Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * initsplan.c
4 : : * Target list, group by, qualification, joininfo initialization routines
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/initsplan.c
12 : : *
13 : : *-------------------------------------------------------------------------
14 : : */
15 : : #include "postgres.h"
16 : :
17 : : #include "access/nbtree.h"
18 : : #include "access/sysattr.h"
19 : : #include "catalog/pg_constraint.h"
20 : : #include "catalog/pg_type.h"
21 : : #include "nodes/makefuncs.h"
22 : : #include "nodes/nodeFuncs.h"
23 : : #include "optimizer/clauses.h"
24 : : #include "optimizer/cost.h"
25 : : #include "optimizer/inherit.h"
26 : : #include "optimizer/joininfo.h"
27 : : #include "optimizer/optimizer.h"
28 : : #include "optimizer/pathnode.h"
29 : : #include "optimizer/paths.h"
30 : : #include "optimizer/placeholder.h"
31 : : #include "optimizer/planmain.h"
32 : : #include "optimizer/planner.h"
33 : : #include "optimizer/restrictinfo.h"
34 : : #include "parser/analyze.h"
35 : : #include "rewrite/rewriteManip.h"
36 : : #include "utils/lsyscache.h"
37 : : #include "utils/rel.h"
38 : : #include "utils/typcache.h"
39 : :
40 : : /* These parameters are set by GUC */
41 : : int from_collapse_limit;
42 : : int join_collapse_limit;
43 : :
44 : :
45 : : /*
46 : : * deconstruct_jointree requires multiple passes over the join tree, because we
47 : : * need to finish computing JoinDomains before we start distributing quals.
48 : : * As long as we have to do that, other information such as the relevant
49 : : * qualscopes might as well be computed in the first pass too.
50 : : *
51 : : * deconstruct_recurse recursively examines the join tree and builds a List
52 : : * (in depth-first traversal order) of JoinTreeItem structs, which are then
53 : : * processed iteratively by deconstruct_distribute. If there are outer
54 : : * joins, non-degenerate outer join clauses are processed in a third pass
55 : : * deconstruct_distribute_oj_quals.
56 : : *
57 : : * The JoinTreeItem structs themselves can be freed at the end of
58 : : * deconstruct_jointree, but do not modify or free their substructure,
59 : : * as the relid sets may also be pointed to by RestrictInfo and
60 : : * SpecialJoinInfo nodes.
61 : : */
62 : : typedef struct JoinTreeItem
63 : : {
64 : : /* Fields filled during deconstruct_recurse: */
65 : : Node *jtnode; /* jointree node to examine */
66 : : JoinDomain *jdomain; /* join domain for its ON/WHERE clauses */
67 : : struct JoinTreeItem *jti_parent; /* JoinTreeItem for this node's
68 : : * parent, or NULL if it's the top */
69 : : Relids qualscope; /* base+OJ Relids syntactically included in
70 : : * this jointree node */
71 : : Relids inner_join_rels; /* base+OJ Relids syntactically included
72 : : * in inner joins appearing at or below
73 : : * this jointree node */
74 : : Relids left_rels; /* if join node, Relids of the left side */
75 : : Relids right_rels; /* if join node, Relids of the right side */
76 : : Relids nonnullable_rels; /* if outer join, Relids of the
77 : : * non-nullable side */
78 : : /* Fields filled during deconstruct_distribute: */
79 : : SpecialJoinInfo *sjinfo; /* if outer join, its SpecialJoinInfo */
80 : : List *oj_joinclauses; /* outer join quals not yet distributed */
81 : : List *lateral_clauses; /* quals postponed from children due to
82 : : * lateral references */
83 : : } JoinTreeItem;
84 : :
85 : : /*
86 : : * Compatibility info for one GROUP BY item, precomputed for use by
87 : : * remove_useless_groupby_columns() when matching unique-index columns against
88 : : * GROUP BY items.
89 : : */
90 : : typedef struct GroupByColInfo
91 : : {
92 : : AttrNumber attno; /* var->varattno */
93 : : List *eq_opfamilies; /* mergejoin opfamilies of sgc->eqop */
94 : : Oid coll; /* var->varcollid */
95 : : } GroupByColInfo;
96 : :
97 : :
98 : : static bool is_partial_agg_memory_risky(PlannerInfo *root);
99 : : static void create_agg_clause_infos(PlannerInfo *root);
100 : : static void create_grouping_expr_infos(PlannerInfo *root);
101 : : static EquivalenceClass *get_eclass_for_sortgroupclause(PlannerInfo *root,
102 : : SortGroupClause *sgc,
103 : : Expr *expr);
104 : : static void extract_lateral_references(PlannerInfo *root, RelOptInfo *brel,
105 : : Index rtindex);
106 : : static List *deconstruct_recurse(PlannerInfo *root, Node *jtnode,
107 : : JoinDomain *parent_domain,
108 : : JoinTreeItem *parent_jtitem,
109 : : List **item_list);
110 : : static void deconstruct_distribute(PlannerInfo *root, JoinTreeItem *jtitem);
111 : : static void process_security_barrier_quals(PlannerInfo *root,
112 : : int rti, JoinTreeItem *jtitem);
113 : : static void mark_rels_nulled_by_join(PlannerInfo *root, Index ojrelid,
114 : : Relids lower_rels);
115 : : static SpecialJoinInfo *make_outerjoininfo(PlannerInfo *root,
116 : : Relids left_rels, Relids right_rels,
117 : : Relids inner_join_rels,
118 : : JoinType jointype, Index ojrelid,
119 : : List *clause);
120 : : static void compute_semijoin_info(PlannerInfo *root, SpecialJoinInfo *sjinfo,
121 : : List *clause);
122 : : static void deconstruct_distribute_oj_quals(PlannerInfo *root,
123 : : List *jtitems,
124 : : JoinTreeItem *jtitem);
125 : : static void distribute_quals_to_rels(PlannerInfo *root, List *clauses,
126 : : JoinTreeItem *jtitem,
127 : : SpecialJoinInfo *sjinfo,
128 : : Index security_level,
129 : : Relids qualscope,
130 : : Relids ojscope,
131 : : Relids outerjoin_nonnullable,
132 : : Relids incompatible_relids,
133 : : bool allow_equivalence,
134 : : bool has_clone,
135 : : bool is_clone,
136 : : List **postponed_oj_qual_list);
137 : : static void distribute_qual_to_rels(PlannerInfo *root, Node *clause,
138 : : JoinTreeItem *jtitem,
139 : : SpecialJoinInfo *sjinfo,
140 : : Index security_level,
141 : : Relids qualscope,
142 : : Relids ojscope,
143 : : Relids outerjoin_nonnullable,
144 : : Relids incompatible_relids,
145 : : bool allow_equivalence,
146 : : bool has_clone,
147 : : bool is_clone,
148 : : List **postponed_oj_qual_list);
149 : : static bool check_redundant_nullability_qual(PlannerInfo *root, Node *clause);
150 : : static Relids get_join_domain_min_rels(PlannerInfo *root, Relids domain_relids);
151 : : static void check_mergejoinable(RestrictInfo *restrictinfo);
152 : : static void check_hashjoinable(RestrictInfo *restrictinfo);
153 : : static void check_memoizable(RestrictInfo *restrictinfo);
154 : :
155 : :
156 : : /*****************************************************************************
157 : : *
158 : : * JOIN TREES
159 : : *
160 : : *****************************************************************************/
161 : :
162 : : /*
163 : : * add_base_rels_to_query
164 : : *
165 : : * Scan the query's jointree and create baserel RelOptInfos for all
166 : : * the base relations (e.g., table, subquery, and function RTEs)
167 : : * appearing in the jointree.
168 : : *
169 : : * The initial invocation must pass root->parse->jointree as the value of
170 : : * jtnode. Internally, the function recurses through the jointree.
171 : : *
172 : : * At the end of this process, there should be one baserel RelOptInfo for
173 : : * every non-join RTE that is used in the query. Some of the baserels
174 : : * may be appendrel parents, which will require additional "otherrel"
175 : : * RelOptInfos for their member rels, but those are added later.
176 : : */
177 : : void
7664 tgl@sss.pgh.pa.us 178 :CBC 727342 : add_base_rels_to_query(PlannerInfo *root, Node *jtnode)
179 : : {
9391 180 [ - + ]: 727342 : if (jtnode == NULL)
8536 tgl@sss.pgh.pa.us 181 :UBC 0 : return;
9374 tgl@sss.pgh.pa.us 182 [ + + ]:CBC 727342 : if (IsA(jtnode, RangeTblRef))
183 : : {
184 : 376059 : int varno = ((RangeTblRef *) jtnode)->rtindex;
185 : :
3344 rhaas@postgresql.org 186 : 376059 : (void) build_simple_rel(root, varno, NULL);
187 : : }
9374 tgl@sss.pgh.pa.us 188 [ + + ]: 351283 : else if (IsA(jtnode, FromExpr))
189 : : {
190 : 268392 : FromExpr *f = (FromExpr *) jtnode;
191 : : ListCell *l;
192 : :
193 [ + - + + : 574456 : foreach(l, f->fromlist)
+ + ]
8536 194 : 306076 : add_base_rels_to_query(root, lfirst(l));
195 : : }
9391 196 [ + - ]: 82891 : else if (IsA(jtnode, JoinExpr))
197 : : {
198 : 82891 : JoinExpr *j = (JoinExpr *) jtnode;
199 : :
8536 200 : 82891 : add_base_rels_to_query(root, j->larg);
201 : 82891 : add_base_rels_to_query(root, j->rarg);
202 : : }
203 : : else
8345 tgl@sss.pgh.pa.us 204 [ # # ]:UBC 0 : elog(ERROR, "unrecognized node type: %d",
205 : : (int) nodeTag(jtnode));
206 : : }
207 : :
208 : : /*
209 : : * add_other_rels_to_query
210 : : * create "otherrel" RelOptInfos for the children of appendrel baserels
211 : : *
212 : : * At the end of this process, there should be RelOptInfos for all relations
213 : : * that will be scanned by the query.
214 : : */
215 : : void
2622 tgl@sss.pgh.pa.us 216 :CBC 255472 : add_other_rels_to_query(PlannerInfo *root)
217 : : {
218 : : int rti;
219 : :
220 [ + + ]: 800351 : for (rti = 1; rti < root->simple_rel_array_size; rti++)
221 : : {
222 : 544880 : RelOptInfo *rel = root->simple_rel_array[rti];
223 : 544880 : RangeTblEntry *rte = root->simple_rte_array[rti];
224 : :
225 : : /* there may be empty slots corresponding to non-baserel RTEs */
226 [ + + ]: 544880 : if (rel == NULL)
227 : 129294 : continue;
228 : :
229 : : /* Ignore any "otherrels" that were already added. */
230 [ + + ]: 415586 : if (rel->reloptkind != RELOPT_BASEREL)
231 : 48716 : continue;
232 : :
233 : : /* If it's marked as inheritable, look for children. */
234 [ + + ]: 366870 : if (rte->inh)
2618 235 : 17744 : expand_inherited_rtentry(root, rel, rte, rti);
236 : : }
2622 237 : 255471 : }
238 : :
239 : :
240 : : /*****************************************************************************
241 : : *
242 : : * TARGET LISTS
243 : : *
244 : : *****************************************************************************/
245 : :
246 : : /*
247 : : * build_base_rel_tlists
248 : : * Add targetlist entries for each var needed in the query's final tlist
249 : : * (and HAVING clause, if any) to the appropriate base relations.
250 : : *
251 : : * We mark such vars as needed by "relation 0" to ensure that they will
252 : : * propagate up through all join plan steps.
253 : : */
254 : : void
7664 255 : 255500 : build_base_rel_tlists(PlannerInfo *root, List *final_tlist)
256 : : {
6250 257 : 255500 : List *tlist_vars = pull_var_clause((Node *) final_tlist,
258 : : PVC_RECURSE_AGGREGATES |
259 : : PVC_RECURSE_WINDOWFUNCS |
260 : : PVC_INCLUDE_PLACEHOLDERS);
261 : :
8371 262 [ + + ]: 255500 : if (tlist_vars != NIL)
263 : : {
1382 264 : 239007 : add_vars_to_targetlist(root, tlist_vars, bms_make_singleton(0));
8035 neilc@samurai.com 265 : 239007 : list_free(tlist_vars);
266 : : }
267 : :
268 : : /*
269 : : * If there's a HAVING clause, we'll need the Vars it uses, too. Note
270 : : * that HAVING can contain Aggrefs but not WindowFuncs.
271 : : */
3796 tgl@sss.pgh.pa.us 272 [ + + ]: 255500 : if (root->parse->havingQual)
273 : : {
274 : 816 : List *having_vars = pull_var_clause(root->parse->havingQual,
275 : : PVC_RECURSE_AGGREGATES |
276 : : PVC_INCLUDE_PLACEHOLDERS);
277 : :
278 [ + + ]: 816 : if (having_vars != NIL)
279 : : {
280 : 716 : add_vars_to_targetlist(root, having_vars,
281 : : bms_make_singleton(0));
282 : 716 : list_free(having_vars);
283 : : }
284 : : }
8845 285 : 255500 : }
286 : :
287 : : /*
288 : : * add_vars_to_targetlist
289 : : * For each variable appearing in the list, add it to the owning
290 : : * relation's targetlist if not already present, and mark the variable
291 : : * as being needed for the indicated join (or for final output if
292 : : * where_needed includes "relation 0").
293 : : *
294 : : * The list may also contain PlaceHolderVars. These don't necessarily
295 : : * have a single owning relation; we keep their attr_needed info in
296 : : * root->placeholder_list instead. Find or create the associated
297 : : * PlaceHolderInfo entry, and update its ph_needed.
298 : : *
299 : : * See also add_vars_to_attr_needed.
