->relids);
3982 : 1083 : grouped_rel->reloptkind = RELOPT_OTHER_UPPER_REL;
3983 : : }
3984 : : else
3985 : : {
3986 : : /*
3987 : : * By tradition, the relids set for the main grouping relation is
3988 : : * NULL. (This could be changed, but might require adjustments
3989 : : * elsewhere.)
3990 : : */
3991 : 23517 : grouped_rel = fetch_upper_rel(root, UPPERREL_GROUP_AGG, NULL);
3992 : : }
3993 : :
3994 : : /* Set target. */
3995 : 24600 : grouped_rel->reltarget = target;
3996 : :
3997 : : /*
3998 : : * If the input relation is not parallel-safe, then the grouped relation
3999 : : * can't be parallel-safe, either. Otherwise, it's parallel-safe if the
4000 : : * target list and HAVING quals are parallel-safe.
4001 : : */
4002 [ + + + + : 39407 : if (input_rel->consider_parallel && target_parallel_safe &&
+ + ]
103 peter@eisentraut.org 4003 :GNC 14807 : is_parallel_safe(root, havingQual))
2915 rhaas@postgresql.org 4004 :CBC 14795 : grouped_rel->consider_parallel = true;
4005 : :
4006 : : /* Assume that the same path generation strategies are allowed */
46 rhaas@postgresql.org 4007 :GNC 24600 : grouped_rel->pgs_mask = input_rel->pgs_mask;
4008 : :
4009 : : /*
4010 : : * If the input rel belongs to a single FDW, so does the grouped rel.
4011 : : */
2915 rhaas@postgresql.org 4012 :CBC 24600 : grouped_rel->serverid = input_rel->serverid;
4013 : 24600 : grouped_rel->userid = input_rel->userid;
4014 : 24600 : grouped_rel->useridiscurrent = input_rel->useridiscurrent;
4015 : 24600 : grouped_rel->fdwroutine = input_rel->fdwroutine;
4016 : :
4017 : 24600 : return grouped_rel;
4018 : : }
4019 : :
4020 : : /*
4021 : : * is_degenerate_grouping
4022 : : *
4023 : : * A degenerate grouping is one in which the query has a HAVING qual and/or
4024 : : * grouping sets, but no aggregates and no GROUP BY (which implies that the
4025 : : * grouping sets are all empty).
4026 : : */
4027 : : static bool
2922 4028 : 23517 : is_degenerate_grouping(PlannerInfo *root)
4029 : : {
4030 : 23517 : Query *parse = root->parse;
4031 : :
4032 [ + + ]: 22892 : return (root->hasHavingQual || parse->groupingSets) &&
4033 [ + + + + : 46409 : !parse->hasAggs && parse->groupClause == NIL;
+ + ]
4034 : : }
4035 : :
4036 : : /*
4037 : : * create_degenerate_grouping_paths
4038 : : *
4039 : : * When the grouping is degenerate (see is_degenerate_grouping), we are
4040 : : * supposed to emit either zero or one row for each grouping set depending on
4041 : : * whether HAVING succeeds. Furthermore, there cannot be any variables in
4042 : : * either HAVING or the targetlist, so we actually do not need the FROM table
4043 : : * at all! We can just throw away the plan-so-far and generate a Result node.
4044 : : * This is a sufficiently unusual corner case that it's not worth contorting
4045 : : * the structure of this module to avoid having to generate the earlier paths
4046 : : * in the first place.
4047 : : */
4048 : : static void
4049 : 21 : create_degenerate_grouping_paths(PlannerInfo *root, RelOptInfo *input_rel,
4050 : : RelOptInfo *grouped_rel)
4051 : : {
4052 : 21 : Query *parse = root->parse;
4053 : : int nrows;
4054 : : Path *path;
4055 : :
4056 : 21 : nrows = list_length(parse->groupingSets);
4057 [ + + ]: 21 : if (nrows > 1)
4058 : : {
4059 : : /*
4060 : : * Doesn't seem worthwhile writing code to cons up a generate_series
4061 : : * or a values scan to emit multiple rows. Instead just make N clones
4062 : : * and append them. (With a volatile HAVING clause, this means you
4063 : : * might get between 0 and N output rows. Offhand I think that's
4064 : : * desired.)
4065 : : */
33 rhaas@postgresql.org 4066 :GNC 6 : AppendPathInput append = {0};
4067 : :
2922 rhaas@postgresql.org 4068 [ + + ]:GBC 18 : while (--nrows >= 0)
4069 : : {
4070 : : path = (Path *)
2603 tgl@sss.pgh.pa.us 4071 : 12 : create_group_result_path(root, grouped_rel,
4072 : 12 : grouped_rel->reltarget,
4073 : 12 : (List *) parse->havingQual);
33 rhaas@postgresql.org 4074 :GNC 12 : append.subpaths = lappend(append.subpaths, path);
4075 : : }
4076 : : path = (Path *)
2899 alvherre@alvh.no-ip. 4077 :GBC 6 : create_append_path(root,
4078 : : grouped_rel,
4079 : : append,
4080 : : NIL,
4081 : : NULL,
4082 : : 0,
4083 : : false,
4084 : : -1);
4085 : : }
4086 : : else
4087 : : {
4088 : : /* No grouping sets, or just one, so one output row */
4089 : : path = (Path *)
2603 tgl@sss.pgh.pa.us 4090 :CBC 15 : create_group_result_path(root, grouped_rel,
4091 : 15 : grouped_rel->reltarget,
4092 : 15 : (List *) parse->havingQual);
4093 : : }
4094 : :
2922 rhaas@postgresql.org 4095 : 21 : add_path(grouped_rel, path);
4096 : 21 : }
4097 : :
4098 : : /*
4099 : : * create_ordinary_grouping_paths
4100 : : *
4101 : : * Create grouping paths for the ordinary (that is, non-degenerate) case.
4102 : : *
4103 : : * We need to consider sorted and hashed aggregation in the same function,
4104 : : * because otherwise (1) it would be harder to throw an appropriate error
4105 : : * message if neither way works, and (2) we should not allow hashtable size
4106 : : * considerations to dissuade us from using hashing if sorting is not possible.
4107 : : *
4108 : : * *partially_grouped_rel_p will be set to the partially grouped rel which this
4109 : : * function creates, or to NULL if it doesn't create one.
4110 : : */
4111 : : static void
4112 : 24579 : create_ordinary_grouping_paths(PlannerInfo *root, RelOptInfo *input_rel,
4113 : : RelOptInfo *grouped_rel,
4114 : : const AggClauseCosts *agg_costs,
4115 : : grouping_sets_data *gd,
4116 : : GroupPathExtraData *extra,
4117 : : RelOptInfo **partially_grouped_rel_p)
4118 : : {
2917 4119 : 24579 : RelOptInfo *partially_grouped_rel = NULL;
2915 4120 : 24579 : PartitionwiseAggregateType patype = PARTITIONWISE_AGGREGATE_NONE;
4121 : :
4122 : : /*
4123 : : * If this is the topmost grouping relation or if the parent relation is
4124 : : * doing some form of partitionwise aggregation, then we may be able to do
4125 : : * it at this level also. However, if the input relation is not
4126 : : * partitioned, partitionwise aggregate is impossible.
4127 : : */
4128 [ + + ]: 24579 : if (extra->patype != PARTITIONWISE_AGGREGATE_NONE &&
2565 tgl@sss.pgh.pa.us 4129 [ + + + - : 1433 : IS_PARTITIONED_REL(input_rel))
+ + + - +
+ ]
4130 : : {
4131 : : /*
4132 : : * If this is the topmost relation or if the parent relation is doing
4133 : : * full partitionwise aggregation, then we can do full partitionwise
4134 : : * aggregation provided that the GROUP BY clause contains all of the
4135 : : * partitioning columns at this level and the collation used by GROUP
4136 : : * BY matches the partitioning collation. Otherwise, we can do at
4137 : : * most partial partitionwise aggregation. But if partial aggregation
4138 : : * is not supported in general then we can't use it for partitionwise
4139 : : * aggregation either.
4140 : : *
4141 : : * Check parse->groupClause not processed_groupClause, because it's
4142 : : * okay if some of the partitioning columns were proved redundant.
4143 : : */
2915 rhaas@postgresql.org 4144 [ + + + + ]: 820 : if (extra->patype == PARTITIONWISE_AGGREGATE_FULL &&
4145 : 386 : group_by_has_partkey(input_rel, extra->targetList,
4146 : 386 : root->parse->groupClause))
4147 : 244 : patype = PARTITIONWISE_AGGREGATE_FULL;
4148 [ + + ]: 190 : else if ((extra->flags & GROUPING_CAN_PARTIAL_AGG) != 0)
4149 : 169 : patype = PARTITIONWISE_AGGREGATE_PARTIAL;
4150 : : else
4151 : 21 : patype = PARTITIONWISE_AGGREGATE_NONE;
4152 : : }
4153 : :
4154 : : /*
4155 : : * Before generating paths for grouped_rel, we first generate any possible
4156 : : * partially grouped paths; that way, later code can easily consider both
4157 : : * parallel and non-parallel approaches to grouping.
4158 : : */
4159 [ + + ]: 24579 : if ((extra->flags & GROUPING_CAN_PARTIAL_AGG) != 0)
4160 : : {
4161 : : bool force_rel_creation;
4162 : :
4163 : : /*
4164 : : * If we're doing partitionwise aggregation at this level, force
4165 : : * creation of a partially_grouped_rel so we can add partitionwise
4166 : : * paths to it.
4167 : : */
4168 : 21728 : force_rel_creation = (patype == PARTITIONWISE_AGGREGATE_PARTIAL);
4169 : :
4170 : : partially_grouped_rel =
2917 4171 : 21728 : create_partial_grouping_paths(root,
4172 : : grouped_rel,
4173 : : input_rel,
4174 : : gd,
4175 : : extra,
4176 : : force_rel_creation);
4177 : : }
4178 : :
4179 : : /* Set out parameter. */
2915 4180 : 24579 : *partially_grouped_rel_p = partially_grouped_rel;
4181 : :
4182 : : /* Apply partitionwise aggregation technique, if possible. */
4183 [ + + ]: 24579 : if (patype != PARTITIONWISE_AGGREGATE_NONE)
4184 : 413 : create_partitionwise_grouping_paths(root, input_rel, grouped_rel,
4185 : : partially_grouped_rel, agg_costs,
4186 : : gd, patype, extra);
4187 : :
4188 : : /* If we are doing partial aggregation only, return. */
4189 [ + + ]: 24579 : if (extra->patype == PARTITIONWISE_AGGREGATE_PARTIAL)
4190 : : {
4191 [ - + ]: 429 : Assert(partially_grouped_rel);
4192 : :
4193 [ + - ]: 429 : if (partially_grouped_rel->pathlist)
4194 : 429 : set_cheapest(partially_grouped_rel);
4195 : :
4196 : 429 : return;
4197 : : }
4198 : :
4199 : : /* Gather any partially grouped partial paths. */
4200 [ + + + + ]: 24150 : if (partially_grouped_rel && partially_grouped_rel->partial_pathlist)
2917 4201 : 1387 : gather_grouping_paths(root, partially_grouped_rel);
4202 : :
4203 : : /* Now choose the best path(s) for partially_grouped_rel. */
158 rguo@postgresql.org 4204 [ + + + - ]:GNC 24150 : if (partially_grouped_rel && partially_grouped_rel->pathlist)
4205 : 1501 : set_cheapest(partially_grouped_rel);
4206 : :
4207 : : /* Build final grouping paths */
2917 rhaas@postgresql.org 4208 :CBC 24150 : add_paths_to_grouping_rel(root, input_rel, grouped_rel,
4209 : : partially_grouped_rel, agg_costs, gd,
4210 : : extra);
4211 : :
4212 : : /* Give a helpful error if we failed to find any implementation */
2970 4213 [ + + ]: 24150 : if (grouped_rel->pathlist == NIL)
4214 [ + - ]: 3 : ereport(ERROR,
4215 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4216 : : errmsg("could not implement GROUP BY"),
4217 : : errdetail("Some of the datatypes only support hashing, while others only support sorting.")));
4218 : :
4219 : : /*
4220 : : * If there is an FDW that's responsible for all baserels of the query,
4221 : : * let it consider adding ForeignPaths.
4222 : : */
4223 [ + + ]: 24147 : if (grouped_rel->fdwroutine &&
4224 [ + + ]: 169 : grouped_rel->fdwroutine->GetForeignUpperPaths)
4225 : 168 : grouped_rel->fdwroutine->GetForeignUpperPaths(root, UPPERREL_GROUP_AGG,
4226 : : input_rel, grouped_rel,
4227 : : extra);
4228 : :
4229 : : /* Let extensions possibly add some more paths */
4230 [ - + ]: 24147 : if (create_upper_paths_hook)
2970 rhaas@postgresql.org 4231 :UBC 0 : (*create_upper_paths_hook) (root, UPPERREL_GROUP_AGG,
4232 : : input_rel, grouped_rel,
4233 : : extra);
4234 : : }
4235 : :
4236 : : /*
4237 : : * For a given input path, consider the possible ways of doing grouping sets on
4238 : : * it, by combinations of hashing and sorting. This can be called multiple
4239 : : * times, so it's important that it not scribble on input. No result is
4240 : : * returned, but any generated paths are added to grouped_rel.
4241 : : */
4242 : : static void
2970 rhaas@postgresql.org 4243 :CBC 999 : consider_groupingsets_paths(PlannerInfo *root,
4244 : : RelOptInfo *grouped_rel,
4245 : : Path *path,
4246 : : bool is_sorted,
4247 : : bool can_hash,
4248 : : grouping_sets_data *gd,
4249 : : const AggClauseCosts *agg_costs,
4250 : : double dNumGroups)
4251 : : {
4252 : 999 : Query *parse = root->parse;
1694 tgl@sss.pgh.pa.us 4253 : 999 : Size hash_mem_limit = get_hash_memory_limit();
4254 : :
4255 : : /*
4256 : : * If we're not being offered sorted input, then only consider plans that
4257 : : * can be done entirely by hashing.
4258 : : *
4259 : : * We can hash everything if it looks like it'll fit in hash_mem. But if
4260 : : * the input is actually sorted despite not being advertised as such, we
4261 : : * prefer to make use of that in order to use less memory.
4262 : : *
4263 : : * If none of the grouping sets are sortable, then ignore the hash_mem
4264 : : * limit and generate a path anyway, since otherwise we'll just fail.
4265 : : */
2970 rhaas@postgresql.org 4266 [ + + ]: 999 : if (!is_sorted)
4267 : : {
4268 : 459 : List *new_rollups = NIL;
4269 : 459 : RollupData *unhashed_rollup = NULL;
4270 : : List *sets_data;
4271 : 459 : List *empty_sets_data = NIL;
4272 : 459 : List *empty_sets = NIL;
4273 : : ListCell *lc;
4274 : 459 : ListCell *l_start = list_head(gd->rollups);
4275 : 459 : AggStrategy strat = AGG_HASHED;
4276 : : double hashsize;
4277 : 459 : double exclude_groups = 0.0;
4278 : :
4279 [ - + ]: 459 : Assert(can_hash);
4280 : :
4281 : : /*
4282 : : * If the input is coincidentally sorted usefully (which can happen
4283 : : * even if is_sorted is false, since that only means that our caller
4284 : : * has set up the sorting for us), then save some hashtable space by
4285 : : * making use of that. But we need to watch out for degenerate cases:
4286 : : *
4287 : : * 1) If there are any empty grouping sets, then group_pathkeys might
4288 : : * be NIL if all non-empty grouping sets are unsortable. In this case,
4289 : : * there will be a rollup containing only empty groups, and the
4290 : : * pathkeys_contained_in test is vacuously true; this is ok.
4291 : : *
4292 : : * XXX: the above relies on the fact that group_pathkeys is generated
4293 : : * from the first rollup. If we add the ability to consider multiple
4294 : : * sort orders for grouping input, this assumption might fail.
4295 : : *
4296 : : * 2) If there are no empty sets and only unsortable sets, then the
4297 : : * rollups list will be empty (and thus l_start == NULL), and
4298 : : * group_pathkeys will be NIL; we must ensure that the vacuously-true
4299 : : * pathkeys_contained_in test doesn't cause us to crash.
4300 : : */
2916 rhodiumtoad@postgres 4301 [ + + + + ]: 915 : if (l_start != NULL &&
4302 : 456 : pathkeys_contained_in(root->group_pathkeys, path->pathkeys))
4303 : : {
2970 rhaas@postgresql.org 4304 : 18 : unhashed_rollup = lfirst_node(RollupData, l_start);
4305 : 18 : exclude_groups = unhashed_rollup->numGroups;
2435 tgl@sss.pgh.pa.us 4306 : 18 : l_start = lnext(gd->rollups, l_start);
4307 : : }
4308 : :
1937 heikki.linnakangas@i 4309 : 459 : hashsize = estimate_hashagg_tablesize(root,
4310 : : path,
4311 : : agg_costs,
4312 : : dNumGroups - exclude_groups);
4313 : :
4314 : : /*
4315 : : * gd->rollups is empty if we have only unsortable columns to work
4316 : : * with. Override hash_mem in that case; otherwise, we'll rely on the
4317 : : * sorted-input case to generate usable mixed paths.
4318 : : */
1694 tgl@sss.pgh.pa.us 4319 [ + + + - ]: 459 : if (hashsize > hash_mem_limit && gd->rollups)
2970 rhaas@postgresql.org 4320 : 9 : return; /* nope, won't fit */
4321 : :
4322 : : /*
4323 : : * We need to burst the existing rollups list into individual grouping
4324 : : * sets and recompute a groupClause for each set.
4325 : : */
4326 : 450 : sets_data = list_copy(gd->unsortable_sets);
4327 : :
2435 tgl@sss.pgh.pa.us 4328 [ + + + + : 1135 : for_each_cell(lc, gd->rollups, l_start)
+ + ]
4329 : : {
2970 rhaas@postgresql.org 4330 : 697 : RollupData *rollup = lfirst_node(RollupData, lc);
4331 : :
4332 : : /*
4333 : : * If we find an unhashable rollup that's not been skipped by the
4334 : : * "actually sorted" check above, we can't cope; we'd need sorted
4335 : : * input (with a different sort order) but we can't get that here.
4336 : : * So bail out; we'll get a valid path from the is_sorted case
4337 : : * instead.
4338 : : *
4339 : : * The mere presence of empty grouping sets doesn't make a rollup
4340 : : * unhashable (see preprocess_grouping_sets), we handle those
4341 : : * specially below.
4342 : : */
3275 rhodiumtoad@postgres 4343 [ + + ]: 697 : if (!rollup->hashable)
4344 : 12 : return;
4345 : :
2407 tgl@sss.pgh.pa.us 4346 : 685 : sets_data = list_concat(sets_data, rollup->gsets_data);
4347 : : }
3275 rhodiumtoad@postgres 4348 [ + - + + : 1767 : foreach(lc, sets_data)
+ + ]
4349 : : {
3113 tgl@sss.pgh.pa.us 4350 : 1329 : GroupingSetData *gs = lfirst_node(GroupingSetData, lc);
3275 rhodiumtoad@postgres 4351 : 1329 : List *gset = gs->set;
4352 : : RollupData *rollup;
4353 : :
4354 [ + + ]: 1329 : if (gset == NIL)
4355 : : {
4356 : : /* Empty grouping sets can't be hashed. */
4357 : 271 : empty_sets_data = lappend(empty_sets_data, gs);
4358 : 271 : empty_sets = lappend(empty_sets, NIL);
4359 : : }
4360 : : else
4361 : : {
4362 : 1058 : rollup = makeNode(RollupData);
4363 : :
647 akorotkov@postgresql 4364 : 1058 : rollup->groupClause = preprocess_groupclause(root, gset);
3275 rhodiumtoad@postgres 4365 : 1058 : rollup->gsets_data = list_make1(gs);
4366 : 1058 : rollup->gsets = remap_to_groupclause_idx(rollup->groupClause,
4367 : : rollup->gsets_data,
4368 : : gd->tleref_to_colnum_map);
4369 : 1058 : rollup->numGroups = gs->numGroups;
4370 : 1058 : rollup->hashable = true;
4371 : 1058 : rollup->is_hashed = true;
4372 : 1058 : new_rollups = lappend(new_rollups, rollup);
4373 : : }
4374 : : }
4375 : :
4376 : : /*
4377 : : * If we didn't find anything nonempty to hash, then bail. We'll
4378 : : * generate a path from the is_sorted case.
4379 : : */
4380 [ - + ]: 438 : if (new_rollups == NIL)
3275 rhodiumtoad@postgres 4381 :UBC 0 : return;
4382 : :
4383 : : /*
4384 : : * If there were empty grouping sets they should have been in the
4385 : : * first rollup.
4386 : : */
3275 rhodiumtoad@postgres 4387 [ + + - + ]:CBC 438 : Assert(!unhashed_rollup || !empty_sets);
4388 : :
4389 [ + + ]: 438 : if (unhashed_rollup)
4390 : : {
4391 : 18 : new_rollups = lappend(new_rollups, unhashed_rollup);
4392 : 18 : strat = AGG_MIXED;
4393 : : }
4394 [ + + ]: 420 : else if (empty_sets)
4395 : : {
4396 : 247 : RollupData *rollup = makeNode(RollupData);
4397 : :
4398 : 247 : rollup->groupClause = NIL;
4399 : 247 : rollup->gsets_data = empty_sets_data;
4400 : 247 : rollup->gsets = empty_sets;
4401 : 247 : rollup->numGroups = list_length(empty_sets);
4402 : 247 : rollup->hashable = false;
4403 : 247 : rollup->is_hashed = false;
4404 : 247 : new_rollups = lappend(new_rollups, rollup);
4405 : 247 : strat = AGG_MIXED;
4406 : : }
4407 : :
4408 : 438 : add_path(grouped_rel, (Path *)
4409 : 438 : create_groupingsets_path(root,
4410 : : grouped_rel,
4411 : : path,
4412 : 438 : (List *) parse->havingQual,
4413 : : strat,
4414 : : new_rollups,
4415 : : agg_costs));
4416 : 438 : return;
4417 : : }
4418 : :
4419 : : /*
4420 : : * If we have sorted input but nothing we can do with it, bail.
4421 : : */
1306 tgl@sss.pgh.pa.us 4422 [ - + ]: 540 : if (gd->rollups == NIL)
3275 rhodiumtoad@postgres 4423 :UBC 0 : return;
4424 : :
4425 : : /*
4426 : : * Given sorted input, we try and make two paths: one sorted and one mixed
4427 : : * sort/hash. (We need to try both because hashagg might be disabled, or
4428 : : * some columns might not be sortable.)
4429 : : *
4430 : : * can_hash is passed in as false if some obstacle elsewhere (such as
4431 : : * ordered aggs) means that we shouldn't consider hashing at all.
4432 : : */
3275 rhodiumtoad@postgres 4433 [ + + + - ]:CBC 540 : if (can_hash && gd->any_hashable)
4434 : : {
4435 : 492 : List *rollups = NIL;
4436 : 492 : List *hash_sets = list_copy(gd->unsortable_sets);
1694 tgl@sss.pgh.pa.us 4437 : 492 : double availspace = hash_mem_limit;
4438 : : ListCell *lc;
4439 : :
4440 : : /*
4441 : : * Account first for space needed for groups we can't sort at all.
4442 : : */
1937 heikki.linnakangas@i 4443 : 492 : availspace -= estimate_hashagg_tablesize(root,
4444 : : path,
4445 : : agg_costs,
4446 : : gd->dNumHashGroups);
4447 : :
3275 rhodiumtoad@postgres 4448 [ + - + + ]: 492 : if (availspace > 0 && list_length(gd->rollups) > 1)
4449 : : {
4450 : : double scale;
4451 : 249 : int num_rollups = list_length(gd->rollups);
4452 : : int k_capacity;
4453 : 249 : int *k_weights = palloc(num_rollups * sizeof(int));
4454 : 249 : Bitmapset *hash_items = NULL;
4455 : : int i;
4456 : :
4457 : : /*
4458 : : * We treat this as a knapsack problem: the knapsack capacity
4459 : : * represents hash_mem, the item weights are the estimated memory
4460 : : * usage of the hashtables needed to implement a single rollup,
4461 : : * and we really ought to use the cost saving as the item value;
4462 : : * however, currently the costs assigned to sort nodes don't
4463 : : * reflect the comparison costs well, and so we treat all items as
4464 : : * of equal value (each rollup we hash instead saves us one sort).
4465 : : *
4466 : : * To use the discrete knapsack, we need to scale the values to a
4467 : : * reasonably small bounded range. We choose to allow a 5% error
4468 : : * margin; we have no more than 4096 rollups in the worst possible
4469 : : * case, which with a 5% error margin will require a bit over 42MB
4470 : : * of workspace. (Anyone wanting to plan queries that complex had
4471 : : * better have the memory for it. In more reasonable cases, with
4472 : : * no more than a couple of dozen rollups, the memory usage will
4473 : : * be negligible.)
4474 : : *
4475 : : * k_capacity is naturally bounded, but we clamp the values for
4476 : : * scale and weight (below) to avoid overflows or underflows (or
4477 : : * uselessly trying to use a scale factor less than 1 byte).
4478 : : */
4479 [ + - ]: 249 : scale = Max(availspace / (20.0 * num_rollups), 1.0);
4480 : 249 : k_capacity = (int) floor(availspace / scale);
4481 : :
4482 : : /*
4483 : : * We leave the first rollup out of consideration since it's the
4484 : : * one that matches the input sort order. We assign indexes "i"
4485 : : * to only those entries considered for hashing; the second loop,
4486 : : * below, must use the same condition.
4487 : : */
4488 : 249 : i = 0;
1994 tgl@sss.pgh.pa.us 4489 [ + - + + : 630 : for_each_from(lc, gd->rollups, 1)
+ + ]
4490 : : {
3113 4491 : 381 : RollupData *rollup = lfirst_node(RollupData, lc);
4492 : :
3275 rhodiumtoad@postgres 4493 [ + - ]: 381 : if (rollup->hashable)
4494 : : {
1937 heikki.linnakangas@i 4495 : 381 : double sz = estimate_hashagg_tablesize(root,
4496 : : path,
4497 : : agg_costs,
4498 : : rollup->numGroups);
4499 : :
4500 : : /*
4501 : : * If sz is enormous, but hash_mem (and hence scale) is
4502 : : * small, avoid integer overflow here.
4503 : : */
3275 rhodiumtoad@postgres 4504 [ + + ]: 381 : k_weights[i] = (int) Min(floor(sz / scale),
4505 : : k_capacity + 1.0);
4506 : 381 : ++i;
4507 : : }
4508 : : }
4509 : :
4510 : : /*
4511 : : * Apply knapsack algorithm; compute the set of items which
4512 : : * maximizes the value stored (in this case the number of sorts
4513 : : * saved) while keeping the total size (approximately) within
4514 : : * capacity.
4515 : : */
4516 [ + - ]: 249 : if (i > 0)
4517 : 249 : hash_items = DiscreteKnapsack(k_capacity, i, k_weights, NULL);
4518 : :
4519 [ + - ]: 249 : if (!bms_is_empty(hash_items))
4520 : : {
4521 : 249 : rollups = list_make1(linitial(gd->rollups));
4522 : :
4523 : 249 : i = 0;
1994 tgl@sss.pgh.pa.us 4524 [ + - + + : 630 : for_each_from(lc, gd->rollups, 1)
+ + ]
4525 : : {
3113 4526 : 381 : RollupData *rollup = lfirst_node(RollupData, lc);
4527 : :
3275 rhodiumtoad@postgres 4528 [ + - ]: 381 : if (rollup->hashable)
4529 : : {
4530 [ + + ]: 381 : if (bms_is_member(i, hash_items))
4531 : 363 : hash_sets = list_concat(hash_sets,
2407 tgl@sss.pgh.pa.us 4532 : 363 : rollup->gsets_data);
4533 : : else
3275 rhodiumtoad@postgres 4534 : 18 : rollups = lappend(rollups, rollup);
4535 : 381 : ++i;
4536 : : }
4537 : : else
3275 rhodiumtoad@postgres 4538 :UBC 0 : rollups = lappend(rollups, rollup);
4539 : : }
4540 : : }
4541 : : }
4542 : :
3275 rhodiumtoad@postgres 4543 [ + + + + ]:CBC 492 : if (!rollups && hash_sets)
4544 : 12 : rollups = list_copy(gd->rollups);
4545 : :
4546 [ + + + + : 925 : foreach(lc, hash_sets)
+ + ]
4547 : : {
3113 tgl@sss.pgh.pa.us 4548 : 433 : GroupingSetData *gs = lfirst_node(GroupingSetData, lc);
3275 rhodiumtoad@postgres 4549 : 433 : RollupData *rollup = makeNode(RollupData);
4550 : :
4551 [ - + ]: 433 : Assert(gs->set != NIL);
4552 : :
647 akorotkov@postgresql 4553 : 433 : rollup->groupClause = preprocess_groupclause(root, gs->set);
3275 rhodiumtoad@postgres 4554 : 433 : rollup->gsets_data = list_make1(gs);
4555 : 433 : rollup->gsets = remap_to_groupclause_idx(rollup->groupClause,
4556 : : rollup->gsets_data,
4557 : : gd->tleref_to_colnum_map);
4558 : 433 : rollup->numGroups = gs->numGroups;
4559 : 433 : rollup->hashable = true;
4560 : 433 : rollup->is_hashed = true;
4561 : 433 : rollups = lcons(rollup, rollups);
4562 : : }
4563 : :
4564 [ + + ]: 492 : if (rollups)
4565 : : {
4566 : 261 : add_path(grouped_rel, (Path *)
4567 : 261 : create_groupingsets_path(root,
4568 : : grouped_rel,
4569 : : path,
4570 : 261 : (List *) parse->havingQual,
4571 : : AGG_MIXED,
4572 : : rollups,
4573 : : agg_costs));
4574 : : }
4575 : : }
4576 : :
4577 : : /*
4578 : : * Now try the simple sorted case.
4579 : : */
4580 [ + + ]: 540 : if (!gd->unsortable_sets)
4581 : 525 : add_path(grouped_rel, (Path *)
4582 : 525 : create_groupingsets_path(root,
4583 : : grouped_rel,
4584 : : path,
4585 : 525 : (List *) parse->havingQual,
4586 : : AGG_SORTED,
4587 : : gd->rollups,
4588 : : agg_costs));
4589 : : }
4590 : :
4591 : : /*
4592 : : * create_window_paths
4593 : : *
4594 : : * Build a new upperrel containing Paths for window-function evaluation.
4595 : : *
4596 : : * input_rel: contains the source-data Paths
4597 : : * input_target: result of make_window_input_target
4598 : : * output_target: what the topmost WindowAggPath should return
4599 : : * wflists: result of find_window_functions
4600 : : * activeWindows: result of select_active_windows
4601 : : *
4602 : : * Note: all Paths in input_rel are expected to return input_target.