300 : : */
301 : : void
5408 302 : 515036 : add_vars_to_targetlist(PlannerInfo *root, List *vars,
303 : : Relids where_needed)
304 : : {
305 : : ListCell *temp;
306 : :
8371 307 [ - + ]: 515036 : Assert(!bms_is_empty(where_needed));
308 : :
8845 309 [ + + + + : 1816399 : foreach(temp, vars)
+ + ]
310 : : {
6430 311 : 1301363 : Node *node = (Node *) lfirst(temp);
312 : :
313 [ + + ]: 1301363 : if (IsA(node, Var))
314 : : {
315 : 1298449 : Var *var = (Var *) node;
316 : 1298449 : RelOptInfo *rel = find_base_rel(root, var->varno);
317 : 1298449 : int attno = var->varattno;
318 : :
4669 319 [ + + ]: 1298449 : if (bms_is_subset(where_needed, rel->relids))
320 : 1382 : continue;
6430 321 [ + - - + ]: 1297067 : Assert(attno >= rel->min_attr && attno <= rel->max_attr);
322 : 1297067 : attno -= rel->min_attr;
323 [ + + ]: 1297067 : if (rel->attr_needed[attno] == NULL)
324 : : {
325 : : /*
326 : : * Variable not yet requested, so add to rel's targetlist.
327 : : *
328 : : * The value available at the rel's scan level has not been
329 : : * nulled by any outer join, so drop its varnullingrels.
330 : : * (We'll put those back as we climb up the join tree.)
331 : : */
1216 332 : 955630 : var = copyObject(var);
333 : 955630 : var->varnullingrels = NULL;
334 : 955630 : rel->reltarget->exprs = lappend(rel->reltarget->exprs, var);
335 : : /* reltarget cost and width will be computed later */
336 : : }
6430 337 : 1297067 : rel->attr_needed[attno] = bms_add_members(rel->attr_needed[attno],
338 : : where_needed);
339 : : }
340 [ + - ]: 2914 : else if (IsA(node, PlaceHolderVar))
341 : : {
342 : 2914 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1382 343 : 2914 : PlaceHolderInfo *phinfo = find_placeholder_info(root, phv);
344 : :
6430 345 : 2914 : phinfo->ph_needed = bms_add_members(phinfo->ph_needed,
346 : : where_needed);
347 : : }
348 : : else
6430 tgl@sss.pgh.pa.us 349 [ # # ]:UBC 0 : elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node));
350 : : }
8845 tgl@sss.pgh.pa.us 351 :CBC 515036 : }
352 : :
353 : : /*
354 : : * add_vars_to_attr_needed
355 : : * This does a subset of what add_vars_to_targetlist does: it just
356 : : * updates attr_needed for Vars and ph_needed for PlaceHolderVars.
357 : : * We assume the Vars are already in their relations' targetlists.
358 : : *
359 : : * This is used to rebuild attr_needed/ph_needed sets after removal
360 : : * of a useless outer join. The removed join clause might have been
361 : : * the only upper-level use of some other relation's Var, in which
362 : : * case we can reduce that Var's attr_needed and thereby possibly
363 : : * open the door to further join removals. But we can't tell that
364 : : * without tedious reconstruction of the attr_needed data.
365 : : *
366 : : * Note that if a Var's attr_needed is successfully reduced to empty,
367 : : * it will still be in the relation's targetlist even though we do
368 : : * not really need the scan plan node to emit it. The extra plan
369 : : * inefficiency seems tiny enough to not be worth spending planner
370 : : * cycles to get rid of it.
371 : : */
372 : : void
610 373 : 13240 : add_vars_to_attr_needed(PlannerInfo *root, List *vars,
374 : : Relids where_needed)
375 : : {
376 : : ListCell *temp;
377 : :
378 [ - + ]: 13240 : Assert(!bms_is_empty(where_needed));
379 : :
380 [ + + + + : 30361 : foreach(temp, vars)
+ + ]
381 : : {
382 : 17121 : Node *node = (Node *) lfirst(temp);
383 : :
384 [ + + ]: 17121 : if (IsA(node, Var))
385 : : {
386 : 17039 : Var *var = (Var *) node;
387 : 17039 : RelOptInfo *rel = find_base_rel(root, var->varno);
388 : 17039 : int attno = var->varattno;
389 : :
390 [ + + ]: 17039 : if (bms_is_subset(where_needed, rel->relids))
391 : 744 : continue;
392 [ + - - + ]: 16295 : Assert(attno >= rel->min_attr && attno <= rel->max_attr);
393 : 16295 : attno -= rel->min_attr;
394 : 16295 : rel->attr_needed[attno] = bms_add_members(rel->attr_needed[attno],
395 : : where_needed);
396 : : }
397 [ + - ]: 82 : else if (IsA(node, PlaceHolderVar))
398 : : {
399 : 82 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
400 : 82 : PlaceHolderInfo *phinfo = find_placeholder_info(root, phv);
401 : :
402 : 82 : phinfo->ph_needed = bms_add_members(phinfo->ph_needed,
403 : : where_needed);
404 : : }
405 : : else
610 tgl@sss.pgh.pa.us 406 [ # # ]:UBC 0 : elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node));
407 : : }
610 tgl@sss.pgh.pa.us 408 :CBC 13240 : }
409 : :
410 : : /*****************************************************************************
411 : : *
412 : : * GROUP BY
413 : : *
414 : : *****************************************************************************/
415 : :
416 : : /*
417 : : * remove_useless_groupby_columns
418 : : * Remove any columns in the GROUP BY clause that are redundant due to
419 : : * being functionally dependent on other GROUP BY columns.
420 : : *
421 : : * Since some other DBMSes do not allow references to ungrouped columns, it's
422 : : * not unusual to find all columns listed in GROUP BY even though listing the
423 : : * primary-key columns, or columns of a unique constraint would be sufficient.
424 : : * Deleting such excess columns avoids redundant sorting or hashing work, so
425 : : * it's worth doing.
426 : : *
427 : : * Relcache invalidations will ensure that cached plans become invalidated
428 : : * when the underlying supporting indexes are dropped or if a column's NOT
429 : : * NULL attribute is removed.
430 : : */
431 : : void
534 drowley@postgresql.o 432 : 255472 : remove_useless_groupby_columns(PlannerInfo *root)
433 : : {
434 : 255472 : Query *parse = root->parse;
435 : : Bitmapset **groupbyattnos;
436 : : List **groupbycols;
437 : : Bitmapset **surplusvars;
438 : 255472 : bool tryremove = false;
439 : : ListCell *lc;
440 : : int relid;
441 : :
442 : : /* No chance to do anything if there are less than two GROUP BY items */
443 [ + + ]: 255472 : if (list_length(root->processed_groupClause) < 2)
444 : 253594 : return;
445 : :
446 : : /* Don't fiddle with the GROUP BY clause if the query has grouping sets */
447 [ + + ]: 1878 : if (parse->groupingSets)
448 : 673 : return;
449 : :
450 : : /*
451 : : * Scan the GROUP BY clause to find GROUP BY items that are simple Vars.
452 : : * Fill groupbyattnos[k] with a bitmapset of the column attnos of RTE k
453 : : * that are GROUP BY items, and groupbycols[k] with a parallel list of
454 : : * GroupByColInfo records. We need the latter so that, when checking a
455 : : * unique index against this rel's GROUP BY items, we can verify that the
456 : : * index's notion of equality agrees with at least one GROUP BY item per
457 : : * index column.
458 : : */
171 michael@paquier.xyz 459 :GNC 1205 : groupbyattnos = palloc0_array(Bitmapset *, list_length(parse->rtable) + 1);
22 rguo@postgresql.org 460 :CBC 1205 : groupbycols = palloc0_array(List *, list_length(parse->rtable) + 1);
534 drowley@postgresql.o 461 [ + - + + : 4355 : foreach(lc, root->processed_groupClause)
+ + ]
462 : : {
463 : 3150 : SortGroupClause *sgc = lfirst_node(SortGroupClause, lc);
464 : 3150 : TargetEntry *tle = get_sortgroupclause_tle(sgc, parse->targetList);
465 : 3150 : Var *var = (Var *) tle->expr;
466 : : GroupByColInfo *info;
467 : :
468 : : /*
469 : : * Ignore non-Vars and Vars from other query levels.
470 : : *
471 : : * XXX in principle, stable expressions containing Vars could also be
472 : : * removed, if all the Vars are functionally dependent on other GROUP
473 : : * BY items. But it's not clear that such cases occur often enough to
474 : : * be worth troubling over.
475 : : */
476 [ + + ]: 3150 : if (!IsA(var, Var) ||
477 [ - + ]: 2487 : var->varlevelsup > 0)
478 : 663 : continue;
479 : :
480 : : /* OK, remember we have this Var */
481 : 2487 : relid = var->varno;
482 [ - + ]: 2487 : Assert(relid <= list_length(parse->rtable));
483 : :
484 : : /*
485 : : * If this isn't the first column for this relation then we now have
486 : : * multiple columns. That means there might be some that can be
487 : : * removed.
488 : : */
489 : 2487 : tryremove |= !bms_is_empty(groupbyattnos[relid]);
490 : 4974 : groupbyattnos[relid] = bms_add_member(groupbyattnos[relid],
491 : 2487 : var->varattno - FirstLowInvalidHeapAttributeNumber);
492 : :
22 rguo@postgresql.org 493 : 2487 : info = palloc(sizeof(GroupByColInfo));
494 : 2487 : info->attno = var->varattno;
495 : 2487 : info->eq_opfamilies = get_mergejoin_opfamilies(sgc->eqop);
496 : 2487 : info->coll = var->varcollid;
497 : 2487 : groupbycols[relid] = lappend(groupbycols[relid], info);
498 : : }
499 : :
500 : : /*
501 : : * No Vars or didn't find multiple Vars for any relation in the GROUP BY?
502 : : * If so, nothing can be removed, so don't waste more effort trying.
503 : : */
534 drowley@postgresql.o 504 [ + + ]: 1205 : if (!tryremove)
505 : 366 : return;
506 : :
507 : : /*
508 : : * Consider each relation and see if it is possible to remove some of its
509 : : * Vars from GROUP BY. For simplicity and speed, we do the actual removal
510 : : * in a separate pass. Here, we just fill surplusvars[k] with a bitmapset
511 : : * of the column attnos of RTE k that are removable GROUP BY items.
512 : : */
513 : 839 : surplusvars = NULL; /* don't allocate array unless required */
514 : 839 : relid = 0;
515 [ + - + + : 3516 : foreach(lc, parse->rtable)
+ + ]
516 : : {
517 : 2677 : RangeTblEntry *rte = lfirst_node(RangeTblEntry, lc);
518 : : RelOptInfo *rel;
519 : : Bitmapset *relattnos;
520 : 2677 : Bitmapset *best_keycolumns = NULL;
521 : 2677 : int32 best_nkeycolumns = PG_INT32_MAX;
522 : :
523 : 2677 : relid++;
524 : :
525 : : /* Only plain relations could have primary-key constraints */
526 [ + + ]: 2677 : if (rte->rtekind != RTE_RELATION)
527 : 1361 : continue;
528 : :
529 : : /*
530 : : * We must skip inheritance parent tables as some of the child rels
531 : : * may cause duplicate rows. This cannot happen with partitioned
532 : : * tables, however.
533 : : */
534 [ + + + + ]: 1316 : if (rte->inh && rte->relkind != RELKIND_PARTITIONED_TABLE)
535 : 15 : continue;
536 : :
537 : : /* Nothing to do unless this rel has multiple Vars in GROUP BY */
538 : 1301 : relattnos = groupbyattnos[relid];
539 [ + + ]: 1301 : if (bms_membership(relattnos) != BMS_MULTIPLE)
540 : 490 : continue;
541 : :
542 : 811 : rel = root->simple_rel_array[relid];
543 : :
544 : : /*
545 : : * Now check each index for this relation to see if there are any with
546 : : * columns which are a proper subset of the grouping columns for this
547 : : * relation.
548 : : */
549 [ + + + + : 2511 : foreach_node(IndexOptInfo, index, rel->indexlist)
+ + ]
550 : : {
551 : : Bitmapset *ind_attnos;
552 : : bool index_check_ok;
553 : :
554 : : /*
555 : : * Skip any non-unique and deferrable indexes. Predicate indexes
556 : : * have not been checked yet, so we must skip those too as the
557 : : * predOK check that's done later might fail.
558 : : */
559 [ + + + + : 889 : if (!index->unique || !index->immediate || index->indpred != NIL)
- + ]
560 : 341 : continue;
561 : :
562 : : /* For simplicity, we currently don't support expression indexes */
563 [ - + ]: 548 : if (index->indexprs != NIL)
534 drowley@postgresql.o 564 :UBC 0 : continue;
565 : :
534 drowley@postgresql.o 566 :CBC 548 : ind_attnos = NULL;
22 rguo@postgresql.org 567 : 548 : index_check_ok = true;
534 drowley@postgresql.o 568 [ + + ]: 1096 : for (int i = 0; i < index->nkeycolumns; i++)
569 : : {
22 rguo@postgresql.org 570 : 809 : AttrNumber indkey_attno = index->indexkeys[i];
571 : 809 : Oid indkey_opfamily = index->opfamily[i];
572 : 809 : Oid indkey_coll = index->indexcollations[i];
573 : : ListCell *lc2;
574 : :
575 : : /*
576 : : * We must insist that the index columns are all defined NOT
577 : : * NULL otherwise duplicate NULLs could exist. However, we
578 : : * can relax this check when the index is defined with NULLS
579 : : * NOT DISTINCT as there can only be 1 NULL row, therefore
580 : : * functional dependency on the unique columns is maintained,
581 : : * despite the NULL.
582 : : */
534 drowley@postgresql.o 583 [ + + ]: 809 : if (!index->nullsnotdistinct &&
22 rguo@postgresql.org 584 [ + + ]: 804 : !bms_is_member(indkey_attno, rel->notnullattnums))
585 : : {
586 : 5 : index_check_ok = false;
587 : 5 : break;
588 : : }
589 : :
590 : : /*
591 : : * The index proves uniqueness only under its own opfamily and
592 : : * collation. Require some GROUP BY item on this column to
593 : : * use a compatible eqop and collation, the same check
594 : : * relation_has_unique_index_for() applies to join clauses.
595 : : */
596 [ + - + + : 1607 : foreach(lc2, groupbycols[relid])
+ + ]
597 : : {
598 : 1351 : GroupByColInfo *info = (GroupByColInfo *) lfirst(lc2);
599 : :
600 [ + + ]: 1351 : if (info->attno != indkey_attno)
601 : 783 : continue;
602 [ + + + + ]: 1126 : if (list_member_oid(info->eq_opfamilies, indkey_opfamily) &&
603 : 558 : collations_agree_on_equality(indkey_coll, info->coll))
604 : 548 : break;
605 : : }
606 [ + + ]: 804 : if (lc2 == NULL)
607 : : {
608 : 256 : index_check_ok = false;
534 drowley@postgresql.o 609 : 256 : break;
610 : : }
611 : :
612 : : ind_attnos =
613 : 548 : bms_add_member(ind_attnos,
614 : : indkey_attno -
615 : : FirstLowInvalidHeapAttributeNumber);
616 : : }
617 : :
22 rguo@postgresql.org 618 [ + + ]: 548 : if (!index_check_ok)
534 drowley@postgresql.o 619 : 261 : continue;
620 : :
621 : : /*
622 : : * Skip any indexes where the indexed columns aren't a proper
623 : : * subset of the GROUP BY.
624 : : */
625 [ + + ]: 287 : if (bms_subset_compare(ind_attnos, relattnos) != BMS_SUBSET1)
626 : 5 : continue;
627 : :
628 : : /*
629 : : * Record the attribute numbers from the index with the fewest
630 : : * columns. This allows the largest number of columns to be
631 : : * removed from the GROUP BY clause. In the future, we may wish
632 : : * to consider using the narrowest set of columns and looking at
633 : : * pg_statistic.stawidth as it might be better to use an index
634 : : * with, say two INT4s, rather than, say, one long varlena column.
635 : : */
636 [ + + ]: 282 : if (index->nkeycolumns < best_nkeycolumns)
637 : : {
638 : 267 : best_keycolumns = ind_attnos;
639 : 267 : best_nkeycolumns = index->nkeycolumns;
640 : : }
641 : : }
642 : :
643 : : /* Did we find a suitable index? */
644 [ + + ]: 811 : if (!bms_is_empty(best_keycolumns))
645 : : {
646 : : /*
647 : : * To easily remember whether we've found anything to do, we don't
648 : : * allocate the surplusvars[] array until we find something.
649 : : */
650 [ + + ]: 267 : if (surplusvars == NULL)
171 michael@paquier.xyz 651 :GNC 262 : surplusvars = palloc0_array(Bitmapset *, list_length(parse->rtable) + 1);
652 : :
653 : : /* Remember the attnos of the removable columns */
534 drowley@postgresql.o 654 :CBC 267 : surplusvars[relid] = bms_difference(relattnos, best_keycolumns);
655 : : }
656 : : }
657 : :
658 : : /*
659 : : * If we found any surplus Vars, build a new GROUP BY clause without them.
660 : : * (Note: this may leave some TLEs with unreferenced ressortgroupref
661 : : * markings, but that's harmless.)
662 : : */
663 [ + + ]: 839 : if (surplusvars != NULL)
664 : : {
665 : 262 : List *new_groupby = NIL;
666 : :
667 [ + - + + : 1077 : foreach(lc, root->processed_groupClause)
+ + ]
668 : : {
669 : 815 : SortGroupClause *sgc = lfirst_node(SortGroupClause, lc);
670 : 815 : TargetEntry *tle = get_sortgroupclause_tle(sgc, parse->targetList);
671 : 815 : Var *var = (Var *) tle->expr;
672 : :
673 : : /*
674 : : * New list must include non-Vars, outer Vars, and anything not
675 : : * marked as surplus.
676 : : */
677 [ + - ]: 815 : if (!IsA(var, Var) ||
678 [ + - ]: 815 : var->varlevelsup > 0 ||
679 [ + + ]: 815 : !bms_is_member(var->varattno - FirstLowInvalidHeapAttributeNumber,
680 : 815 : surplusvars[var->varno]))
681 : 513 : new_groupby = lappend(new_groupby, sgc);
682 : : }
683 : :
684 : 262 : root->processed_groupClause = new_groupby;
685 : : }
686 : : }
687 : :
688 : : /*
689 : : * setup_eager_aggregation
690 : : * Check if eager aggregation is applicable, and if so collect suitable
691 : : * aggregate expressions and grouping expressions in the query.
692 : : */
693 : : void
234 rguo@postgresql.org 694 :GNC 255472 : setup_eager_aggregation(PlannerInfo *root)
695 : : {
696 : : /*
697 : : * Don't apply eager aggregation if disabled by user.
698 : : */
699 [ + + ]: 255472 : if (!enable_eager_aggregate)
700 : 400 : return;
701 : :
702 : : /*
703 : : * Don't apply eager aggregation if there are no available GROUP BY
704 : : * clauses.
705 : : */
706 [ + + ]: 255072 : if (!root->processed_groupClause)
707 : 251320 : return;
708 : :
709 : : /*
710 : : * For now we don't try to support grouping sets.
711 : : */
712 [ + + ]: 3752 : if (root->parse->groupingSets)
713 : 757 : return;
714 : :
715 : : /*
716 : : * For now we don't try to support DISTINCT or ORDER BY aggregates.
717 : : */
718 [ + + ]: 2995 : if (root->numOrderedAggs > 0)
719 : 152 : return;
720 : :
721 : : /*
722 : : * If there are any aggregates that do not support partial mode, or any
723 : : * partial aggregates that are non-serializable, do not apply eager
724 : : * aggregation.
725 : : */
726 [ + + - + ]: 2843 : if (root->hasNonPartialAggs || root->hasNonSerialAggs)
727 : 125 : return;
728 : :
729 : : /*
730 : : * We don't try to apply eager aggregation if there are set-returning
731 : : * functions in targetlist.
732 : : */
733 [ + + ]: 2718 : if (root->parse->hasTargetSRFs)
734 : 70 : return;
735 : :
736 : : /*
737 : : * Eager aggregation only makes sense if there are multiple base rels in
738 : : * the query.
739 : : */
740 [ + + ]: 2648 : if (bms_membership(root->all_baserels) != BMS_MULTIPLE)
741 : 1812 : return;
742 : :
743 : : /*
744 : : * Don't apply eager aggregation if any aggregate poses a risk of
745 : : * excessive memory usage during partial aggregation.
746 : : */
747 [ + + ]: 836 : if (is_partial_agg_memory_risky(root))
748 : 1 : return;
749 : :
750 : : /*
751 : : * Collect aggregate expressions and plain Vars that appear in the
752 : : * targetlist and havingQual.
753 : : */
754 : 835 : create_agg_clause_infos(root);
755 : :
756 : : /*
757 : : * If there are no suitable aggregate expressions, we cannot apply eager
758 : : * aggregation.
759 : : */
760 [ + + ]: 835 : if (root->agg_clause_list == NIL)
761 : 284 : return;
762 : :
763 : : /*
764 : : * Collect grouping expressions that appear in grouping clauses.
765 : : */
766 : 551 : create_grouping_expr_infos(root);
767 : : }
768 : :
769 : : /*
770 : : * is_partial_agg_memory_risky
771 : : * Check if any aggregate poses a risk of excessive memory usage during
772 : : * partial aggregation.
773 : : *
774 : : * We check if any aggregate has a negative aggtransspace value, which
775 : : * indicates that its transition state data can grow unboundedly in size.
776 : : * Applying eager aggregation in such cases risks high memory usage since
777 : : * partial aggregation results might be stored in join hash tables or
778 : : * materialized nodes.
779 : : */
780 : : static bool
781 : 836 : is_partial_agg_memory_risky(PlannerInfo *root)
782 : : {
783 : : ListCell *lc;
784 : :
785 [ + + + + : 1608 : foreach(lc, root->aggtransinfos)
+ + ]
786 : : {
787 : 773 : AggTransInfo *transinfo = lfirst_node(AggTransInfo, lc);
788 : :
789 [ + + ]: 773 : if (transinfo->aggtransspace < 0)
790 : 1 : return true;
791 : : }
792 : :
793 : 835 : return false;
794 : : }
795 : :
796 : : /*
797 : : * create_agg_clause_infos
798 : : * Search the targetlist and havingQual for Aggrefs and plain Vars, and
799 : : * create an AggClauseInfo for each Aggref node.
800 : : */
801 : : static void
802 : 835 : create_agg_clause_infos(PlannerInfo *root)
803 : : {
804 : : List *tlist_exprs;
805 : 835 : List *agg_clause_list = NIL;
806 : 835 : List *tlist_vars = NIL;
807 : 835 : Relids aggregate_relids = NULL;
808 : 835 : bool eager_agg_applicable = true;
809 : : ListCell *lc;
810 : :
811 [ - + ]: 835 : Assert(root->agg_clause_list == NIL);
812 [ - + ]: 835 : Assert(root->tlist_vars == NIL);
813 : :
814 : 835 : tlist_exprs = pull_var_clause((Node *) root->processed_tlist,
815 : : PVC_INCLUDE_AGGREGATES |
816 : : PVC_RECURSE_WINDOWFUNCS |
817 : : PVC_RECURSE_PLACEHOLDERS);
818 : :
819 : : /*
820 : : * Aggregates within the HAVING clause need to be processed in the same
821 : : * way as those in the targetlist. Note that HAVING can contain Aggrefs
822 : : * but not WindowFuncs.
823 : : */
824 [ + + ]: 835 : if (root->parse->havingQual != NULL)
825 : : {
826 : : List *having_exprs;
827 : :
828 : 35 : having_exprs = pull_var_clause((Node *) root->parse->havingQual,
829 : : PVC_INCLUDE_AGGREGATES |
830 : : PVC_RECURSE_PLACEHOLDERS);
831 [ + - ]: 35 : if (having_exprs != NIL)
832 : : {
833 : 35 : tlist_exprs = list_concat(tlist_exprs, having_exprs);
834 : 35 : list_free(having_exprs);
835 : : }
836 : : }
837 : :
838 [ + - + + : 3691 : foreach(lc, tlist_exprs)
+ + ]
839 : : {
840 : 2904 : Expr *expr = (Expr *) lfirst(lc);
841 : : Aggref *aggref;
842 : : Relids agg_eval_at;
843 : : AggClauseInfo *ac_info;
844 : :
845 : : /* For now we don't try to support GROUPING() expressions */
846 [ - + ]: 2904 : if (IsA(expr, GroupingFunc))
847 : : {
234 rguo@postgresql.org 848 :UNC 0 : eager_agg_applicable = false;
849 : 0 : break;
850 : : }
851 : :
852 : : /* Collect plain Vars for future reference */
234 rguo@postgresql.org 853 [ + + ]:GNC 2904 : if (IsA(expr, Var))
854 : : {
855 : 2127 : tlist_vars = list_append_unique(tlist_vars, expr);
856 : 2127 : continue;
857 : : }
858 : :
859 : 777 : aggref = castNode(Aggref, expr);
860 : :
861 [ - + ]: 777 : Assert(aggref->aggorder == NIL);
862 [ - + ]: 777 : Assert(aggref->aggdistinct == NIL);
863 : :
864 : : /*
865 : : * We cannot push down aggregates that contain volatile functions.
866 : : * Doing so would change the number of times the function is
867 : : * evaluated.
868 : : */
54 869 [ + + ]: 777 : if (contain_volatile_functions((Node *) aggref))
870 : : {
871 : 10 : eager_agg_applicable = false;
872 : 10 : break;
873 : : }
874 : :
875 : : /*
876 : : * If there are any securityQuals, do not try to apply eager
877 : : * aggregation if any non-leakproof aggregate functions are present.
878 : : * This is overly strict, but for now...
879 : : */
234 880 [ - + ]: 767 : if (root->qual_security_level > 0 &&
234 rguo@postgresql.org 881 [ # # ]:UNC 0 : !get_func_leakproof(aggref->aggfnoid))
882 : : {
883 : 0 : eager_agg_applicable = false;
884 : 0 : break;
885 : : }
886 : :
234 rguo@postgresql.org 887 :GNC 767 : agg_eval_at = pull_varnos(root, (Node *) aggref);
888 : :
889 : : /*
890 : : * If all base relations in the query are referenced by aggregate
891 : : * functions, then eager aggregation is not applicable.
892 : : */
893 : 767 : aggregate_relids = bms_add_members(aggregate_relids, agg_eval_at);
894 [ + + ]: 767 : if (bms_is_subset(root->all_baserels, aggregate_relids))
895 : : {
896 : 38 : eager_agg_applicable = false;
897 : 38 : break;
898 : : }
899 : :
900 : : /* OK, create the AggClauseInfo node */
901 : 729 : ac_info = makeNode(AggClauseInfo);
902 : 729 : ac_info->aggref = aggref;
903 : 729 : ac_info->agg_eval_at = agg_eval_at;
904 : :
905 : : /* ... and add it to the list */
906 : 729 : agg_clause_list = list_append_unique(agg_clause_list, ac_info);
907 : : }
908 : :
909 : 835 : list_free(tlist_exprs);
910 : :
911 [ + + ]: 835 : if (eager_agg_applicable)
912 : : {
913 : 787 : root->agg_clause_list = agg_clause_list;
914 : 787 : root->tlist_vars = tlist_vars;
915 : : }
916 : : else
917 : : {
918 : 48 : list_free_deep(agg_clause_list);
919 : 48 : list_free(tlist_vars);
920 : : }
921 : 835 : }
922 : :
923 : : /*
924 : : * create_grouping_expr_infos
925 : : * Create a GroupingExprInfo for each expression usable as grouping key.
926 : : *
927 : : * If any grouping expression is not suitable, we will just return with
928 : : * root->group_expr_list being NIL.