4603 : : */
4604 : : static RelOptInfo *
3660 tgl@sss.pgh.pa.us 4605 : 1338 : create_window_paths(PlannerInfo *root,
4606 : : RelOptInfo *input_rel,
4607 : : PathTarget *input_target,
4608 : : PathTarget *output_target,
4609 : : bool output_target_parallel_safe,
4610 : : WindowFuncLists *wflists,
4611 : : List *activeWindows)
4612 : : {
4613 : : RelOptInfo *window_rel;
4614 : : ListCell *lc;
4615 : :
4616 : : /* For now, do all work in the (WINDOW, NULL) upperrel */
4617 : 1338 : window_rel = fetch_upper_rel(root, UPPERREL_WINDOW, NULL);
4618 : :
4619 : : /*
4620 : : * If the input relation is not parallel-safe, then the window relation
4621 : : * can't be parallel-safe, either. Otherwise, we need to examine the
4622 : : * target list and active windows for non-parallel-safe constructs.
4623 : : */
2929 rhaas@postgresql.org 4624 [ + + - + : 1338 : if (input_rel->consider_parallel && output_target_parallel_safe &&
- - ]
3495 tgl@sss.pgh.pa.us 4625 :UBC 0 : is_parallel_safe(root, (Node *) activeWindows))
3544 rhaas@postgresql.org 4626 : 0 : window_rel->consider_parallel = true;
4627 : :
4628 : : /*
4629 : : * If the input rel belongs to a single FDW, so does the window rel.
4630 : : */
3544 tgl@sss.pgh.pa.us 4631 :CBC 1338 : window_rel->serverid = input_rel->serverid;
3530 4632 : 1338 : window_rel->userid = input_rel->userid;
4633 : 1338 : window_rel->useridiscurrent = input_rel->useridiscurrent;
3544 4634 : 1338 : window_rel->fdwroutine = input_rel->fdwroutine;
4635 : :
4636 : : /*
4637 : : * Consider computing window functions starting from the existing
4638 : : * cheapest-total path (which will likely require a sort) as well as any
4639 : : * existing paths that satisfy or partially satisfy root->window_pathkeys.
4640 : : */
3660 4641 [ + - + + : 2846 : foreach(lc, input_rel->pathlist)
+ + ]
4642 : : {
4643 : 1508 : Path *path = (Path *) lfirst(lc);
4644 : : int presorted_keys;
4645 : :
4646 [ + + + + ]: 1678 : if (path == input_rel->cheapest_total_path ||
2007 drowley@postgresql.o 4647 : 170 : pathkeys_count_contained_in(root->window_pathkeys, path->pathkeys,
4648 : 76 : &presorted_keys) ||
4649 [ + + ]: 76 : presorted_keys > 0)
3660 tgl@sss.pgh.pa.us 4650 : 1445 : create_one_window_path(root,
4651 : : window_rel,
4652 : : path,
4653 : : input_target,
4654 : : output_target,
4655 : : wflists,
4656 : : activeWindows);
4657 : : }
4658 : :
4659 : : /*
4660 : : * If there is an FDW that's responsible for all baserels of the query,
4661 : : * let it consider adding ForeignPaths.
4662 : : */
3544 4663 [ + + ]: 1338 : if (window_rel->fdwroutine &&
4664 [ + - ]: 6 : window_rel->fdwroutine->GetForeignUpperPaths)
4665 : 6 : window_rel->fdwroutine->GetForeignUpperPaths(root, UPPERREL_WINDOW,
4666 : : input_rel, window_rel,
4667 : : NULL);
4668 : :
4669 : : /* Let extensions possibly add some more paths */
3624 4670 [ - + ]: 1338 : if (create_upper_paths_hook)
3624 tgl@sss.pgh.pa.us 4671 :UBC 0 : (*create_upper_paths_hook) (root, UPPERREL_WINDOW,
4672 : : input_rel, window_rel, NULL);
4673 : :
4674 : : /* Now choose the best path(s) */
3660 tgl@sss.pgh.pa.us 4675 :CBC 1338 : set_cheapest(window_rel);
4676 : :
4677 : 1338 : return window_rel;
4678 : : }
4679 : :
4680 : : /*
4681 : : * Stack window-function implementation steps atop the given Path, and
4682 : : * add the result to window_rel.
4683 : : *
4684 : : * window_rel: upperrel to contain result
4685 : : * path: input Path to use (must return input_target)
4686 : : * input_target: result of make_window_input_target
4687 : : * output_target: what the topmost WindowAggPath should return
4688 : : * wflists: result of find_window_functions
4689 : : * activeWindows: result of select_active_windows
4690 : : */
4691 : : static void
4692 : 1445 : create_one_window_path(PlannerInfo *root,
4693 : : RelOptInfo *window_rel,
4694 : : Path *path,
4695 : : PathTarget *input_target,
4696 : : PathTarget *output_target,
4697 : : WindowFuncLists *wflists,
4698 : : List *activeWindows)
4699 : : {
4700 : : PathTarget *window_target;
4701 : : ListCell *l;
1437 drowley@postgresql.o 4702 : 1445 : List *topqual = NIL;
4703 : :
4704 : : /*
4705 : : * Since each window clause could require a different sort order, we stack
4706 : : * up a WindowAgg node for each clause, with sort steps between them as
4707 : : * needed. (We assume that select_active_windows chose a good order for
4708 : : * executing the clauses in.)
4709 : : *
4710 : : * input_target should contain all Vars and Aggs needed for the result.
4711 : : * (In some cases we wouldn't need to propagate all of these all the way
4712 : : * to the top, since they might only be needed as inputs to WindowFuncs.
4713 : : * It's probably not worth trying to optimize that though.) It must also
4714 : : * contain all window partitioning and sorting expressions, to ensure
4715 : : * they're computed only once at the bottom of the stack (that's critical
4716 : : * for volatile functions). As we climb up the stack, we'll add outputs
4717 : : * for the WindowFuncs computed at each level.
4718 : : */
3658 tgl@sss.pgh.pa.us 4719 : 1445 : window_target = input_target;
4720 : :
3660 4721 [ + - + + : 2983 : foreach(l, activeWindows)
+ + ]
4722 : : {
3113 4723 : 1538 : WindowClause *wc = lfirst_node(WindowClause, l);
4724 : : List *window_pathkeys;
679 drowley@postgresql.o 4725 : 1538 : List *runcondition = NIL;
4726 : : int presorted_keys;
4727 : : bool is_sorted;
4728 : : bool topwindow;
4729 : : ListCell *lc2;
4730 : :
3660 tgl@sss.pgh.pa.us 4731 : 1538 : window_pathkeys = make_pathkeys_for_window(root,
4732 : : wc,
4733 : : root->processed_tlist);
4734 : :
2007 drowley@postgresql.o 4735 : 1538 : is_sorted = pathkeys_count_contained_in(window_pathkeys,
4736 : : path->pathkeys,
4737 : : &presorted_keys);
4738 : :
4739 : : /* Sort if necessary */
4740 [ + + ]: 1538 : if (!is_sorted)
4741 : : {
4742 : : /*
4743 : : * No presorted keys or incremental sort disabled, just perform a
4744 : : * complete sort.
4745 : : */
4746 [ + + - + ]: 1092 : if (presorted_keys == 0 || !enable_incremental_sort)
4747 : 1061 : path = (Path *) create_sort_path(root, window_rel,
4748 : : path,
4749 : : window_pathkeys,
4750 : : -1.0);
4751 : : else
4752 : : {
4753 : : /*
4754 : : * Since we have presorted keys and incremental sort is
4755 : : * enabled, just use incremental sort.
4756 : : */
4757 : 31 : path = (Path *) create_incremental_sort_path(root,
4758 : : window_rel,
4759 : : path,
4760 : : window_pathkeys,
4761 : : presorted_keys,
4762 : : -1.0);
4763 : : }
4764 : : }
4765 : :
2435 tgl@sss.pgh.pa.us 4766 [ + + ]: 1538 : if (lnext(activeWindows, l))
4767 : : {
4768 : : /*
4769 : : * Add the current WindowFuncs to the output target for this
4770 : : * intermediate WindowAggPath. We must copy window_target to
4771 : : * avoid changing the previous path's target.
4772 : : *
4773 : : * Note: a WindowFunc adds nothing to the target's eval costs; but
4774 : : * we do need to account for the increase in tlist width.
4775 : : */
817 4776 : 93 : int64 tuple_width = window_target->width;
4777 : :
3658 4778 : 93 : window_target = copy_pathtarget(window_target);
4779 [ + - + + : 222 : foreach(lc2, wflists->windowFuncs[wc->winref])
+ + ]
4780 : : {
3261 4781 : 129 : WindowFunc *wfunc = lfirst_node(WindowFunc, lc2);
4782 : :
3658 4783 : 129 : add_column_to_pathtarget(window_target, (Expr *) wfunc, 0);
817 4784 : 129 : tuple_width += get_typavgwidth(wfunc->wintype, -1);
4785 : : }
4786 : 93 : window_target->width = clamp_width_est(tuple_width);
4787 : : }
4788 : : else
4789 : : {
4790 : : /* Install the goal target in the topmost WindowAgg */
3658 4791 : 1445 : window_target = output_target;
4792 : : }
4793 : :
4794 : : /* mark the final item in the list as the top-level window */
1437 drowley@postgresql.o 4795 : 1538 : topwindow = foreach_current_index(l) == list_length(activeWindows) - 1;
4796 : :
4797 : : /*
4798 : : * Collect the WindowFuncRunConditions from each WindowFunc and
4799 : : * convert them into OpExprs
4800 : : */
679 4801 [ + - + + : 3517 : foreach(lc2, wflists->windowFuncs[wc->winref])
+ + ]
4802 : : {
4803 : : ListCell *lc3;
4804 : 1979 : WindowFunc *wfunc = lfirst_node(WindowFunc, lc2);
4805 : :
4806 [ + + + + : 2069 : foreach(lc3, wfunc->runCondition)
+ + ]
4807 : : {
4808 : : WindowFuncRunCondition *wfuncrc =
4809 : 90 : lfirst_node(WindowFuncRunCondition, lc3);
4810 : : Expr *opexpr;
4811 : : Expr *leftop;
4812 : : Expr *rightop;
4813 : :
4814 [ + + ]: 90 : if (wfuncrc->wfunc_left)
4815 : : {
4816 : 81 : leftop = (Expr *) copyObject(wfunc);
4817 : 81 : rightop = copyObject(wfuncrc->arg);
4818 : : }
4819 : : else
4820 : : {
4821 : 9 : leftop = copyObject(wfuncrc->arg);
4822 : 9 : rightop = (Expr *) copyObject(wfunc);
4823 : : }
4824 : :
4825 : 90 : opexpr = make_opclause(wfuncrc->opno,
4826 : : BOOLOID,
4827 : : false,
4828 : : leftop,
4829 : : rightop,
4830 : : InvalidOid,
4831 : : wfuncrc->inputcollid);
4832 : :
4833 : 90 : runcondition = lappend(runcondition, opexpr);
4834 : :
4835 [ + + ]: 90 : if (!topwindow)
4836 : 12 : topqual = lappend(topqual, opexpr);
4837 : : }
4838 : : }
4839 : :
4840 : : path = (Path *)
3658 tgl@sss.pgh.pa.us 4841 [ + + ]: 1538 : create_windowagg_path(root, window_rel, path, window_target,
3660 4842 : 1538 : wflists->windowFuncs[wc->winref],
4843 : : runcondition, wc,
4844 : : topwindow ? topqual : NIL, topwindow);
4845 : : }
4846 : :
4847 : 1445 : add_path(window_rel, path);
7644 4848 : 1445 : }
4849 : :
4850 : : /*
4851 : : * create_distinct_paths
4852 : : *
4853 : : * Build a new upperrel containing Paths for SELECT DISTINCT evaluation.
4854 : : *
4855 : : * input_rel: contains the source-data Paths
4856 : : * target: the pathtarget for the result Paths to compute
4857 : : *
4858 : : * Note: input paths should already compute the desired pathtarget, since
4859 : : * Sort/Unique won't project anything.
4860 : : */
4861 : : static RelOptInfo *
767 drowley@postgresql.o 4862 : 1606 : create_distinct_paths(PlannerInfo *root, RelOptInfo *input_rel,
4863 : : PathTarget *target)
4864 : : {
4865 : : RelOptInfo *distinct_rel;
4866 : :
4867 : : /* For now, do all work in the (DISTINCT, NULL) upperrel */
3660 tgl@sss.pgh.pa.us 4868 : 1606 : distinct_rel = fetch_upper_rel(root, UPPERREL_DISTINCT, NULL);
4869 : :
4870 : : /*
4871 : : * We don't compute anything at this level, so distinct_rel will be
4872 : : * parallel-safe if the input rel is parallel-safe. In particular, if
4873 : : * there is a DISTINCT ON (...) clause, any path for the input_rel will
4874 : : * output those expressions, and will not be parallel-safe unless those
4875 : : * expressions are parallel-safe.
4876 : : */
3544 rhaas@postgresql.org 4877 : 1606 : distinct_rel->consider_parallel = input_rel->consider_parallel;
4878 : :
4879 : : /*
4880 : : * If the input rel belongs to a single FDW, so does the distinct_rel.
4881 : : */
tgl@sss.pgh.pa.us 4882 : 1606 : distinct_rel->serverid = input_rel->serverid;
3530 4883 : 1606 : distinct_rel->userid = input_rel->userid;
4884 : 1606 : distinct_rel->useridiscurrent = input_rel->useridiscurrent;
3544 4885 : 1606 : distinct_rel->fdwroutine = input_rel->fdwroutine;
4886 : :
4887 : : /* build distinct paths based on input_rel's pathlist */
1666 drowley@postgresql.o 4888 : 1606 : create_final_distinct_paths(root, input_rel, distinct_rel);
4889 : :
4890 : : /* now build distinct paths based on input_rel's partial_pathlist */
767 4891 : 1606 : create_partial_distinct_paths(root, input_rel, distinct_rel, target);
4892 : :
4893 : : /* Give a helpful error if we failed to create any paths */
1666 4894 [ - + ]: 1606 : if (distinct_rel->pathlist == NIL)
1666 drowley@postgresql.o 4895 [ # # ]:UBC 0 : ereport(ERROR,
4896 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4897 : : errmsg("could not implement DISTINCT"),
4898 : : errdetail("Some of the datatypes only support hashing, while others only support sorting.")));
4899 : :
4900 : : /*
4901 : : * If there is an FDW that's responsible for all baserels of the query,
4902 : : * let it consider adding ForeignPaths.
4903 : : */
1666 drowley@postgresql.o 4904 [ + + ]:CBC 1606 : if (distinct_rel->fdwroutine &&
4905 [ + - ]: 8 : distinct_rel->fdwroutine->GetForeignUpperPaths)
4906 : 8 : distinct_rel->fdwroutine->GetForeignUpperPaths(root,
4907 : : UPPERREL_DISTINCT,
4908 : : input_rel,
4909 : : distinct_rel,
4910 : : NULL);
4911 : :
4912 : : /* Let extensions possibly add some more paths */
4913 [ - + ]: 1606 : if (create_upper_paths_hook)
1666 drowley@postgresql.o 4914 :UBC 0 : (*create_upper_paths_hook) (root, UPPERREL_DISTINCT, input_rel,
4915 : : distinct_rel, NULL);
4916 : :
4917 : : /* Now choose the best path(s) */
1666 drowley@postgresql.o 4918 :CBC 1606 : set_cheapest(distinct_rel);
4919 : :
4920 : 1606 : return distinct_rel;
4921 : : }
4922 : :
4923 : : /*
4924 : : * create_partial_distinct_paths
4925 : : *
4926 : : * Process 'input_rel' partial paths and add unique/aggregate paths to the
4927 : : * UPPERREL_PARTIAL_DISTINCT rel. For paths created, add Gather/GatherMerge
4928 : : * paths on top and add a final unique/aggregate path to remove any duplicate
4929 : : * produced from combining rows from parallel workers.
4930 : : */
4931 : : static void
4932 : 1606 : create_partial_distinct_paths(PlannerInfo *root, RelOptInfo *input_rel,
4933 : : RelOptInfo *final_distinct_rel,
4934 : : PathTarget *target)
4935 : : {
4936 : : RelOptInfo *partial_distinct_rel;
4937 : : Query *parse;
4938 : : List *distinctExprs;
4939 : : double numDistinctRows;
4940 : : Path *cheapest_partial_path;
4941 : : ListCell *lc;
4942 : :
4943 : : /* nothing to do when there are no partial paths in the input rel */
4944 [ + + + + ]: 1606 : if (!input_rel->consider_parallel || input_rel->partial_pathlist == NIL)
4945 : 1552 : return;
4946 : :
4947 : 54 : parse = root->parse;
4948 : :
4949 : : /* can't do parallel DISTINCT ON */
4950 [ - + ]: 54 : if (parse->hasDistinctOn)
1666 drowley@postgresql.o 4951 :UBC 0 : return;
4952 : :
1666 drowley@postgresql.o 4953 :CBC 54 : partial_distinct_rel = fetch_upper_rel(root, UPPERREL_PARTIAL_DISTINCT,
4954 : : NULL);
767 4955 : 54 : partial_distinct_rel->reltarget = target;
1666 4956 : 54 : partial_distinct_rel->consider_parallel = input_rel->consider_parallel;
4957 : :
4958 : : /*
4959 : : * If input_rel belongs to a single FDW, so does the partial_distinct_rel.
4960 : : */
4961 : 54 : partial_distinct_rel->serverid = input_rel->serverid;
4962 : 54 : partial_distinct_rel->userid = input_rel->userid;
4963 : 54 : partial_distinct_rel->useridiscurrent = input_rel->useridiscurrent;
4964 : 54 : partial_distinct_rel->fdwroutine = input_rel->fdwroutine;
4965 : :
4966 : 54 : cheapest_partial_path = linitial(input_rel->partial_pathlist);
4967 : :
1152 tgl@sss.pgh.pa.us 4968 : 54 : distinctExprs = get_sortgrouplist_exprs(root->processed_distinctClause,
4969 : : parse->targetList);
4970 : :
4971 : : /* estimate how many distinct rows we'll get from each worker */
1666 drowley@postgresql.o 4972 : 54 : numDistinctRows = estimate_num_groups(root, distinctExprs,
4973 : : cheapest_partial_path->rows,
4974 : : NULL, NULL);
4975 : :
4976 : : /*
4977 : : * Try sorting the cheapest path and incrementally sorting any paths with
4978 : : * presorted keys and put a unique paths atop of those. We'll also
4979 : : * attempt to reorder the required pathkeys to match the input path's
4980 : : * pathkeys as much as possible, in hopes of avoiding a possible need to
4981 : : * re-sort.
4982 : : */
1152 tgl@sss.pgh.pa.us 4983 [ + - ]: 54 : if (grouping_is_sortable(root->processed_distinctClause))
4984 : : {
1666 drowley@postgresql.o 4985 [ + - + + : 117 : foreach(lc, input_rel->partial_pathlist)
+ + ]
4986 : : {
1159 4987 : 63 : Path *input_path = (Path *) lfirst(lc);
4988 : : Path *sorted_path;
474 rguo@postgresql.org 4989 : 63 : List *useful_pathkeys_list = NIL;
4990 : :
4991 : : useful_pathkeys_list =
4992 : 63 : get_useful_pathkeys_for_distinct(root,
4993 : : root->distinct_pathkeys,
4994 : : input_path->pathkeys);
4995 [ - + ]: 63 : Assert(list_length(useful_pathkeys_list) > 0);
4996 : :
4997 [ + - + + : 195 : foreach_node(List, useful_pathkeys, useful_pathkeys_list)
+ + ]
4998 : : {
4999 : 69 : sorted_path = make_ordered_path(root,
5000 : : partial_distinct_rel,
5001 : : input_path,
5002 : : cheapest_partial_path,
5003 : : useful_pathkeys,
5004 : : -1.0);
5005 : :
5006 [ + + ]: 69 : if (sorted_path == NULL)
1159 drowley@postgresql.o 5007 : 6 : continue;
5008 : :
5009 : : /*
5010 : : * An empty distinct_pathkeys means all tuples have the same
5011 : : * value for the DISTINCT clause. See
5012 : : * create_final_distinct_paths()
5013 : : */
474 rguo@postgresql.org 5014 [ + + ]: 63 : if (root->distinct_pathkeys == NIL)
5015 : : {
5016 : : Node *limitCount;
5017 : :
5018 : 3 : limitCount = (Node *) makeConst(INT8OID, -1, InvalidOid,
5019 : : sizeof(int64),
5020 : : Int64GetDatum(1), false,
5021 : : true);
5022 : :
5023 : : /*
5024 : : * Apply a LimitPath onto the partial path to restrict the
5025 : : * tuples from each worker to 1.
5026 : : * create_final_distinct_paths will need to apply an
5027 : : * additional LimitPath to restrict this to a single row
5028 : : * after the Gather node. If the query already has a
5029 : : * LIMIT clause, then we could end up with three Limit
5030 : : * nodes in the final plan. Consolidating the top two of
5031 : : * these could be done, but does not seem worth troubling
5032 : : * over.
5033 : : */
5034 : 3 : add_partial_path(partial_distinct_rel, (Path *)
5035 : 3 : create_limit_path(root, partial_distinct_rel,
5036 : : sorted_path,
5037 : : NULL,
5038 : : limitCount,
5039 : : LIMIT_OPTION_COUNT,
5040 : : 0, 1));
5041 : : }
5042 : : else
5043 : : {
5044 : 60 : add_partial_path(partial_distinct_rel, (Path *)
208 rguo@postgresql.org 5045 :GNC 60 : create_unique_path(root, partial_distinct_rel,
5046 : : sorted_path,
5047 : 60 : list_length(root->distinct_pathkeys),
5048 : : numDistinctRows));
5049 : : }
5050 : : }
5051 : : }
5052 : : }
5053 : :
5054 : : /*
5055 : : * Now try hash aggregate paths, if enabled and hashing is possible. Since
5056 : : * we're not on the hook to ensure we do our best to create at least one
5057 : : * path here, we treat enable_hashagg as a hard off-switch rather than the
5058 : : * slightly softer variant in create_final_distinct_paths.
5059 : : */
1152 tgl@sss.pgh.pa.us 5060 [ + + + - ]:CBC 54 : if (enable_hashagg && grouping_is_hashable(root->processed_distinctClause))
5061 : : {
1666 drowley@postgresql.o 5062 : 39 : add_partial_path(partial_distinct_rel, (Path *)
5063 : 39 : create_agg_path(root,
5064 : : partial_distinct_rel,
5065 : : cheapest_partial_path,
5066 : : cheapest_partial_path->pathtarget,
5067 : : AGG_HASHED,
5068 : : AGGSPLIT_SIMPLE,
5069 : : root->processed_distinctClause,
5070 : : NIL,
5071 : : NULL,
5072 : : numDistinctRows));
5073 : : }
5074 : :
5075 : : /*
5076 : : * If there is an FDW that's responsible for all baserels of the query,
5077 : : * let it consider adding ForeignPaths.
5078 : : */
5079 [ - + ]: 54 : if (partial_distinct_rel->fdwroutine &&
1666 drowley@postgresql.o 5080 [ # # ]:UBC 0 : partial_distinct_rel->fdwroutine->GetForeignUpperPaths)
5081 : 0 : partial_distinct_rel->fdwroutine->GetForeignUpperPaths(root,
5082 : : UPPERREL_PARTIAL_DISTINCT,
5083 : : input_rel,
5084 : : partial_distinct_rel,
5085 : : NULL);
5086 : :
5087 : : /* Let extensions possibly add some more partial paths */
1666 drowley@postgresql.o 5088 [ - + ]:CBC 54 : if (create_upper_paths_hook)
1666 drowley@postgresql.o 5089 :UBC 0 : (*create_upper_paths_hook) (root, UPPERREL_PARTIAL_DISTINCT,
5090 : : input_rel, partial_distinct_rel, NULL);
5091 : :
1666 drowley@postgresql.o 5092 [ + - ]:CBC 54 : if (partial_distinct_rel->partial_pathlist != NIL)
5093 : : {
771 5094 : 54 : generate_useful_gather_paths(root, partial_distinct_rel, true);
1666 5095 : 54 : set_cheapest(partial_distinct_rel);
5096 : :
5097 : : /*
5098 : : * Finally, create paths to distinctify the final result. This step
5099 : : * is needed to remove any duplicates due to combining rows from
5100 : : * parallel workers.
5101 : : */
5102 : 54 : create_final_distinct_paths(root, partial_distinct_rel,
5103 : : final_distinct_rel);
5104 : : }
5105 : : }
5106 : :
5107 : : /*
5108 : : * create_final_distinct_paths
5109 : : * Create distinct paths in 'distinct_rel' based on 'input_rel' pathlist
5110 : : *
5111 : : * input_rel: contains the source-data paths
5112 : : * distinct_rel: destination relation for storing created paths
5113 : : */
5114 : : static RelOptInfo *
5115 : 1660 : create_final_distinct_paths(PlannerInfo *root, RelOptInfo *input_rel,
5116 : : RelOptInfo *distinct_rel)
5117 : : {
5118 : 1660 : Query *parse = root->parse;
5119 : 1660 : Path *cheapest_input_path = input_rel->cheapest_total_path;
5120 : : double numDistinctRows;
5121 : : bool allow_hash;
5122 : :
5123 : : /* Estimate number of distinct rows there will be */
3660 tgl@sss.pgh.pa.us 5124 [ + + + - : 1660 : if (parse->groupClause || parse->groupingSets || parse->hasAggs ||
+ + ]
5125 [ - + ]: 1623 : root->hasHavingQual)
5126 : : {
5127 : : /*
5128 : : * If there was grouping or aggregation, use the number of input rows
5129 : : * as the estimated number of DISTINCT rows (ie, assume the input is
5130 : : * already mostly unique).
5131 : : */
5132 : 37 : numDistinctRows = cheapest_input_path->rows;
5133 : : }
5134 : : else
5135 : : {
5136 : : /*
5137 : : * Otherwise, the UNIQUE filter has effects comparable to GROUP BY.
5138 : : */
5139 : : List *distinctExprs;
5140 : :
1152 5141 : 1623 : distinctExprs = get_sortgrouplist_exprs(root->processed_distinctClause,
5142 : : parse->targetList);
3660 5143 : 1623 : numDistinctRows = estimate_num_groups(root, distinctExprs,
5144 : : cheapest_input_path->rows,
5145 : : NULL, NULL);
5146 : : }
5147 : :
5148 : : /*
5149 : : * Consider sort-based implementations of DISTINCT, if possible.
5150 : : */
1152 5151 [ + + ]: 1660 : if (grouping_is_sortable(root->processed_distinctClause))
5152 : : {
5153 : : /*
5154 : : * Firstly, if we have any adequately-presorted paths, just stick a
5155 : : * Unique node on those. We also, consider doing an explicit sort of
5156 : : * the cheapest input path and Unique'ing that. If any paths have
5157 : : * presorted keys then we'll create an incremental sort atop of those
5158 : : * before adding a unique node on the top. We'll also attempt to
5159 : : * reorder the required pathkeys to match the input path's pathkeys as
5160 : : * much as possible, in hopes of avoiding a possible need to re-sort.
5161 : : *
5162 : : * When we have DISTINCT ON, we must sort by the more rigorous of
5163 : : * DISTINCT and ORDER BY, else it won't have the desired behavior.
5164 : : * Also, if we do have to do an explicit sort, we might as well use
5165 : : * the more rigorous ordering to avoid a second sort later. (Note
5166 : : * that the parser will have ensured that one clause is a prefix of
5167 : : * the other.)
5168 : : */
5169 : : List *needed_pathkeys;
5170 : : ListCell *lc;
1159 drowley@postgresql.o 5171 [ + + ]: 1657 : double limittuples = root->distinct_pathkeys == NIL ? 1.0 : -1.0;
5172 : :
3660 tgl@sss.pgh.pa.us 5173 [ + + + + ]: 1781 : if (parse->hasDistinctOn &&
5174 : 124 : list_length(root->distinct_pathkeys) <
5175 : 124 : list_length(root->sort_pathkeys))
5176 : 27 : needed_pathkeys = root->sort_pathkeys;
5177 : : else
5178 : 1630 : needed_pathkeys = root->distinct_pathkeys;
5179 : :
5180 [ + - + + : 4495 : foreach(lc, input_rel->pathlist)
+ + ]
5181 : : {
1159 drowley@postgresql.o 5182 : 2838 : Path *input_path = (Path *) lfirst(lc);
5183 : : Path *sorted_path;
474 rguo@postgresql.org 5184 : 2838 : List *useful_pathkeys_list = NIL;
5185 : :
5186 : : useful_pathkeys_list =
5187 : 2838 : get_useful_pathkeys_for_distinct(root,
5188 : : needed_pathkeys,
5189 : : input_path->pathkeys);
5190 [ - + ]: 2838 : Assert(list_length(useful_pathkeys_list) > 0);
5191 : :
5192 [ + - + + : 8934 : foreach_node(List, useful_pathkeys, useful_pathkeys_list)
+ + ]
5193 : : {
5194 : 3258 : sorted_path = make_ordered_path(root,
5195 : : distinct_rel,
5196 : : input_path,
5197 : : cheapest_input_path,
5198 : : useful_pathkeys,
5199 : : limittuples);
5200 : :
5201 [ + + ]: 3258 : if (sorted_path == NULL)
1159 drowley@postgresql.o 5202 : 449 : continue;
5203 : :
5204 : : /*
5205 : : * distinct_pathkeys may have become empty if all of the
5206 : : * pathkeys were determined to be redundant. If all of the
5207 : : * pathkeys are redundant then each DISTINCT target must only
5208 : : * allow a single value, therefore all resulting tuples must
5209 : : * be identical (or at least indistinguishable by an equality
5210 : : * check). We can uniquify these tuples simply by just taking
5211 : : * the first tuple. All we do here is add a path to do "LIMIT
5212 : : * 1" atop of 'sorted_path'. When doing a DISTINCT ON we may
5213 : : * still have a non-NIL sort_pathkeys list, so we must still
5214 : : * only do this with paths which are correctly sorted by
5215 : : * sort_pathkeys.
5216 : : */
474 rguo@postgresql.org 5217 [ + + ]: 2809 : if (root->distinct_pathkeys == NIL)
5218 : : {
5219 : : Node *limitCount;
5220 : :
5221 : 69 : limitCount = (Node *) makeConst(INT8OID, -1, InvalidOid,
5222 : : sizeof(int64),
5223 : : Int64GetDatum(1), false,
5224 : : true);
5225 : :
5226 : : /*
5227 : : * If the query already has a LIMIT clause, then we could
5228 : : * end up with a duplicate LimitPath in the final plan.
5229 : : * That does not seem worth troubling over too much.
5230 : : */
5231 : 69 : add_path(distinct_rel, (Path *)
5232 : 69 : create_limit_path(root, distinct_rel, sorted_path,
5233 : : NULL, limitCount,
5234 : : LIMIT_OPTION_COUNT, 0, 1));
5235 : : }
5236 : : else
5237 : : {
5238 : 2740 : add_path(distinct_rel, (Path *)
208 rguo@postgresql.org 5239 :GNC 2740 : create_unique_path(root, distinct_rel,
5240 : : sorted_path,
5241 : 2740 : list_length(root->distinct_pathkeys),
5242 : : numDistinctRows));
5243 : : }
5244 : : }
5245 : : }
5246 : : }
5247 : :
5248 : : /*
5249 : : * Consider hash-based implementations of DISTINCT, if possible.