929 : : */
930 : : static void
931 : 551 : create_grouping_expr_infos(PlannerInfo *root)
932 : : {
933 : 551 : List *exprs = NIL;
934 : 551 : List *sortgrouprefs = NIL;
935 : 551 : List *ecs = NIL;
936 : : ListCell *lc,
937 : : *lc1,
938 : : *lc2,
939 : : *lc3;
940 : :
941 [ - + ]: 551 : Assert(root->group_expr_list == NIL);
942 : :
943 [ + - + + : 1047 : foreach(lc, root->processed_groupClause)
+ + ]
944 : : {
945 : 607 : SortGroupClause *sgc = lfirst_node(SortGroupClause, lc);
946 : 607 : TargetEntry *tle = get_sortgroupclause_tle(sgc, root->processed_tlist);
947 : : TypeCacheEntry *tce;
948 : : Oid equalimageproc;
949 : :
950 [ - + ]: 607 : Assert(tle->ressortgroupref > 0);
951 : :
952 : : /*
953 : : * For now we only support plain Vars as grouping expressions.
954 : : */
955 [ + + ]: 607 : if (!IsA(tle->expr, Var))
956 : 111 : return;
957 : :
958 : : /*
959 : : * Eager aggregation is only possible if equality implies image
960 : : * equality for each grouping key. Otherwise, placing keys with
961 : : * different byte images into the same group may result in the loss of
962 : : * information that could be necessary to evaluate upper qual clauses.
963 : : *
964 : : * For instance, the NUMERIC data type is not supported, as values
965 : : * that are considered equal by the equality operator (e.g., 0 and
966 : : * 0.0) can have different scales.
967 : : */
968 : 561 : tce = lookup_type_cache(exprType((Node *) tle->expr),
969 : : TYPECACHE_BTREE_OPFAMILY);
970 [ + - ]: 561 : if (!OidIsValid(tce->btree_opf) ||
971 [ - + ]: 561 : !OidIsValid(tce->btree_opintype))
234 rguo@postgresql.org 972 :UNC 0 : return;
973 : :
234 rguo@postgresql.org 974 :GNC 561 : equalimageproc = get_opfamily_proc(tce->btree_opf,
975 : : tce->btree_opintype,
976 : : tce->btree_opintype,
977 : : BTEQUALIMAGE_PROC);
978 : :
979 : : /*
980 : : * If there is no BTEQUALIMAGE_PROC, eager aggregation is assumed to
981 : : * be unsafe. Otherwise, we call the procedure to check. We must be
982 : : * careful to pass the expression's actual collation, rather than the
983 : : * data type's default collation, to ensure that non-deterministic
984 : : * collations are correctly handled.
985 : : */
986 [ + + ]: 561 : if (!OidIsValid(equalimageproc) ||
987 [ + + ]: 1112 : !DatumGetBool(OidFunctionCall1Coll(equalimageproc,
54 988 : 556 : exprCollation((Node *) tle->expr),
989 : : ObjectIdGetDatum(tce->btree_opintype))))
234 990 : 65 : return;
991 : :
992 : 496 : exprs = lappend(exprs, tle->expr);
993 : 496 : sortgrouprefs = lappend_int(sortgrouprefs, tle->ressortgroupref);
994 : 496 : ecs = lappend(ecs, get_eclass_for_sortgroupclause(root, sgc, tle->expr));
995 : : }
996 : :
997 : : /*
998 : : * Construct a GroupingExprInfo for each expression.
999 : : */
1000 : 916 : forthree(lc1, exprs, lc2, sortgrouprefs, lc3, ecs)
[ + - + +
+ - + + +
- + + + +
+ - + - +
+ ]
1001 : : {
1002 : 476 : Expr *expr = (Expr *) lfirst(lc1);
1003 : 476 : int sortgroupref = lfirst_int(lc2);
1004 : 476 : EquivalenceClass *ec = (EquivalenceClass *) lfirst(lc3);
1005 : : GroupingExprInfo *ge_info;
1006 : :
1007 : 476 : ge_info = makeNode(GroupingExprInfo);
1008 : 476 : ge_info->expr = (Expr *) copyObject(expr);
1009 : 476 : ge_info->sortgroupref = sortgroupref;
1010 : 476 : ge_info->ec = ec;
1011 : :
1012 : 476 : root->group_expr_list = lappend(root->group_expr_list, ge_info);
1013 : : }
1014 : : }
1015 : :
1016 : : /*
1017 : : * get_eclass_for_sortgroupclause
1018 : : * Given a group clause and an expression, find an existing equivalence
1019 : : * class that the expression is a member of; return NULL if none.
1020 : : */
1021 : : static EquivalenceClass *
1022 : 496 : get_eclass_for_sortgroupclause(PlannerInfo *root, SortGroupClause *sgc,
1023 : : Expr *expr)
1024 : : {
1025 : : Oid opfamily,
1026 : : opcintype,
1027 : : collation;
1028 : : CompareType cmptype;
1029 : : Oid equality_op;
1030 : : List *opfamilies;
1031 : :
1032 : : /* Punt if the group clause is not sortable */
1033 [ - + ]: 496 : if (!OidIsValid(sgc->sortop))
234 rguo@postgresql.org 1034 :UNC 0 : return NULL;
1035 : :
1036 : : /* Find the operator in pg_amop --- failure shouldn't happen */
234 rguo@postgresql.org 1037 [ - + ]:GNC 496 : if (!get_ordering_op_properties(sgc->sortop,
1038 : : &opfamily, &opcintype, &cmptype))
234 rguo@postgresql.org 1039 [ # # ]:UNC 0 : elog(ERROR, "operator %u is not a valid ordering operator",
1040 : : sgc->sortop);
1041 : :
1042 : : /* Because SortGroupClause doesn't carry collation, consult the expr */
234 rguo@postgresql.org 1043 :GNC 496 : collation = exprCollation((Node *) expr);
1044 : :
1045 : : /*
1046 : : * EquivalenceClasses need to contain opfamily lists based on the family
1047 : : * membership of mergejoinable equality operators, which could belong to
1048 : : * more than one opfamily. So we have to look up the opfamily's equality
1049 : : * operator and get its membership.
1050 : : */
1051 : 496 : equality_op = get_opfamily_member_for_cmptype(opfamily,
1052 : : opcintype,
1053 : : opcintype,
1054 : : COMPARE_EQ);
1055 [ - + ]: 496 : if (!OidIsValid(equality_op)) /* shouldn't happen */
234 rguo@postgresql.org 1056 [ # # ]:UNC 0 : elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
1057 : : COMPARE_EQ, opcintype, opcintype, opfamily);
234 rguo@postgresql.org 1058 :GNC 496 : opfamilies = get_mergejoin_opfamilies(equality_op);
1059 [ - + ]: 496 : if (!opfamilies) /* certainly should find some */
234 rguo@postgresql.org 1060 [ # # ]:UNC 0 : elog(ERROR, "could not find opfamilies for equality operator %u",
1061 : : equality_op);
1062 : :
1063 : : /* Now find a matching EquivalenceClass */
234 rguo@postgresql.org 1064 :GNC 496 : return get_eclass_for_sort_expr(root, expr, opfamilies, opcintype,
1065 : : collation, sgc->tleSortGroupRef,
1066 : : NULL, false);
1067 : : }
1068 : :
1069 : : /*****************************************************************************
1070 : : *
1071 : : * LATERAL REFERENCES
1072 : : *
1073 : : *****************************************************************************/
1074 : :
1075 : : /*
1076 : : * find_lateral_references
1077 : : * For each LATERAL subquery, extract all its references to Vars and
1078 : : * PlaceHolderVars of the current query level, and make sure those values
1079 : : * will be available for evaluation of the subquery.
1080 : : *
1081 : : * While later planning steps ensure that the Var/PHV source rels are on the
1082 : : * outside of nestloops relative to the LATERAL subquery, we also need to
1083 : : * ensure that the Vars/PHVs propagate up to the nestloop join level; this
1084 : : * means setting suitable where_needed values for them.
1085 : : *
1086 : : * Note that this only deals with lateral references in unflattened LATERAL
1087 : : * subqueries. When we flatten a LATERAL subquery, its lateral references
1088 : : * become plain Vars in the parent query, but they may have to be wrapped in
1089 : : * PlaceHolderVars if they need to be forced NULL by outer joins that don't
1090 : : * also null the LATERAL subquery. That's all handled elsewhere.
1091 : : *
1092 : : * This has to run before deconstruct_jointree, since it might result in
1093 : : * creation of PlaceHolderInfos.
1094 : : */
1095 : : void
5025 tgl@sss.pgh.pa.us 1096 :CBC 255472 : find_lateral_references(PlannerInfo *root)
1097 : : {
1098 : : Index rti;
1099 : :
1100 : : /* We need do nothing if the query contains no LATERAL RTEs */
1101 [ + + ]: 255472 : if (!root->hasLateralRTEs)
1102 : 248559 : return;
1103 : :
1104 : : /*
1105 : : * Examine all baserels (the rel array has been set up by now).
1106 : : */
1107 [ + + ]: 32905 : for (rti = 1; rti < root->simple_rel_array_size; rti++)
1108 : : {
1109 : 25992 : RelOptInfo *brel = root->simple_rel_array[rti];
1110 : :
1111 : : /* there may be empty slots corresponding to non-baserel RTEs */
1112 [ + + ]: 25992 : if (brel == NULL)
1113 : 8648 : continue;
1114 : :
3265 1115 [ - + ]: 17344 : Assert(brel->relid == rti); /* sanity check on array */
1116 : :
1117 : : /*
1118 : : * This bit is less obvious than it might look. We ignore appendrel
1119 : : * otherrels and consider only their parent baserels. In a case where
1120 : : * a LATERAL-containing UNION ALL subquery was pulled up, it is the
1121 : : * otherrel that is actually going to be in the plan. However, we
1122 : : * want to mark all its lateral references as needed by the parent,
1123 : : * because it is the parent's relid that will be used for join
1124 : : * planning purposes. And the parent's RTE will contain all the
1125 : : * lateral references we need to know, since the pulled-up member is
1126 : : * nothing but a copy of parts of the original RTE's subquery. We
1127 : : * could visit the parent's children instead and transform their
1128 : : * references back to the parent's relid, but it would be much more
1129 : : * complicated for no real gain. (Important here is that the child
1130 : : * members have not yet received any processing beyond being pulled
1131 : : * up.) Similarly, in appendrels created by inheritance expansion,
1132 : : * it's sufficient to look at the parent relation.
1133 : : */
1134 : :
1135 : : /* ignore RTEs that are "other rels" */
5025 1136 [ - + ]: 17344 : if (brel->reloptkind != RELOPT_BASEREL)
5025 tgl@sss.pgh.pa.us 1137 :UBC 0 : continue;
1138 : :
5025 tgl@sss.pgh.pa.us 1139 :CBC 17344 : extract_lateral_references(root, brel, rti);
1140 : : }
1141 : : }
1142 : :
1143 : : static void
1144 : 17344 : extract_lateral_references(PlannerInfo *root, RelOptInfo *brel, Index rtindex)
1145 : : {
5044 1146 : 17344 : RangeTblEntry *rte = root->simple_rte_array[rtindex];
1147 : : List *vars;
1148 : : List *newvars;
1149 : : Relids where_needed;
1150 : : ListCell *lc;
1151 : :
1152 : : /* No cross-references are possible if it's not LATERAL */
1153 [ + + ]: 17344 : if (!rte->lateral)
1154 : 11261 : return;
1155 : :
1156 : : /* Fetch the appropriate variables */
3962 1157 [ + + ]: 6083 : if (rte->rtekind == RTE_RELATION)
1158 : 31 : vars = pull_vars_of_level((Node *) rte->tablesample, 0);
1159 [ + + ]: 6052 : else if (rte->rtekind == RTE_SUBQUERY)
5044 1160 : 1269 : vars = pull_vars_of_level((Node *) rte->subquery, 1);
1161 [ + + ]: 4783 : else if (rte->rtekind == RTE_FUNCTION)
4573 1162 : 4528 : vars = pull_vars_of_level((Node *) rte->functions, 0);
3370 alvherre@alvh.no-ip. 1163 [ + + ]: 255 : else if (rte->rtekind == RTE_TABLEFUNC)
1164 : 195 : vars = pull_vars_of_level((Node *) rte->tablefunc, 0);
5039 tgl@sss.pgh.pa.us 1165 [ + - ]: 60 : else if (rte->rtekind == RTE_VALUES)
1166 : 60 : vars = pull_vars_of_level((Node *) rte->values_lists, 0);
1167 : : else
1168 : : {
5025 tgl@sss.pgh.pa.us 1169 :UBC 0 : Assert(false);
1170 : : return; /* keep compiler quiet */
1171 : : }
1172 : :
5025 tgl@sss.pgh.pa.us 1173 [ + + ]:CBC 6083 : if (vars == NIL)
1174 : 254 : return; /* nothing to do */
1175 : :
1176 : : /* Copy each Var (or PlaceHolderVar) and adjust it to match our level */
5044 1177 : 5829 : newvars = NIL;
1178 [ + - + + : 14247 : foreach(lc, vars)
+ + ]
1179 : : {
4749 bruce@momjian.us 1180 : 8418 : Node *node = (Node *) lfirst(lc);
1181 : :
5025 tgl@sss.pgh.pa.us 1182 : 8418 : node = copyObject(node);
1183 [ + + ]: 8418 : if (IsA(node, Var))
1184 : : {
4749 bruce@momjian.us 1185 : 8313 : Var *var = (Var *) node;
1186 : :
1187 : : /* Adjustment is easy since it's just one node */
5025 tgl@sss.pgh.pa.us 1188 : 8313 : var->varlevelsup = 0;
1189 : : }
1190 [ + - ]: 105 : else if (IsA(node, PlaceHolderVar))
1191 : : {
1192 : 105 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
4749 bruce@momjian.us 1193 : 105 : int levelsup = phv->phlevelsup;
1194 : :
1195 : : /* Have to work harder to adjust the contained expression too */
5025 tgl@sss.pgh.pa.us 1196 [ + + ]: 105 : if (levelsup != 0)
1197 : 75 : IncrementVarSublevelsUp(node, -levelsup, 0);
1198 : :
1199 : : /*
1200 : : * If we pulled the PHV out of a subquery RTE, its expression
1201 : : * needs to be preprocessed. subquery_planner() already did this
1202 : : * for level-zero PHVs in function and values RTEs, though.
1203 : : */
1204 [ + + ]: 105 : if (levelsup > 0)
1205 : 75 : phv->phexpr = preprocess_phv_expression(root, phv->phexpr);
1206 : : }
1207 : : else
5033 tgl@sss.pgh.pa.us 1208 :UBC 0 : Assert(false);
5025 tgl@sss.pgh.pa.us 1209 :CBC 8418 : newvars = lappend(newvars, node);
1210 : : }
1211 : :
1212 : 5829 : list_free(vars);
1213 : :
1214 : : /*
1215 : : * We mark the Vars as being "needed" at the LATERAL RTE. This is a bit
1216 : : * of a cheat: a more formal approach would be to mark each one as needed
1217 : : * at the join of the LATERAL RTE with its source RTE. But it will work,
1218 : : * and it's much less tedious than computing a separate where_needed for
1219 : : * each Var.
1220 : : */
5044 1221 : 5829 : where_needed = bms_make_singleton(rtindex);
1222 : :
1223 : : /*
1224 : : * Push Vars into their source relations' targetlists, and PHVs into
1225 : : * root->placeholder_list.
1226 : : */
1382 1227 : 5829 : add_vars_to_targetlist(root, newvars, where_needed);
1228 : :
1229 : : /*
1230 : : * Remember the lateral references for rebuild_lateral_attr_needed and
1231 : : * create_lateral_join_info.
1232 : : */
5025 1233 : 5829 : brel->lateral_vars = newvars;
1234 : : }
1235 : :
1236 : : /*
1237 : : * rebuild_lateral_attr_needed
1238 : : * Put back attr_needed bits for Vars/PHVs needed for lateral references.
1239 : : *
1240 : : * This is used to rebuild attr_needed/ph_needed sets after removal of a
1241 : : * useless outer join. It should match what find_lateral_references did,
1242 : : * except that we call add_vars_to_attr_needed not add_vars_to_targetlist.
1243 : : */
1244 : : void
610 1245 : 9177 : rebuild_lateral_attr_needed(PlannerInfo *root)
1246 : : {
1247 : : Index rti;
1248 : :
1249 : : /* We need do nothing if the query contains no LATERAL RTEs */
1250 [ + + ]: 9177 : if (!root->hasLateralRTEs)
1251 : 8268 : return;
1252 : :
1253 : : /* Examine the same baserels that find_lateral_references did */
1254 [ + + ]: 10236 : for (rti = 1; rti < root->simple_rel_array_size; rti++)
1255 : : {
1256 : 9327 : RelOptInfo *brel = root->simple_rel_array[rti];
1257 : : Relids where_needed;
1258 : :
1259 [ + + ]: 9327 : if (brel == NULL)
1260 : 5742 : continue;
1261 [ - + ]: 3585 : if (brel->reloptkind != RELOPT_BASEREL)
610 tgl@sss.pgh.pa.us 1262 :UBC 0 : continue;
1263 : :
1264 : : /*
1265 : : * We don't need to repeat all of extract_lateral_references, since it
1266 : : * kindly saved the extracted Vars/PHVs in lateral_vars.
1267 : : */
610 tgl@sss.pgh.pa.us 1268 [ + + ]:CBC 3585 : if (brel->lateral_vars == NIL)
1269 : 2902 : continue;
1270 : :
1271 : 683 : where_needed = bms_make_singleton(rti);
1272 : :
1273 : 683 : add_vars_to_attr_needed(root, brel->lateral_vars, where_needed);
1274 : : }
1275 : : }
1276 : :
1277 : : /*
1278 : : * create_lateral_join_info
1279 : : * Fill in the per-base-relation direct_lateral_relids, lateral_relids
1280 : : * and lateral_referencers sets.
1281 : : */
1282 : : void
5025 1283 : 255472 : create_lateral_join_info(PlannerInfo *root)
1284 : : {
3823 1285 : 255472 : bool found_laterals = false;
1286 : : Index rti;
1287 : : ListCell *lc;
1288 : :
1289 : : /* We need do nothing if the query contains no LATERAL RTEs */
5025 1290 [ + + ]: 255472 : if (!root->hasLateralRTEs)
1291 : 248559 : return;
1292 : :
1293 : : /* We'll need to have the ph_eval_at values for PlaceHolderVars */
1211 1294 [ - + ]: 6913 : Assert(root->placeholdersFrozen);
1295 : :
1296 : : /*
1297 : : * Examine all baserels (the rel array has been set up by now).
1298 : : */
5025 1299 [ + + ]: 32905 : for (rti = 1; rti < root->simple_rel_array_size; rti++)
1300 : : {
1301 : 25992 : RelOptInfo *brel = root->simple_rel_array[rti];
1302 : : Relids lateral_relids;
1303 : :
1304 : : /* there may be empty slots corresponding to non-baserel RTEs */
1305 [ + + ]: 25992 : if (brel == NULL)
1306 : 9557 : continue;
1307 : :
3265 1308 [ - + ]: 16435 : Assert(brel->relid == rti); /* sanity check on array */
1309 : :
1310 : : /* ignore RTEs that are "other rels" */
5025 1311 [ - + ]: 16435 : if (brel->reloptkind != RELOPT_BASEREL)
5025 tgl@sss.pgh.pa.us 1312 :UBC 0 : continue;
1313 : :
5025 tgl@sss.pgh.pa.us 1314 :CBC 16435 : lateral_relids = NULL;
1315 : :
1316 : : /* consider each laterally-referenced Var or PHV */
1317 [ + + + + : 24700 : foreach(lc, brel->lateral_vars)
+ + ]
1318 : : {
4749 bruce@momjian.us 1319 : 8265 : Node *node = (Node *) lfirst(lc);
1320 : :
5025 tgl@sss.pgh.pa.us 1321 [ + + ]: 8265 : if (IsA(node, Var))
1322 : : {
4749 bruce@momjian.us 1323 : 8160 : Var *var = (Var *) node;
1324 : :
3823 tgl@sss.pgh.pa.us 1325 : 8160 : found_laterals = true;
5025 1326 : 8160 : lateral_relids = bms_add_member(lateral_relids,
1327 : : var->varno);
1328 : : }
1329 [ + - ]: 105 : else if (IsA(node, PlaceHolderVar))
1330 : : {
1331 : 105 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1382 1332 : 105 : PlaceHolderInfo *phinfo = find_placeholder_info(root, phv);
1333 : :
3823 1334 : 105 : found_laterals = true;
5025 1335 : 105 : lateral_relids = bms_add_members(lateral_relids,
1336 : 105 : phinfo->ph_eval_at);
1337 : : }
1338 : : else
5025 tgl@sss.pgh.pa.us 1339 :UBC 0 : Assert(false);
1340 : : }
1341 : :
1342 : : /* We now have all the simple lateral refs from this rel */
3823 tgl@sss.pgh.pa.us 1343 :CBC 16435 : brel->direct_lateral_relids = lateral_relids;
1344 : 16435 : brel->lateral_relids = bms_copy(lateral_relids);
1345 : : }
1346 : :
1347 : : /*
1348 : : * Now check for lateral references within PlaceHolderVars, and mark their
1349 : : * eval_at rels as having lateral references to the source rels.
1350 : : *
1351 : : * For a PHV that is due to be evaluated at a baserel, mark its source(s)
1352 : : * as direct lateral dependencies of the baserel (adding onto the ones
1353 : : * recorded above). If it's due to be evaluated at a join, mark its
1354 : : * source(s) as indirect lateral dependencies of each baserel in the join,
1355 : : * ie put them into lateral_relids but not direct_lateral_relids. This is
1356 : : * appropriate because we can't put any such baserel on the outside of a
1357 : : * join to one of the PHV's lateral dependencies, but on the other hand we
1358 : : * also can't yet join it directly to the dependency.
1359 : : */
4669 1360 [ + + + + : 7366 : foreach(lc, root->placeholder_list)
+ + ]
1361 : : {
1362 : 453 : PlaceHolderInfo *phinfo = (PlaceHolderInfo *) lfirst(lc);
1363 : 453 : Relids eval_at = phinfo->ph_eval_at;
1364 : : Relids lateral_refs;
1365 : : int varno;
1366 : :
3823 1367 [ + + ]: 453 : if (phinfo->ph_lateral == NULL)
1368 : 236 : continue; /* PHV is uninteresting if no lateral refs */
1369 : :
1370 : 217 : found_laterals = true;
1371 : :
1372 : : /*
1373 : : * Include only baserels not outer joins in the evaluation sites'
1374 : : * lateral relids. This avoids problems when outer join order gets
1375 : : * rearranged, and it should still ensure that the lateral values are
1376 : : * available when needed.
1377 : : */
1075 1378 : 217 : lateral_refs = bms_intersect(phinfo->ph_lateral, root->all_baserels);
1379 [ - + ]: 217 : Assert(!bms_is_empty(lateral_refs));
1380 : :
3823 1381 [ + + ]: 217 : if (bms_get_singleton_member(eval_at, &varno))
1382 : : {
1383 : : /* Evaluation site is a baserel */
1384 : 162 : RelOptInfo *brel = find_base_rel(root, varno);
1385 : :
1386 : 162 : brel->direct_lateral_relids =
1387 : 162 : bms_add_members(brel->direct_lateral_relids,
1388 : : lateral_refs);
1389 : 162 : brel->lateral_relids =
1390 : 162 : bms_add_members(brel->lateral_relids,
1391 : : lateral_refs);
1392 : : }
1393 : : else
1394 : : {
1395 : : /* Evaluation site is a join */
1396 : 55 : varno = -1;
1397 [ + + ]: 165 : while ((varno = bms_next_member(eval_at, varno)) >= 0)
1398 : : {
1216 1399 : 110 : RelOptInfo *brel = find_base_rel_ignore_join(root, varno);
1400 : :
1401 [ - + ]: 110 : if (brel == NULL)
1216 tgl@sss.pgh.pa.us 1402 :UBC 0 : continue; /* ignore outer joins in eval_at */
3823 tgl@sss.pgh.pa.us 1403 :CBC 110 : brel->lateral_relids = bms_add_members(brel->lateral_relids,
1404 : : lateral_refs);
1405 : : }
1406 : : }
1407 : : }
1408 : :
1409 : : /*
1410 : : * If we found no actual lateral references, we're done; but reset the
1411 : : * hasLateralRTEs flag to avoid useless work later.
1412 : : */
1413 [ + + ]: 6913 : if (!found_laterals)
1414 : : {
1415 : 1091 : root->hasLateralRTEs = false;
4669 1416 : 1091 : return;
1417 : : }
1418 : :
1419 : : /*
1420 : : * Calculate the transitive closure of the lateral_relids sets, so that
1421 : : * they describe both direct and indirect lateral references. If relation
1422 : : * X references Y laterally, and Y references Z laterally, then we will
1423 : : * have to scan X on the inside of a nestloop with Z, so for all intents
1424 : : * and purposes X is laterally dependent on Z too.
1425 : : *
1426 : : * This code is essentially Warshall's algorithm for transitive closure.
1427 : : * The outer loop considers each baserel, and propagates its lateral
1428 : : * dependencies to those baserels that have a lateral dependency on it.
1429 : : */
1430 [ + + ]: 25900 : for (rti = 1; rti < root->simple_rel_array_size; rti++)
1431 : : {
1432 : 20078 : RelOptInfo *brel = root->simple_rel_array[rti];
1433 : : Relids outer_lateral_relids;
1434 : : Index rti2;
1435 : :
3823 1436 [ + + - + ]: 20078 : if (brel == NULL || brel->reloptkind != RELOPT_BASEREL)
4669 1437 : 5968 : continue;
1438 : :
1439 : : /* need not consider baserel further if it has no lateral refs */
3823 1440 : 14110 : outer_lateral_relids = brel->lateral_relids;
1441 [ + + ]: 14110 : if (outer_lateral_relids == NULL)
4669 1442 : 8162 : continue;
1443 : :
1444 : : /* else scan all baserels */
3823 1445 [ + + ]: 26834 : for (rti2 = 1; rti2 < root->simple_rel_array_size; rti2++)
1446 : : {
1447 : 20886 : RelOptInfo *brel2 = root->simple_rel_array[rti2];
1448 : :
1449 [ + + - + ]: 20886 : if (brel2 == NULL || brel2->reloptkind != RELOPT_BASEREL)
1450 : 6313 : continue;
1451 : :
1452 : : /* if brel2 has lateral ref to brel, propagate brel's refs */
1453 [ + + ]: 14573 : if (bms_is_member(rti, brel2->lateral_relids))
1454 : 56 : brel2->lateral_relids = bms_add_members(brel2->lateral_relids,
1455 : : outer_lateral_relids);
1456 : : }
1457 : : }
1458 : :
1459 : : /*
1460 : : * Now that we've identified all lateral references, mark each baserel
1461 : : * with the set of relids of rels that reference it laterally (possibly
1462 : : * indirectly) --- that is, the inverse mapping of lateral_relids.