5250 : : *
5251 : : * If we were not able to make any other types of path, we *must* hash or
5252 : : * die trying. If we do have other choices, there are two things that
5253 : : * should prevent selection of hashing: if the query uses DISTINCT ON
5254 : : * (because it won't really have the expected behavior if we hash), or if
5255 : : * enable_hashagg is off.
5256 : : *
5257 : : * Note: grouping_is_hashable() is much more expensive to check than the
5258 : : * other gating conditions, so we want to do it last.
5259 : : */
3660 tgl@sss.pgh.pa.us 5260 [ + + ]:CBC 1660 : if (distinct_rel->pathlist == NIL)
5261 : 3 : allow_hash = true; /* we have no alternatives */
5262 [ + + + + ]: 1657 : else if (parse->hasDistinctOn || !enable_hashagg)
5263 : 199 : allow_hash = false; /* policy-based decision not to hash */
5264 : : else
2057 pg@bowt.ie 5265 : 1458 : allow_hash = true; /* default */
5266 : :
1152 tgl@sss.pgh.pa.us 5267 [ + + + - ]: 1660 : if (allow_hash && grouping_is_hashable(root->processed_distinctClause))
5268 : : {
5269 : : /* Generate hashed aggregate path --- no sort needed */
3660 5270 : 1461 : add_path(distinct_rel, (Path *)
5271 : 1461 : create_agg_path(root,
5272 : : distinct_rel,
5273 : : cheapest_input_path,
5274 : : cheapest_input_path->pathtarget,
5275 : : AGG_HASHED,
5276 : : AGGSPLIT_SIMPLE,
5277 : : root->processed_distinctClause,
5278 : : NIL,
5279 : : NULL,
5280 : : numDistinctRows));
5281 : : }
5282 : :
5283 : 1660 : return distinct_rel;
5284 : : }
5285 : :
5286 : : /*
5287 : : * get_useful_pathkeys_for_distinct
5288 : : * Get useful orderings of pathkeys for distinctClause by reordering
5289 : : * 'needed_pathkeys' to match the given 'path_pathkeys' as much as possible.
5290 : : *
5291 : : * This returns a list of pathkeys that can be useful for DISTINCT or DISTINCT
5292 : : * ON clause. For convenience, it always includes the given 'needed_pathkeys'.
5293 : : */
5294 : : static List *
474 rguo@postgresql.org 5295 : 2901 : get_useful_pathkeys_for_distinct(PlannerInfo *root, List *needed_pathkeys,
5296 : : List *path_pathkeys)
5297 : : {
5298 : 2901 : List *useful_pathkeys_list = NIL;
5299 : 2901 : List *useful_pathkeys = NIL;
5300 : :
5301 : : /* always include the given 'needed_pathkeys' */
5302 : 2901 : useful_pathkeys_list = lappend(useful_pathkeys_list,
5303 : : needed_pathkeys);
5304 : :
5305 [ - + ]: 2901 : if (!enable_distinct_reordering)
474 rguo@postgresql.org 5306 :UBC 0 : return useful_pathkeys_list;
5307 : :
5308 : : /*
5309 : : * Scan the given 'path_pathkeys' and construct a list of PathKey nodes
5310 : : * that match 'needed_pathkeys', but only up to the longest matching
5311 : : * prefix.
5312 : : *
5313 : : * When we have DISTINCT ON, we must ensure that the resulting pathkey
5314 : : * list matches initial distinctClause pathkeys; otherwise, it won't have
5315 : : * the desired behavior.
5316 : : */
474 rguo@postgresql.org 5317 [ + + + + :CBC 7185 : foreach_node(PathKey, pathkey, path_pathkeys)
+ + ]
5318 : : {
5319 : : /*
5320 : : * The PathKey nodes are canonical, so they can be checked for
5321 : : * equality by simple pointer comparison.
5322 : : */
5323 [ + + ]: 1397 : if (!list_member_ptr(needed_pathkeys, pathkey))
5324 : 5 : break;
5325 [ + + ]: 1392 : if (root->parse->hasDistinctOn &&
5326 [ + + ]: 100 : !list_member_ptr(root->distinct_pathkeys, pathkey))
5327 : 9 : break;
5328 : :
5329 : 1383 : useful_pathkeys = lappend(useful_pathkeys, pathkey);
5330 : : }
5331 : :
5332 : : /* If no match at all, no point in reordering needed_pathkeys */
5333 [ + + ]: 2901 : if (useful_pathkeys == NIL)
5334 : 1650 : return useful_pathkeys_list;
5335 : :
5336 : : /*
5337 : : * If not full match, the resulting pathkey list is not useful without
5338 : : * incremental sort.
5339 : : */
5340 [ + + ]: 1251 : if (list_length(useful_pathkeys) < list_length(needed_pathkeys) &&
5341 [ + + ]: 800 : !enable_incremental_sort)
5342 : 30 : return useful_pathkeys_list;
5343 : :
5344 : : /* Append the remaining PathKey nodes in needed_pathkeys */
5345 : 1221 : useful_pathkeys = list_concat_unique_ptr(useful_pathkeys,
5346 : : needed_pathkeys);
5347 : :
5348 : : /*
5349 : : * If the resulting pathkey list is the same as the 'needed_pathkeys',
5350 : : * just drop it.
5351 : : */
5352 [ + + ]: 1221 : if (compare_pathkeys(needed_pathkeys,
5353 : : useful_pathkeys) == PATHKEYS_EQUAL)
5354 : 795 : return useful_pathkeys_list;
5355 : :
5356 : 426 : useful_pathkeys_list = lappend(useful_pathkeys_list,
5357 : : useful_pathkeys);
5358 : :
5359 : 426 : return useful_pathkeys_list;
5360 : : }
5361 : :
5362 : : /*
5363 : : * create_ordered_paths
5364 : : *
5365 : : * Build a new upperrel containing Paths for ORDER BY evaluation.
5366 : : *
5367 : : * All paths in the result must satisfy the ORDER BY ordering.
5368 : : * The only new paths we need consider are an explicit full sort
5369 : : * and incremental sort on the cheapest-total existing path.
5370 : : *
5371 : : * input_rel: contains the source-data Paths
5372 : : * target: the output tlist the result Paths must emit
5373 : : * limit_tuples: estimated bound on the number of output tuples,
5374 : : * or -1 if no LIMIT or couldn't estimate
5375 : : *
5376 : : * XXX This only looks at sort_pathkeys. I wonder if it needs to look at the
5377 : : * other pathkeys (grouping, ...) like generate_useful_gather_paths.
5378 : : */
5379 : : static RelOptInfo *
3660 tgl@sss.pgh.pa.us 5380 : 41423 : create_ordered_paths(PlannerInfo *root,
5381 : : RelOptInfo *input_rel,
5382 : : PathTarget *target,
5383 : : bool target_parallel_safe,
5384 : : double limit_tuples)
5385 : : {
5386 : 41423 : Path *cheapest_input_path = input_rel->cheapest_total_path;
5387 : : RelOptInfo *ordered_rel;
5388 : : ListCell *lc;
5389 : :
5390 : : /* For now, do all work in the (ORDERED, NULL) upperrel */
5391 : 41423 : ordered_rel = fetch_upper_rel(root, UPPERREL_ORDERED, NULL);
5392 : :
5393 : : /*
5394 : : * If the input relation is not parallel-safe, then the ordered relation
5395 : : * can't be parallel-safe, either. Otherwise, it's parallel-safe if the
5396 : : * target list is parallel-safe.
5397 : : */
2929 rhaas@postgresql.org 5398 [ + + + + ]: 41423 : if (input_rel->consider_parallel && target_parallel_safe)
3544 5399 : 29069 : ordered_rel->consider_parallel = true;
5400 : :
5401 : : /* Assume that the same path generation strategies are allowed. */
46 rhaas@postgresql.org 5402 :GNC 41423 : ordered_rel->pgs_mask = input_rel->pgs_mask;
5403 : :
5404 : : /*
5405 : : * If the input rel belongs to a single FDW, so does the ordered_rel.
5406 : : */
3544 tgl@sss.pgh.pa.us 5407 :CBC 41423 : ordered_rel->serverid = input_rel->serverid;
3530 5408 : 41423 : ordered_rel->userid = input_rel->userid;
5409 : 41423 : ordered_rel->useridiscurrent = input_rel->useridiscurrent;
3544 5410 : 41423 : ordered_rel->fdwroutine = input_rel->fdwroutine;
5411 : :
3660 5412 [ + - + + : 105359 : foreach(lc, input_rel->pathlist)
+ + ]
5413 : : {
2169 tomas.vondra@postgre 5414 : 63936 : Path *input_path = (Path *) lfirst(lc);
5415 : : Path *sorted_path;
5416 : : bool is_sorted;
5417 : : int presorted_keys;
5418 : :
5419 : 63936 : is_sorted = pathkeys_count_contained_in(root->sort_pathkeys,
5420 : : input_path->pathkeys, &presorted_keys);
5421 : :
5422 [ + + ]: 63936 : if (is_sorted)
1185 drowley@postgresql.o 5423 : 24479 : sorted_path = input_path;
5424 : : else
5425 : : {
5426 : : /*
5427 : : * Try at least sorting the cheapest path and also try
5428 : : * incrementally sorting any path which is partially sorted
5429 : : * already (no need to deal with paths which have presorted keys
5430 : : * when incremental sort is disabled unless it's the cheapest
5431 : : * input path).
5432 : : */
5433 [ + + ]: 39457 : if (input_path != cheapest_input_path &&
5434 [ + + + + ]: 3442 : (presorted_keys == 0 || !enable_incremental_sort))
5435 : 1116 : continue;
5436 : :
5437 : : /*
5438 : : * We've no need to consider both a sort and incremental sort.
5439 : : * We'll just do a sort if there are no presorted keys and an
5440 : : * incremental sort when there are presorted keys.
5441 : : */
5442 [ + + + + ]: 38341 : if (presorted_keys == 0 || !enable_incremental_sort)
2169 tomas.vondra@postgre 5443 : 35674 : sorted_path = (Path *) create_sort_path(root,
5444 : : ordered_rel,
5445 : : input_path,
5446 : : root->sort_pathkeys,
5447 : : limit_tuples);
5448 : : else
1185 drowley@postgresql.o 5449 : 2667 : sorted_path = (Path *) create_incremental_sort_path(root,
5450 : : ordered_rel,
5451 : : input_path,
5452 : : root->sort_pathkeys,
5453 : : presorted_keys,
5454 : : limit_tuples);
5455 : : }
5456 : :
5457 : : /*
5458 : : * If the pathtarget of the result path has different expressions from
5459 : : * the target to be applied, a projection step is needed.
5460 : : */
557 rguo@postgresql.org 5461 [ + + ]: 62820 : if (!equal(sorted_path->pathtarget->exprs, target->exprs))
1185 drowley@postgresql.o 5462 : 197 : sorted_path = apply_projection_to_path(root, ordered_rel,
5463 : : sorted_path, target);
5464 : :
5465 : 62820 : add_path(ordered_rel, sorted_path);
5466 : : }
5467 : :
5468 : : /*
5469 : : * generate_gather_paths() will have already generated a simple Gather
5470 : : * path for the best parallel path, if any, and the loop above will have
5471 : : * considered sorting it. Similarly, generate_gather_paths() will also
5472 : : * have generated order-preserving Gather Merge plans which can be used
5473 : : * without sorting if they happen to match the sort_pathkeys, and the loop
5474 : : * above will have handled those as well. However, there's one more
5475 : : * possibility: it may make sense to sort the cheapest partial path or
5476 : : * incrementally sort any partial path that is partially sorted according
5477 : : * to the required output order and then use Gather Merge.
5478 : : */
3293 rhaas@postgresql.org 5479 [ + + + + ]: 41423 : if (ordered_rel->consider_parallel && root->sort_pathkeys != NIL &&
5480 [ + + ]: 28967 : input_rel->partial_pathlist != NIL)
5481 : : {
5482 : : Path *cheapest_partial_path;
5483 : :
5484 : 1525 : cheapest_partial_path = linitial(input_rel->partial_pathlist);
5485 : :
774 drowley@postgresql.o 5486 [ + - + + : 3466 : foreach(lc, input_rel->partial_pathlist)
+ + ]
5487 : : {
5488 : 1941 : Path *input_path = (Path *) lfirst(lc);
5489 : : Path *sorted_path;
5490 : : bool is_sorted;
5491 : : int presorted_keys;
5492 : : double total_groups;
5493 : :
5494 : 1941 : is_sorted = pathkeys_count_contained_in(root->sort_pathkeys,
5495 : : input_path->pathkeys,
5496 : : &presorted_keys);
5497 : :
5498 [ + + ]: 1941 : if (is_sorted)
5499 : 353 : continue;
5500 : :
5501 : : /*
5502 : : * Try at least sorting the cheapest path and also try
5503 : : * incrementally sorting any path which is partially sorted
5504 : : * already (no need to deal with paths which have presorted keys
5505 : : * when incremental sort is disabled unless it's the cheapest
5506 : : * partial path).
5507 : : */
5508 [ + + ]: 1588 : if (input_path != cheapest_partial_path &&
5509 [ + - - + ]: 75 : (presorted_keys == 0 || !enable_incremental_sort))
774 drowley@postgresql.o 5510 :UBC 0 : continue;
5511 : :
5512 : : /*
5513 : : * We've no need to consider both a sort and incremental sort.
5514 : : * We'll just do a sort if there are no presorted keys and an
5515 : : * incremental sort when there are presorted keys.
5516 : : */
774 drowley@postgresql.o 5517 [ + + + + ]:CBC 1588 : if (presorted_keys == 0 || !enable_incremental_sort)
5518 : 1504 : sorted_path = (Path *) create_sort_path(root,
5519 : : ordered_rel,
5520 : : input_path,
5521 : : root->sort_pathkeys,
5522 : : limit_tuples);
5523 : : else
2168 tomas.vondra@postgre 5524 : 84 : sorted_path = (Path *) create_incremental_sort_path(root,
5525 : : ordered_rel,
5526 : : input_path,
5527 : : root->sort_pathkeys,
5528 : : presorted_keys,
5529 : : limit_tuples);
600 rguo@postgresql.org 5530 : 1588 : total_groups = compute_gather_rows(sorted_path);
5531 : : sorted_path = (Path *)
774 drowley@postgresql.o 5532 : 1588 : create_gather_merge_path(root, ordered_rel,
5533 : : sorted_path,
5534 : : sorted_path->pathtarget,
5535 : : root->sort_pathkeys, NULL,
5536 : : &total_groups);
5537 : :
5538 : : /*
5539 : : * If the pathtarget of the result path has different expressions
5540 : : * from the target to be applied, a projection step is needed.
5541 : : */
557 rguo@postgresql.org 5542 [ + + ]: 1588 : if (!equal(sorted_path->pathtarget->exprs, target->exprs))
774 drowley@postgresql.o 5543 : 3 : sorted_path = apply_projection_to_path(root, ordered_rel,
5544 : : sorted_path, target);
5545 : :
5546 : 1588 : add_path(ordered_rel, sorted_path);
5547 : : }
5548 : : }
5549 : :
5550 : : /*
5551 : : * If there is an FDW that's responsible for all baserels of the query,
5552 : : * let it consider adding ForeignPaths.
5553 : : */
3544 tgl@sss.pgh.pa.us 5554 [ + + ]: 41423 : if (ordered_rel->fdwroutine &&
5555 [ + + ]: 193 : ordered_rel->fdwroutine->GetForeignUpperPaths)
5556 : 185 : ordered_rel->fdwroutine->GetForeignUpperPaths(root, UPPERREL_ORDERED,
5557 : : input_rel, ordered_rel,
5558 : : NULL);
5559 : :
5560 : : /* Let extensions possibly add some more paths */
3624 5561 [ - + ]: 41423 : if (create_upper_paths_hook)
3624 tgl@sss.pgh.pa.us 5562 :UBC 0 : (*create_upper_paths_hook) (root, UPPERREL_ORDERED,
5563 : : input_rel, ordered_rel, NULL);
5564 : :
5565 : : /*
5566 : : * No need to bother with set_cheapest here; grouping_planner does not
5567 : : * need us to do it.
5568 : : */
3660 tgl@sss.pgh.pa.us 5569 [ - + ]:CBC 41423 : Assert(ordered_rel->pathlist != NIL);
5570 : :
5571 : 41423 : return ordered_rel;
5572 : : }
5573 : :
5574 : :
5575 : : /*
5576 : : * make_group_input_target
5577 : : * Generate appropriate PathTarget for initial input to grouping nodes.
5578 : : *
5579 : : * If there is grouping or aggregation, the scan/join subplan cannot emit
5580 : : * the query's final targetlist; for example, it certainly can't emit any
5581 : : * aggregate function calls. This routine generates the correct target
5582 : : * for the scan/join subplan.
5583 : : *
5584 : : * The query target list passed from the parser already contains entries
5585 : : * for all ORDER BY and GROUP BY expressions, but it will not have entries
5586 : : * for variables used only in HAVING clauses; so we need to add those
5587 : : * variables to the subplan target list. Also, we flatten all expressions
5588 : : * except GROUP BY items into their component variables; other expressions
5589 : : * will be computed by the upper plan nodes rather than by the subplan.
5590 : : * For example, given a query like
5591 : : * SELECT a+b,SUM(c+d) FROM table GROUP BY a+b;
5592 : : * we want to pass this targetlist to the subplan:
5593 : : * a+b,c,d
5594 : : * where the a+b target will be used by the Sort/Group steps, and the
5595 : : * other targets will be used for computing the final results.
5596 : : *
5597 : : * 'final_target' is the query's final target list (in PathTarget form)
5598 : : *
5599 : : * The result is the PathTarget to be computed by the Paths returned from
5600 : : * query_planner().
5601 : : */
5602 : : static PathTarget *
3656 5603 : 23517 : make_group_input_target(PlannerInfo *root, PathTarget *final_target)
5604 : : {
7588 5605 : 23517 : Query *parse = root->parse;
5606 : : PathTarget *input_target;
5607 : : List *non_group_cols;
5608 : : List *non_group_vars;
5609 : : int i;
5610 : : ListCell *lc;
5611 : :
5612 : : /*
5613 : : * We must build a target containing all grouping columns, plus any other
5614 : : * Vars mentioned in the query's targetlist and HAVING qual.
5615 : : */
3656 5616 : 23517 : input_target = create_empty_pathtarget();
5356 5617 : 23517 : non_group_cols = NIL;
5618 : :
3656 5619 : 23517 : i = 0;
5620 [ + + + + : 58141 : foreach(lc, final_target->exprs)
+ + ]
5621 : : {
5622 : 34624 : Expr *expr = (Expr *) lfirst(lc);
3562 5623 [ + - ]: 34624 : Index sgref = get_pathtarget_sortgroupref(final_target, i);
5624 : :
1152 5625 [ + + + + : 39492 : if (sgref && root->processed_groupClause &&
+ + ]
5626 : 4868 : get_sortgroupref_clause_noerr(sgref,
5627 : : root->processed_groupClause) != NULL)
5628 : : {
5629 : : /*
5630 : : * It's a grouping column, so add it to the input target as-is.
5631 : : *
5632 : : * Note that the target is logically below the grouping step. So
5633 : : * with grouping sets we need to remove the RT index of the
5634 : : * grouping step if there is any from the target expression.
5635 : : */
551 rguo@postgresql.org 5636 [ + - + + ]: 3933 : if (parse->hasGroupRTE && parse->groupingSets != NIL)
5637 : : {
5638 [ - + ]: 1031 : Assert(root->group_rtindex > 0);
5639 : : expr = (Expr *)
5640 : 1031 : remove_nulling_relids((Node *) expr,
5641 : 1031 : bms_make_singleton(root->group_rtindex),
5642 : : NULL);
5643 : : }
3656 tgl@sss.pgh.pa.us 5644 : 3933 : add_column_to_pathtarget(input_target, expr, sgref);
5645 : : }
5646 : : else
5647 : : {
5648 : : /*
5649 : : * Non-grouping column, so just remember the expression for later
5650 : : * call to pull_var_clause.
5651 : : */
5652 : 30691 : non_group_cols = lappend(non_group_cols, expr);
5653 : : }
5654 : :
5655 : 34624 : i++;
5656 : : }
5657 : :
5658 : : /*
5659 : : * If there's a HAVING clause, we'll need the Vars it uses, too.
5660 : : */
5356 5661 [ + + ]: 23517 : if (parse->havingQual)
5662 : 481 : non_group_cols = lappend(non_group_cols, parse->havingQual);
5663 : :
5664 : : /*
5665 : : * Pull out all the Vars mentioned in non-group cols (plus HAVING), and
5666 : : * add them to the input target if not already present. (A Var used
5667 : : * directly as a GROUP BY item will be present already.) Note this
5668 : : * includes Vars used in resjunk items, so we are covering the needs of
5669 : : * ORDER BY and window specifications. Vars used within Aggrefs and
5670 : : * WindowFuncs will be pulled out here, too.
5671 : : *
5672 : : * Note that the target is logically below the grouping step. So with
5673 : : * grouping sets we need to remove the RT index of the grouping step if
5674 : : * there is any from the non-group Vars.
5675 : : */
5676 : 23517 : non_group_vars = pull_var_clause((Node *) non_group_cols,
5677 : : PVC_RECURSE_AGGREGATES |
5678 : : PVC_RECURSE_WINDOWFUNCS |
5679 : : PVC_INCLUDE_PLACEHOLDERS);
551 rguo@postgresql.org 5680 [ + + + + ]: 23517 : if (parse->hasGroupRTE && parse->groupingSets != NIL)
5681 : : {
5682 [ - + ]: 477 : Assert(root->group_rtindex > 0);
5683 : : non_group_vars = (List *)
5684 : 477 : remove_nulling_relids((Node *) non_group_vars,
5685 : 477 : bms_make_singleton(root->group_rtindex),
5686 : : NULL);
5687 : : }
3656 tgl@sss.pgh.pa.us 5688 : 23517 : add_new_columns_to_pathtarget(input_target, non_group_vars);
5689 : :
5690 : : /* clean up cruft */
5356 5691 : 23517 : list_free(non_group_vars);
5692 : 23517 : list_free(non_group_cols);
5693 : :
5694 : : /* XXX this causes some redundant cost calculation ... */
3656 5695 : 23517 : return set_pathtarget_cost_width(root, input_target);
5696 : : }
5697 : :
5698 : : /*
5699 : : * make_partial_grouping_target
5700 : : * Generate appropriate PathTarget for output of partial aggregate
5701 : : * (or partial grouping, if there are no aggregates) nodes.
5702 : : *
5703 : : * A partial aggregation node needs to emit all the same aggregates that
5704 : : * a regular aggregation node would, plus any aggregates used in HAVING;
5705 : : * except that the Aggref nodes should be marked as partial aggregates.
5706 : : *
5707 : : * In addition, we'd better emit any Vars and PlaceHolderVars that are
5708 : : * used outside of Aggrefs in the aggregation tlist and HAVING. (Presumably,
5709 : : * these would be Vars that are grouped by or used in grouping expressions.)
5710 : : *
5711 : : * grouping_target is the tlist to be emitted by the topmost aggregation step.
5712 : : * havingQual represents the HAVING clause.
5713 : : */
5714 : : static PathTarget *
2922 rhaas@postgresql.org 5715 : 1930 : make_partial_grouping_target(PlannerInfo *root,
5716 : : PathTarget *grouping_target,
5717 : : Node *havingQual)
5718 : : {
5719 : : PathTarget *partial_target;
5720 : : List *non_group_cols;
5721 : : List *non_group_exprs;
5722 : : int i;
5723 : : ListCell *lc;
5724 : :
3549 tgl@sss.pgh.pa.us 5725 : 1930 : partial_target = create_empty_pathtarget();
3646 rhaas@postgresql.org 5726 : 1930 : non_group_cols = NIL;
5727 : :
5728 : 1930 : i = 0;
3549 tgl@sss.pgh.pa.us 5729 [ + - + + : 6381 : foreach(lc, grouping_target->exprs)
+ + ]
5730 : : {
3646 rhaas@postgresql.org 5731 : 4451 : Expr *expr = (Expr *) lfirst(lc);
3549 tgl@sss.pgh.pa.us 5732 [ + - ]: 4451 : Index sgref = get_pathtarget_sortgroupref(grouping_target, i);
5733 : :
1152 5734 [ + + + + : 6839 : if (sgref && root->processed_groupClause &&
+ + ]
5735 : 2388 : get_sortgroupref_clause_noerr(sgref,
5736 : : root->processed_groupClause) != NULL)
5737 : : {
5738 : : /*
5739 : : * It's a grouping column, so add it to the partial_target as-is.
5740 : : * (This allows the upper agg step to repeat the grouping calcs.)
5741 : : */
3549 5742 : 1414 : add_column_to_pathtarget(partial_target, expr, sgref);
5743 : : }
5744 : : else
5745 : : {
5746 : : /*
5747 : : * Non-grouping column, so just remember the expression for later
5748 : : * call to pull_var_clause.
5749 : : */
3646 rhaas@postgresql.org 5750 : 3037 : non_group_cols = lappend(non_group_cols, expr);
5751 : : }
5752 : :
5753 : 4451 : i++;
5754 : : }
5755 : :
5756 : : /*
5757 : : * If there's a HAVING clause, we'll need the Vars/Aggrefs it uses, too.
5758 : : */
2922 5759 [ + + ]: 1930 : if (havingQual)
5760 : 439 : non_group_cols = lappend(non_group_cols, havingQual);
5761 : :
5762 : : /*
5763 : : * Pull out all the Vars, PlaceHolderVars, and Aggrefs mentioned in
5764 : : * non-group cols (plus HAVING), and add them to the partial_target if not
5765 : : * already present. (An expression used directly as a GROUP BY item will
5766 : : * be present already.) Note this includes Vars used in resjunk items, so
5767 : : * we are covering the needs of ORDER BY and window specifications.
5768 : : */
3646 5769 : 1930 : non_group_exprs = pull_var_clause((Node *) non_group_cols,
5770 : : PVC_INCLUDE_AGGREGATES |
5771 : : PVC_RECURSE_WINDOWFUNCS |
5772 : : PVC_INCLUDE_PLACEHOLDERS);
5773 : :
3549 tgl@sss.pgh.pa.us 5774 : 1930 : add_new_columns_to_pathtarget(partial_target, non_group_exprs);
5775 : :
5776 : : /*
5777 : : * Adjust Aggrefs to put them in partial mode. At this point all Aggrefs
5778 : : * are at the top level of the target list, so we can just scan the list
5779 : : * rather than recursing through the expression trees.
5780 : : */
5781 [ + - + + : 6679 : foreach(lc, partial_target->exprs)
+ + ]
5782 : : {
5783 : 4749 : Aggref *aggref = (Aggref *) lfirst(lc);
5784 : :
5785 [ + + ]: 4749 : if (IsA(aggref, Aggref))
5786 : : {
5787 : : Aggref *newaggref;
5788 : :
5789 : : /*
5790 : : * We shouldn't need to copy the substructure of the Aggref node,
5791 : : * but flat-copy the node itself to avoid damaging other trees.
5792 : : */
5793 : 3320 : newaggref = makeNode(Aggref);
5794 : 3320 : memcpy(newaggref, aggref, sizeof(Aggref));
5795 : :
5796 : : /* For now, assume serialization is required */
5797 : 3320 : mark_partial_aggref(newaggref, AGGSPLIT_INITIAL_SERIAL);
5798 : :
5799 : 3320 : lfirst(lc) = newaggref;
5800 : : }
5801 : : }
5802 : :
5803 : : /* clean up cruft */
3646 rhaas@postgresql.org 5804 : 1930 : list_free(non_group_exprs);
5805 : 1930 : list_free(non_group_cols);
5806 : :
5807 : : /* XXX this causes some redundant cost calculation ... */
3549 tgl@sss.pgh.pa.us 5808 : 1930 : return set_pathtarget_cost_width(root, partial_target);
5809 : : }
5810 : :
5811 : : /*
5812 : : * mark_partial_aggref
5813 : : * Adjust an Aggref to make it represent a partial-aggregation step.
5814 : : *
5815 : : * The Aggref node is modified in-place; caller must do any copying required.
5816 : : */
5817 : : void
5818 : 9296 : mark_partial_aggref(Aggref *agg, AggSplit aggsplit)
5819 : : {
5820 : : /* aggtranstype should be computed by this point */
5821 [ - + ]: 9296 : Assert(OidIsValid(agg->aggtranstype));
5822 : : /* ... but aggsplit should still be as the parser left it */
5823 [ - + ]: 9296 : Assert(agg->aggsplit == AGGSPLIT_SIMPLE);
5824 : :
5825 : : /* Mark the Aggref with the intended partial-aggregation mode */
5826 : 9296 : agg->aggsplit = aggsplit;
5827 : :
5828 : : /*
5829 : : * Adjust result type if needed. Normally, a partial aggregate returns
5830 : : * the aggregate's transition type; but if that's INTERNAL and we're
5831 : : * serializing, it returns BYTEA instead.
5832 : : */
5833 [ + + ]: 9296 : if (DO_AGGSPLIT_SKIPFINAL(aggsplit))
5834 : : {
5835 [ + + + - ]: 8141 : if (agg->aggtranstype == INTERNALOID && DO_AGGSPLIT_SERIALIZE(aggsplit))
5836 : 157 : agg->aggtype = BYTEAOID;
5837 : : else
5838 : 7984 : agg->aggtype = agg->aggtranstype;
5839 : : }
3646 rhaas@postgresql.org 5840 : 9296 : }
5841 : :
5842 : : /*
5843 : : * postprocess_setop_tlist
5844 : : * Fix up targetlist returned by plan_set_operations().
5845 : : *
5846 : : * We need to transpose sort key info from the orig_tlist into new_tlist.
5847 : : * NOTE: this would not be good enough if we supported resjunk sort keys
5848 : : * for results of set operations --- then, we'd need to project a whole
5849 : : * new tlist to evaluate the resjunk columns. For now, just ereport if we
5850 : : * find any resjunk columns in orig_tlist.
5851 : : */
5852 : : static List *
9257 tgl@sss.pgh.pa.us 5853 : 3298 : postprocess_setop_tlist(List *new_tlist, List *orig_tlist)
5854 : : {
5855 : : ListCell *l;
7963 neilc@samurai.com 5856 : 3298 : ListCell *orig_tlist_item = list_head(orig_tlist);
5857 : :
9257 tgl@sss.pgh.pa.us 5858 [ + + + + : 12953 : foreach(l, new_tlist)
+ + ]
5859 : : {
3113 5860 : 9655 : TargetEntry *new_tle = lfirst_node(TargetEntry, l);
5861 : : TargetEntry *orig_tle;
5862 : :
5863 : : /* ignore resjunk columns in setop result */
7648 5864 [ - + ]: 9655 : if (new_tle->resjunk)
9257 tgl@sss.pgh.pa.us 5865 :UBC 0 : continue;
5866 : :
7963 neilc@samurai.com 5867 [ - + ]:CBC 9655 : Assert(orig_tlist_item != NULL);
3113 tgl@sss.pgh.pa.us 5868 : 9655 : orig_tle = lfirst_node(TargetEntry, orig_tlist_item);
2435 5869 : 9655 : orig_tlist_item = lnext(orig_tlist, orig_tlist_item);
7456 bruce@momjian.us 5870 [ - + ]: 9655 : if (orig_tle->resjunk) /* should not happen */
8269 tgl@sss.pgh.pa.us 5871 [ # # ]:UBC 0 : elog(ERROR, "resjunk output columns are not implemented");
7648 tgl@sss.pgh.pa.us 5872 [ - + ]:CBC 9655 : Assert(new_tle->resno == orig_tle->resno);
5873 : 9655 : new_tle->ressortgroupref = orig_tle->ressortgroupref;
5874 : : }
7963 neilc@samurai.com 5875 [ - + ]: 3298 : if (orig_tlist_item != NULL)
8269 tgl@sss.pgh.pa.us 5876 [ # # ]:UBC 0 : elog(ERROR, "resjunk output columns are not implemented");
9257 tgl@sss.pgh.pa.us 5877 :CBC 3298 : return new_tlist;
5878 : : }
5879 : :
5880 : : /*
5881 : : * optimize_window_clauses
5882 : : * Call each WindowFunc's prosupport function to see if we're able to
5883 : : * make any adjustments to any of the WindowClause's so that the executor
5884 : : * can execute the window functions in a more optimal way.
5885 : : *
5886 : : * Currently we only allow adjustments to the WindowClause's frameOptions. We
5887 : : * may allow more things to be done here in the future.
5888 : : */
5889 : : static void
1178 drowley@postgresql.o 5890 : 1338 : optimize_window_clauses(PlannerInfo *root, WindowFuncLists *wflists)
5891 : : {
5892 : 1338 : List *windowClause = root->parse->windowClause;
5893 : : ListCell *lc;
5894 : :
5895 [ + - + + : 2799 : foreach(lc, windowClause)
+ + ]
5896 : : {
5897 : 1461 : WindowClause *wc = lfirst_node(WindowClause, lc);
5898 : : ListCell *lc2;
5899 : 1461 : int optimizedFrameOptions = 0;
5900 : :
5901 [ - + ]: 1461 : Assert(wc->winref <= wflists->maxWinRef);
5902 : :
5903 : : /* skip any WindowClauses that have no WindowFuncs */
5904 [ + + ]: 1461 : if (wflists->windowFuncs[wc->winref] == NIL)
5905 : 12 : continue;
5906 : :
5907 [ + - + + : 1776 : foreach(lc2, wflists->windowFuncs[wc->winref])
+ + ]
5908 : : {
5909 : : SupportRequestOptimizeWindowClause req;
5910 : : SupportRequestOptimizeWindowClause *res;
5911 : 1470 : WindowFunc *wfunc = lfirst_node(WindowFunc, lc2);
5912 : : Oid prosupport;
5913 : :
5914 : 1470 : prosupport = get_func_support(wfunc->winfnoid);
5915 : :
5916 : : /* Check if there's a support function for 'wfunc' */
5917 [ + + ]: 1470 : if (!OidIsValid(prosupport))
5918 : 1143 : break; /* can't optimize this WindowClause */
5919 : :
5920 : 440 : req.type = T_SupportRequestOptimizeWindowClause;
5921 : 440 : req.window_clause = wc;
5922 : 440 : req.window_func = wfunc;
5923 : 440 : req.frameOptions = wc->frameOptions;
5924 : :
5925 : : /* call the support function */
5926 : : res = (SupportRequestOptimizeWindowClause *)
5927 : 440 : DatumGetPointer(OidFunctionCall1(prosupport,
5928 : : PointerGetDatum(&req)));
5929 : :
5930 : : /*
5931 : : * Skip to next WindowClause if the support function does not
5932 : : * support this request type.
5933 : : */
5934 [ + + ]: 440 : if (res == NULL)
5935 : 113 : break;
5936 : :
5937 : : /*
5938 : : * Save these frameOptions for the first WindowFunc for this
5939 : : * WindowClause.
5940 : : */
5941 [ + + ]: 327 : if (foreach_current_index(lc2) == 0)
5942 : 315 : optimizedFrameOptions = res->frameOptions;
5943 : :
5944 : : /*
5945 : : * On subsequent WindowFuncs, if the frameOptions are not the same
5946 : : * then we're unable to optimize the frameOptions for this
5947 : : * WindowClause.
5948 : : */
5949 [ - + ]: 12 : else if (optimizedFrameOptions != res->frameOptions)
1178 drowley@postgresql.o 5950 :UBC 0 : break; /* skip to the next WindowClause, if any */
5951 : : }
5952 : :
5953 : : /* adjust the frameOptions if all WindowFunc's agree that it's ok */
1178 drowley@postgresql.o 5954 [ + + + - ]:CBC 1449 : if (lc2 == NULL && wc->frameOptions != optimizedFrameOptions)
5955 : : {
5956 : : ListCell *lc3;
5957 : :
5958 : : /* apply the new frame options */
5959 : 306 : wc->frameOptions = optimizedFrameOptions;
5960 : :
5961 : : /*
5962 : : * We now check to see if changing the frameOptions has caused
5963 : : * this WindowClause to be a duplicate of some other WindowClause.
5964 : : * This can only happen if we have multiple WindowClauses, so
5965 : : * don't bother if there's only 1.
5966 : : */
5967 [ + + ]: 306 : if (list_length(windowClause) == 1)
5968 : 261 : continue;
5969 : :
5970 : : /*
5971 : : * Do the duplicate check and reuse the existing WindowClause if
5972 : : * we find a duplicate.
5973 : : */
5974 [ + - + + : 114 : foreach(lc3, windowClause)
+ + ]
5975 : : {
5976 : 87 : WindowClause *existing_wc = lfirst_node(WindowClause, lc3);
5977 : :
5978 : : /* skip over the WindowClause we're currently editing */
5979 [ + + ]: 87 : if (existing_wc == wc)
5980 : 27 : continue;
5981 : :
5982 : : /*
5983 : : * Perform the same duplicate check that is done in
5984 : : * transformWindowFuncCall.
5985 : : */
5986 [ + - + + ]: 120 : if (equal(wc->partitionClause, existing_wc->partitionClause) &&
5987 : 60 : equal(wc->orderClause, existing_wc->orderClause) &&
5988 [ + + + - ]: 60 : wc->frameOptions == existing_wc->frameOptions &&
5989 [ + - ]: 36 : equal(wc->startOffset, existing_wc->startOffset) &&
5990 : 18 : equal(wc->endOffset, existing_wc->endOffset))
5991 : : {
5992 : : ListCell *lc4;
5993 : :
5994 : : /*
5995 : : * Now move each WindowFunc in 'wc' into 'existing_wc'.
5996 : : * This required adjusting each WindowFunc's winref and
5997 : : * moving the WindowFuncs in 'wc' to the list of
5998 : : * WindowFuncs in 'existing_wc'.
5999 : : */
6000 [ + - + + : 39 : foreach(lc4, wflists->windowFuncs[wc->winref])
+ + ]
6001 : : {
6002 : 21 : WindowFunc *wfunc = lfirst_node(WindowFunc, lc4);
6003 : :
6004 : 21 : wfunc->winref = existing_wc->winref;
6005 : : }
6006 : :
6007 : : /* move list items */
6008 : 36 : wflists->windowFuncs[existing_wc->winref] = list_concat(wflists->windowFuncs[existing_wc->winref],
6009 : 18 : wflists->windowFuncs[wc->winref]);
6010 : 18 : wflists->windowFuncs[wc->winref] = NIL;
6011 : :
6012 : : /*
6013 : : * transformWindowFuncCall() should have made sure there
6014 : : * are no other duplicates, so we needn't bother looking
6015 : : * any further.
6016 : : */
6017 : 18 : break;
6018 : : }
6019 : : }
6020 : : }
6021 : : }
6022 : 1338 : }
6023 : :
6024 : : /*
6025 : : * select_active_windows
6026 : : * Create a list of the "active" window clauses (ie, those referenced
6027 : : * by non-deleted WindowFuncs) in the order they are to be executed.
6028 : : */
6029 : : static List *
6286 tgl@sss.pgh.pa.us 6030 : 1338 : select_active_windows(PlannerInfo *root, WindowFuncLists *wflists)
6031 : : {
2739 rhodiumtoad@postgres 6032 : 1338 : List *windowClause = root->parse->windowClause;
6033 : 1338 : List *result = NIL;
6034 : : ListCell *lc;
6035 : 1338 : int nActive = 0;
95 michael@paquier.xyz 6036 :GNC 1338 : WindowClauseSortData *actives = palloc_array(WindowClauseSortData,
6037 : : list_length(windowClause));
6038 : :
6039 : : /* First, construct an array of the active windows */
2739 rhodiumtoad@postgres 6040 [ + - + + :CBC 2799 : foreach(lc, windowClause)
+ + ]
6041 : : {
3113 tgl@sss.pgh.pa.us 6042 : 1461 : WindowClause *wc = lfirst_node(WindowClause, lc);
6043 : :
6044 : : /* It's only active if wflists shows some related WindowFuncs */
6286 6045 [ - + ]: 1461 : Assert(wc->winref <= wflists->maxWinRef);
2739 rhodiumtoad@postgres 6046 [ + + ]: 1461 : if (wflists->windowFuncs[wc->winref] == NIL)
6047 : 30 : continue;
6048 : :
6049 : 1431 : actives[nActive].wc = wc; /* original clause */
6050 : :
6051 : : /*
6052 : : * For sorting, we want the list of partition keys followed by the
6053 : : * list of sort keys. But pathkeys construction will remove duplicates
6054 : : * between the two, so we can as well (even though we can't detect all
6055 : : * of the duplicates, since some may come from ECs - that might mean
6056 : : * we miss optimization chances here). We must, however, ensure that
6057 : : * the order of entries is preserved with respect to the ones we do
6058 : : * keep.
6059 : : *
6060 : : * partitionClause and orderClause had their own duplicates removed in
6061 : : * parse analysis, so we're only concerned here with removing
6062 : : * orderClause entries that also appear in partitionClause.
6063 : : */
6064 : 2862 : actives[nActive].uniqueOrder =
6065 : 1431 : list_concat_unique(list_copy(wc->partitionClause),
6066 : 1431 : wc->orderClause);
6067 : 1431 : nActive++;
6068 : : }
6069 : :
6070 : : /*
6071 : : * Sort active windows by their partitioning/ordering clauses, ignoring
6072 : : * any framing clauses, so that the windows that need the same sorting are
6073 : : * adjacent in the list. When we come to generate paths, this will avoid
6074 : : * inserting additional Sort nodes.
6075 : : *
6076 : : * This is how we implement a specific requirement from the SQL standard,
6077 : : * which says that when two or more windows are order-equivalent (i.e.
6078 : : * have matching partition and order clauses, even if their names or
6079 : : * framing clauses differ), then all peer rows must be presented in the
6080 : : * same order in all of them. If we allowed multiple sort nodes for such
6081 : : * cases, we'd risk having the peer rows end up in different orders in
6082 : : * equivalent windows due to sort instability. (See General Rule 4 of
6083 : : * <window clause> in SQL2008 - SQL2016.)
6084 : : *
6085 : : * Additionally, if the entire list of clauses of one window is a prefix
6086 : : * of another, put first the window with stronger sorting requirements.
6087 : : * This way we will first sort for stronger window, and won't have to sort
6088 : : * again for the weaker one.
6089 : : */
6090 : 1338 : qsort(actives, nActive, sizeof(WindowClauseSortData), common_prefix_cmp);
6091 : :
6092 : : /* build ordered list of the original WindowClause nodes */
6093 [ + + ]: 2769 : for (int i = 0; i < nActive; i++)
6094 : 1431 : result = lappend(result, actives[i].wc);
6095 : :
6096 : 1338 : pfree(actives);
6097 : :
6098 : 1338 : return result;
6099 : : }
6100 : :
6101 : : /*
6102 : : * name_active_windows
6103 : : * Ensure all active windows have unique names.
6104 : : *
6105 : : * The parser will have checked that user-assigned window names are unique
6106 : : * within the Query. Here we assign made-up names to any unnamed
6107 : : * WindowClauses for the benefit of EXPLAIN. (We don't want to do this
6108 : : * at parse time, because it'd mess up decompilation of views.)
6109 : : *
6110 : : * activeWindows: result of select_active_windows
6111 : : */
6112 : : static void
369 tgl@sss.pgh.pa.us 6113 : 1338 : name_active_windows(List *activeWindows)
6114 : : {
6115 : 1338 : int next_n = 1;
6116 : : char newname[16];
6117 : : ListCell *lc;
6118 : :
6119 [ + - + + : 2769 : foreach(lc, activeWindows)
+ + ]
6120 : : {
6121 : 1431 : WindowClause *wc = lfirst_node(WindowClause, lc);
6122 : :
6123 : : /* Nothing to do if it has a name already. */
6124 [ + + ]: 1431 : if (wc->name)
6125 : 288 : continue;
6126 : :
6127 : : /* Select a name not currently present in the list. */
6128 : : for (;;)
6129 : 3 : {
6130 : : ListCell *lc2;
6131 : :
6132 : 1146 : snprintf(newname, sizeof(newname), "w%d", next_n++);
6133 [ + - + + : 2466 : foreach(lc2, activeWindows)
+ + ]
6134 : : {
6135 : 1323 : WindowClause *wc2 = lfirst_node(WindowClause, lc2);
6136 : :
6137 [ + + + + ]: 1323 : if (wc2->name && strcmp(wc2->name, newname) == 0)
6138 : 3 : break; /* matched */
6139 : : }
6140 [ + + ]: 1146 : if (lc2 == NULL)
6141 : 1143 : break; /* reached the end with no match */
6142 : : }
6143 : 1143 : wc->name = pstrdup(newname);
6144 : : }
6145 : 1338 : }
6146 : :
6147 : : /*
6148 : : * common_prefix_cmp
6149 : : * QSort comparison function for WindowClauseSortData
6150 : : *
6151 : : * Sort the windows by the required sorting clauses. First, compare the sort
6152 : : * clauses themselves. Second, if one window's clauses are a prefix of another
6153 : : * one's clauses, put the window with more sort clauses first.
6154 : : *
6155 : : * We purposefully sort by the highest tleSortGroupRef first. Since
6156 : : * tleSortGroupRefs are assigned for the query's DISTINCT and ORDER BY first
6157 : : * and because here we sort the lowest tleSortGroupRefs last, if a
6158 : : * WindowClause is sharing a tleSortGroupRef with the query's DISTINCT or
6159 : : * ORDER BY clause, this makes it more likely that the final WindowAgg will
6160 : : * provide presorted input for the query's DISTINCT or ORDER BY clause, thus
6161 : : * reducing the total number of sorts required for the query.
6162 : : */
6163 : : static int
2739 rhodiumtoad@postgres 6164 : 102 : common_prefix_cmp(const void *a, const void *b)
6165 : : {
6166 : 102 : const WindowClauseSortData *wcsa = a;
6167 : 102 : const WindowClauseSortData *wcsb = b;
6168 : : ListCell *item_a;
6169 : : ListCell *item_b;
6170 : :
6171 [ + + + + : 183 : forboth(item_a, wcsa->uniqueOrder, item_b, wcsb->uniqueOrder)
+ + + + +
+ + + +
+ ]
6172 : : {
6173 : 132 : SortGroupClause *sca = lfirst_node(SortGroupClause, item_a);
6174 : 132 : SortGroupClause *scb = lfirst_node(SortGroupClause, item_b);
6175 : :
6176 [ + + ]: 132 : if (sca->tleSortGroupRef > scb->tleSortGroupRef)
6177 : 51 : return -1;
6178 [ + + ]: 126 : else if (sca->tleSortGroupRef < scb->tleSortGroupRef)
6179 : 33 : return 1;
6180 [ - + ]: 93 : else if (sca->sortop > scb->sortop)
2739 rhodiumtoad@postgres 6181 :UBC 0 : return -1;
2739 rhodiumtoad@postgres 6182 [ + + ]:CBC 93 : else if (sca->sortop < scb->sortop)
6183 : 12 : return 1;
6184 [ - + - - ]: 81 : else if (sca->nulls_first && !scb->nulls_first)
2739 rhodiumtoad@postgres 6185 :UBC 0 : return -1;
2739 rhodiumtoad@postgres 6186 [ + - - + ]:CBC 81 : else if (!sca->nulls_first && scb->nulls_first)
2739 rhodiumtoad@postgres 6187 :UBC 0 : return 1;
6188 : : /* no need to compare eqop, since it is fully determined by sortop */
6189 : : }
6190 : :
2739 rhodiumtoad@postgres 6191 [ + + ]:CBC 51 : if (list_length(wcsa->uniqueOrder) > list_length(wcsb->uniqueOrder))
6192 : 3 : return -1;
6193 [ + + ]: 48 : else if (list_length(wcsa->uniqueOrder) < list_length(wcsb->uniqueOrder))
6194 : 15 : return 1;
6195 : :
6196 : 33 : return 0;
6197 : : }
6198 : :
6199 : : /*
6200 : : * make_window_input_target
6201 : : * Generate appropriate PathTarget for initial input to WindowAgg nodes.
6202 : : *
6203 : : * When the query has window functions, this function computes the desired
6204 : : * target to be computed by the node just below the first WindowAgg.
6205 : : * This tlist must contain all values needed to evaluate the window functions,
6206 : : * compute the final target list, and perform any required final sort step.
6207 : : * If multiple WindowAggs are needed, each intermediate one adds its window
6208 : : * function results onto this base tlist; only the topmost WindowAgg computes
6209 : : * the actual desired target list.
6210 : : *
6211 : : * This function is much like make_group_input_target, though not quite enough
6212 : : * like it to share code. As in that function, we flatten most expressions
6213 : : * into their component variables. But we do not want to flatten window
6214 : : * PARTITION BY/ORDER BY clauses, since that might result in multiple
6215 : : * evaluations of them, which would be bad (possibly even resulting in
6216 : : * inconsistent answers, if they contain volatile functions).
6217 : : * Also, we must not flatten GROUP BY clauses that were left unflattened by
6218 : : * make_group_input_target, because we may no longer have access to the
6219 : : * individual Vars in them.
6220 : : *
6221 : : * Another key difference from make_group_input_target is that we don't
6222 : : * flatten Aggref expressions, since those are to be computed below the
6223 : : * window functions and just referenced like Vars above that.
6224 : : *
6225 : : * 'final_target' is the query's final target list (in PathTarget form)
6226 : : * 'activeWindows' is the list of active windows previously identified by
6227 : : * select_active_windows.
6228 : : *
6229 : : * The result is the PathTarget to be computed by the plan node immediately
6230 : : * below the first WindowAgg node.
6231 : : */
6232 : : static PathTarget *
3658 tgl@sss.pgh.pa.us 6233 : 1338 : make_window_input_target(PlannerInfo *root,
6234 : : PathTarget *final_target,
6235 : : List *activeWindows)
6236 : : {
6237 : : PathTarget *input_target;
6238 : : Bitmapset *sgrefs;
6239 : : List *flattenable_cols;
6240 : : List *flattenable_vars;
6241 : : int i;
6242 : : ListCell *lc;
6243 : :
1152 6244 [ - + ]: 1338 : Assert(root->parse->hasWindowFuncs);
6245 : :
6246 : : /*
6247 : : * Collect the sortgroupref numbers of window PARTITION/ORDER BY clauses
6248 : : * into a bitmapset for convenient reference below.
6249 : : */
4931 6250 : 1338 : sgrefs = NULL;
6194 6251 [ + - + + : 2769 : foreach(lc, activeWindows)
+ + ]
6252 : : {
3113 6253 : 1431 : WindowClause *wc = lfirst_node(WindowClause, lc);
6254 : : ListCell *lc2;
6255 : :
6194 6256 [ + + + + : 1809 : foreach(lc2, wc->partitionClause)
+ + ]
6257 : : {
3113 6258 : 378 : SortGroupClause *sortcl = lfirst_node(SortGroupClause, lc2);
6259 : :
6194 6260 : 378 : sgrefs = bms_add_member(sgrefs, sortcl->tleSortGroupRef);
6261 : : }
6262 [ + + + + : 2567 : foreach(lc2, wc->orderClause)
+ + ]
6263 : : {
3113 6264 : 1136 : SortGroupClause *sortcl = lfirst_node(SortGroupClause, lc2);
6265 : :
6194 6266 : 1136 : sgrefs = bms_add_member(sgrefs, sortcl->tleSortGroupRef);
6267 : : }
6268 : : }
6269 : :
6270 : : /* Add in sortgroupref numbers of GROUP BY clauses, too */
1152 6271 [ + + + + : 1434 : foreach(lc, root->processed_groupClause)
+ + ]
6272 : : {
3113 6273 : 96 : SortGroupClause *grpcl = lfirst_node(SortGroupClause, lc);
6274 : :
4931 6275 : 96 : sgrefs = bms_add_member(sgrefs, grpcl->tleSortGroupRef);
6276 : : }
6277 : :
6278 : : /*
6279 : : * Construct a target containing all the non-flattenable targetlist items,
6280 : : * and save aside the others for a moment.
6281 : : */
3656 6282 : 1338 : input_target = create_empty_pathtarget();
4931 6283 : 1338 : flattenable_cols = NIL;
6284 : :
3656 6285 : 1338 : i = 0;
6286 [ + - + + : 5614 : foreach(lc, final_target->exprs)
+ + ]
6287 : : {
6288 : 4276 : Expr *expr = (Expr *) lfirst(lc);
3562 6289 [ + - ]: 4276 : Index sgref = get_pathtarget_sortgroupref(final_target, i);
6290 : :
6291 : : /*
6292 : : * Don't want to deconstruct window clauses or GROUP BY items. (Note
6293 : : * that such items can't contain window functions, so it's okay to
6294 : : * compute them below the WindowAgg nodes.)
6295 : : */
3656 6296 [ + + + + ]: 4276 : if (sgref != 0 && bms_is_member(sgref, sgrefs))
6297 : : {
6298 : : /*
6299 : : * Don't want to deconstruct this value, so add it to the input
6300 : : * target as-is.
6301 : : */
6302 : 1432 : add_column_to_pathtarget(input_target, expr, sgref);
6303 : : }
6304 : : else
6305 : : {
6306 : : /*
6307 : : * Column is to be flattened, so just remember the expression for
6308 : : * later call to pull_var_clause.
6309 : : */
6310 : 2844 : flattenable_cols = lappend(flattenable_cols, expr);
6311 : : }
6312 : :
6313 : 4276 : i++;
6314 : : }
6315 : :
6316 : : /*
6317 : : * Pull out all the Vars and Aggrefs mentioned in flattenable columns, and
6318 : : * add them to the input target if not already present. (Some might be
6319 : : * there already because they're used directly as window/group clauses.)
6320 : : *
6321 : : * Note: it's essential to use PVC_INCLUDE_AGGREGATES here, so that any
6322 : : * Aggrefs are placed in the Agg node's tlist and not left to be computed
6323 : : * at higher levels. On the other hand, we should recurse into
6324 : : * WindowFuncs to make sure their input expressions are available.
6325 : : */
4931 6326 : 1338 : flattenable_vars = pull_var_clause((Node *) flattenable_cols,
6327 : : PVC_INCLUDE_AGGREGATES |
6328 : : PVC_RECURSE_WINDOWFUNCS |
6329 : : PVC_INCLUDE_PLACEHOLDERS);
3656 6330 : 1338 : add_new_columns_to_pathtarget(input_target, flattenable_vars);
6331 : :
6332 : : /* clean up cruft */
4931 6333 : 1338 : list_free(flattenable_vars);
6334 : 1338 : list_free(flattenable_cols);
6335 : :
6336 : : /* XXX this causes some redundant cost calculation ... */
3656 6337 : 1338 : return set_pathtarget_cost_width(root, input_target);
6338 : : }
6339 : :
6340 : : /*
6341 : : * make_pathkeys_for_window
6342 : : * Create a pathkeys list describing the required input ordering
6343 : : * for the given WindowClause.
6344 : : *
6345 : : * Modifies wc's partitionClause to remove any clauses which are deemed
6346 : : * redundant by the pathkey logic.
6347 : : *
6348 : : * The required ordering is first the PARTITION keys, then the ORDER keys.
6349 : : * In the future we might try to implement windowing using hashing, in which
6350 : : * case the ordering could be relaxed, but for now we always sort.
6351 : : */
6352 : : static List *
6286 6353 : 2876 : make_pathkeys_for_window(PlannerInfo *root, WindowClause *wc,
6354 : : List *tlist)
6355 : : {
986 drowley@postgresql.o 6356 : 2876 : List *window_pathkeys = NIL;
6357 : :
6358 : : /* Throw error if can't sort */
6286 tgl@sss.pgh.pa.us 6359 [ - + ]: 2876 : if (!grouping_is_sortable(wc->partitionClause))
6286 tgl@sss.pgh.pa.us 6360 [ # # ]:UBC 0 : ereport(ERROR,
6361 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6362 : : errmsg("could not implement window PARTITION BY"),
6363 : : errdetail("Window partitioning columns must be of sortable datatypes.")));
6286 tgl@sss.pgh.pa.us 6364 [ - + ]:CBC 2876 : if (!grouping_is_sortable(wc->orderClause))
6286 tgl@sss.pgh.pa.us 6365 [ # # ]:UBC 0 : ereport(ERROR,
6366 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6367 : : errmsg("could not implement window ORDER BY"),
6368 : : errdetail("Window ordering columns must be of sortable datatypes.")));
6369 : :
6370 : : /*
6371 : : * First fetch the pathkeys for the PARTITION BY clause. We can safely
6372 : : * remove any clauses from the wc->partitionClause for redundant pathkeys.
6373 : : */
986 drowley@postgresql.o 6374 [ + + ]:CBC 2876 : if (wc->partitionClause != NIL)
6375 : : {
6376 : : bool sortable;
6377 : :
6378 : 660 : window_pathkeys = make_pathkeys_for_sortclauses_extended(root,
6379 : : &wc->partitionClause,
6380 : : tlist,
6381 : : true,
6382 : : false,
6383 : : &sortable,
6384 : : false);
6385 : :
6386 [ - + ]: 660 : Assert(sortable);
6387 : : }
6388 : :
6389 : : /*
6390 : : * In principle, we could also consider removing redundant ORDER BY items
6391 : : * too as doing so does not alter the result of peer row checks done by
6392 : : * the executor. However, we must *not* remove the ordering column for
6393 : : * RANGE OFFSET cases, as the executor needs that for in_range tests even
6394 : : * if it's known to be equal to some partitioning column.
6395 : : */
6396 [ + + ]: 2876 : if (wc->orderClause != NIL)
6397 : : {
6398 : : List *orderby_pathkeys;
6399 : :
6400 : 2225 : orderby_pathkeys = make_pathkeys_for_sortclauses(root,
6401 : : wc->orderClause,
6402 : : tlist);
6403 : :
6404 : : /* Okay, make the combined pathkeys */
6405 [ + + ]: 2225 : if (window_pathkeys != NIL)
6406 : 473 : window_pathkeys = append_pathkeys(window_pathkeys, orderby_pathkeys);
6407 : : else
6408 : 1752 : window_pathkeys = orderby_pathkeys;
6409 : : }
6410 : :
6286 tgl@sss.pgh.pa.us 6411 : 2876 : return window_pathkeys;
6412 : : }
6413 : :
6414 : : /*
6415 : : * make_sort_input_target
6416 : : * Generate appropriate PathTarget for initial input to Sort step.
6417 : : *
6418 : : * If the query has ORDER BY, this function chooses the target to be computed
6419 : : * by the node just below the Sort (and DISTINCT, if any, since Unique can't
6420 : : * project) steps. This might or might not be identical to the query's final
6421 : : * output target.
6422 : : *
6423 : : * The main argument for keeping the sort-input tlist the same as the final
6424 : : * is that we avoid a separate projection node (which will be needed if
6425 : : * they're different, because Sort can't project). However, there are also
6426 : : * advantages to postponing tlist evaluation till after the Sort: it ensures
6427 : : * a consistent order of evaluation for any volatile functions in the tlist,
6428 : : * and if there's also a LIMIT, we can stop the query without ever computing
6429 : : * tlist functions for later rows, which is beneficial for both volatile and
6430 : : * expensive functions.
6431 : : *
6432 : : * Our current policy is to postpone volatile expressions till after the sort
6433 : : * unconditionally (assuming that that's possible, ie they are in plain tlist
6434 : : * columns and not ORDER BY/GROUP BY/DISTINCT columns). We also prefer to
6435 : : * postpone set-returning expressions, because running them beforehand would
6436 : : * bloat the sort dataset, and because it might cause unexpected output order
6437 : : * if the sort isn't stable. However there's a constraint on that: all SRFs
6438 : : * in the tlist should be evaluated at the same plan step, so that they can
6439 : : * run in sync in nodeProjectSet. So if any SRFs are in sort columns, we
6440 : : * mustn't postpone any SRFs. (Note that in principle that policy should
6441 : : * probably get applied to the group/window input targetlists too, but we
6442 : : * have not done that historically.) Lastly, expensive expressions are
6443 : : * postponed if there is a LIMIT, or if root->tuple_fraction shows that
6444 : : * partial evaluation of the query is possible (if neither is true, we expect
6445 : : * to have to evaluate the expressions for every row anyway), or if there are
6446 : : * any volatile or set-returning expressions (since once we've put in a
6447 : : * projection at all, it won't cost any more to postpone more stuff).
6448 : : *
6449 : : * Another issue that could potentially be considered here is that
6450 : : * evaluating tlist expressions could result in data that's either wider
6451 : : * or narrower than the input Vars, thus changing the volume of data that
6452 : : * has to go through the Sort. However, we usually have only a very bad
6453 : : * idea of the output width of any expression more complex than a Var,
6454 : : * so for now it seems too risky to try to optimize on that basis.
6455 : : *
6456 : : * Note that if we do produce a modified sort-input target, and then the
6457 : : * query ends up not using an explicit Sort, no particular harm is done:
6458 : : * we'll initially use the modified target for the preceding path nodes,
6459 : : * but then change them to the final target with apply_projection_to_path.
6460 : : * Moreover, in such a case the guarantees about evaluation order of
6461 : : * volatile functions still hold, since the rows are sorted already.
6462 : : *
6463 : : * This function has some things in common with make_group_input_target and
6464 : : * make_window_input_target, though the detailed rules for what to do are
6465 : : * different. We never flatten/postpone any grouping or ordering columns;
6466 : : * those are needed before the sort. If we do flatten a particular
6467 : : * expression, we leave Aggref and WindowFunc nodes alone, since those were
6468 : : * computed earlier.