1463 : : */
1464 [ + + ]: 25900 : for (rti = 1; rti < root->simple_rel_array_size; rti++)
1465 : : {
1466 : 20078 : RelOptInfo *brel = root->simple_rel_array[rti];
1467 : : Relids lateral_relids;
1468 : : int rti2;
1469 : :
1470 [ + + - + ]: 20078 : if (brel == NULL || brel->reloptkind != RELOPT_BASEREL)
1471 : 5968 : continue;
1472 : :
1473 : : /* Nothing to do at rels with no lateral refs */
1474 : 14110 : lateral_relids = brel->lateral_relids;
1185 1475 [ + + ]: 14110 : if (bms_is_empty(lateral_relids))
3823 1476 : 8162 : continue;
1477 : :
1478 : : /* No rel should have a lateral dependency on itself */
1479 [ - + ]: 5948 : Assert(!bms_is_member(rti, lateral_relids));
1480 : :
1481 : : /* Mark this rel's referencees */
1482 : 5948 : rti2 = -1;
1483 [ + + ]: 12352 : while ((rti2 = bms_next_member(lateral_relids, rti2)) >= 0)
1484 : : {
1485 : 6404 : RelOptInfo *brel2 = root->simple_rel_array[rti2];
1486 : :
1216 1487 [ + + ]: 6404 : if (brel2 == NULL)
1488 : 10 : continue; /* must be an OJ */
1489 : :
1490 [ - + ]: 6394 : Assert(brel2->reloptkind == RELOPT_BASEREL);
3823 1491 : 6394 : brel2->lateral_referencers =
1492 : 6394 : bms_add_member(brel2->lateral_referencers, rti);
1493 : : }
1494 : : }
1495 : : }
1496 : :
1497 : :
1498 : : /*****************************************************************************
1499 : : *
1500 : : * JOIN TREE PROCESSING
1501 : : *
1502 : : *****************************************************************************/
1503 : :
1504 : : /*
1505 : : * deconstruct_jointree
1506 : : * Recursively scan the query's join tree for WHERE and JOIN/ON qual
1507 : : * clauses, and add these to the appropriate restrictinfo and joininfo
1508 : : * lists belonging to base RelOptInfos. Also, add SpecialJoinInfo nodes
1509 : : * to root->join_info_list for any outer joins appearing in the query tree.
1510 : : * Return a "joinlist" data structure showing the join order decisions
1511 : : * that need to be made by make_one_rel().
1512 : : *
1513 : : * The "joinlist" result is a list of items that are either RangeTblRef
1514 : : * jointree nodes or sub-joinlists. All the items at the same level of
1515 : : * joinlist must be joined in an order to be determined by make_one_rel()
1516 : : * (note that legal orders may be constrained by SpecialJoinInfo nodes).
1517 : : * A sub-joinlist represents a subproblem to be planned separately. Currently
1518 : : * sub-joinlists arise only from FULL OUTER JOIN or when collapsing of
1519 : : * subproblems is stopped by join_collapse_limit or from_collapse_limit.
1520 : : */
1521 : : List *
7466 1522 : 255472 : deconstruct_jointree(PlannerInfo *root)
1523 : : {
1524 : : List *result;
1525 : : JoinDomain *top_jdomain;
1216 1526 : 255472 : List *item_list = NIL;
1527 : : ListCell *lc;
1528 : :
1529 : : /*
1530 : : * After this point, no more PlaceHolderInfos may be made, because
1531 : : * make_outerjoininfo requires all active placeholders to be present in
1532 : : * root->placeholder_list while we crawl up the join tree.
1533 : : */
1382 1534 : 255472 : root->placeholdersFrozen = true;
1535 : :
1536 : : /* Fetch the already-created top-level join domain for the query */
1216 1537 : 255472 : top_jdomain = linitial_node(JoinDomain, root->join_domains);
1538 : 255472 : top_jdomain->jd_relids = NULL; /* filled during deconstruct_recurse */
1539 : :
1540 : : /* Start recursion at top of jointree */
7466 1541 [ + - - + ]: 255472 : Assert(root->parse->jointree != NULL &&
1542 : : IsA(root->parse->jointree, FromExpr));
1543 : :
1544 : : /* These are filled as we scan the jointree */
1216 1545 : 255472 : root->all_baserels = NULL;
1546 : 255472 : root->outer_join_rels = NULL;
1547 : :
1548 : : /* Perform the initial scan of the jointree */
1549 : 255472 : result = deconstruct_recurse(root, (Node *) root->parse->jointree,
1550 : : top_jdomain, NULL,
1551 : : &item_list);
1552 : :
1553 : : /* Now we can form the value of all_query_rels, too */
1554 : 255472 : root->all_query_rels = bms_union(root->all_baserels, root->outer_join_rels);
1555 : :
1556 : : /* ... which should match what we computed for the top join domain */
1557 [ - + ]: 255472 : Assert(bms_equal(root->all_query_rels, top_jdomain->jd_relids));
1558 : :
1559 : : /* Now scan all the jointree nodes again, and distribute quals */
1560 [ + - + + : 982790 : foreach(lc, item_list)
+ + ]
1561 : : {
1562 : 727318 : JoinTreeItem *jtitem = (JoinTreeItem *) lfirst(lc);
1563 : :
1211 1564 : 727318 : deconstruct_distribute(root, jtitem);
1565 : : }
1566 : :
1567 : : /*
1568 : : * If there were any special joins then we may have some postponed LEFT
1569 : : * JOIN clauses to deal with.
1570 : : */
1216 1571 [ + + ]: 255472 : if (root->join_info_list)
1572 : : {
1573 [ + - + + : 215346 : foreach(lc, item_list)
+ + ]
1574 : : {
1575 : 182301 : JoinTreeItem *jtitem = (JoinTreeItem *) lfirst(lc);
1576 : :
1577 [ + + ]: 182301 : if (jtitem->oj_joinclauses != NIL)
1578 : 31841 : deconstruct_distribute_oj_quals(root, item_list, jtitem);
1579 : : }
1580 : : }
1581 : :
1582 : : /* Don't need the JoinTreeItems any more */
1583 : 255472 : list_free_deep(item_list);
1584 : :
4667 1585 : 255472 : return result;
1586 : : }
1587 : :
1588 : : /*
1589 : : * deconstruct_recurse
1590 : : * One recursion level of deconstruct_jointree's initial jointree scan.
1591 : : *
1592 : : * jtnode is the jointree node to examine, and parent_domain is the
1593 : : * enclosing join domain. (We must add all base+OJ relids appearing
1594 : : * here or below to parent_domain.) parent_jtitem is the JoinTreeItem
1595 : : * for the parent jointree node, or NULL at the top of the recursion.
1596 : : *
1597 : : * item_list is an in/out parameter: we add a JoinTreeItem struct to
1598 : : * that list for each jointree node, in depth-first traversal order.
1599 : : * (Hence, after each call, the last list item corresponds to its jtnode.)
1600 : : *
1601 : : * Return value is the appropriate joinlist for this jointree node.
1602 : : */
1603 : : static List *
1216 1604 : 727318 : deconstruct_recurse(PlannerInfo *root, Node *jtnode,
1605 : : JoinDomain *parent_domain,
1606 : : JoinTreeItem *parent_jtitem,
1607 : : List **item_list)
1608 : : {
1609 : : List *joinlist;
1610 : : JoinTreeItem *jtitem;
1611 : :
1612 [ - + ]: 727318 : Assert(jtnode != NULL);
1613 : :
1614 : : /* Make the new JoinTreeItem, but don't add it to item_list yet */
1615 : 727318 : jtitem = palloc0_object(JoinTreeItem);
1616 : 727318 : jtitem->jtnode = jtnode;
1211 1617 : 727318 : jtitem->jti_parent = parent_jtitem;
1618 : :
9374 1619 [ + + ]: 727318 : if (IsA(jtnode, RangeTblRef))
1620 : : {
1621 : 376047 : int varno = ((RangeTblRef *) jtnode)->rtindex;
1622 : :
1623 : : /* Fill all_baserels as we encounter baserel jointree nodes */
1216 1624 : 376047 : root->all_baserels = bms_add_member(root->all_baserels, varno);
1625 : : /* This node belongs to parent_domain */
1626 : 376047 : jtitem->jdomain = parent_domain;
1627 : 376047 : parent_domain->jd_relids = bms_add_member(parent_domain->jd_relids,
1628 : : varno);
1629 : : /* qualscope is just the one RTE */
1630 : 376047 : jtitem->qualscope = bms_make_singleton(varno);
1631 : : /* A single baserel does not create an inner join */
1632 : 376047 : jtitem->inner_join_rels = NULL;
7466 1633 : 376047 : joinlist = list_make1(jtnode);
1634 : : }
9374 1635 [ + + ]: 351271 : else if (IsA(jtnode, FromExpr))
1636 : : {
1637 : 268380 : FromExpr *f = (FromExpr *) jtnode;
1638 : : int remaining;
1639 : : ListCell *l;
1640 : :
1641 : : /* This node belongs to parent_domain, as do its children */
1216 1642 : 268380 : jtitem->jdomain = parent_domain;
1643 : :
1644 : : /*
1645 : : * Recurse to handle child nodes, and compute output joinlist. We
1646 : : * collapse subproblems into a single joinlist whenever the resulting
1647 : : * joinlist wouldn't exceed from_collapse_limit members. Also, always
1648 : : * collapse one-element subproblems, since that won't lengthen the
1649 : : * joinlist anyway.
1650 : : */
1651 : 268380 : jtitem->qualscope = NULL;
1652 : 268380 : jtitem->inner_join_rels = NULL;
7466 1653 : 268380 : joinlist = NIL;
1654 : 268380 : remaining = list_length(f->fromlist);
9374 1655 [ + - + + : 574444 : foreach(l, f->fromlist)
+ + ]
1656 : : {
1657 : : JoinTreeItem *sub_item;
1658 : : List *sub_joinlist;
1659 : : int sub_members;
1660 : :
7466 1661 : 306064 : sub_joinlist = deconstruct_recurse(root, lfirst(l),
1662 : : parent_domain,
1663 : : jtitem,
1664 : : item_list);
1216 1665 : 306064 : sub_item = (JoinTreeItem *) llast(*item_list);
1666 : 612128 : jtitem->qualscope = bms_add_members(jtitem->qualscope,
1667 : 306064 : sub_item->qualscope);
1668 : 306064 : jtitem->inner_join_rels = sub_item->inner_join_rels;
7466 1669 : 306064 : sub_members = list_length(sub_joinlist);
1670 : 306064 : remaining--;
1671 [ + + ]: 306064 : if (sub_members <= 1 ||
1672 [ + + ]: 55857 : list_length(joinlist) + sub_members + remaining <= from_collapse_limit)
1673 : 306054 : joinlist = list_concat(joinlist, sub_joinlist);
1674 : : else
1675 : 10 : joinlist = lappend(joinlist, sub_joinlist);
1676 : : }
1677 : :
1678 : : /*
1679 : : * A FROM with more than one list element is an inner join subsuming
1680 : : * all below it, so we should report inner_join_rels = qualscope. If
1681 : : * there was exactly one element, we should (and already did) report
1682 : : * whatever its inner_join_rels were. If there were no elements (is
1683 : : * that still possible?) the initialization before the loop fixed it.