6469 : : *
6470 : : * 'final_target' is the query's final target list (in PathTarget form)
6471 : : * 'have_postponed_srfs' is an output argument, see below
6472 : : *
6473 : : * The result is the PathTarget to be computed by the plan node immediately
6474 : : * below the Sort step (and the Distinct step, if any). This will be
6475 : : * exactly final_target if we decide a projection step wouldn't be helpful.
6476 : : *
6477 : : * In addition, *have_postponed_srfs is set to true if we choose to postpone
6478 : : * any set-returning functions to after the Sort.
6479 : : */
6480 : : static PathTarget *
3656 6481 : 39353 : make_sort_input_target(PlannerInfo *root,
6482 : : PathTarget *final_target,
6483 : : bool *have_postponed_srfs)
6484 : : {
6485 : 39353 : Query *parse = root->parse;
6486 : : PathTarget *input_target;
6487 : : int ncols;
6488 : : bool *col_is_srf;
6489 : : bool *postpone_col;
6490 : : bool have_srf;
6491 : : bool have_volatile;
6492 : : bool have_expensive;
6493 : : bool have_srf_sortcols;
6494 : : bool postpone_srfs;
6495 : : List *postponable_cols;
6496 : : List *postponable_vars;
6497 : : int i;
6498 : : ListCell *lc;
6499 : :
6500 : : /* Shouldn't get here unless query has ORDER BY */
6501 [ - + ]: 39353 : Assert(parse->sortClause);
6502 : :
3189 6503 : 39353 : *have_postponed_srfs = false; /* default result */
6504 : :
6505 : : /* Inspect tlist and collect per-column information */
3656 6506 : 39353 : ncols = list_length(final_target->exprs);
3642 6507 : 39353 : col_is_srf = (bool *) palloc0(ncols * sizeof(bool));
3656 6508 : 39353 : postpone_col = (bool *) palloc0(ncols * sizeof(bool));
3642 6509 : 39353 : have_srf = have_volatile = have_expensive = have_srf_sortcols = false;
6510 : :
3656 6511 : 39353 : i = 0;
6512 [ + - + + : 237947 : foreach(lc, final_target->exprs)
+ + ]
6513 : : {
6514 : 198594 : Expr *expr = (Expr *) lfirst(lc);
6515 : :
6516 : : /*
6517 : : * If the column has a sortgroupref, assume it has to be evaluated
6518 : : * before sorting. Generally such columns would be ORDER BY, GROUP
6519 : : * BY, etc targets. One exception is columns that were removed from
6520 : : * GROUP BY by remove_useless_groupby_columns() ... but those would
6521 : : * only be Vars anyway. There don't seem to be any cases where it
6522 : : * would be worth the trouble to double-check.
6523 : : */
3562 6524 [ + - + + ]: 198594 : if (get_pathtarget_sortgroupref(final_target, i) == 0)
6525 : : {
6526 : : /*
6527 : : * Check for SRF or volatile functions. Check the SRF case first
6528 : : * because we must know whether we have any postponed SRFs.
6529 : : */
3470 6530 [ + + + + ]: 143635 : if (parse->hasTargetSRFs &&
6531 : 108 : expression_returns_set((Node *) expr))
6532 : : {
6533 : : /* We'll decide below whether these are postponable */
3642 6534 : 48 : col_is_srf[i] = true;
3656 6535 : 48 : have_srf = true;
6536 : : }
6537 [ + + ]: 143479 : else if (contain_volatile_functions((Node *) expr))
6538 : : {
6539 : : /* Unconditionally postpone */
6540 : 124 : postpone_col[i] = true;
6541 : 124 : have_volatile = true;
6542 : : }
6543 : : else
6544 : : {
6545 : : /*
6546 : : * Else check the cost. XXX it's annoying to have to do this
6547 : : * when set_pathtarget_cost_width() just did it. Refactor to
6548 : : * allow sharing the work?
6549 : : */
6550 : : QualCost cost;
6551 : :
6552 : 143355 : cost_qual_eval_node(&cost, (Node *) expr, root);
6553 : :
6554 : : /*
6555 : : * We arbitrarily define "expensive" as "more than 10X
6556 : : * cpu_operator_cost". Note this will take in any PL function
6557 : : * with default cost.
6558 : : */
6559 [ + + ]: 143355 : if (cost.per_tuple > 10 * cpu_operator_cost)
6560 : : {
6561 : 9399 : postpone_col[i] = true;
6562 : 9399 : have_expensive = true;
6563 : : }
6564 : : }
6565 : : }
6566 : : else
6567 : : {
6568 : : /* For sortgroupref cols, just check if any contain SRFs */
3642 6569 [ + + ]: 55067 : if (!have_srf_sortcols &&
3470 6570 [ + + + + ]: 55222 : parse->hasTargetSRFs &&
3642 6571 : 167 : expression_returns_set((Node *) expr))
6572 : 74 : have_srf_sortcols = true;
6573 : : }
6574 : :
3656 6575 : 198594 : i++;
6576 : : }
6577 : :
6578 : : /*
6579 : : * We can postpone SRFs if we have some but none are in sortgroupref cols.
6580 : : */
3642 6581 [ + + + + ]: 39353 : postpone_srfs = (have_srf && !have_srf_sortcols);
6582 : :
6583 : : /*
6584 : : * If we don't need a post-sort projection, just return final_target.
6585 : : */
6586 [ + + + + ]: 39353 : if (!(postpone_srfs || have_volatile ||
3656 6587 [ + + ]: 39201 : (have_expensive &&
6588 [ + + + - ]: 5622 : (parse->limitCount || root->tuple_fraction > 0))))
6589 : 39183 : return final_target;
6590 : :
6591 : : /*
6592 : : * Report whether the post-sort projection will contain set-returning
6593 : : * functions. This is important because it affects whether the Sort can
6594 : : * rely on the query's LIMIT (if any) to bound the number of rows it needs
6595 : : * to return.
6596 : : */
3642 6597 : 170 : *have_postponed_srfs = postpone_srfs;
6598 : :
6599 : : /*
6600 : : * Construct the sort-input target, taking all non-postponable columns and
6601 : : * then adding Vars, PlaceHolderVars, Aggrefs, and WindowFuncs found in
6602 : : * the postponable ones.
6603 : : */
3656 6604 : 170 : input_target = create_empty_pathtarget();
6605 : 170 : postponable_cols = NIL;
6606 : :
6607 : 170 : i = 0;
6608 [ + - + + : 1145 : foreach(lc, final_target->exprs)
+ + ]
6609 : : {
6610 : 975 : Expr *expr = (Expr *) lfirst(lc);
6611 : :
3642 6612 [ + + + + : 975 : if (postpone_col[i] || (postpone_srfs && col_is_srf[i]))
+ + ]
3656 6613 : 199 : postponable_cols = lappend(postponable_cols, expr);
6614 : : else
6615 : 776 : add_column_to_pathtarget(input_target, expr,
3189 6616 [ + - ]: 776 : get_pathtarget_sortgroupref(final_target, i));
6617 : :
3656 6618 : 975 : i++;
6619 : : }
6620 : :
6621 : : /*
6622 : : * Pull out all the Vars, Aggrefs, and WindowFuncs mentioned in
6623 : : * postponable columns, and add them to the sort-input target if not
6624 : : * already present. (Some might be there already.) We mustn't
6625 : : * deconstruct Aggrefs or WindowFuncs here, since the projection node
6626 : : * would be unable to recompute them.
6627 : : */
6628 : 170 : postponable_vars = pull_var_clause((Node *) postponable_cols,
6629 : : PVC_INCLUDE_AGGREGATES |
6630 : : PVC_INCLUDE_WINDOWFUNCS |
6631 : : PVC_INCLUDE_PLACEHOLDERS);
6632 : 170 : add_new_columns_to_pathtarget(input_target, postponable_vars);
6633 : :
6634 : : /* clean up cruft */
6635 : 170 : list_free(postponable_vars);
6636 : 170 : list_free(postponable_cols);
6637 : :
6638 : : /* XXX this represents even more redundant cost calculation ... */
6639 : 170 : return set_pathtarget_cost_width(root, input_target);
6640 : : }
6641 : :
6642 : : /*
6643 : : * get_cheapest_fractional_path
6644 : : * Find the cheapest path for retrieving a specified fraction of all
6645 : : * the tuples expected to be returned by the given relation.
6646 : : *
6647 : : * Do not consider parameterized paths. If the caller needs a path for upper
6648 : : * rel, it can't have parameterized paths. If the caller needs an append
6649 : : * subpath, it could become limited by the treatment of similar
6650 : : * parameterization of all the subpaths.
6651 : : *
6652 : : * We interpret tuple_fraction the same way as grouping_planner.
6653 : : *
6654 : : * We assume set_cheapest() has been run on the given rel.
6655 : : */
6656 : : Path *
3660 6657 : 261931 : get_cheapest_fractional_path(RelOptInfo *rel, double tuple_fraction)
6658 : : {
6659 : 261931 : Path *best_path = rel->cheapest_total_path;
6660 : : ListCell *l;
6661 : :
6662 : : /* If all tuples will be retrieved, just return the cheapest-total path */
6663 [ + + ]: 261931 : if (tuple_fraction <= 0.0)
6664 : 257021 : return best_path;
6665 : :
6666 : : /* Convert absolute # of tuples to a fraction; no need to clamp to 0..1 */
3641 6667 [ + + + + ]: 4910 : if (tuple_fraction >= 1.0 && best_path->rows > 0)
3660 6668 : 2118 : tuple_fraction /= best_path->rows;
6669 : :
6670 [ + - + + : 12681 : foreach(l, rel->pathlist)
+ + ]
6671 : : {
6672 : 7771 : Path *path = (Path *) lfirst(l);
6673 : :
370 akorotkov@postgresql 6674 [ + + ]: 7771 : if (path->param_info)
6675 : 100 : continue;
6676 : :
3660 tgl@sss.pgh.pa.us 6677 [ + + + + ]: 10432 : if (path == rel->cheapest_total_path ||
3189 6678 : 2761 : compare_fractional_path_costs(best_path, path, tuple_fraction) <= 0)
3660 6679 : 7414 : continue;
6680 : :
6681 : 257 : best_path = path;
6682 : : }
6683 : :
6684 : 4910 : return best_path;
6685 : : }
6686 : :
6687 : : /*
6688 : : * adjust_paths_for_srfs
6689 : : * Fix up the Paths of the given upperrel to handle tSRFs properly.
6690 : : *
6691 : : * The executor can only handle set-returning functions that appear at the
6692 : : * top level of the targetlist of a ProjectSet plan node. If we have any SRFs
6693 : : * that are not at top level, we need to split up the evaluation into multiple
6694 : : * plan levels in which each level satisfies this constraint. This function
6695 : : * modifies each Path of an upperrel that (might) compute any SRFs in its
6696 : : * output tlist to insert appropriate projection steps.
6697 : : *
6698 : : * The given targets and targets_contain_srfs lists are from
6699 : : * split_pathtarget_at_srfs(). We assume the existing Paths emit the first
6700 : : * target in targets.
6701 : : */
6702 : : static void
3343 andres@anarazel.de 6703 : 6878 : adjust_paths_for_srfs(PlannerInfo *root, RelOptInfo *rel,
6704 : : List *targets, List *targets_contain_srfs)
6705 : : {
6706 : : ListCell *lc;
6707 : :
6708 [ - + ]: 6878 : Assert(list_length(targets) == list_length(targets_contain_srfs));
6709 [ - + ]: 6878 : Assert(!linitial_int(targets_contain_srfs));
6710 : :
6711 : : /* If no SRFs appear at this plan level, nothing to do */
6712 [ + + ]: 6878 : if (list_length(targets) == 1)
6713 : 359 : return;
6714 : :
6715 : : /*
6716 : : * Stack SRF-evaluation nodes atop each path for the rel.
6717 : : *
6718 : : * In principle we should re-run set_cheapest() here to identify the
6719 : : * cheapest path, but it seems unlikely that adding the same tlist eval
6720 : : * costs to all the paths would change that, so we don't bother. Instead,
6721 : : * just assume that the cheapest-startup and cheapest-total paths remain
6722 : : * so. (There should be no parameterized paths anymore, so we needn't
6723 : : * worry about updating cheapest_parameterized_paths.)
6724 : : */
6725 [ + - + + : 13057 : foreach(lc, rel->pathlist)
+ + ]
6726 : : {
6727 : 6538 : Path *subpath = (Path *) lfirst(lc);
6728 : 6538 : Path *newpath = subpath;
6729 : : ListCell *lc1,
6730 : : *lc2;
6731 : :
6732 [ - + ]: 6538 : Assert(subpath->param_info == NULL);
6733 [ + - + + : 20218 : forboth(lc1, targets, lc2, targets_contain_srfs)
+ - + + +
+ + - +
+ ]
6734 : : {
3113 tgl@sss.pgh.pa.us 6735 : 13680 : PathTarget *thistarget = lfirst_node(PathTarget, lc1);
3343 andres@anarazel.de 6736 : 13680 : bool contains_srfs = (bool) lfirst_int(lc2);
6737 : :
6738 : : /* If this level doesn't contain SRFs, do regular projection */
6739 [ + + ]: 13680 : if (contains_srfs)
6740 : 6568 : newpath = (Path *) create_set_projection_path(root,
6741 : : rel,
6742 : : newpath,
6743 : : thistarget);
6744 : : else
6745 : 7112 : newpath = (Path *) apply_projection_to_path(root,
6746 : : rel,
6747 : : newpath,
6748 : : thistarget);
6749 : : }
6750 : 6538 : lfirst(lc) = newpath;
6751 [ + + ]: 6538 : if (subpath == rel->cheapest_startup_path)
6752 : 207 : rel->cheapest_startup_path = newpath;
6753 [ + + ]: 6538 : if (subpath == rel->cheapest_total_path)
6754 : 207 : rel->cheapest_total_path = newpath;
6755 : : }
6756 : :
6757 : : /* Likewise for partial paths, if any */
2970 rhaas@postgresql.org 6758 [ + + + + : 6528 : foreach(lc, rel->partial_pathlist)
+ + ]
6759 : : {
6760 : 9 : Path *subpath = (Path *) lfirst(lc);
6761 : 9 : Path *newpath = subpath;
6762 : : ListCell *lc1,
6763 : : *lc2;
6764 : :
6765 [ - + ]: 9 : Assert(subpath->param_info == NULL);
6766 [ + - + + : 36 : forboth(lc1, targets, lc2, targets_contain_srfs)
+ - + + +
+ + - +
+ ]
6767 : : {
6768 : 27 : PathTarget *thistarget = lfirst_node(PathTarget, lc1);
6769 : 27 : bool contains_srfs = (bool) lfirst_int(lc2);
6770 : :
6771 : : /* If this level doesn't contain SRFs, do regular projection */
6772 [ + + ]: 27 : if (contains_srfs)
6773 : 9 : newpath = (Path *) create_set_projection_path(root,
6774 : : rel,
6775 : : newpath,
6776 : : thistarget);
6777 : : else
6778 : : {
6779 : : /* avoid apply_projection_to_path, in case of multiple refs */
6780 : 18 : newpath = (Path *) create_projection_path(root,
6781 : : rel,
6782 : : newpath,
6783 : : thistarget);
6784 : : }
6785 : : }
6786 : 9 : lfirst(lc) = newpath;
6787 : : }
6788 : : }
6789 : :
6790 : : /*
6791 : : * expression_planner
6792 : : * Perform planner's transformations on a standalone expression.
6793 : : *
6794 : : * Various utility commands need to evaluate expressions that are not part
6795 : : * of a plannable query. They can do so using the executor's regular
6796 : : * expression-execution machinery, but first the expression has to be fed
6797 : : * through here to transform it from parser output to something executable.
6798 : : *
6799 : : * Currently, we disallow sublinks in standalone expressions, so there's no
6800 : : * real "planning" involved here. (That might not always be true though.)
6801 : : * What we must do is run eval_const_expressions to ensure that any function
6802 : : * calls are converted to positional notation and function default arguments
6803 : : * get inserted. The fact that constant subexpressions get simplified is a
6804 : : * side-effect that is useful when the expression will get evaluated more than
6805 : : * once. Also, we must fix operator function IDs.
6806 : : *
6807 : : * This does not return any information about dependencies of the expression.
6808 : : * Hence callers should use the results only for the duration of the current
6809 : : * query. Callers that would like to cache the results for longer should use
6810 : : * expression_planner_with_deps, probably via the plancache.
6811 : : *
6812 : : * Note: this must not make any damaging changes to the passed-in expression
6813 : : * tree. (It would actually be okay to apply fix_opfuncids to it, but since
6814 : : * we first do an expression_tree_mutator-based walk, what is returned will
6815 : : * be a new node tree.) The result is constructed in the current memory
6816 : : * context; beware that this can leak a lot of additional stuff there, too.
6817 : : */
6818 : : Expr *
6819 : 122821 : expression_planner(Expr *expr)
6820 : : {
6821 : : Node *result;
6822 : :
6823 : : /*
6824 : : * Convert named-argument function calls, insert default arguments and
6825 : : * simplify constant subexprs
6826 : : */
6827 : 122821 : result = eval_const_expressions(NULL, (Node *) expr);
6828 : :
6829 : : /* Fill in opfuncid values if missing */
6830 : 122812 : fix_opfuncids(result);
6831 : :
6832 : 122812 : return (Expr *) result;
6833 : : }
6834 : :
6835 : : /*
6836 : : * expression_planner_with_deps
6837 : : * Perform planner's transformations on a standalone expression,
6838 : : * returning expression dependency information along with the result.
6839 : : *
6840 : : * This is identical to expression_planner() except that it also returns
6841 : : * information about possible dependencies of the expression, ie identities of
6842 : : * objects whose definitions affect the result. As in a PlannedStmt, these
6843 : : * are expressed as a list of relation Oids and a list of PlanInvalItems.
6844 : : */
6845 : : Expr *
2649 tgl@sss.pgh.pa.us 6846 : 189 : expression_planner_with_deps(Expr *expr,
6847 : : List **relationOids,
6848 : : List **invalItems)
6849 : : {
6850 : : Node *result;
6851 : : PlannerGlobal glob;
6852 : : PlannerInfo root;
6853 : :
6854 : : /* Make up dummy planner state so we can use setrefs machinery */
6855 [ + - + - : 5481 : MemSet(&glob, 0, sizeof(glob));
+ - + - +
+ ]
6856 : 189 : glob.type = T_PlannerGlobal;
6857 : 189 : glob.relationOids = NIL;
6858 : 189 : glob.invalItems = NIL;
6859 : :
6860 [ + - + - : 17577 : MemSet(&root, 0, sizeof(root));
+ - + - +
+ ]
6861 : 189 : root.type = T_PlannerInfo;
6862 : 189 : root.glob = &glob;
6863 : :
6864 : : /*
6865 : : * Convert named-argument function calls, insert default arguments and
6866 : : * simplify constant subexprs. Collect identities of inlined functions
6867 : : * and elided domains, too.
6868 : : */
6869 : 189 : result = eval_const_expressions(&root, (Node *) expr);
6870 : :
6871 : : /* Fill in opfuncid values if missing */
6872 : 189 : fix_opfuncids(result);
6873 : :
6874 : : /*
6875 : : * Now walk the finished expression to find anything else we ought to
6876 : : * record as an expression dependency.
6877 : : */
6878 : 189 : (void) extract_query_dependencies_walker(result, &root);
6879 : :
6880 : 189 : *relationOids = glob.relationOids;
6881 : 189 : *invalItems = glob.invalItems;
6882 : :
6883 : 189 : return (Expr *) result;
6884 : : }
6885 : :
6886 : :
6887 : : /*
6888 : : * plan_cluster_use_sort
6889 : : * Use the planner to decide how CLUSTER should implement sorting
6890 : : *
6891 : : * tableOid is the OID of a table to be clustered on its index indexOid
6892 : : * (which is already known to be a btree index). Decide whether it's
6893 : : * cheaper to do an indexscan or a seqscan-plus-sort to execute the CLUSTER.
6894 : : * Return true to use sorting, false to use an indexscan.
6895 : : *
6896 : : * Note: caller had better already hold some type of lock on the table.
6897 : : */
6898 : : bool
2970 rhaas@postgresql.org 6899 : 109 : plan_cluster_use_sort(Oid tableOid, Oid indexOid)
6900 : : {
6901 : : PlannerInfo *root;
6902 : : Query *query;
6903 : : PlannerGlobal *glob;
6904 : : RangeTblEntry *rte;
6905 : : RelOptInfo *rel;
6906 : : IndexOptInfo *indexInfo;
6907 : : QualCost indexExprCost;
6908 : : Cost comparisonCost;
6909 : : Path *seqScanPath;
6910 : : Path seqScanAndSortPath;
6911 : : IndexPath *indexScanPath;
6912 : : ListCell *lc;
6913 : :
6914 : : /* We can short-circuit the cost comparison if indexscans are disabled */
6915 [ + + ]: 109 : if (!enable_indexscan)
6916 : 15 : return true; /* use sort */
6917 : :
6918 : : /* Set up mostly-dummy planner state */
6919 : 94 : query = makeNode(Query);
6920 : 94 : query->commandType = CMD_SELECT;
6921 : :
6922 : 94 : glob = makeNode(PlannerGlobal);
6923 : :
6924 : 94 : root = makeNode(PlannerInfo);
6925 : 94 : root->parse = query;
6926 : 94 : root->glob = glob;
6927 : 94 : root->query_level = 1;
6928 : 94 : root->planner_cxt = CurrentMemoryContext;
6929 : 94 : root->wt_param_id = -1;
1140 tgl@sss.pgh.pa.us 6930 : 94 : root->join_domains = list_make1(makeNode(JoinDomain));
6931 : :
6932 : : /* Build a minimal RTE for the rel */
2970 rhaas@postgresql.org 6933 : 94 : rte = makeNode(RangeTblEntry);
6934 : 94 : rte->rtekind = RTE_RELATION;
6935 : 94 : rte->relid = tableOid;
6936 : 94 : rte->relkind = RELKIND_RELATION; /* Don't be too picky. */
2723 tgl@sss.pgh.pa.us 6937 : 94 : rte->rellockmode = AccessShareLock;
2970 rhaas@postgresql.org 6938 : 94 : rte->lateral = false;
6939 : 94 : rte->inh = false;
6940 : 94 : rte->inFromCl = true;
6941 : 94 : query->rtable = list_make1(rte);
1195 alvherre@alvh.no-ip. 6942 : 94 : addRTEPermissionInfo(&query->rteperminfos, rte);
6943 : :
6944 : : /* Set up RTE/RelOptInfo arrays */
2970 rhaas@postgresql.org 6945 : 94 : setup_simple_rel_arrays(root);
6946 : :
6947 : : /* Build RelOptInfo */
6948 : 94 : rel = build_simple_rel(root, 1, NULL);
6949 : :
6950 : : /* Locate IndexOptInfo for the target index */
6951 : 94 : indexInfo = NULL;
6952 [ + - + - : 119 : foreach(lc, rel->indexlist)
+ - ]
6953 : : {
6954 : 119 : indexInfo = lfirst_node(IndexOptInfo, lc);
6955 [ + + ]: 119 : if (indexInfo->indexoid == indexOid)
6956 : 94 : break;
6957 : : }
6958 : :
6959 : : /*
6960 : : * It's possible that get_relation_info did not generate an IndexOptInfo
6961 : : * for the desired index; this could happen if it's not yet reached its
6962 : : * indcheckxmin usability horizon, or if it's a system index and we're
6963 : : * ignoring system indexes. In such cases we should tell CLUSTER to not
6964 : : * trust the index contents but use seqscan-and-sort.
6965 : : */
6966 [ - + ]: 94 : if (lc == NULL) /* not in the list? */
2970 rhaas@postgresql.org 6967 :UBC 0 : return true; /* use sort */
6968 : :
6969 : : /*
6970 : : * Rather than doing all the pushups that would be needed to use
6971 : : * set_baserel_size_estimates, just do a quick hack for rows and width.
6972 : : */
2970 rhaas@postgresql.org 6973 :CBC 94 : rel->rows = rel->tuples;
6974 : 94 : rel->reltarget->width = get_relation_data_width(tableOid, NULL);
6975 : :
6976 : 94 : root->total_table_pages = rel->pages;
6977 : :
6978 : : /*
6979 : : * Determine eval cost of the index expressions, if any. We need to
6980 : : * charge twice that amount for each tuple comparison that happens during
6981 : : * the sort, since tuplesort.c will have to re-evaluate the index
6982 : : * expressions each time. (XXX that's pretty inefficient...)
6983 : : */
6984 : 94 : cost_qual_eval(&indexExprCost, indexInfo->indexprs, root);
6985 : 94 : comparisonCost = 2.0 * (indexExprCost.startup + indexExprCost.per_tuple);
6986 : :
6987 : : /* Estimate the cost of seq scan + sort */
6988 : 94 : seqScanPath = create_seqscan_path(root, rel, NULL, 0);
6989 : 94 : cost_sort(&seqScanAndSortPath, root, NIL,
6990 : : seqScanPath->disabled_nodes,
6991 : 94 : seqScanPath->total_cost, rel->tuples, rel->reltarget->width,
6992 : : comparisonCost, maintenance_work_mem, -1.0);
6993 : :
6994 : : /* Estimate the cost of index scan */
6995 : 94 : indexScanPath = create_index_path(root, indexInfo,
6996 : : NIL, NIL, NIL, NIL,
6997 : : ForwardScanDirection, false,
6998 : : NULL, 1.0, false);
6999 : :
7000 : 94 : return (seqScanAndSortPath.total_cost < indexScanPath->path.total_cost);
7001 : : }
7002 : :
7003 : : /*
7004 : : * plan_create_index_workers
7005 : : * Use the planner to decide how many parallel worker processes
7006 : : * CREATE INDEX should request for use
7007 : : *
7008 : : * tableOid is the table on which the index is to be built. indexOid is the
7009 : : * OID of an index to be created or reindexed (which must be an index with
7010 : : * support for parallel builds - currently btree, GIN, or BRIN).
7011 : : *
7012 : : * Return value is the number of parallel worker processes to request. It
7013 : : * may be unsafe to proceed if this is 0. Note that this does not include the
7014 : : * leader participating as a worker (value is always a number of parallel
7015 : : * worker processes).
7016 : : *
7017 : : * Note: caller had better already hold some type of lock on the table and
7018 : : * index.
7019 : : */
7020 : : int
2963 7021 : 18423 : plan_create_index_workers(Oid tableOid, Oid indexOid)
7022 : : {
7023 : : PlannerInfo *root;
7024 : : Query *query;
7025 : : PlannerGlobal *glob;
7026 : : RangeTblEntry *rte;
7027 : : Relation heap;
7028 : : Relation index;
7029 : : RelOptInfo *rel;
7030 : : int parallel_workers;
7031 : : BlockNumber heap_blocks;
7032 : : double reltuples;
7033 : : double allvisfrac;
7034 : :
7035 : : /*
7036 : : * We don't allow performing parallel operation in standalone backend or
7037 : : * when parallelism is disabled.
7038 : : */
1931 tgl@sss.pgh.pa.us 7039 [ + + + + ]: 18423 : if (!IsUnderPostmaster || max_parallel_maintenance_workers == 0)
2963 rhaas@postgresql.org 7040 : 257 : return 0;
7041 : :
7042 : : /* Set up largely-dummy planner state */
7043 : 18166 : query = makeNode(Query);
7044 : 18166 : query->commandType = CMD_SELECT;
7045 : :
7046 : 18166 : glob = makeNode(PlannerGlobal);
7047 : :
7048 : 18166 : root = makeNode(PlannerInfo);
7049 : 18166 : root->parse = query;
7050 : 18166 : root->glob = glob;
7051 : 18166 : root->query_level = 1;
7052 : 18166 : root->planner_cxt = CurrentMemoryContext;
7053 : 18166 : root->wt_param_id = -1;
1140 tgl@sss.pgh.pa.us 7054 : 18166 : root->join_domains = list_make1(makeNode(JoinDomain));
7055 : :
7056 : : /*
7057 : : * Build a minimal RTE.
7058 : : *
7059 : : * Mark the RTE with inh = true. This is a kludge to prevent
7060 : : * get_relation_info() from fetching index info, which is necessary
7061 : : * because it does not expect that any IndexOptInfo is currently
7062 : : * undergoing REINDEX.
7063 : : */
2963 rhaas@postgresql.org 7064 : 18166 : rte = makeNode(RangeTblEntry);
7065 : 18166 : rte->rtekind = RTE_RELATION;
7066 : 18166 : rte->relid = tableOid;
7067 : 18166 : rte->relkind = RELKIND_RELATION; /* Don't be too picky. */
2723 tgl@sss.pgh.pa.us 7068 : 18166 : rte->rellockmode = AccessShareLock;
2963 rhaas@postgresql.org 7069 : 18166 : rte->lateral = false;
7070 : 18166 : rte->inh = true;
7071 : 18166 : rte->inFromCl = true;
7072 : 18166 : query->rtable = list_make1(rte);
1195 alvherre@alvh.no-ip. 7073 : 18166 : addRTEPermissionInfo(&query->rteperminfos, rte);
7074 : :
7075 : : /* Set up RTE/RelOptInfo arrays */
2963 rhaas@postgresql.org 7076 : 18166 : setup_simple_rel_arrays(root);
7077 : :
7078 : : /* Build RelOptInfo */
7079 : 18166 : rel = build_simple_rel(root, 1, NULL);
7080 : :
7081 : : /* Rels are assumed already locked by the caller */
2610 andres@anarazel.de 7082 : 18166 : heap = table_open(tableOid, NoLock);
2963 rhaas@postgresql.org 7083 : 18166 : index = index_open(indexOid, NoLock);
7084 : :
7085 : : /*
7086 : : * Determine if it's safe to proceed.
7087 : : *
7088 : : * Currently, parallel workers can't access the leader's temporary tables.
7089 : : * Furthermore, any index predicate or index expressions must be parallel
7090 : : * safe.
7091 : : */
7092 [ + + ]: 18166 : if (heap->rd_rel->relpersistence == RELPERSISTENCE_TEMP ||
738 michael@paquier.xyz 7093 [ + + ]: 17123 : !is_parallel_safe(root, (Node *) RelationGetIndexExpressions(index)) ||
7094 [ - + ]: 17053 : !is_parallel_safe(root, (Node *) RelationGetIndexPredicate(index)))
7095 : : {
2963 rhaas@postgresql.org 7096 : 1113 : parallel_workers = 0;
7097 : 1113 : goto done;
7098 : : }
7099 : :
7100 : : /*
7101 : : * If parallel_workers storage parameter is set for the table, accept that
7102 : : * as the number of parallel worker processes to launch (though still cap
7103 : : * at max_parallel_maintenance_workers). Note that we deliberately do not
7104 : : * consider any other factor when parallel_workers is set. (e.g., memory
7105 : : * use by workers.)