1684 : : */
6847 1685 [ + + ]: 268380 : if (list_length(f->fromlist) > 1)
1216 1686 : 32721 : jtitem->inner_join_rels = jtitem->qualscope;
1687 : : }
9391 1688 [ + - ]: 82891 : else if (IsA(jtnode, JoinExpr))
1689 : : {
1690 : 82891 : JoinExpr *j = (JoinExpr *) jtnode;
1691 : : JoinDomain *child_domain,
1692 : : *fj_domain;
1693 : : JoinTreeItem *left_item,
1694 : : *right_item;
1695 : : List *leftjoinlist,
1696 : : *rightjoinlist;
1697 : :
1698 [ + + + + : 82891 : switch (j->jointype)
- ]
1699 : : {
1700 : 39066 : case JOIN_INNER:
1701 : : /* This node belongs to parent_domain, as do its children */
1216 1702 : 39066 : jtitem->jdomain = parent_domain;
1703 : : /* Recurse */
7466 1704 : 39066 : leftjoinlist = deconstruct_recurse(root, j->larg,
1705 : : parent_domain,
1706 : : jtitem,
1707 : : item_list);
1216 1708 : 39066 : left_item = (JoinTreeItem *) llast(*item_list);
7466 1709 : 39066 : rightjoinlist = deconstruct_recurse(root, j->rarg,
1710 : : parent_domain,
1711 : : jtitem,
1712 : : item_list);
1216 1713 : 39066 : right_item = (JoinTreeItem *) llast(*item_list);
1714 : : /* Compute qualscope etc */
1715 : 78132 : jtitem->qualscope = bms_union(left_item->qualscope,
1716 : 39066 : right_item->qualscope);
1717 : 39066 : jtitem->inner_join_rels = jtitem->qualscope;
1718 : 39066 : jtitem->left_rels = left_item->qualscope;
1719 : 39066 : jtitem->right_rels = right_item->qualscope;
1720 : : /* Inner join adds no restrictions for quals */
1721 : 39066 : jtitem->nonnullable_rels = NULL;
9391 1722 : 39066 : break;
1723 : 38984 : case JOIN_LEFT:
1724 : : case JOIN_ANTI:
1725 : : /* Make new join domain for my quals and the RHS */
1216 1726 : 38984 : child_domain = makeNode(JoinDomain);
1727 : 38984 : child_domain->jd_relids = NULL; /* filled by recursion */
1728 : 38984 : root->join_domains = lappend(root->join_domains, child_domain);
1729 : 38984 : jtitem->jdomain = child_domain;
1730 : : /* Recurse */
7466 1731 : 38984 : leftjoinlist = deconstruct_recurse(root, j->larg,
1732 : : parent_domain,
1733 : : jtitem,
1734 : : item_list);
1216 1735 : 38984 : left_item = (JoinTreeItem *) llast(*item_list);
7466 1736 : 38984 : rightjoinlist = deconstruct_recurse(root, j->rarg,
1737 : : child_domain,
1738 : : jtitem,
1739 : : item_list);
1216 1740 : 38984 : right_item = (JoinTreeItem *) llast(*item_list);
1741 : : /* Compute join domain contents, qualscope etc */
1742 : 38984 : parent_domain->jd_relids =
1743 : 38984 : bms_add_members(parent_domain->jd_relids,
1744 : 38984 : child_domain->jd_relids);
1745 : 77968 : jtitem->qualscope = bms_union(left_item->qualscope,
1746 : 38984 : right_item->qualscope);
1747 : : /* caution: ANTI join derived from SEMI will lack rtindex */
1748 [ + + ]: 38984 : if (j->rtindex != 0)
1749 : : {
1750 : 34116 : parent_domain->jd_relids =
1751 : 34116 : bms_add_member(parent_domain->jd_relids,
1752 : : j->rtindex);
1753 : 34116 : jtitem->qualscope = bms_add_member(jtitem->qualscope,
1754 : : j->rtindex);
1755 : 34116 : root->outer_join_rels = bms_add_member(root->outer_join_rels,
1756 : : j->rtindex);
1757 : 34116 : mark_rels_nulled_by_join(root, j->rtindex,
1758 : : right_item->qualscope);
1759 : : }
1760 : 77968 : jtitem->inner_join_rels = bms_union(left_item->inner_join_rels,
1761 : 38984 : right_item->inner_join_rels);
1762 : 38984 : jtitem->left_rels = left_item->qualscope;
1763 : 38984 : jtitem->right_rels = right_item->qualscope;
1764 : 38984 : jtitem->nonnullable_rels = left_item->qualscope;
9391 1765 : 38984 : break;
6303 1766 : 4020 : case JOIN_SEMI:
1767 : : /* This node belongs to parent_domain, as do its children */
1216 1768 : 4020 : jtitem->jdomain = parent_domain;
1769 : : /* Recurse */
6303 1770 : 4020 : leftjoinlist = deconstruct_recurse(root, j->larg,
1771 : : parent_domain,
1772 : : jtitem,
1773 : : item_list);
1216 1774 : 4020 : left_item = (JoinTreeItem *) llast(*item_list);
6303 1775 : 4020 : rightjoinlist = deconstruct_recurse(root, j->rarg,
1776 : : parent_domain,
1777 : : jtitem,
1778 : : item_list);
1216 1779 : 4020 : right_item = (JoinTreeItem *) llast(*item_list);
1780 : : /* Compute qualscope etc */
1781 : 8040 : jtitem->qualscope = bms_union(left_item->qualscope,
1782 : 4020 : right_item->qualscope);
1783 : : /* SEMI join never has rtindex, so don't add to anything */
1784 [ - + ]: 4020 : Assert(j->rtindex == 0);
1785 : 8040 : jtitem->inner_join_rels = bms_union(left_item->inner_join_rels,
1786 : 4020 : right_item->inner_join_rels);
1787 : 4020 : jtitem->left_rels = left_item->qualscope;
1788 : 4020 : jtitem->right_rels = right_item->qualscope;
1789 : : /* Semi join adds no restrictions for quals */
1790 : 4020 : jtitem->nonnullable_rels = NULL;
6303 1791 : 4020 : break;
9391 1792 : 821 : case JOIN_FULL:
1793 : : /* The FULL JOIN's quals need their very own domain */
1216 1794 : 821 : fj_domain = makeNode(JoinDomain);
1795 : 821 : root->join_domains = lappend(root->join_domains, fj_domain);
1796 : 821 : jtitem->jdomain = fj_domain;
1797 : : /* Recurse, giving each side its own join domain */
1798 : 821 : child_domain = makeNode(JoinDomain);
1799 : 821 : child_domain->jd_relids = NULL; /* filled by recursion */
1800 : 821 : root->join_domains = lappend(root->join_domains, child_domain);
7466 1801 : 821 : leftjoinlist = deconstruct_recurse(root, j->larg,
1802 : : child_domain,
1803 : : jtitem,
1804 : : item_list);
1216 1805 : 821 : left_item = (JoinTreeItem *) llast(*item_list);
1806 : 821 : fj_domain->jd_relids = bms_copy(child_domain->jd_relids);
1807 : 821 : child_domain = makeNode(JoinDomain);
1808 : 821 : child_domain->jd_relids = NULL; /* filled by recursion */
1809 : 821 : root->join_domains = lappend(root->join_domains, child_domain);
7466 1810 : 821 : rightjoinlist = deconstruct_recurse(root, j->rarg,
1811 : : child_domain,
1812 : : jtitem,
1813 : : item_list);
1216 1814 : 821 : right_item = (JoinTreeItem *) llast(*item_list);
1815 : : /* Compute qualscope etc */
1816 : 1642 : fj_domain->jd_relids = bms_add_members(fj_domain->jd_relids,
1817 : 821 : child_domain->jd_relids);
1818 : 1642 : parent_domain->jd_relids = bms_add_members(parent_domain->jd_relids,
1819 : 821 : fj_domain->jd_relids);
1820 : 1642 : jtitem->qualscope = bms_union(left_item->qualscope,
1821 : 821 : right_item->qualscope);
1822 [ - + ]: 821 : Assert(j->rtindex != 0);
1823 : 821 : parent_domain->jd_relids = bms_add_member(parent_domain->jd_relids,
1824 : : j->rtindex);
1825 : 821 : jtitem->qualscope = bms_add_member(jtitem->qualscope,
1826 : : j->rtindex);
1827 : 821 : root->outer_join_rels = bms_add_member(root->outer_join_rels,
1828 : : j->rtindex);
1829 : 821 : mark_rels_nulled_by_join(root, j->rtindex,
1830 : : left_item->qualscope);
1831 : 821 : mark_rels_nulled_by_join(root, j->rtindex,
1832 : : right_item->qualscope);
1833 : 1642 : jtitem->inner_join_rels = bms_union(left_item->inner_join_rels,
1834 : 821 : right_item->inner_join_rels);
1835 : 821 : jtitem->left_rels = left_item->qualscope;
1836 : 821 : jtitem->right_rels = right_item->qualscope;
1837 : : /* each side is both outer and inner */
1838 : 821 : jtitem->nonnullable_rels = jtitem->qualscope;
9391 1839 : 821 : break;
9391 tgl@sss.pgh.pa.us 1840 :UBC 0 : default:
1841 : : /* JOIN_RIGHT was eliminated during reduce_outer_joins() */
8345 1842 [ # # ]: 0 : elog(ERROR, "unrecognized join type: %d",
1843 : : (int) j->jointype);
1844 : : leftjoinlist = rightjoinlist = NIL; /* keep compiler quiet */
1845 : : break;
1846 : : }
1847 : :
1848 : : /*
1849 : : * Compute the output joinlist. We fold subproblems together except
1850 : : * at a FULL JOIN or where join_collapse_limit would be exceeded.
1851 : : */
1216 tgl@sss.pgh.pa.us 1852 [ + + ]:CBC 82891 : if (j->jointype == JOIN_FULL)
1853 : : {
1854 : : /* force the join order exactly at this node */
1855 : 821 : joinlist = list_make1(list_make2(leftjoinlist, rightjoinlist));
1856 : : }
1857 [ + + ]: 82070 : else if (list_length(leftjoinlist) + list_length(rightjoinlist) <=
1858 : : join_collapse_limit)
1859 : : {
1860 : : /* OK to combine subproblems */
1861 : 81925 : joinlist = list_concat(leftjoinlist, rightjoinlist);
1862 : : }
1863 : : else
1864 : : {
1865 : : /* can't combine, but needn't force join order above here */
1866 : : Node *leftpart,
1867 : : *rightpart;
1868 : :
1869 : : /* avoid creating useless 1-element sublists */
1870 [ + + ]: 145 : if (list_length(leftjoinlist) == 1)
1871 : 25 : leftpart = (Node *) linitial(leftjoinlist);
1872 : : else
1873 : 120 : leftpart = (Node *) leftjoinlist;
1874 [ + + ]: 145 : if (list_length(rightjoinlist) == 1)
1875 : 20 : rightpart = (Node *) linitial(rightjoinlist);
1876 : : else
1877 : 125 : rightpart = (Node *) rightjoinlist;
1878 : 145 : joinlist = list_make2(leftpart, rightpart);
1879 : : }
1880 : : }
1881 : : else
1882 : : {
1216 tgl@sss.pgh.pa.us 1883 [ # # ]:UBC 0 : elog(ERROR, "unrecognized node type: %d",
1884 : : (int) nodeTag(jtnode));
1885 : : joinlist = NIL; /* keep compiler quiet */
1886 : : }
1887 : :
1888 : : /* Finally, we can add the new JoinTreeItem to item_list */
1216 tgl@sss.pgh.pa.us 1889 :CBC 727318 : *item_list = lappend(*item_list, jtitem);
1890 : :
1891 : 727318 : return joinlist;
1892 : : }
1893 : :
1894 : : /*
1895 : : * deconstruct_distribute
1896 : : * Process one jointree node in phase 2 of deconstruct_jointree processing.
1897 : : *
1898 : : * Distribute quals of the node to appropriate restriction and join lists.
1899 : : * In addition, entries will be added to root->join_info_list for outer joins.
1900 : : */
1901 : : static void
1211 1902 : 727318 : deconstruct_distribute(PlannerInfo *root, JoinTreeItem *jtitem)
1903 : : {
1216 1904 : 727318 : Node *jtnode = jtitem->jtnode;
1905 : :
1906 [ + + ]: 727318 : if (IsA(jtnode, RangeTblRef))
1907 : : {
1908 : 376047 : int varno = ((RangeTblRef *) jtnode)->rtindex;
1909 : :
1910 : : /* Deal with any securityQuals attached to the RTE */
1911 [ + + ]: 376047 : if (root->qual_security_level > 0)
1912 : 2747 : process_security_barrier_quals(root,
1913 : : varno,
1914 : : jtitem);
1915 : : }
1916 [ + + ]: 351271 : else if (IsA(jtnode, FromExpr))
1917 : : {
1918 : 268380 : FromExpr *f = (FromExpr *) jtnode;
1919 : :
1920 : : /*
1921 : : * Process any lateral-referencing quals that were postponed to this
1922 : : * level by children.
1923 : : */
1211 1924 : 268380 : distribute_quals_to_rels(root, jtitem->lateral_clauses,
1925 : : jtitem,
1926 : : NULL,
1927 : : root->qual_security_level,
1928 : : jtitem->qualscope,
1929 : : NULL, NULL, NULL,
1930 : : true, false, false,
1931 : : NULL);
1932 : :
1933 : : /*
1934 : : * Now process the top-level quals.
1935 : : */
1216 1936 : 268380 : distribute_quals_to_rels(root, (List *) f->quals,
1937 : : jtitem,
1938 : : NULL,
1939 : : root->qual_security_level,
1940 : : jtitem->qualscope,
1941 : : NULL, NULL, NULL,
1942 : : true, false, false,
1943 : : NULL);
1944 : : }
1945 [ + - ]: 82891 : else if (IsA(jtnode, JoinExpr))
1946 : : {
1947 : 82891 : JoinExpr *j = (JoinExpr *) jtnode;
1948 : : Relids ojscope;
1949 : : List *my_quals;
1950 : : SpecialJoinInfo *sjinfo;
1951 : : List **postponed_oj_qual_list;
1952 : :
1953 : : /*
1954 : : * Include lateral-referencing quals postponed from children in
1955 : : * my_quals, so that they'll be handled properly in
1956 : : * make_outerjoininfo. (This is destructive to
1957 : : * jtitem->lateral_clauses, but we won't use that again.)
1958 : : */
1211 1959 : 82891 : my_quals = list_concat(jtitem->lateral_clauses,
1960 : 82891 : (List *) j->quals);
1961 : :
1962 : : /*
1963 : : * For an OJ, form the SpecialJoinInfo now, so that we can pass it to
1964 : : * distribute_qual_to_rels. We must compute its ojscope too.
1965 : : *
1966 : : * Semijoins are a bit of a hybrid: we build a SpecialJoinInfo, but we
1967 : : * want ojscope = NULL for distribute_qual_to_rels.
1968 : : */
7466 1969 [ + + ]: 82891 : if (j->jointype != JOIN_INNER)
1970 : : {
6498 1971 : 43825 : sjinfo = make_outerjoininfo(root,
1972 : : jtitem->left_rels,
1973 : : jtitem->right_rels,
1974 : : jtitem->inner_join_rels,
1975 : : j->jointype,
1216 1976 : 43825 : j->rtindex,
1977 : : my_quals);
1978 : 43825 : jtitem->sjinfo = sjinfo;
6303 1979 [ + + ]: 43825 : if (j->jointype == JOIN_SEMI)
1980 : 4020 : ojscope = NULL;
1981 : : else
1982 : 39805 : ojscope = bms_union(sjinfo->min_lefthand,
1983 : 39805 : sjinfo->min_righthand);
1984 : : }
1985 : : else
1986 : : {
6498 1987 : 39066 : sjinfo = NULL;
7466 1988 : 39066 : ojscope = NULL;
1989 : : }
1990 : :
1991 : : /*
1992 : : * If it's a left join with a join clause that is strict for the LHS,
1993 : : * then we need to postpone handling of any non-degenerate join
1994 : : * clauses, in case the join is able to commute with another left join
1995 : : * per identity 3. (Degenerate clauses need not be postponed, since
1996 : : * they will drop down below this join anyway.)
1997 : : */
1216 1998 [ + + + + ]: 82891 : if (j->jointype == JOIN_LEFT && sjinfo->lhs_strict)
1999 : : {
2000 : 31841 : postponed_oj_qual_list = &jtitem->oj_joinclauses;
2001 : :
2002 : : /*
2003 : : * Add back any commutable lower OJ relids that were removed from
2004 : : * min_lefthand or min_righthand, else the ojscope cross-check in
2005 : : * distribute_qual_to_rels will complain. Since we are postponing
2006 : : * processing of non-degenerate clauses, this addition doesn't
2007 : : * affect anything except that cross-check. Real clause
2008 : : * positioning decisions will be made later, when we revisit the
2009 : : * postponed clauses.
2010 : : */
1109 2011 : 31841 : ojscope = bms_add_members(ojscope, sjinfo->commute_below_l);
2012 : 31841 : ojscope = bms_add_members(ojscope, sjinfo->commute_below_r);
2013 : : }
2014 : : else
1216 2015 : 51050 : postponed_oj_qual_list = NULL;
2016 : :
2017 : : /* Process the JOIN's qual clauses */
2018 : 82891 : distribute_quals_to_rels(root, my_quals,
2019 : : jtitem,
2020 : : sjinfo,
2021 : : root->qual_security_level,
2022 : : jtitem->qualscope,
2023 : : ojscope, jtitem->nonnullable_rels,
2024 : : NULL, /* incompatible_relids */
2025 : : true, /* allow_equivalence */
2026 : : false, false, /* not clones */
2027 : : postponed_oj_qual_list);
2028 : :
2029 : : /* And add the SpecialJoinInfo to join_info_list */
6498 2030 [ + + ]: 82891 : if (sjinfo)
2031 : 43825 : root->join_info_list = lappend(root->join_info_list, sjinfo);
2032 : : }
2033 : : else
2034 : : {
8345 tgl@sss.pgh.pa.us 2035 [ # # ]:UBC 0 : elog(ERROR, "unrecognized node type: %d",
2036 : : (int) nodeTag(jtnode));
2037 : : }
9391 tgl@sss.pgh.pa.us 2038 :CBC 727318 : }
2039 : :
2040 : : /*
2041 : : * process_security_barrier_quals
2042 : : * Transfer security-barrier quals into relation's baserestrictinfo list.