7106 : : */
7107 [ + + ]: 17053 : if (rel->rel_parallel_workers != -1)
7108 : : {
7109 : 50 : parallel_workers = Min(rel->rel_parallel_workers,
7110 : : max_parallel_maintenance_workers);
7111 : 50 : goto done;
7112 : : }
7113 : :
7114 : : /*
7115 : : * Estimate heap relation size ourselves, since rel->pages cannot be
7116 : : * trusted (heap RTE was marked as inheritance parent)
7117 : : */
7118 : 17003 : estimate_rel_size(heap, NULL, &heap_blocks, &reltuples, &allvisfrac);
7119 : :
7120 : : /*
7121 : : * Determine number of workers to scan the heap relation using generic
7122 : : * model
7123 : : */
7124 : 17003 : parallel_workers = compute_parallel_worker(rel, heap_blocks, -1,
7125 : : max_parallel_maintenance_workers);
7126 : :
7127 : : /*
7128 : : * Cap workers based on available maintenance_work_mem as needed.
7129 : : *
7130 : : * Note that each tuplesort participant receives an even share of the
7131 : : * total maintenance_work_mem budget. Aim to leave participants
7132 : : * (including the leader as a participant) with no less than 32MB of
7133 : : * memory. This leaves cases where maintenance_work_mem is set to 64MB
7134 : : * immediately past the threshold of being capable of launching a single
7135 : : * parallel worker to sort.
7136 : : */
7137 [ + + ]: 17086 : while (parallel_workers > 0 &&
408 tgl@sss.pgh.pa.us 7138 [ + + ]: 167 : maintenance_work_mem / (parallel_workers + 1) < 32 * 1024)
2963 rhaas@postgresql.org 7139 : 83 : parallel_workers--;
7140 : :
7141 : 17003 : done:
7142 : 18166 : index_close(index, NoLock);
2610 andres@anarazel.de 7143 : 18166 : table_close(heap, NoLock);
7144 : :
2963 rhaas@postgresql.org 7145 : 18166 : return parallel_workers;
7146 : : }
7147 : :
7148 : : /*
7149 : : * add_paths_to_grouping_rel
7150 : : *
7151 : : * Add non-partial paths to grouping relation.
7152 : : */
7153 : : static void
2970 7154 : 24150 : add_paths_to_grouping_rel(PlannerInfo *root, RelOptInfo *input_rel,
7155 : : RelOptInfo *grouped_rel,
7156 : : RelOptInfo *partially_grouped_rel,
7157 : : const AggClauseCosts *agg_costs,
7158 : : grouping_sets_data *gd,
7159 : : GroupPathExtraData *extra)
7160 : : {
7161 : 24150 : Query *parse = root->parse;
7162 : 24150 : Path *cheapest_path = input_rel->cheapest_total_path;
158 rguo@postgresql.org 7163 :GNC 24150 : Path *cheapest_partially_grouped_path = NULL;
7164 : : ListCell *lc;
2915 rhaas@postgresql.org 7165 :CBC 24150 : bool can_hash = (extra->flags & GROUPING_CAN_USE_HASH) != 0;
7166 : 24150 : bool can_sort = (extra->flags & GROUPING_CAN_USE_SORT) != 0;
7167 : 24150 : List *havingQual = (List *) extra->havingQual;
7168 : 24150 : AggClauseCosts *agg_final_costs = &extra->agg_final_costs;
158 rguo@postgresql.org 7169 :GNC 24150 : double dNumGroups = 0;
7170 : 24150 : double dNumFinalGroups = 0;
7171 : :
7172 : : /*
7173 : : * Estimate number of groups for non-split aggregation.
7174 : : */
7175 : 24150 : dNumGroups = get_number_of_groups(root,
7176 : : cheapest_path->rows,
7177 : : gd,
7178 : : extra->targetList);
7179 : :
7180 [ + + + - ]: 24150 : if (partially_grouped_rel && partially_grouped_rel->pathlist)
7181 : : {
7182 : 1501 : cheapest_partially_grouped_path =
7183 : : partially_grouped_rel->cheapest_total_path;
7184 : :
7185 : : /*
7186 : : * Estimate number of groups for final phase of partial aggregation.
7187 : : */
7188 : : dNumFinalGroups =
7189 : 1501 : get_number_of_groups(root,
7190 : : cheapest_partially_grouped_path->rows,
7191 : : gd,
7192 : : extra->targetList);
7193 : : }
7194 : :
2970 rhaas@postgresql.org 7195 [ + + ]:CBC 24150 : if (can_sort)
7196 : : {
7197 : : /*
7198 : : * Use any available suitably-sorted path as input, and also consider
7199 : : * sorting the cheapest-total path and incremental sort on any paths
7200 : : * with presorted keys.
7201 : : */
7202 [ + - + + : 50014 : foreach(lc, input_rel->pathlist)
+ + ]
7203 : : {
7204 : : ListCell *lc2;
7205 : 25867 : Path *path = (Path *) lfirst(lc);
784 akorotkov@postgresql 7206 : 25867 : Path *path_save = path;
7207 : 25867 : List *pathkey_orderings = NIL;
7208 : :
7209 : : /* generate alternative group orderings that might be useful */
7210 : 25867 : pathkey_orderings = get_useful_group_keys_orderings(root, path);
7211 : :
7212 [ - + ]: 25867 : Assert(list_length(pathkey_orderings) > 0);
7213 : :
7214 [ + - + + : 51806 : foreach(lc2, pathkey_orderings)
+ + ]
7215 : : {
647 7216 : 25939 : GroupByOrdering *info = (GroupByOrdering *) lfirst(lc2);
7217 : :
7218 : : /* restore the path (we replace it in the loop) */
784 7219 : 25939 : path = path_save;
7220 : :
7221 : 25939 : path = make_ordered_path(root,
7222 : : grouped_rel,
7223 : : path,
7224 : : cheapest_path,
7225 : : info->pathkeys,
7226 : : -1.0);
7227 [ + + ]: 25939 : if (path == NULL)
7228 : 193 : continue;
7229 : :
7230 : : /* Now decide what to stick atop it */
7231 [ + + ]: 25746 : if (parse->groupingSets)
7232 : : {
7233 : 540 : consider_groupingsets_paths(root, grouped_rel,
7234 : : path, true, can_hash,
7235 : : gd, agg_costs, dNumGroups);
7236 : : }
7237 [ + + ]: 25206 : else if (parse->hasAggs)
7238 : : {
7239 : : /*
7240 : : * We have aggregation, possibly with plain GROUP BY. Make
7241 : : * an AggPath.
7242 : : */
1259 tgl@sss.pgh.pa.us 7243 : 24802 : add_path(grouped_rel, (Path *)
7244 : 24802 : create_agg_path(root,
7245 : : grouped_rel,
7246 : : path,
7247 : 24802 : grouped_rel->reltarget,
7248 : 24802 : parse->groupClause ? AGG_SORTED : AGG_PLAIN,
7249 : : AGGSPLIT_SIMPLE,
7250 : : info->clauses,
7251 : : havingQual,
7252 : : agg_costs,
7253 : : dNumGroups));
7254 : : }
784 akorotkov@postgresql 7255 [ + - ]: 404 : else if (parse->groupClause)
7256 : : {
7257 : : /*
7258 : : * We have GROUP BY without aggregation or grouping sets.
7259 : : * Make a GroupPath.
7260 : : */
1259 tgl@sss.pgh.pa.us 7261 : 404 : add_path(grouped_rel, (Path *)
7262 : 404 : create_group_path(root,
7263 : : grouped_rel,
7264 : : path,
7265 : : info->clauses,
7266 : : havingQual,
7267 : : dNumGroups));
7268 : : }
7269 : : else
7270 : : {
7271 : : /* Other cases should have been handled above */
784 akorotkov@postgresql 7272 :UBC 0 : Assert(false);
7273 : : }
7274 : : }
7275 : : }
7276 : :
7277 : : /*
7278 : : * Instead of operating directly on the input relation, we can
7279 : : * consider finalizing a partially aggregated path.
7280 : : */
784 akorotkov@postgresql 7281 [ + + ]:CBC 24147 : if (partially_grouped_rel != NULL)
7282 : : {
7283 [ + - + + : 3846 : foreach(lc, partially_grouped_rel->pathlist)
+ + ]
7284 : : {
7285 : : ListCell *lc2;
7286 : 2345 : Path *path = (Path *) lfirst(lc);
7287 : 2345 : Path *path_save = path;
7288 : 2345 : List *pathkey_orderings = NIL;
7289 : :
7290 : : /* generate alternative group orderings that might be useful */
7291 : 2345 : pathkey_orderings = get_useful_group_keys_orderings(root, path);
7292 : :
7293 [ - + ]: 2345 : Assert(list_length(pathkey_orderings) > 0);
7294 : :
7295 : : /* process all potentially interesting grouping reorderings */
7296 [ + - + + : 4690 : foreach(lc2, pathkey_orderings)
+ + ]
7297 : : {
647 7298 : 2345 : GroupByOrdering *info = (GroupByOrdering *) lfirst(lc2);
7299 : :
7300 : : /* restore the path (we replace it in the loop) */
784 7301 : 2345 : path = path_save;
7302 : :
7303 : 2345 : path = make_ordered_path(root,
7304 : : grouped_rel,
7305 : : path,
7306 : : cheapest_partially_grouped_path,
7307 : : info->pathkeys,
7308 : : -1.0);
7309 : :
7310 [ + + ]: 2345 : if (path == NULL)
7311 : 102 : continue;
7312 : :
7313 [ + + ]: 2243 : if (parse->hasAggs)
7314 : 2119 : add_path(grouped_rel, (Path *)
7315 : 2119 : create_agg_path(root,
7316 : : grouped_rel,
7317 : : path,
7318 : 2119 : grouped_rel->reltarget,
7319 : 2119 : parse->groupClause ? AGG_SORTED : AGG_PLAIN,
7320 : : AGGSPLIT_FINAL_DESERIAL,
7321 : : info->clauses,
7322 : : havingQual,
7323 : : agg_final_costs,
7324 : : dNumFinalGroups));
7325 : : else
7326 : 124 : add_path(grouped_rel, (Path *)
7327 : 124 : create_group_path(root,
7328 : : grouped_rel,
7329 : : path,
7330 : : info->clauses,
7331 : : havingQual,
7332 : : dNumFinalGroups));
7333 : :
7334 : : }
7335 : : }
7336 : : }
7337 : : }
7338 : :
2970 rhaas@postgresql.org 7339 [ + + ]: 24150 : if (can_hash)
7340 : : {
7341 [ + + ]: 3029 : if (parse->groupingSets)
7342 : : {
7343 : : /*
7344 : : * Try for a hash-only groupingsets path over unsorted input.
7345 : : */
7346 : 459 : consider_groupingsets_paths(root, grouped_rel,
7347 : : cheapest_path, false, true,
7348 : : gd, agg_costs, dNumGroups);
7349 : : }
7350 : : else
7351 : : {
7352 : : /*
7353 : : * Generate a HashAgg Path. We just need an Agg over the
7354 : : * cheapest-total input path, since input order won't matter.
7355 : : */
2057 pg@bowt.ie 7356 : 2570 : add_path(grouped_rel, (Path *)
7357 : 2570 : create_agg_path(root, grouped_rel,
7358 : : cheapest_path,
7359 : 2570 : grouped_rel->reltarget,
7360 : : AGG_HASHED,
7361 : : AGGSPLIT_SIMPLE,
7362 : : root->processed_groupClause,
7363 : : havingQual,
7364 : : agg_costs,
7365 : : dNumGroups));
7366 : : }
7367 : :
7368 : : /*
7369 : : * Generate a Finalize HashAgg Path atop of the cheapest partially
7370 : : * grouped path, assuming there is one
7371 : : */
2917 rhaas@postgresql.org 7372 [ + + + - ]: 3029 : if (partially_grouped_rel && partially_grouped_rel->pathlist)
7373 : : {
2057 pg@bowt.ie 7374 : 724 : add_path(grouped_rel, (Path *)
7375 : 724 : create_agg_path(root,
7376 : : grouped_rel,
7377 : : cheapest_partially_grouped_path,
7378 : 724 : grouped_rel->reltarget,
7379 : : AGG_HASHED,
7380 : : AGGSPLIT_FINAL_DESERIAL,
7381 : : root->processed_groupClause,
7382 : : havingQual,
7383 : : agg_final_costs,
7384 : : dNumFinalGroups));
7385 : : }
7386 : : }
7387 : :
7388 : : /*
7389 : : * When partitionwise aggregate is used, we might have fully aggregated
7390 : : * paths in the partial pathlist, because add_paths_to_append_rel() will
7391 : : * consider a path for grouped_rel consisting of a Parallel Append of
7392 : : * non-partial paths from each child.
7393 : : */
2915 rhaas@postgresql.org 7394 [ + + ]: 24150 : if (grouped_rel->partial_pathlist != NIL)
7395 : 159 : gather_grouping_paths(root, grouped_rel);
5638 tgl@sss.pgh.pa.us 7396 : 24150 : }
7397 : :
7398 : : /*
7399 : : * create_partial_grouping_paths
7400 : : *
7401 : : * Create a new upper relation representing the result of partial aggregation
7402 : : * and populate it with appropriate paths. Note that we don't finalize the
7403 : : * lists of paths here, so the caller can add additional partial or non-partial
7404 : : * paths and must afterward call gather_grouping_paths and set_cheapest on
7405 : : * the returned upper relation.
7406 : : *
7407 : : * All paths for this new upper relation -- both partial and non-partial --
7408 : : * have been partially aggregated but require a subsequent FinalizeAggregate
7409 : : * step.
7410 : : *
7411 : : * NB: This function is allowed to return NULL if it determines that there is
7412 : : * no real need to create a new RelOptInfo.
7413 : : */
7414 : : static RelOptInfo *
2917 rhaas@postgresql.org 7415 : 21728 : create_partial_grouping_paths(PlannerInfo *root,
7416 : : RelOptInfo *grouped_rel,
7417 : : RelOptInfo *input_rel,
7418 : : grouping_sets_data *gd,
7419 : : GroupPathExtraData *extra,
7420 : : bool force_rel_creation)
7421 : : {
2970 7422 : 21728 : Query *parse = root->parse;
7423 : : RelOptInfo *partially_grouped_rel;
158 rguo@postgresql.org 7424 :GNC 21728 : RelOptInfo *eager_agg_rel = NULL;
2915 rhaas@postgresql.org 7425 :CBC 21728 : AggClauseCosts *agg_partial_costs = &extra->agg_partial_costs;
7426 : 21728 : AggClauseCosts *agg_final_costs = &extra->agg_final_costs;
7427 : 21728 : Path *cheapest_partial_path = NULL;
7428 : 21728 : Path *cheapest_total_path = NULL;
2970 7429 : 21728 : double dNumPartialGroups = 0;
2915 7430 : 21728 : double dNumPartialPartialGroups = 0;
7431 : : ListCell *lc;
7432 : 21728 : bool can_hash = (extra->flags & GROUPING_CAN_USE_HASH) != 0;
7433 : 21728 : bool can_sort = (extra->flags & GROUPING_CAN_USE_SORT) != 0;
7434 : :
7435 : : /*
7436 : : * Check whether any partially aggregated paths have been generated
7437 : : * through eager aggregation.
7438 : : */
158 rguo@postgresql.org 7439 [ + + ]:GNC 21728 : if (input_rel->grouped_rel &&
7440 [ + - ]: 479 : !IS_DUMMY_REL(input_rel->grouped_rel) &&
7441 [ + + ]: 479 : input_rel->grouped_rel->pathlist != NIL)
7442 : 449 : eager_agg_rel = input_rel->grouped_rel;
7443 : :
7444 : : /*
7445 : : * Consider whether we should generate partially aggregated non-partial
7446 : : * paths. We can only do this if we have a non-partial path, and only if
7447 : : * the parent of the input rel is performing partial partitionwise
7448 : : * aggregation. (Note that extra->patype is the type of partitionwise
7449 : : * aggregation being used at the parent level, not this level.)
7450 : : */
2915 rhaas@postgresql.org 7451 [ + - ]:CBC 21728 : if (input_rel->pathlist != NIL &&
7452 [ + + ]: 21728 : extra->patype == PARTITIONWISE_AGGREGATE_PARTIAL)
7453 : 429 : cheapest_total_path = input_rel->cheapest_total_path;
7454 : :
7455 : : /*
7456 : : * If parallelism is possible for grouped_rel, then we should consider
7457 : : * generating partially-grouped partial paths. However, if the input rel
7458 : : * has no partial paths, then we can't.
7459 : : */
7460 [ + + + + ]: 21728 : if (grouped_rel->consider_parallel && input_rel->partial_pathlist != NIL)
7461 : 1639 : cheapest_partial_path = linitial(input_rel->partial_pathlist);
7462 : :
7463 : : /*
7464 : : * If we can't partially aggregate partial paths, and we can't partially
7465 : : * aggregate non-partial paths, and no partially aggregated paths were
7466 : : * generated by eager aggregation, then don't bother creating the new
7467 : : * RelOptInfo at all, unless the caller specified force_rel_creation.
7468 : : */
7469 [ + + + + ]: 21728 : if (cheapest_total_path == NULL &&
7470 [ + + ]: 19912 : cheapest_partial_path == NULL &&
158 rguo@postgresql.org 7471 :GNC 19847 : eager_agg_rel == NULL &&
2915 rhaas@postgresql.org 7472 [ + + ]:CBC 19847 : !force_rel_creation)
7473 : 19798 : return NULL;
7474 : :
7475 : : /*
7476 : : * Build a new upper relation to represent the result of partially
7477 : : * aggregating the rows from the input relation.
7478 : : */
2917 7479 : 1930 : partially_grouped_rel = fetch_upper_rel(root,
7480 : : UPPERREL_PARTIAL_GROUP_AGG,
7481 : : grouped_rel->relids);
7482 : 1930 : partially_grouped_rel->consider_parallel =
7483 : 1930 : grouped_rel->consider_parallel;
46 rhaas@postgresql.org 7484 :GNC 1930 : partially_grouped_rel->pgs_mask = grouped_rel->pgs_mask;
2915 rhaas@postgresql.org 7485 :CBC 1930 : partially_grouped_rel->reloptkind = grouped_rel->reloptkind;
2917 7486 : 1930 : partially_grouped_rel->serverid = grouped_rel->serverid;
7487 : 1930 : partially_grouped_rel->userid = grouped_rel->userid;
7488 : 1930 : partially_grouped_rel->useridiscurrent = grouped_rel->useridiscurrent;
7489 : 1930 : partially_grouped_rel->fdwroutine = grouped_rel->fdwroutine;
7490 : :
7491 : : /*
7492 : : * Build target list for partial aggregate paths. These paths cannot just
7493 : : * emit the same tlist as regular aggregate paths, because (1) we must
7494 : : * include Vars and Aggrefs needed in HAVING, which might not appear in
7495 : : * the result tlist, and (2) the Aggrefs must be set in partial mode.
7496 : : */
7497 : 1930 : partially_grouped_rel->reltarget =
7498 : 1930 : make_partial_grouping_target(root, grouped_rel->reltarget,
7499 : : extra->havingQual);
7500 : :
2915 7501 [ + + ]: 1930 : if (!extra->partial_costs_set)
7502 : : {
7503 : : /*
7504 : : * Collect statistics about aggregates for estimating costs of
7505 : : * performing aggregation in parallel.
7506 : : */
7507 [ + - + - : 6954 : MemSet(agg_partial_costs, 0, sizeof(AggClauseCosts));
+ - + - +
+ ]
7508 [ + - + - : 6954 : MemSet(agg_final_costs, 0, sizeof(AggClauseCosts));
+ - + - +
+ ]
7509 [ + + ]: 1159 : if (parse->hasAggs)
7510 : : {
7511 : : /* partial phase */
1937 heikki.linnakangas@i 7512 : 1092 : get_agg_clause_costs(root, AGGSPLIT_INITIAL_SERIAL,
7513 : : agg_partial_costs);
7514 : :
7515 : : /* final phase */
7516 : 1092 : get_agg_clause_costs(root, AGGSPLIT_FINAL_DESERIAL,
7517 : : agg_final_costs);
7518 : : }
7519 : :
2915 rhaas@postgresql.org 7520 : 1159 : extra->partial_costs_set = true;
7521 : : }
7522 : :
7523 : : /* Estimate number of partial groups. */
7524 [ + + ]: 1930 : if (cheapest_total_path != NULL)
7525 : : dNumPartialGroups =
7526 : 429 : get_number_of_groups(root,
7527 : : cheapest_total_path->rows,
7528 : : gd,
7529 : : extra->targetList);
7530 [ + + ]: 1930 : if (cheapest_partial_path != NULL)
7531 : : dNumPartialPartialGroups =
7532 : 1639 : get_number_of_groups(root,
7533 : : cheapest_partial_path->rows,
7534 : : gd,
7535 : : extra->targetList);
7536 : :
7537 [ + - + + ]: 1930 : if (can_sort && cheapest_total_path != NULL)
7538 : : {
7539 : : /* This should have been checked previously */
2970 7540 [ + + - + ]: 429 : Assert(parse->hasAggs || parse->groupClause);
7541 : :
7542 : : /*
7543 : : * Use any available suitably-sorted path as input, and also consider
7544 : : * sorting the cheapest partial path.
7545 : : */
2915 7546 [ + - + + : 858 : foreach(lc, input_rel->pathlist)
+ + ]
7547 : : {
7548 : : ListCell *lc2;
7549 : 429 : Path *path = (Path *) lfirst(lc);
784 akorotkov@postgresql 7550 : 429 : Path *path_save = path;
7551 : 429 : List *pathkey_orderings = NIL;
7552 : :
7553 : : /* generate alternative group orderings that might be useful */
7554 : 429 : pathkey_orderings = get_useful_group_keys_orderings(root, path);
7555 : :
7556 [ - + ]: 429 : Assert(list_length(pathkey_orderings) > 0);
7557 : :
7558 : : /* process all potentially interesting grouping reorderings */
7559 [ + - + + : 858 : foreach(lc2, pathkey_orderings)
+ + ]
7560 : : {
647 7561 : 429 : GroupByOrdering *info = (GroupByOrdering *) lfirst(lc2);
7562 : :
7563 : : /* restore the path (we replace it in the loop) */
784 7564 : 429 : path = path_save;
7565 : :
7566 : 429 : path = make_ordered_path(root,
7567 : : partially_grouped_rel,
7568 : : path,
7569 : : cheapest_total_path,
7570 : : info->pathkeys,
7571 : : -1.0);
7572 : :
7573 [ - + ]: 429 : if (path == NULL)
784 akorotkov@postgresql 7574 :UBC 0 : continue;
7575 : :
784 akorotkov@postgresql 7576 [ + + ]:CBC 429 : if (parse->hasAggs)
7577 : 393 : add_path(partially_grouped_rel, (Path *)
7578 : 393 : create_agg_path(root,
7579 : : partially_grouped_rel,
7580 : : path,
7581 : 393 : partially_grouped_rel->reltarget,
7582 : 393 : parse->groupClause ? AGG_SORTED : AGG_PLAIN,
7583 : : AGGSPLIT_INITIAL_SERIAL,
7584 : : info->clauses,
7585 : : NIL,
7586 : : agg_partial_costs,
7587 : : dNumPartialGroups));
7588 : : else
7589 : 36 : add_path(partially_grouped_rel, (Path *)
7590 : 36 : create_group_path(root,
7591 : : partially_grouped_rel,
7592 : : path,
7593 : : info->clauses,
7594 : : NIL,
7595 : : dNumPartialGroups));
7596 : : }
7597 : : }
7598 : : }
7599 : :
2915 rhaas@postgresql.org 7600 [ + - + + ]: 1930 : if (can_sort && cheapest_partial_path != NULL)
7601 : : {
7602 : : /* Similar to above logic, but for partial paths. */
2970 7603 [ + - + + : 3539 : foreach(lc, input_rel->partial_pathlist)
+ + ]
7604 : : {
7605 : : ListCell *lc2;
7606 : 1900 : Path *path = (Path *) lfirst(lc);
784 akorotkov@postgresql 7607 : 1900 : Path *path_save = path;
7608 : 1900 : List *pathkey_orderings = NIL;
7609 : :
7610 : : /* generate alternative group orderings that might be useful */
7611 : 1900 : pathkey_orderings = get_useful_group_keys_orderings(root, path);
7612 : :
7613 [ - + ]: 1900 : Assert(list_length(pathkey_orderings) > 0);
7614 : :
7615 : : /* process all potentially interesting grouping reorderings */
7616 [ + - + + : 3800 : foreach(lc2, pathkey_orderings)
+ + ]
7617 : : {
647 7618 : 1900 : GroupByOrdering *info = (GroupByOrdering *) lfirst(lc2);
7619 : :
7620 : :
7621 : : /* restore the path (we replace it in the loop) */
784 7622 : 1900 : path = path_save;
7623 : :
7624 : 1900 : path = make_ordered_path(root,
7625 : : partially_grouped_rel,
7626 : : path,
7627 : : cheapest_partial_path,
7628 : : info->pathkeys,
7629 : : -1.0);
7630 : :
7631 [ + + ]: 1900 : if (path == NULL)
7632 : 3 : continue;
7633 : :
7634 [ + + ]: 1897 : if (parse->hasAggs)
7635 : 1836 : add_partial_path(partially_grouped_rel, (Path *)
7636 : 1836 : create_agg_path(root,
7637 : : partially_grouped_rel,
7638 : : path,
7639 : 1836 : partially_grouped_rel->reltarget,
7640 : 1836 : parse->groupClause ? AGG_SORTED : AGG_PLAIN,
7641 : : AGGSPLIT_INITIAL_SERIAL,
7642 : : info->clauses,
7643 : : NIL,
7644 : : agg_partial_costs,
7645 : : dNumPartialPartialGroups));
7646 : : else
7647 : 61 : add_partial_path(partially_grouped_rel, (Path *)
7648 : 61 : create_group_path(root,
7649 : : partially_grouped_rel,
7650 : : path,
7651 : : info->clauses,
7652 : : NIL,
7653 : : dNumPartialPartialGroups));
7654 : : }
7655 : : }
7656 : : }
7657 : :
7658 : : /*
7659 : : * Add a partially-grouped HashAgg Path where possible
7660 : : */
2915 rhaas@postgresql.org 7661 [ + + + + ]: 1930 : if (can_hash && cheapest_total_path != NULL)
7662 : : {
7663 : : /* Checked above */
2970 7664 [ + + - + ]: 429 : Assert(parse->hasAggs || parse->groupClause);
7665 : :
2057 pg@bowt.ie 7666 : 429 : add_path(partially_grouped_rel, (Path *)
7667 : 429 : create_agg_path(root,
7668 : : partially_grouped_rel,
7669 : : cheapest_total_path,
7670 : 429 : partially_grouped_rel->reltarget,
7671 : : AGG_HASHED,
7672 : : AGGSPLIT_INITIAL_SERIAL,
7673 : : root->processed_groupClause,
7674 : : NIL,
7675 : : agg_partial_costs,
7676 : : dNumPartialGroups));
7677 : : }
7678 : :
7679 : : /*
7680 : : * Now add a partially-grouped HashAgg partial Path where possible
7681 : : */
2915 rhaas@postgresql.org 7682 [ + + + + ]: 1930 : if (can_hash && cheapest_partial_path != NULL)
7683 : : {
2057 pg@bowt.ie 7684 : 862 : add_partial_path(partially_grouped_rel, (Path *)
7685 : 862 : create_agg_path(root,
7686 : : partially_grouped_rel,
7687 : : cheapest_partial_path,
7688 : 862 : partially_grouped_rel->reltarget,
7689 : : AGG_HASHED,
7690 : : AGGSPLIT_INITIAL_SERIAL,
7691 : : root->processed_groupClause,
7692 : : NIL,
7693 : : agg_partial_costs,
7694 : : dNumPartialPartialGroups));
7695 : : }
7696 : :
7697 : : /*
7698 : : * Add any partially aggregated paths generated by eager aggregation to
7699 : : * the new upper relation after applying projection steps as needed.
7700 : : */
158 rguo@postgresql.org 7701 [ + + ]:GNC 1930 : if (eager_agg_rel)
7702 : : {
7703 : : /* Add the paths */
7704 [ + - + + : 1174 : foreach(lc, eager_agg_rel->pathlist)
+ + ]
7705 : : {
7706 : 725 : Path *path = (Path *) lfirst(lc);
7707 : :
7708 : : /* Shouldn't have any parameterized paths anymore */
7709 [ - + ]: 725 : Assert(path->param_info == NULL);
7710 : :
7711 : 725 : path = (Path *) create_projection_path(root,
7712 : : partially_grouped_rel,
7713 : : path,
7714 : 725 : partially_grouped_rel->reltarget);
7715 : :
7716 : 725 : add_path(partially_grouped_rel, path);
7717 : : }
7718 : :
7719 : : /*
7720 : : * Likewise add the partial paths, but only if parallelism is possible
7721 : : * for partially_grouped_rel.
7722 : : */
7723 [ + + ]: 449 : if (partially_grouped_rel->consider_parallel)
7724 : : {
7725 [ + + + + : 1014 : foreach(lc, eager_agg_rel->partial_pathlist)
+ + ]
7726 : : {
7727 : 606 : Path *path = (Path *) lfirst(lc);
7728 : :
7729 : : /* Shouldn't have any parameterized paths anymore */
7730 [ - + ]: 606 : Assert(path->param_info == NULL);
7731 : :
7732 : 606 : path = (Path *) create_projection_path(root,
7733 : : partially_grouped_rel,
7734 : : path,
7735 : 606 : partially_grouped_rel->reltarget);
7736 : :
7737 : 606 : add_partial_path(partially_grouped_rel, path);
7738 : : }
7739 : : }
7740 : : }
7741 : :
7742 : : /*
7743 : : * If there is an FDW that's responsible for all baserels of the query,
7744 : : * let it consider adding partially grouped ForeignPaths.
7745 : : */
2939 rhaas@postgresql.org 7746 [ + + ]:CBC 1930 : if (partially_grouped_rel->fdwroutine &&
7747 [ + - ]: 3 : partially_grouped_rel->fdwroutine->GetForeignUpperPaths)
7748 : : {
7749 : 3 : FdwRoutine *fdwroutine = partially_grouped_rel->fdwroutine;
7750 : :
7751 : 3 : fdwroutine->GetForeignUpperPaths(root,
7752 : : UPPERREL_PARTIAL_GROUP_AGG,
7753 : : input_rel, partially_grouped_rel,
7754 : : extra);
7755 : : }
7756 : :
2917 7757 : 1930 : return partially_grouped_rel;
7758 : : }
7759 : :
7760 : : /*
7761 : : * make_ordered_path
7762 : : * Return a path ordered by 'pathkeys' based on the given 'path'. May
7763 : : * return NULL if it doesn't make sense to generate an ordered path in
7764 : : * this case.
7765 : : */
7766 : : static Path *
474 rguo@postgresql.org 7767 : 33940 : make_ordered_path(PlannerInfo *root, RelOptInfo *rel, Path *path,
7768 : : Path *cheapest_path, List *pathkeys, double limit_tuples)
7769 : : {
7770 : : bool is_sorted;
7771 : : int presorted_keys;
7772 : :
7773 : 33940 : is_sorted = pathkeys_count_contained_in(pathkeys,
7774 : : path->pathkeys,
7775 : : &presorted_keys);
7776 : :
7777 [ + + ]: 33940 : if (!is_sorted)
7778 : : {
7779 : : /*
7780 : : * Try at least sorting the cheapest path and also try incrementally
7781 : : * sorting any path which is partially sorted already (no need to deal
7782 : : * with paths which have presorted keys when incremental sort is
7783 : : * disabled unless it's the cheapest input path).
7784 : : */
7785 [ + + ]: 8720 : if (path != cheapest_path &&
7786 [ + + + + ]: 1686 : (presorted_keys == 0 || !enable_incremental_sort))
7787 : 753 : return NULL;
7788 : :
7789 : : /*
7790 : : * We've no need to consider both a sort and incremental sort. We'll
7791 : : * just do a sort if there are no presorted keys and an incremental
7792 : : * sort when there are presorted keys.
7793 : : */
7794 [ + + + + ]: 7967 : if (presorted_keys == 0 || !enable_incremental_sort)
7795 : 6947 : path = (Path *) create_sort_path(root,
7796 : : rel,
7797 : : path,
7798 : : pathkeys,
7799 : : limit_tuples);
7800 : : else
7801 : 1020 : path = (Path *) create_incremental_sort_path(root,
7802 : : rel,
7803 : : path,
7804 : : pathkeys,
7805 : : presorted_keys,
7806 : : limit_tuples);
7807 : : }
7808 : :
7809 : 33187 : return path;
7810 : : }
7811 : :
7812 : : /*
7813 : : * Generate Gather and Gather Merge paths for a grouping relation or partial
7814 : : * grouping relation.
7815 : : *
7816 : : * generate_useful_gather_paths does most of the work, but we also consider a
7817 : : * special case: we could try sorting the data by the group_pathkeys and then
7818 : : * applying Gather Merge.
7819 : : *
7820 : : * NB: This function shouldn't be used for anything other than a grouped or
7821 : : * partially grouped relation not only because of the fact that it explicitly
7822 : : * references group_pathkeys but we pass "true" as the third argument to
7823 : : * generate_useful_gather_paths().
7824 : : */
7825 : : static void
2917 rhaas@postgresql.org 7826 : 1546 : gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel)
7827 : : {
7828 : : ListCell *lc;
7829 : : Path *cheapest_partial_path;
7830 : : List *groupby_pathkeys;
7831 : :
7832 : : /*
7833 : : * This occurs after any partial aggregation has taken place, so trim off
7834 : : * any pathkeys added for ORDER BY / DISTINCT aggregates.
7835 : : */
730 drowley@postgresql.o 7836 [ + + ]: 1546 : if (list_length(root->group_pathkeys) > root->num_groupby_pathkeys)
7837 : 9 : groupby_pathkeys = list_copy_head(root->group_pathkeys,
7838 : : root->num_groupby_pathkeys);
7839 : : else
7840 : 1537 : groupby_pathkeys = root->group_pathkeys;
7841 : :
7842 : : /* Try Gather for unordered paths and Gather Merge for ordered ones. */
2168 tomas.vondra@postgre 7843 : 1546 : generate_useful_gather_paths(root, rel, true);
7844 : :
2917 rhaas@postgresql.org 7845 : 1546 : cheapest_partial_path = linitial(rel->partial_pathlist);
7846 : :
7847 : : /* XXX Shouldn't this also consider the group-key-reordering? */
2168 tomas.vondra@postgre 7848 [ + - + + : 3677 : foreach(lc, rel->partial_pathlist)
+ + ]
7849 : : {
7850 : 2131 : Path *path = (Path *) lfirst(lc);
7851 : : bool is_sorted;
7852 : : int presorted_keys;
7853 : : double total_groups;
7854 : :
730 drowley@postgresql.o 7855 : 2131 : is_sorted = pathkeys_count_contained_in(groupby_pathkeys,
7856 : : path->pathkeys,
7857 : : &presorted_keys);
7858 : :
2168 tomas.vondra@postgre 7859 [ + + ]: 2131 : if (is_sorted)
7860 : 1390 : continue;
7861 : :
7862 : : /*
7863 : : * Try at least sorting the cheapest path and also try incrementally
7864 : : * sorting any path which is partially sorted already (no need to deal
7865 : : * with paths which have presorted keys when incremental sort is
7866 : : * disabled unless it's the cheapest input path).
7867 : : */
774 drowley@postgresql.o 7868 [ - + ]: 741 : if (path != cheapest_partial_path &&
774 drowley@postgresql.o 7869 [ # # # # ]:UBC 0 : (presorted_keys == 0 || !enable_incremental_sort))
2168 tomas.vondra@postgre 7870 : 0 : continue;
7871 : :
7872 : : /*
7873 : : * We've no need to consider both a sort and incremental sort. We'll
7874 : : * just do a sort if there are no presorted keys and an incremental
7875 : : * sort when there are presorted keys.
7876 : : */
774 drowley@postgresql.o 7877 [ - + - - ]:CBC 741 : if (presorted_keys == 0 || !enable_incremental_sort)
7878 : 741 : path = (Path *) create_sort_path(root, rel, path,
7879 : : groupby_pathkeys,
7880 : : -1.0);
7881 : : else
774 drowley@postgresql.o 7882 :UBC 0 : path = (Path *) create_incremental_sort_path(root,
7883 : : rel,
7884 : : path,
7885 : : groupby_pathkeys,
7886 : : presorted_keys,
7887 : : -1.0);
600 rguo@postgresql.org 7888 :CBC 741 : total_groups = compute_gather_rows(path);
7889 : : path = (Path *)
2168 tomas.vondra@postgre 7890 : 741 : create_gather_merge_path(root,
7891 : : rel,
7892 : : path,
7893 : 741 : rel->reltarget,
7894 : : groupby_pathkeys,
7895 : : NULL,
7896 : : &total_groups);
7897 : :
7898 : 741 : add_path(rel, path);
7899 : : }
3281 rhaas@postgresql.org 7900 : 1546 : }
7901 : :
7902 : : /*
7903 : : * can_partial_agg
7904 : : *
7905 : : * Determines whether or not partial grouping and/or aggregation is possible.
7906 : : * Returns true when possible, false otherwise.
7907 : : */
7908 : : static bool
1937 heikki.linnakangas@i 7909 : 23496 : can_partial_agg(PlannerInfo *root)
7910 : : {
2970 rhaas@postgresql.org 7911 : 23496 : Query *parse = root->parse;
7912 : :
2917 7913 [ + + - + ]: 23496 : if (!parse->hasAggs && parse->groupClause == NIL)
7914 : : {
7915 : : /*
7916 : : * We don't know how to do parallel aggregation unless we have either
7917 : : * some aggregates or a grouping clause.
7918 : : */
2970 rhaas@postgresql.org 7919 :UBC 0 : return false;
7920 : : }
2970 rhaas@postgresql.org 7921 [ + + ]:CBC 23496 : else if (parse->groupingSets)
7922 : : {
7923 : : /* We don't know how to do grouping sets in parallel. */
7924 : 507 : return false;
7925 : : }
1937 heikki.linnakangas@i 7926 [ + + + + ]: 22989 : else if (root->hasNonPartialAggs || root->hasNonSerialAggs)
7927 : : {
7928 : : /* Insufficient support for partial mode. */
2970 rhaas@postgresql.org 7929 : 2308 : return false;
7930 : : }
7931 : :
7932 : : /* Everything looks good. */
7933 : 20681 : return true;
7934 : : }
7935 : :
7936 : : /*
7937 : : * apply_scanjoin_target_to_paths
7938 : : *
7939 : : * Adjust the final scan/join relation, and recursively all of its children,
7940 : : * to generate the final scan/join target. It would be more correct to model
7941 : : * this as a separate planning step with a new RelOptInfo at the toplevel and
7942 : : * for each child relation, but doing it this way is noticeably cheaper.
7943 : : * Maybe that problem can be solved at some point, but for now we do this.
7944 : : *
7945 : : * If tlist_same_exprs is true, then the scan/join target to be applied has
7946 : : * the same expressions as the existing reltarget, so we need only insert the
7947 : : * appropriate sortgroupref information. By avoiding the creation of
7948 : : * projection paths we save effort both immediately and at plan creation time.
7949 : : */
7950 : : static void
2915 7951 : 294646 : apply_scanjoin_target_to_paths(PlannerInfo *root,
7952 : : RelOptInfo *rel,
7953 : : List *scanjoin_targets,
7954 : : List *scanjoin_targets_contain_srfs,
7955 : : bool scanjoin_target_parallel_safe,
7956 : : bool tlist_same_exprs)
7957 : : {
2565 tgl@sss.pgh.pa.us 7958 [ + + + + : 294646 : bool rel_is_partitioned = IS_PARTITIONED_REL(rel);
+ + + - +
+ ]
7959 : : PathTarget *scanjoin_target;
7960 : : ListCell *lc;
7961 : :
7962 : : /* This recurses, so be paranoid. */
2908 rhaas@postgresql.org 7963 : 294646 : check_stack_depth();
7964 : :
7965 : : /*
7966 : : * If the rel only has Append and MergeAppend paths, we want to drop its
7967 : : * existing paths and generate new ones. This function would still be
7968 : : * correct if we kept the existing paths: we'd modify them to generate the
7969 : : * correct target above the partitioning Append, and then they'd compete
7970 : : * on cost with paths generating the target below the Append. However, in
7971 : : * our current cost model the latter way is always the same or cheaper
7972 : : * cost, so modifying the existing paths would just be useless work.
7973 : : * Moreover, when the cost is the same, varying roundoff errors might
7974 : : * sometimes allow an existing path to be picked, resulting in undesirable
7975 : : * cross-platform plan variations. So we drop old paths and thereby force
7976 : : * the work to be done below the Append.
7977 : : *
7978 : : * However, there are several cases when this optimization is not safe. If
7979 : : * the rel isn't partitioned, then none of the paths will be Append or
7980 : : * MergeAppend paths, so we should definitely not do this. If it is
7981 : : * partitioned but is a joinrel, it may have Append and MergeAppend paths,
7982 : : * but it can also have join paths that we can't afford to discard.
7983 : : *
7984 : : * Some care is needed, because we have to allow
7985 : : * generate_useful_gather_paths to see the old partial paths in the next
7986 : : * stanza. Hence, zap the main pathlist here, then allow
7987 : : * generate_useful_gather_paths to add path(s) to the main list, and
7988 : : * finally zap the partial pathlist.
7989 : : */
100 rhaas@postgresql.org 7990 [ + + + + :GNC 294646 : if (rel_is_partitioned && IS_SIMPLE_REL(rel))
+ + ]
2565 tgl@sss.pgh.pa.us 7991 :CBC 5876 : rel->pathlist = NIL;
7992 : :
7993 : : /*
7994 : : * If the scan/join target is not parallel-safe, partial paths cannot
7995 : : * generate it.
7996 : : */
2908 rhaas@postgresql.org 7997 [ + + ]: 294646 : if (!scanjoin_target_parallel_safe)
7998 : : {
7999 : : /*
8000 : : * Since we can't generate the final scan/join target in parallel
8001 : : * workers, this is our last opportunity to use any partial paths that
8002 : : * exist; so build Gather path(s) that use them and emit whatever the
8003 : : * current reltarget is. We don't do this in the case where the
8004 : : * target is parallel-safe, since we will be able to generate superior
8005 : : * paths by doing it after the final scan/join target has been
8006 : : * applied.
8007 : : */
2168 tomas.vondra@postgre 8008 : 42512 : generate_useful_gather_paths(root, rel, false);
8009 : :
8010 : : /* Can't use parallel query above this level. */
2908 rhaas@postgresql.org 8011 : 42512 : rel->partial_pathlist = NIL;
8012 : 42512 : rel->consider_parallel = false;
8013 : : }
8014 : :
8015 : : /* Finish dropping old paths for a partitioned rel, per comment above */
100 rhaas@postgresql.org 8016 [ + + + + :GNC 294646 : if (rel_is_partitioned && IS_SIMPLE_REL(rel))
+ + ]
2908 rhaas@postgresql.org 8017 :CBC 5876 : rel->partial_pathlist = NIL;
8018 : :
8019 : : /* Extract SRF-free scan/join target. */
8020 : 294646 : scanjoin_target = linitial_node(PathTarget, scanjoin_targets);
8021 : :
8022 : : /*
8023 : : * Apply the SRF-free scan/join target to each existing path.
8024 : : *
8025 : : * If the tlist exprs are the same, we can just inject the sortgroupref
8026 : : * information into the existing pathtargets. Otherwise, replace each
8027 : : * path with a projection path that generates the SRF-free scan/join
8028 : : * target. This can't change the ordering of paths within rel->pathlist,
8029 : : * so we just modify the list in place.
8030 : : */
2915 8031 [ + + + + : 613788 : foreach(lc, rel->pathlist)
+ + ]
8032 : : {
8033 : 319142 : Path *subpath = (Path *) lfirst(lc);
8034 : :
8035 : : /* Shouldn't have any parameterized paths anymore */
8036 [ - + ]: 319142 : Assert(subpath->param_info == NULL);
8037 : :
2908 8038 [ + + ]: 319142 : if (tlist_same_exprs)
8039 : 118266 : subpath->pathtarget->sortgrouprefs =
8040 : 118266 : scanjoin_target->sortgrouprefs;
8041 : : else
8042 : : {
8043 : : Path *newpath;
8044 : :
2915 8045 : 200876 : newpath = (Path *) create_projection_path(root, rel, subpath,
8046 : : scanjoin_target);
8047 : 200876 : lfirst(lc) = newpath;
8048 : : }
8049 : : }
8050 : :
8051 : : /* Likewise adjust the targets for any partial paths. */
2908 8052 [ + + + + : 307387 : foreach(lc, rel->partial_pathlist)
+ + ]
8053 : : {
8054 : 12741 : Path *subpath = (Path *) lfirst(lc);
8055 : :
8056 : : /* Shouldn't have any parameterized paths anymore */
8057 [ - + ]: 12741 : Assert(subpath->param_info == NULL);
8058 : :
8059 [ + + ]: 12741 : if (tlist_same_exprs)
8060 : 10227 : subpath->pathtarget->sortgrouprefs =
8061 : 10227 : scanjoin_target->sortgrouprefs;
8062 : : else
8063 : : {
8064 : : Path *newpath;
8065 : :
2565 tgl@sss.pgh.pa.us 8066 : 2514 : newpath = (Path *) create_projection_path(root, rel, subpath,
8067 : : scanjoin_target);
2915 rhaas@postgresql.org 8068 : 2514 : lfirst(lc) = newpath;
8069 : : }
8070 : : }
8071 : :
8072 : : /*
8073 : : * Now, if final scan/join target contains SRFs, insert ProjectSetPath(s)
8074 : : * atop each existing path. (Note that this function doesn't look at the
8075 : : * cheapest-path fields, which is a good thing because they're bogus right
8076 : : * now.)
8077 : : */
2908 8078 [ + + ]: 294646 : if (root->parse->hasTargetSRFs)
8079 : 6519 : adjust_paths_for_srfs(root, rel,
8080 : : scanjoin_targets,
8081 : : scanjoin_targets_contain_srfs);
8082 : :
8083 : : /*
8084 : : * Update the rel's target to be the final (with SRFs) scan/join target.
8085 : : * This now matches the actual output of all the paths, and we might get
8086 : : * confused in createplan.c if they don't agree. We must do this now so
8087 : : * that any append paths made in the next part will use the correct
8088 : : * pathtarget (cf. create_append_path).
8089 : : *
8090 : : * Note that this is also necessary if GetForeignUpperPaths() gets called
8091 : : * on the final scan/join relation or on any of its children, since the
8092 : : * FDW might look at the rel's target to create ForeignPaths.
8093 : : */
2565 tgl@sss.pgh.pa.us 8094 : 294646 : rel->reltarget = llast_node(PathTarget, scanjoin_targets);
8095 : :
8096 : : /*
8097 : : * If the relation is partitioned, recursively apply the scan/join target
8098 : : * to all partitions, and generate brand-new Append paths in which the
8099 : : * scan/join target is computed below the Append rather than above it.
8100 : : * Since Append is not projection-capable, that might save a separate
8101 : : * Result node, and it also is important for partitionwise aggregate.
8102 : : */
8103 [ + + ]: 294646 : if (rel_is_partitioned)
8104 : : {
2908 rhaas@postgresql.org 8105 : 6665 : List *live_children = NIL;
8106 : : int i;
8107 : :
8108 : : /* Adjust each partition. */
1685 drowley@postgresql.o 8109 : 6665 : i = -1;
8110 [ + + ]: 19089 : while ((i = bms_next_member(rel->live_parts, i)) >= 0)
8111 : : {
8112 : 12424 : RelOptInfo *child_rel = rel->part_rels[i];
8113 : : AppendRelInfo **appinfos;
8114 : : int nappinfos;
2908 rhaas@postgresql.org 8115 : 12424 : List *child_scanjoin_targets = NIL;
8116 : :
1685 drowley@postgresql.o 8117 [ - + ]: 12424 : Assert(child_rel != NULL);
8118 : :
8119 : : /* Dummy children can be ignored. */
8120 [ + + ]: 12424 : if (IS_DUMMY_REL(child_rel))
2542 tgl@sss.pgh.pa.us 8121 : 24 : continue;
8122 : :
8123 : : /* Translate scan/join targets for this child. */
2908 rhaas@postgresql.org 8124 : 12400 : appinfos = find_appinfos_by_relids(root, child_rel->relids,
8125 : : &nappinfos);
8126 [ + - + + : 24800 : foreach(lc, scanjoin_targets)
+ + ]
8127 : : {
8128 : 12400 : PathTarget *target = lfirst_node(PathTarget, lc);
8129 : :
8130 : 12400 : target = copy_pathtarget(target);
8131 : 12400 : target->exprs = (List *)
8132 : 12400 : adjust_appendrel_attrs(root,
8133 : 12400 : (Node *) target->exprs,
8134 : : nappinfos, appinfos);
8135 : 12400 : child_scanjoin_targets = lappend(child_scanjoin_targets,
8136 : : target);
8137 : : }
8138 : 12400 : pfree(appinfos);
8139 : :
8140 : : /* Recursion does the real work. */
8141 : 12400 : apply_scanjoin_target_to_paths(root, child_rel,
8142 : : child_scanjoin_targets,
8143 : : scanjoin_targets_contain_srfs,
8144 : : scanjoin_target_parallel_safe,
8145 : : tlist_same_exprs);
8146 : :
8147 : : /* Save non-dummy children for Append paths. */
8148 [ + - ]: 12400 : if (!IS_DUMMY_REL(child_rel))
8149 : 12400 : live_children = lappend(live_children, child_rel);
8150 : : }
8151 : :
8152 : : /* Build new paths for this relation by appending child paths. */
2565 tgl@sss.pgh.pa.us 8153 : 6665 : add_paths_to_append_rel(root, rel, live_children);
8154 : : }
8155 : :
8156 : : /*
8157 : : * Consider generating Gather or Gather Merge paths. We must only do this
8158 : : * if the relation is parallel safe, and we don't do it for child rels to
8159 : : * avoid creating multiple Gather nodes within the same plan. We must do
8160 : : * this after all paths have been generated and before set_cheapest, since
8161 : : * one of the generated paths may turn out to be the cheapest one.
8162 : : */
2908 rhaas@postgresql.org 8163 [ + + + + : 294646 : if (rel->consider_parallel && !IS_OTHER_REL(rel))
+ + + - ]
2168 tomas.vondra@postgre 8164 : 99442 : generate_useful_gather_paths(root, rel, false);
8165 : :
8166 : : /*
8167 : : * Reassess which paths are the cheapest, now that we've potentially added
8168 : : * new Gather (or Gather Merge) and/or Append (or MergeAppend) paths to
8169 : : * this relation.
8170 : : */
2908 rhaas@postgresql.org 8171 : 294646 : set_cheapest(rel);
2915 8172 : 294646 : }
8173 : :
8174 : : /*
8175 : : * create_partitionwise_grouping_paths
8176 : : *
8177 : : * If the partition keys of input relation are part of the GROUP BY clause, all
8178 : : * the rows belonging to a given group come from a single partition. This
8179 : : * allows aggregation/grouping over a partitioned relation to be broken down
8180 : : * into aggregation/grouping on each partition. This should be no worse, and
8181 : : * often better, than the normal approach.
8182 : : *
8183 : : * However, if the GROUP BY clause does not contain all the partition keys,
8184 : : * rows from a given group may be spread across multiple partitions. In that
8185 : : * case, we perform partial aggregation for each group, append the results,
8186 : : * and then finalize aggregation. This is less certain to win than the
8187 : : * previous case. It may win if the PartialAggregate stage greatly reduces
8188 : : * the number of groups, because fewer rows will pass through the Append node.
8189 : : * It may lose if we have lots of small groups.
8190 : : */
8191 : : static void
8192 : 413 : create_partitionwise_grouping_paths(PlannerInfo *root,
8193 : : RelOptInfo *input_rel,
8194 : : RelOptInfo *grouped_rel,
8195 : : RelOptInfo *partially_grouped_rel,
8196 : : const AggClauseCosts *agg_costs,
8197 : : grouping_sets_data *gd,
8198 : : PartitionwiseAggregateType patype,
8199 : : GroupPathExtraData *extra)
8200 : : {
8201 : 413 : List *grouped_live_children = NIL;
8202 : 413 : List *partially_grouped_live_children = NIL;
2908 8203 : 413 : PathTarget *target = grouped_rel->reltarget;
2823 8204 : 413 : bool partial_grouping_valid = true;
8205 : : int i;
8206 : :
2915 8207 [ - + ]: 413 : Assert(patype != PARTITIONWISE_AGGREGATE_NONE);
8208 [ + + - + ]: 413 : Assert(patype != PARTITIONWISE_AGGREGATE_PARTIAL ||
8209 : : partially_grouped_rel != NULL);
8210 : :
8211 : : /* Add paths for partitionwise aggregation/grouping. */
1685 drowley@postgresql.o 8212 : 413 : i = -1;
8213 [ + + ]: 1496 : while ((i = bms_next_member(input_rel->live_parts, i)) >= 0)
8214 : : {
8215 : 1083 : RelOptInfo *child_input_rel = input_rel->part_rels[i];
8216 : : PathTarget *child_target;
8217 : : AppendRelInfo **appinfos;
8218 : : int nappinfos;
8219 : : GroupPathExtraData child_extra;
8220 : : RelOptInfo *child_grouped_rel;
8221 : : RelOptInfo *child_partially_grouped_rel;
8222 : :
8223 [ - + ]: 1083 : Assert(child_input_rel != NULL);
8224 : :
8225 : : /* Dummy children can be ignored. */
8226 [ - + ]: 1083 : if (IS_DUMMY_REL(child_input_rel))
2542 tgl@sss.pgh.pa.us 8227 :UBC 0 : continue;
8228 : :
1685 drowley@postgresql.o 8229 :CBC 1083 : child_target = copy_pathtarget(target);
8230 : :
8231 : : /*
8232 : : * Copy the given "extra" structure as is and then override the
8233 : : * members specific to this child.
8234 : : */
2915 rhaas@postgresql.org 8235 : 1083 : memcpy(&child_extra, extra, sizeof(child_extra));
8236 : :
8237 : 1083 : appinfos = find_appinfos_by_relids(root, child_input_rel->relids,
8238 : : &nappinfos);
8239 : :
8240 : 1083 : child_target->exprs = (List *)
8241 : 1083 : adjust_appendrel_attrs(root,
8242 : 1083 : (Node *) target->exprs,
8243 : : nappinfos, appinfos);
8244 : :
8245 : : /* Translate havingQual and targetList. */
8246 : 1083 : child_extra.havingQual = (Node *)
8247 : : adjust_appendrel_attrs(root,
8248 : : extra->havingQual,
8249 : : nappinfos, appinfos);
8250 : 1083 : child_extra.targetList = (List *)
8251 : 1083 : adjust_appendrel_attrs(root,
8252 : 1083 : (Node *) extra->targetList,
8253 : : nappinfos, appinfos);
8254 : :
8255 : : /*
8256 : : * extra->patype was the value computed for our parent rel; patype is
8257 : : * the value for this relation. For the child, our value is its
8258 : : * parent rel's value.
8259 : : */
8260 : 1083 : child_extra.patype = patype;
8261 : :
8262 : : /*
8263 : : * Create grouping relation to hold fully aggregated grouping and/or
8264 : : * aggregation paths for the child.
8265 : : */
8266 : 1083 : child_grouped_rel = make_grouping_rel(root, child_input_rel,
8267 : : child_target,
8268 : 1083 : extra->target_parallel_safe,
8269 : : child_extra.havingQual);
8270 : :
8271 : : /* Create grouping paths for this child relation. */
8272 : 1083 : create_ordinary_grouping_paths(root, child_input_rel,
8273 : : child_grouped_rel,
8274 : : agg_costs, gd, &child_extra,
8275 : : &child_partially_grouped_rel);
8276 : :
8277 [ + + ]: 1083 : if (child_partially_grouped_rel)
8278 : : {
8279 : : partially_grouped_live_children =
8280 : 771 : lappend(partially_grouped_live_children,
8281 : : child_partially_grouped_rel);
8282 : : }
8283 : : else
2823 8284 : 312 : partial_grouping_valid = false;
8285 : :
2915 8286 [ + + ]: 1083 : if (patype == PARTITIONWISE_AGGREGATE_FULL)
8287 : : {
8288 : 654 : set_cheapest(child_grouped_rel);
8289 : 654 : grouped_live_children = lappend(grouped_live_children,
8290 : : child_grouped_rel);
8291 : : }
8292 : :
8293 : 1083 : pfree(appinfos);
8294 : : }
8295 : :
8296 : : /*
8297 : : * Try to create append paths for partially grouped children. For full
8298 : : * partitionwise aggregation, we might have paths in the partial_pathlist
8299 : : * if parallel aggregation is possible. For partial partitionwise
8300 : : * aggregation, we may have paths in both pathlist and partial_pathlist.
8301 : : *
8302 : : * NB: We must have a partially grouped path for every child in order to
8303 : : * generate a partially grouped path for this relation.
8304 : : */
2823 8305 [ + + + + ]: 413 : if (partially_grouped_rel && partial_grouping_valid)
8306 : : {
8307 [ - + ]: 301 : Assert(partially_grouped_live_children != NIL);
8308 : :
2915 8309 : 301 : add_paths_to_append_rel(root, partially_grouped_rel,
8310 : : partially_grouped_live_children);
8311 : : }
8312 : :
8313 : : /* If possible, create append paths for fully grouped children. */
8314 [ + + ]: 413 : if (patype == PARTITIONWISE_AGGREGATE_FULL)
8315 : : {
2823 8316 [ - + ]: 244 : Assert(grouped_live_children != NIL);
8317 : :
2915 8318 : 244 : add_paths_to_append_rel(root, grouped_rel, grouped_live_children);
8319 : : }
8320 : 413 : }
8321 : :
8322 : : /*
8323 : : * group_by_has_partkey
8324 : : *
8325 : : * Returns true if all the partition keys of the given relation are part of
8326 : : * the GROUP BY clauses, including having matching collation, false otherwise.
8327 : : */
8328 : : static bool
8329 : 386 : group_by_has_partkey(RelOptInfo *input_rel,
8330 : : List *targetList,
8331 : : List *groupClause)
8332 : : {
8333 : 386 : List *groupexprs = get_sortgrouplist_exprs(groupClause, targetList);
8334 : 386 : int cnt = 0;
8335 : : int partnatts;
8336 : :
8337 : : /* Input relation should be partitioned. */
8338 [ - + ]: 386 : Assert(input_rel->part_scheme);
8339 : :
8340 : : /* Rule out early, if there are no partition keys present. */
8341 [ - + ]: 386 : if (!input_rel->partexprs)
2915 rhaas@postgresql.org 8342 :UBC 0 : return false;
8343 : :
2915 rhaas@postgresql.org 8344 :CBC 386 : partnatts = input_rel->part_scheme->partnatts;
8345 : :
8346 [ + + ]: 648 : for (cnt = 0; cnt < partnatts; cnt++)
8347 : : {
8348 : 404 : List *partexprs = input_rel->partexprs[cnt];
8349 : : ListCell *lc;
8350 : 404 : bool found = false;
8351 : :
8352 [ + + + + : 603 : foreach(lc, partexprs)
+ + ]
8353 : : {
8354 : : ListCell *lg;
8355 : 467 : Expr *partexpr = lfirst(lc);
492 amitlan@postgresql.o 8356 : 467 : Oid partcoll = input_rel->part_scheme->partcollation[cnt];
8357 : :
8358 [ + - + + : 726 : foreach(lg, groupexprs)
+ + ]
8359 : : {
8360 : 527 : Expr *groupexpr = lfirst(lg);
8361 : 527 : Oid groupcoll = exprCollation((Node *) groupexpr);
8362 : :
8363 : : /*
8364 : : * Note: we can assume there is at most one RelabelType node;
8365 : : * eval_const_expressions() will have simplified if more than
8366 : : * one.
8367 : : */
8368 [ + + ]: 527 : if (IsA(groupexpr, RelabelType))
8369 : 12 : groupexpr = ((RelabelType *) groupexpr)->arg;
8370 : :
8371 [ + + ]: 527 : if (equal(groupexpr, partexpr))
8372 : : {
8373 : : /*
8374 : : * Reject a match if the grouping collation does not match
8375 : : * the partitioning collation.
8376 : : */
8377 [ + + + - : 268 : if (OidIsValid(partcoll) && OidIsValid(groupcoll) &&
+ + ]
8378 : : partcoll != groupcoll)
8379 : 6 : return false;
8380 : :
8381 : 262 : found = true;
8382 : 262 : break;
8383 : : }
8384 : : }
8385 : :
8386 [ + + ]: 461 : if (found)
8387 : 262 : break;
8388 : : }
8389 : :
8390 : : /*
8391 : : * If none of the partition key expressions match with any of the
8392 : : * GROUP BY expression, return false.
8393 : : */
2915 rhaas@postgresql.org 8394 [ + + ]: 398 : if (!found)
8395 : 136 : return false;
8396 : : }
8397 : :
8398 : 244 : return true;
8399 : : }
8400 : :
8401 : : /*
8402 : : * generate_setop_child_grouplist
8403 : : * Build a SortGroupClause list defining the sort/grouping properties
8404 : : * of the child of a set operation.
8405 : : *
8406 : : * This is similar to generate_setop_grouplist() but differs as the setop
8407 : : * child query's targetlist entries may already have a tleSortGroupRef
8408 : : * assigned for other purposes, such as GROUP BYs. Here we keep the
8409 : : * SortGroupClause list in the same order as 'op' groupClauses and just adjust
8410 : : * the tleSortGroupRef to reference the TargetEntry's 'ressortgroupref'. If
8411 : : * any of the columns in the targetlist don't match to the setop's colTypes
8412 : : * then we return an empty list. This may leave some TLEs with unreferenced
8413 : : * ressortgroupref markings, but that's harmless.
8414 : : */
8415 : : static List *
663 8416 : 6460 : generate_setop_child_grouplist(SetOperationStmt *op, List *targetlist)
8417 : : {
8418 : 6460 : List *grouplist = copyObject(op->groupClauses);
8419 : : ListCell *lg;
8420 : : ListCell *lt;
8421 : : ListCell *ct;
8422 : :
8423 : 6460 : lg = list_head(grouplist);
429 drowley@postgresql.o 8424 : 6460 : ct = list_head(op->colTypes);
663 rhaas@postgresql.org 8425 [ + + + + : 25191 : foreach(lt, targetlist)
+ + ]
8426 : : {
8427 : 18938 : TargetEntry *tle = (TargetEntry *) lfirst(lt);
8428 : : SortGroupClause *sgc;
8429 : : Oid coltype;
8430 : :
8431 : : /* resjunk columns could have sortgrouprefs. Leave these alone */
8432 [ - + ]: 18938 : if (tle->resjunk)
663 rhaas@postgresql.org 8433 :UBC 0 : continue;
8434 : :
8435 : : /*
8436 : : * We expect every non-resjunk target to have a SortGroupClause and
8437 : : * colTypes.
8438 : : */
663 rhaas@postgresql.org 8439 [ - + ]:CBC 18938 : Assert(lg != NULL);
429 drowley@postgresql.o 8440 [ - + ]: 18938 : Assert(ct != NULL);
663 rhaas@postgresql.org 8441 : 18938 : sgc = (SortGroupClause *) lfirst(lg);
429 drowley@postgresql.o 8442 : 18938 : coltype = lfirst_oid(ct);
8443 : :
8444 : : /* reject if target type isn't the same as the setop target type */
8445 [ + + ]: 18938 : if (coltype != exprType((Node *) tle->expr))
8446 : 207 : return NIL;
8447 : :
663 rhaas@postgresql.org 8448 : 18731 : lg = lnext(grouplist, lg);
429 drowley@postgresql.o 8449 : 18731 : ct = lnext(op->colTypes, ct);
8450 : :
8451 : : /* assign a tleSortGroupRef, or reuse the existing one */
663 rhaas@postgresql.org 8452 : 18731 : sgc->tleSortGroupRef = assignSortGroupRef(tle, targetlist);
8453 : : }
8454 : :
8455 [ - + ]: 6253 : Assert(lg == NULL);
429 drowley@postgresql.o 8456 [ - + ]: 6253 : Assert(ct == NULL);
8457 : :
663 rhaas@postgresql.org 8458 : 6253 : return grouplist;
8459 : : }
8460 : :
8461 : : /*
8462 : : * create_unique_paths
8463 : : * Build a new RelOptInfo containing Paths that represent elimination of
8464 : : * distinct rows from the input data. Distinct-ness is defined according to
8465 : : * the needs of the semijoin represented by sjinfo. If it is not possible
8466 : : * to identify how to make the data unique, NULL is returned.
8467 : : *
8468 : : * If used at all, this is likely to be called repeatedly on the same rel,
8469 : : * so we cache the result.
8470 : : */
8471 : : RelOptInfo *
208 rguo@postgresql.org 8472 :GNC 4489 : create_unique_paths(PlannerInfo *root, RelOptInfo *rel, SpecialJoinInfo *sjinfo)
8473 : : {
8474 : : RelOptInfo *unique_rel;
8475 : 4489 : List *sortPathkeys = NIL;
8476 : 4489 : List *groupClause = NIL;
8477 : : MemoryContext oldcontext;
8478 : :
8479 : : /* Caller made a mistake if SpecialJoinInfo is the wrong one */
8480 [ - + ]: 4489 : Assert(sjinfo->jointype == JOIN_SEMI);
8481 [ - + ]: 4489 : Assert(bms_equal(rel->relids, sjinfo->syn_righthand));
8482 : :
8483 : : /* If result already cached, return it */
8484 [ + + ]: 4489 : if (rel->unique_rel)
8485 : 918 : return rel->unique_rel;
8486 : :
8487 : : /* If it's not possible to unique-ify, return NULL */
8488 [ + + + - ]: 3571 : if (!(sjinfo->semi_can_btree || sjinfo->semi_can_hash))
8489 : 66 : return NULL;
8490 : :
8491 : : /*
8492 : : * Punt if this is a child relation and we failed to build a unique-ified
8493 : : * relation for its parent. This can happen if all the RHS columns were
8494 : : * found to be equated to constants when unique-ifying the parent table,
8495 : : * leaving no columns to unique-ify.
8496 : : */
198 8497 [ + + + + : 3505 : if (IS_OTHER_REL(rel) && rel->top_parent->unique_rel == NULL)
- + + + ]
8498 : 6 : return NULL;
8499 : :
8500 : : /*
8501 : : * When called during GEQO join planning, we are in a short-lived memory
8502 : : * context. We must make sure that the unique rel and any subsidiary data
8503 : : * structures created for a baserel survive the GEQO cycle, else the
8504 : : * baserel is trashed for future GEQO cycles. On the other hand, when we
8505 : : * are creating those for a joinrel during GEQO, we don't want them to
8506 : : * clutter the main planning context. Upshot is that the best solution is
8507 : : * to explicitly allocate memory in the same context the given RelOptInfo
8508 : : * is in.
8509 : : */
208 8510 : 3499 : oldcontext = MemoryContextSwitchTo(GetMemoryChunkContext(rel));
8511 : :
8512 : 3499 : unique_rel = makeNode(RelOptInfo);
8513 : 3499 : memcpy(unique_rel, rel, sizeof(RelOptInfo));
8514 : :
8515 : : /*
8516 : : * clear path info
8517 : : */
8518 : 3499 : unique_rel->pathlist = NIL;
8519 : 3499 : unique_rel->ppilist = NIL;
8520 : 3499 : unique_rel->partial_pathlist = NIL;
8521 : 3499 : unique_rel->cheapest_startup_path = NULL;
8522 : 3499 : unique_rel->cheapest_total_path = NULL;
8523 : 3499 : unique_rel->cheapest_parameterized_paths = NIL;
8524 : :
8525 : : /*
8526 : : * Build the target list for the unique rel. We also build the pathkeys
8527 : : * that represent the ordering requirements for the sort-based
8528 : : * implementation, and the list of SortGroupClause nodes that represent
8529 : : * the columns to be grouped on for the hash-based implementation.
8530 : : *
8531 : : * For a child rel, we can construct these fields from those of its
8532 : : * parent.
8533 : : */
8534 [ + + + + : 3499 : if (IS_OTHER_REL(rel))
- + ]
8535 : 216 : {
8536 : : PathTarget *child_unique_target;
8537 : : PathTarget *parent_unique_target;
8538 : :
8539 : 216 : parent_unique_target = rel->top_parent->unique_rel->reltarget;
8540 : :
8541 : 216 : child_unique_target = copy_pathtarget(parent_unique_target);
8542 : :
8543 : : /* Translate the target expressions */
8544 : 216 : child_unique_target->exprs = (List *)
8545 : 216 : adjust_appendrel_attrs_multilevel(root,
8546 : 216 : (Node *) parent_unique_target->exprs,
8547 : : rel,
8548 : 216 : rel->top_parent);
8549 : :
8550 : 216 : unique_rel->reltarget = child_unique_target;
8551 : :
8552 : 216 : sortPathkeys = rel->top_parent->unique_pathkeys;
8553 : 216 : groupClause = rel->top_parent->unique_groupclause;
8554 : : }
8555 : : else
8556 : : {
8557 : : List *newtlist;
8558 : : int nextresno;
8559 : 3283 : List *sortList = NIL;
8560 : : ListCell *lc1;
8561 : : ListCell *lc2;
8562 : :
8563 : : /*
8564 : : * The values we are supposed to unique-ify may be expressions in the
8565 : : * variables of the input rel's targetlist. We have to add any such
8566 : : * expressions to the unique rel's targetlist.
8567 : : *
8568 : : * To complicate matters, some of the values to be unique-ified may be
8569 : : * known redundant by the EquivalenceClass machinery (e.g., because
8570 : : * they have been equated to constants). There is no need to compare
8571 : : * such values during unique-ification, and indeed we had better not
8572 : : * try because the Vars involved may not have propagated as high as
8573 : : * the semijoin's level. We use make_pathkeys_for_sortclauses to
8574 : : * detect such cases, which is a tad inefficient but it doesn't seem
8575 : : * worth building specialized infrastructure for this.
8576 : : */
8577 : 3283 : newtlist = make_tlist_from_pathtarget(rel->reltarget);
8578 : 3283 : nextresno = list_length(newtlist) + 1;
8579 : :
8580 [ + - + + : 6689 : forboth(lc1, sjinfo->semi_rhs_exprs, lc2, sjinfo->semi_operators)
+ - + + +
+ + - +
+ ]
8581 : : {
8582 : 3406 : Expr *uniqexpr = lfirst(lc1);
8583 : 3406 : Oid in_oper = lfirst_oid(lc2);
8584 : : Oid sortop;
8585 : : TargetEntry *tle;
199 tgl@sss.pgh.pa.us 8586 : 3406 : bool made_tle = false;
8587 : :
208 rguo@postgresql.org 8588 : 3406 : tle = tlist_member(uniqexpr, newtlist);
8589 [ + + ]: 3406 : if (!tle)
8590 : : {
103 peter@eisentraut.org 8591 : 1646 : tle = makeTargetEntry(uniqexpr,
8592 : : nextresno,
8593 : : NULL,
8594 : : false);
208 rguo@postgresql.org 8595 : 1646 : newtlist = lappend(newtlist, tle);
8596 : 1646 : nextresno++;
199 tgl@sss.pgh.pa.us 8597 : 1646 : made_tle = true;
8598 : : }
8599 : :
8600 : : /*
8601 : : * Try to build an ORDER BY list to sort the input compatibly. We
8602 : : * do this for each sortable clause even when the clauses are not
8603 : : * all sortable, so that we can detect clauses that are redundant
8604 : : * according to the pathkey machinery.
8605 : : */
8606 : 3406 : sortop = get_ordering_op_for_equality_op(in_oper, false);
8607 [ + - ]: 3406 : if (OidIsValid(sortop))
8608 : : {
8609 : : Oid eqop;
8610 : : SortGroupClause *sortcl;
8611 : :
8612 : : /*
8613 : : * The Unique node will need equality operators. Normally
8614 : : * these are the same as the IN clause operators, but if those
8615 : : * are cross-type operators then the equality operators are
8616 : : * the ones for the IN clause operators' RHS datatype.
8617 : : */
208 rguo@postgresql.org 8618 : 3406 : eqop = get_equality_op_for_ordering_op(sortop, NULL);
8619 [ - + ]: 3406 : if (!OidIsValid(eqop)) /* shouldn't happen */
208 rguo@postgresql.org 8620 [ # # ]:UNC 0 : elog(ERROR, "could not find equality operator for ordering operator %u",
8621 : : sortop);
8622 : :
208 rguo@postgresql.org 8623 :GNC 3406 : sortcl = makeNode(SortGroupClause);
8624 : 3406 : sortcl->tleSortGroupRef = assignSortGroupRef(tle, newtlist);
8625 : 3406 : sortcl->eqop = eqop;
8626 : 3406 : sortcl->sortop = sortop;
8627 : 3406 : sortcl->reverse_sort = false;
8628 : 3406 : sortcl->nulls_first = false;
8629 : 3406 : sortcl->hashable = false; /* no need to make this accurate */
8630 : 3406 : sortList = lappend(sortList, sortcl);
8631 : :
8632 : : /*
8633 : : * At each step, convert the SortGroupClause list to pathkey
8634 : : * form. If the just-added SortGroupClause is redundant, the
8635 : : * result will be shorter than the SortGroupClause list.
8636 : : */
199 tgl@sss.pgh.pa.us 8637 : 3406 : sortPathkeys = make_pathkeys_for_sortclauses(root, sortList,
8638 : : newtlist);
8639 [ + + ]: 3406 : if (list_length(sortPathkeys) != list_length(sortList))
8640 : : {
8641 : : /* Drop the redundant SortGroupClause */
8642 : 1026 : sortList = list_delete_last(sortList);
8643 [ - + ]: 1026 : Assert(list_length(sortPathkeys) == list_length(sortList));
8644 : : /* Undo tlist addition, if we made one */
8645 [ + + ]: 1026 : if (made_tle)
8646 : : {
8647 : 6 : newtlist = list_delete_last(newtlist);
8648 : 6 : nextresno--;
8649 : : }
8650 : : /* We need not consider this clause for hashing, either */
8651 : 1026 : continue;
8652 : : }
8653 : : }
199 tgl@sss.pgh.pa.us 8654 [ # # ]:UNC 0 : else if (sjinfo->semi_can_btree) /* shouldn't happen */
8655 [ # # ]: 0 : elog(ERROR, "could not find ordering operator for equality operator %u",
8656 : : in_oper);
8657 : :
208 rguo@postgresql.org 8658 [ + - ]:GNC 2380 : if (sjinfo->semi_can_hash)
8659 : : {
8660 : : /* Create a GROUP BY list for the Agg node to use */
8661 : : Oid eq_oper;
8662 : : SortGroupClause *groupcl;
8663 : :
8664 : : /*
8665 : : * Get the hashable equality operators for the Agg node to
8666 : : * use. Normally these are the same as the IN clause
8667 : : * operators, but if those are cross-type operators then the
8668 : : * equality operators are the ones for the IN clause
8669 : : * operators' RHS datatype.
8670 : : */
8671 [ - + ]: 2380 : if (!get_compatible_hash_operators(in_oper, NULL, &eq_oper))
208 rguo@postgresql.org 8672 [ # # ]:UNC 0 : elog(ERROR, "could not find compatible hash operator for operator %u",
8673 : : in_oper);
8674 : :
208 rguo@postgresql.org 8675 :GNC 2380 : groupcl = makeNode(SortGroupClause);
8676 : 2380 : groupcl->tleSortGroupRef = assignSortGroupRef(tle, newtlist);
8677 : 2380 : groupcl->eqop = eq_oper;
8678 : 2380 : groupcl->sortop = sortop;
8679 : 2380 : groupcl->reverse_sort = false;
8680 : 2380 : groupcl->nulls_first = false;
8681 : 2380 : groupcl->hashable = true;
8682 : 2380 : groupClause = lappend(groupClause, groupcl);
8683 : : }
8684 : : }
8685 : :
8686 : : /*
8687 : : * Done building the sortPathkeys and groupClause. But the
8688 : : * sortPathkeys are bogus if not all the clauses were sortable.
8689 : : */
199 tgl@sss.pgh.pa.us 8690 [ - + ]: 3283 : if (!sjinfo->semi_can_btree)
199 tgl@sss.pgh.pa.us 8691 :UNC 0 : sortPathkeys = NIL;
8692 : :
8693 : : /*
8694 : : * It can happen that all the RHS columns are equated to constants.
8695 : : * We'd have to do something special to unique-ify in that case, and
8696 : : * it's such an unlikely-in-the-real-world case that it's not worth
8697 : : * the effort. So just punt if we found no columns to unique-ify.
8698 : : */
199 tgl@sss.pgh.pa.us 8699 [ + + + - ]:GNC 3283 : if (sortPathkeys == NIL && groupClause == NIL)
8700 : : {
8701 : 975 : MemoryContextSwitchTo(oldcontext);
8702 : 975 : return NULL;
8703 : : }
8704 : :
8705 : : /* Convert the required targetlist back to PathTarget form */
208 rguo@postgresql.org 8706 : 2308 : unique_rel->reltarget = create_pathtarget(root, newtlist);
8707 : : }
8708 : :
8709 : : /* build unique paths based on input rel's pathlist */
8710 : 2524 : create_final_unique_paths(root, rel, sortPathkeys, groupClause,
8711 : : sjinfo, unique_rel);
8712 : :
8713 : : /* build unique paths based on input rel's partial_pathlist */
8714 : 2524 : create_partial_unique_paths(root, rel, sortPathkeys, groupClause,
8715 : : sjinfo, unique_rel);
8716 : :
8717 : : /* Now choose the best path(s) */
8718 : 2524 : set_cheapest(unique_rel);
8719 : :
8720 : : /*
8721 : : * There shouldn't be any partial paths for the unique relation;
8722 : : * otherwise, we won't be able to properly guarantee uniqueness.
8723 : : */
8724 [ - + ]: 2524 : Assert(unique_rel->partial_pathlist == NIL);
8725 : :
8726 : : /* Cache the result */
8727 : 2524 : rel->unique_rel = unique_rel;
8728 : 2524 : rel->unique_pathkeys = sortPathkeys;
8729 : 2524 : rel->unique_groupclause = groupClause;
8730 : :
8731 : 2524 : MemoryContextSwitchTo(oldcontext);
8732 : :
8733 : 2524 : return unique_rel;
8734 : : }
8735 : :
8736 : : /*
8737 : : * create_final_unique_paths
8738 : : * Create unique paths in 'unique_rel' based on 'input_rel' pathlist
8739 : : */
8740 : : static void
8741 : 4410 : create_final_unique_paths(PlannerInfo *root, RelOptInfo *input_rel,
8742 : : List *sortPathkeys, List *groupClause,
8743 : : SpecialJoinInfo *sjinfo, RelOptInfo *unique_rel)
8744 : : {
8745 : 4410 : Path *cheapest_input_path = input_rel->cheapest_total_path;
8746 : :
8747 : : /* Estimate number of output rows */
8748 : 4410 : unique_rel->rows = estimate_num_groups(root,
8749 : : sjinfo->semi_rhs_exprs,
8750 : : cheapest_input_path->rows,
8751 : : NULL,
8752 : : NULL);
8753 : :
8754 : : /* Consider sort-based implementations, if possible. */
8755 [ + - ]: 4410 : if (sjinfo->semi_can_btree)
8756 : : {
8757 : : ListCell *lc;
8758 : :
8759 : : /*
8760 : : * Use any available suitably-sorted path as input, and also consider
8761 : : * sorting the cheapest-total path and incremental sort on any paths
8762 : : * with presorted keys.
8763 : : *
8764 : : * To save planning time, we ignore parameterized input paths unless
8765 : : * they are the cheapest-total path.
8766 : : */
8767 [ + - + + : 9620 : foreach(lc, input_rel->pathlist)
+ + ]
8768 : : {
8769 : 5210 : Path *input_path = (Path *) lfirst(lc);
8770 : : Path *path;
8771 : : bool is_sorted;
8772 : : int presorted_keys;
8773 : :
8774 : : /*
8775 : : * Ignore parameterized paths that are not the cheapest-total
8776 : : * path.
8777 : : */
8778 [ + + + + ]: 5210 : if (input_path->param_info &&
8779 : : input_path != cheapest_input_path)
8780 : 469 : continue;
8781 : :
8782 : 4766 : is_sorted = pathkeys_count_contained_in(sortPathkeys,
8783 : : input_path->pathkeys,
8784 : : &presorted_keys);
8785 : :
8786 : : /*
8787 : : * Ignore paths that are not suitably or partially sorted, unless
8788 : : * they are the cheapest total path (no need to deal with paths
8789 : : * which have presorted keys when incremental sort is disabled).
8790 : : */
8791 [ + + + + ]: 4766 : if (!is_sorted && input_path != cheapest_input_path &&
8792 [ + + - + ]: 49 : (presorted_keys == 0 || !enable_incremental_sort))
8793 : 25 : continue;
8794 : :
8795 : : /*
8796 : : * Make a separate ProjectionPath in case we need a Result node.
8797 : : */
8798 : 4741 : path = (Path *) create_projection_path(root,
8799 : : unique_rel,
8800 : : input_path,
8801 : 4741 : unique_rel->reltarget);
8802 : :
8803 [ + + ]: 4741 : if (!is_sorted)
8804 : : {
8805 : : /*
8806 : : * We've no need to consider both a sort and incremental sort.
8807 : : * We'll just do a sort if there are no presorted keys and an
8808 : : * incremental sort when there are presorted keys.
8809 : : */
8810 [ + + - + ]: 2517 : if (presorted_keys == 0 || !enable_incremental_sort)
8811 : 2493 : path = (Path *) create_sort_path(root,
8812 : : unique_rel,
8813 : : path,
8814 : : sortPathkeys,
8815 : : -1.0);
8816 : : else
8817 : 24 : path = (Path *) create_incremental_sort_path(root,
8818 : : unique_rel,
8819 : : path,
8820 : : sortPathkeys,
8821 : : presorted_keys,
8822 : : -1.0);
8823 : : }
8824 : :
8825 : 4741 : path = (Path *) create_unique_path(root, unique_rel, path,
8826 : : list_length(sortPathkeys),
8827 : : unique_rel->rows);
8828 : :
8829 : 4741 : add_path(unique_rel, path);
8830 : : }
8831 : : }
8832 : :
8833 : : /* Consider hash-based implementation, if possible. */
8834 [ + - ]: 4410 : if (sjinfo->semi_can_hash)
8835 : : {
8836 : : Path *path;
8837 : :
8838 : : /*
8839 : : * Make a separate ProjectionPath in case we need a Result node.
8840 : : */
8841 : 4410 : path = (Path *) create_projection_path(root,
8842 : : unique_rel,
8843 : : cheapest_input_path,
8844 : 4410 : unique_rel->reltarget);
8845 : :
8846 : 4410 : path = (Path *) create_agg_path(root,
8847 : : unique_rel,
8848 : : path,
8849 : : cheapest_input_path->pathtarget,
8850 : : AGG_HASHED,
8851 : : AGGSPLIT_SIMPLE,
8852 : : groupClause,
8853 : : NIL,
8854 : : NULL,
8855 : : unique_rel->rows);
8856 : :
8857 : 4410 : add_path(unique_rel, path);
8858 : : }
8859 : 4410 : }
8860 : :
8861 : : /*
8862 : : * create_partial_unique_paths
8863 : : * Create unique paths in 'unique_rel' based on 'input_rel' partial_pathlist
8864 : : */
8865 : : static void
8866 : 2524 : create_partial_unique_paths(PlannerInfo *root, RelOptInfo *input_rel,
8867 : : List *sortPathkeys, List *groupClause,
8868 : : SpecialJoinInfo *sjinfo, RelOptInfo *unique_rel)
8869 : : {
8870 : : RelOptInfo *partial_unique_rel;
8871 : : Path *cheapest_partial_path;
8872 : :
8873 : : /* nothing to do when there are no partial paths in the input rel */
8874 [ + + + + ]: 2524 : if (!input_rel->consider_parallel || input_rel->partial_pathlist == NIL)
8875 : 638 : return;
8876 : :
8877 : : /*
8878 : : * nothing to do if there's anything in the targetlist that's
8879 : : * parallel-restricted.
8880 : : */
8881 [ - + ]: 1886 : if (!is_parallel_safe(root, (Node *) unique_rel->reltarget->exprs))
208 rguo@postgresql.org 8882 :UNC 0 : return;
8883 : :
208 rguo@postgresql.org 8884 :GNC 1886 : cheapest_partial_path = linitial(input_rel->partial_pathlist);
8885 : :
8886 : 1886 : partial_unique_rel = makeNode(RelOptInfo);
8887 : 1886 : memcpy(partial_unique_rel, input_rel, sizeof(RelOptInfo));
8888 : :
8889 : : /*
8890 : : * clear path info
8891 : : */
8892 : 1886 : partial_unique_rel->pathlist = NIL;
8893 : 1886 : partial_unique_rel->ppilist = NIL;
8894 : 1886 : partial_unique_rel->partial_pathlist = NIL;
8895 : 1886 : partial_unique_rel->cheapest_startup_path = NULL;
8896 : 1886 : partial_unique_rel->cheapest_total_path = NULL;
8897 : 1886 : partial_unique_rel->cheapest_parameterized_paths = NIL;
8898 : :
8899 : : /* Estimate number of output rows */
8900 : 1886 : partial_unique_rel->rows = estimate_num_groups(root,
8901 : : sjinfo->semi_rhs_exprs,
8902 : : cheapest_partial_path->rows,
8903 : : NULL,
8904 : : NULL);
8905 : 1886 : partial_unique_rel->reltarget = unique_rel->reltarget;
8906 : :
8907 : : /* Consider sort-based implementations, if possible. */
8908 [ + - ]: 1886 : if (sjinfo->semi_can_btree)
8909 : : {
8910 : : ListCell *lc;
8911 : :
8912 : : /*
8913 : : * Use any available suitably-sorted path as input, and also consider
8914 : : * sorting the cheapest partial path and incremental sort on any paths
8915 : : * with presorted keys.
8916 : : */
8917 [ + - + + : 3928 : foreach(lc, input_rel->partial_pathlist)
+ + ]
8918 : : {
8919 : 2042 : Path *input_path = (Path *) lfirst(lc);
8920 : : Path *path;
8921 : : bool is_sorted;
8922 : : int presorted_keys;
8923 : :
8924 : 2042 : is_sorted = pathkeys_count_contained_in(sortPathkeys,
8925 : : input_path->pathkeys,
8926 : : &presorted_keys);
8927 : :
8928 : : /*
8929 : : * Ignore paths that are not suitably or partially sorted, unless
8930 : : * they are the cheapest partial path (no need to deal with paths
8931 : : * which have presorted keys when incremental sort is disabled).
8932 : : */
8933 [ + + - + ]: 2042 : if (!is_sorted && input_path != cheapest_partial_path &&
208 rguo@postgresql.org 8934 [ # # # # ]:UNC 0 : (presorted_keys == 0 || !enable_incremental_sort))
8935 : 0 : continue;
8936 : :
8937 : : /*
8938 : : * Make a separate ProjectionPath in case we need a Result node.
8939 : : */
208 rguo@postgresql.org 8940 :GNC 2042 : path = (Path *) create_projection_path(root,
8941 : : partial_unique_rel,
8942 : : input_path,
8943 : 2042 : partial_unique_rel->reltarget);
8944 : :
8945 [ + + ]: 2042 : if (!is_sorted)
8946 : : {
8947 : : /*
8948 : : * We've no need to consider both a sort and incremental sort.
8949 : : * We'll just do a sort if there are no presorted keys and an
8950 : : * incremental sort when there are presorted keys.
8951 : : */
8952 [ - + - - ]: 1862 : if (presorted_keys == 0 || !enable_incremental_sort)
8953 : 1862 : path = (Path *) create_sort_path(root,
8954 : : partial_unique_rel,
8955 : : path,
8956 : : sortPathkeys,
8957 : : -1.0);
8958 : : else
208 rguo@postgresql.org 8959 :UNC 0 : path = (Path *) create_incremental_sort_path(root,
8960 : : partial_unique_rel,
8961 : : path,
8962 : : sortPathkeys,
8963 : : presorted_keys,
8964 : : -1.0);
8965 : : }
8966 : :
208 rguo@postgresql.org 8967 :GNC 2042 : path = (Path *) create_unique_path(root, partial_unique_rel, path,
8968 : : list_length(sortPathkeys),
8969 : : partial_unique_rel->rows);
8970 : :
8971 : 2042 : add_partial_path(partial_unique_rel, path);
8972 : : }
8973 : : }
8974 : :
8975 : : /* Consider hash-based implementation, if possible. */
8976 [ + - ]: 1886 : if (sjinfo->semi_can_hash)
8977 : : {
8978 : : Path *path;
8979 : :
8980 : : /*
8981 : : * Make a separate ProjectionPath in case we need a Result node.
8982 : : */
8983 : 1886 : path = (Path *) create_projection_path(root,
8984 : : partial_unique_rel,
8985 : : cheapest_partial_path,
8986 : 1886 : partial_unique_rel->reltarget);
8987 : :
8988 : 1886 : path = (Path *) create_agg_path(root,
8989 : : partial_unique_rel,
8990 : : path,
8991 : : cheapest_partial_path->pathtarget,
8992 : : AGG_HASHED,
8993 : : AGGSPLIT_SIMPLE,
8994 : : groupClause,
8995 : : NIL,
8996 : : NULL,
8997 : : partial_unique_rel->rows);
8998 : :
8999 : 1886 : add_partial_path(partial_unique_rel, path);
9000 : : }
9001 : :
9002 [ + - ]: 1886 : if (partial_unique_rel->partial_pathlist != NIL)
9003 : : {
9004 : 1886 : generate_useful_gather_paths(root, partial_unique_rel, true);
9005 : 1886 : set_cheapest(partial_unique_rel);
9006 : :
9007 : : /*
9008 : : * Finally, create paths to unique-ify the final result. This step is
9009 : : * needed to remove any duplicates due to combining rows from parallel
9010 : : * workers.
9011 : : */
9012 : 1886 : create_final_unique_paths(root, partial_unique_rel,
9013 : : sortPathkeys, groupClause,
9014 : : sjinfo, unique_rel);
9015 : : }
9016 : : }
9017 : :
9018 : : /*
9019 : : * Choose a unique name for some subroot.
9020 : : *
9021 : : * Modifies glob->subplanNames to track names already used.
9022 : : */
9023 : : char *
159 rhaas@postgresql.org 9024 : 47139 : choose_plan_name(PlannerGlobal *glob, const char *name, bool always_number)
9025 : : {
9026 : : unsigned n;
9027 : :
9028 : : /*
9029 : : * If a numeric suffix is not required, then search the list of
9030 : : * previously-assigned names for a match. If none is found, then we can
9031 : : * use the provided name without modification.
9032 : : */
9033 [ + + ]: 47139 : if (!always_number)
9034 : : {
9035 : 14894 : bool found = false;
9036 : :
9037 [ + + + + : 36460 : foreach_ptr(char, subplan_name, glob->subplanNames)
+ + ]
9038 : : {
9039 [ + + ]: 10405 : if (strcmp(subplan_name, name) == 0)
9040 : : {
9041 : 3733 : found = true;
9042 : 3733 : break;
9043 : : }
9044 : : }
9045 : :
9046 [ + + ]: 14894 : if (!found)
9047 : : {
9048 : : /* pstrdup here is just to avoid cast-away-const */
9049 : 11161 : char *chosen_name = pstrdup(name);
9050 : :
9051 : 11161 : glob->subplanNames = lappend(glob->subplanNames, chosen_name);
9052 : 11161 : return chosen_name;
9053 : : }
9054 : : }
9055 : :
9056 : : /*
9057 : : * If a numeric suffix is required or if the un-suffixed name is already
9058 : : * in use, then loop until we find a positive integer that produces a
9059 : : * novel name.
9060 : : */
9061 : 35978 : for (n = 1; true; ++n)
9062 : 33859 : {
9063 : 69837 : char *proposed_name = psprintf("%s_%u", name, n);
9064 : 69837 : bool found = false;
9065 : :
9066 [ + + + + : 278138 : foreach_ptr(char, subplan_name, glob->subplanNames)
+ + ]
9067 : : {
9068 [ + + ]: 172323 : if (strcmp(subplan_name, proposed_name) == 0)
9069 : : {
9070 : 33859 : found = true;
9071 : 33859 : break;
9072 : : }
9073 : : }
9074 : :
9075 [ + + ]: 69837 : if (!found)
9076 : : {
9077 : 35978 : glob->subplanNames = lappend(glob->subplanNames, proposed_name);
9078 : 35978 : return proposed_name;
9079 : : }
9080 : :
9081 : 33859 : pfree(proposed_name);
9082 : : }
9083 : : }
|