2043 : : *
2044 : : * The rewriter put any relevant security-barrier conditions into the RTE's
2045 : : * securityQuals field, but it's now time to copy them into the rel's
2046 : : * baserestrictinfo.
2047 : : *
2048 : : * In inheritance cases, we only consider quals attached to the parent rel
2049 : : * here; they will be valid for all children too, so it's okay to consider
2050 : : * them for purposes like equivalence class creation. Quals attached to
2051 : : * individual child rels will be dealt with during path creation.
2052 : : */
2053 : : static void
3419 2054 : 2747 : process_security_barrier_quals(PlannerInfo *root,
2055 : : int rti, JoinTreeItem *jtitem)
2056 : : {
2057 : 2747 : RangeTblEntry *rte = root->simple_rte_array[rti];
2058 : 2747 : Index security_level = 0;
2059 : : ListCell *lc;
2060 : :
2061 : : /*
2062 : : * Each element of the securityQuals list has been preprocessed into an
2063 : : * implicitly-ANDed list of clauses. All the clauses in a given sublist
2064 : : * should get the same security level, but successive sublists get higher
2065 : : * levels.
2066 : : */
2067 [ + + + + : 5512 : foreach(lc, rte->securityQuals)
+ + ]
2068 : : {
2069 : 2765 : List *qualset = (List *) lfirst(lc);
2070 : :
2071 : : /*
2072 : : * We cheat to the extent of passing ojscope = qualscope rather than
2073 : : * its more logical value of NULL. The only effect this has is to
2074 : : * force a Var-free qual to be evaluated at the rel rather than being
2075 : : * pushed up to top of tree, which we don't want.
2076 : : */
1216 2077 : 2765 : distribute_quals_to_rels(root, qualset,
2078 : : jtitem,
2079 : : NULL,
2080 : : security_level,
2081 : : jtitem->qualscope,
2082 : : jtitem->qualscope,
2083 : : NULL,
2084 : : NULL,
2085 : : true,
2086 : : false, false, /* not clones */
2087 : : NULL);
3419 2088 : 2765 : security_level++;
2089 : : }
2090 : :
2091 : : /* Assert that qual_security_level is higher than anything we just used */
2092 [ - + ]: 2747 : Assert(security_level <= root->qual_security_level);
2093 : 2747 : }
2094 : :
2095 : : /*
2096 : : * mark_rels_nulled_by_join
2097 : : * Fill RelOptInfo.nulling_relids of baserels nulled by this outer join
2098 : : *
2099 : : * Inputs:
2100 : : * ojrelid: RT index of the join RTE (must not be 0)
2101 : : * lower_rels: the base+OJ Relids syntactically below nullable side of join
2102 : : */
2103 : : static void
1216 2104 : 35758 : mark_rels_nulled_by_join(PlannerInfo *root, Index ojrelid,
2105 : : Relids lower_rels)
2106 : : {
2107 : 35758 : int relid = -1;
2108 : :
2109 [ + + ]: 73774 : while ((relid = bms_next_member(lower_rels, relid)) > 0)
2110 : : {
2111 : 38016 : RelOptInfo *rel = root->simple_rel_array[relid];
2112 : :
2113 : : /* ignore the RTE_GROUP RTE */
627 rguo@postgresql.org 2114 [ - + ]: 38016 : if (relid == root->group_rtindex)
627 rguo@postgresql.org 2115 :UBC 0 : continue;
2116 : :
1216 tgl@sss.pgh.pa.us 2117 [ + + ]:CBC 38016 : if (rel == NULL) /* must be an outer join */
2118 : : {
2119 [ - + ]: 641 : Assert(bms_is_member(relid, root->outer_join_rels));
2120 : 641 : continue;
2121 : : }
2122 : 37375 : rel->nulling_relids = bms_add_member(rel->nulling_relids, ojrelid);
2123 : : }
2124 : 35758 : }
2125 : :
2126 : : /*
2127 : : * make_outerjoininfo
2128 : : * Build a SpecialJoinInfo for the current outer join
2129 : : *
2130 : : * Inputs:
2131 : : * left_rels: the base+OJ Relids syntactically on outer side of join
2132 : : * right_rels: the base+OJ Relids syntactically on inner side of join
2133 : : * inner_join_rels: base+OJ Relids participating in inner joins below this one
2134 : : * jointype: what it says (must always be LEFT, FULL, SEMI, or ANTI)
2135 : : * ojrelid: RT index of the join RTE (0 for SEMI, which isn't in the RT list)
2136 : : * clause: the outer join's join condition (in implicit-AND format)
2137 : : *
2138 : : * The node should eventually be appended to root->join_info_list, but we
2139 : : * do not do that here.
2140 : : *
2141 : : * Note: we assume that this function is invoked bottom-up, so that
2142 : : * root->join_info_list already contains entries for all outer joins that are
2143 : : * syntactically below this one.
2144 : : */
2145 : : static SpecialJoinInfo *
7466 2146 : 43825 : make_outerjoininfo(PlannerInfo *root,
2147 : : Relids left_rels, Relids right_rels,
2148 : : Relids inner_join_rels,
2149 : : JoinType jointype, Index ojrelid,
2150 : : List *clause)
2151 : : {
6498 2152 : 43825 : SpecialJoinInfo *sjinfo = makeNode(SpecialJoinInfo);
2153 : : Relids clause_relids;
2154 : : Relids strict_relids;
2155 : : Relids min_lefthand;
2156 : : Relids min_righthand;
2157 : : Relids commute_below_l;
2158 : : Relids commute_below_r;
2159 : : ListCell *l;
2160 : :
2161 : : /*
2162 : : * We should not see RIGHT JOIN here because left/right were switched
2163 : : * earlier
2164 : : */
2165 [ - + ]: 43825 : Assert(jointype != JOIN_INNER);
2166 [ - + ]: 43825 : Assert(jointype != JOIN_RIGHT);
2167 : :
2168 : : /*
2169 : : * Presently the executor cannot support FOR [KEY] UPDATE/SHARE marking of
2170 : : * rels appearing on the nullable side of an outer join. (It's somewhat
2171 : : * unclear what that would mean, anyway: what should we mark when a result
2172 : : * row is generated from no element of the nullable relation?) So,
2173 : : * complain if any nullable rel is FOR [KEY] UPDATE/SHARE.
2174 : : *
2175 : : * You might be wondering why this test isn't made far upstream in the
2176 : : * parser. It's because the parser hasn't got enough info --- consider
2177 : : * FOR UPDATE applied to a view. Only after rewriting and flattening do
2178 : : * we know whether the view contains an outer join.
2179 : : *
2180 : : * We use the original RowMarkClause list here; the PlanRowMark list would
2181 : : * list everything.
2182 : : */
7204 2183 [ + + + + : 43847 : foreach(l, root->parse->rowMarks)
+ + ]
2184 : : {
2185 : 22 : RowMarkClause *rc = (RowMarkClause *) lfirst(l);
2186 : :
2187 [ + - + + ]: 22 : if (bms_is_member(rc->rti, right_rels) ||
6498 2188 [ - + ]: 4 : (jointype == JOIN_FULL && bms_is_member(rc->rti, left_rels)))
7204 tgl@sss.pgh.pa.us 2189 [ # # ]:UBC 0 : ereport(ERROR,
2190 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2191 : : /*------
2192 : : translator: %s is a SQL row locking clause such as FOR UPDATE */
2193 : : errmsg("%s cannot be applied to the nullable side of an outer join",
2194 : : LCS_asString(rc->strength))));
2195 : : }
2196 : :
6498 tgl@sss.pgh.pa.us 2197 :CBC 43825 : sjinfo->syn_lefthand = left_rels;
2198 : 43825 : sjinfo->syn_righthand = right_rels;
2199 : 43825 : sjinfo->jointype = jointype;
1216 2200 : 43825 : sjinfo->ojrelid = ojrelid;
2201 : : /* these fields may get added to later: */
2202 : 43825 : sjinfo->commute_above_l = NULL;
2203 : 43825 : sjinfo->commute_above_r = NULL;
1109 2204 : 43825 : sjinfo->commute_below_l = NULL;
2205 : 43825 : sjinfo->commute_below_r = NULL;
2206 : :
1955 2207 : 43825 : compute_semijoin_info(root, sjinfo, clause);
2208 : :
2209 : : /* If it's a full join, no need to be very smart */
6498 2210 [ + + ]: 43825 : if (jointype == JOIN_FULL)
2211 : : {
2212 : 821 : sjinfo->min_lefthand = bms_copy(left_rels);
2213 : 821 : sjinfo->min_righthand = bms_copy(right_rels);
3265 2214 : 821 : sjinfo->lhs_strict = false; /* don't care about this */
6498 2215 : 821 : return sjinfo;
2216 : : }
2217 : :
2218 : : /*
2219 : : * Retrieve all relids mentioned within the join clause.
2220 : : */
1955 2221 : 43004 : clause_relids = pull_varnos(root, (Node *) clause);
2222 : :
2223 : : /*
2224 : : * For which relids is the clause strict, ie, it cannot succeed if the
2225 : : * rel's columns are all NULL?
2226 : : */
6498 2227 : 43004 : strict_relids = find_nonnullable_rels((Node *) clause);
2228 : :
2229 : : /* Remember whether the clause is strict for any LHS relations */
2230 : 43004 : sjinfo->lhs_strict = bms_overlap(strict_relids, left_rels);
2231 : :
2232 : : /*
2233 : : * Required LHS always includes the LHS rels mentioned in the clause. We
2234 : : * may have to add more rels based on lower outer joins; see below.
2235 : : */
6847 2236 : 43004 : min_lefthand = bms_intersect(clause_relids, left_rels);
2237 : :
2238 : : /*
2239 : : * Similarly for required RHS. But here, we must also include any lower
2240 : : * inner joins, to ensure we don't try to commute with any of them.
2241 : : */
2242 : 43004 : min_righthand = bms_int_members(bms_union(clause_relids, inner_join_rels),
2243 : : right_rels);
2244 : :
2245 : : /*
2246 : : * Now check previous outer joins for ordering restrictions.
2247 : : *
2248 : : * commute_below_l and commute_below_r accumulate the relids of lower
2249 : : * outer joins that we think this one can commute with. These decisions
2250 : : * are just tentative within this loop, since we might find an
2251 : : * intermediate outer join that prevents commutation. Surviving relids
2252 : : * will get merged into the SpecialJoinInfo structs afterwards.
2253 : : */
1210 2254 : 43004 : commute_below_l = commute_below_r = NULL;
6498 2255 [ + + + + : 55938 : foreach(l, root->join_info_list)
+ + ]
2256 : : {
2257 : 12934 : SpecialJoinInfo *otherinfo = (SpecialJoinInfo *) lfirst(l);
2258 : : bool have_unsafe_phvs;
2259 : :
2260 : : /*
2261 : : * A full join is an optimization barrier: we can't associate into or
2262 : : * out of it. Hence, if it overlaps either LHS or RHS of the current
2263 : : * rel, expand that side's min relset to cover the whole full join.
2264 : : */
2265 [ + + ]: 12934 : if (otherinfo->jointype == JOIN_FULL)
2266 : : {
1210 2267 [ - + ]: 50 : Assert(otherinfo->ojrelid != 0);
3691 2268 [ + + - + ]: 75 : if (bms_overlap(left_rels, otherinfo->syn_lefthand) ||
2269 : 25 : bms_overlap(left_rels, otherinfo->syn_righthand))
2270 : : {
2271 : 25 : min_lefthand = bms_add_members(min_lefthand,
2272 : 25 : otherinfo->syn_lefthand);
2273 : 25 : min_lefthand = bms_add_members(min_lefthand,
2274 : 25 : otherinfo->syn_righthand);
1210 2275 : 25 : min_lefthand = bms_add_member(min_lefthand,
2276 : 25 : otherinfo->ojrelid);
2277 : : }
3691 2278 [ + + - + ]: 75 : if (bms_overlap(right_rels, otherinfo->syn_lefthand) ||
2279 : 25 : bms_overlap(right_rels, otherinfo->syn_righthand))
2280 : : {
2281 : 25 : min_righthand = bms_add_members(min_righthand,
2282 : 25 : otherinfo->syn_lefthand);
2283 : 25 : min_righthand = bms_add_members(min_righthand,
2284 : 25 : otherinfo->syn_righthand);
1210 2285 : 25 : min_righthand = bms_add_member(min_righthand,
2286 : 25 : otherinfo->ojrelid);
2287 : : }
2288 : : /* Needn't do anything else with the full join */
7466 2289 : 50 : continue;
2290 : : }
2291 : :
2292 : : /*
2293 : : * If our join condition contains any PlaceHolderVars that need to be
2294 : : * evaluated above the lower OJ, then we can't commute with it.
2295 : : */
1216 2296 [ + + ]: 12884 : if (otherinfo->ojrelid != 0)
2297 : : have_unsafe_phvs =
2298 : 12658 : contain_placeholder_references_to(root,
2299 : : (Node *) clause,
2300 : 12658 : otherinfo->ojrelid);
2301 : : else
2302 : 226 : have_unsafe_phvs = false;
2303 : :
2304 : : /*
2305 : : * For a lower OJ in our LHS, if our join condition uses the lower
2306 : : * join's RHS and is not strict for that rel, we must preserve the
2307 : : * ordering of the two OJs, so add lower OJ's full syntactic relset to
2308 : : * min_lefthand. (We must use its full syntactic relset, not just its
2309 : : * min_lefthand + min_righthand. This is because there might be other
2310 : : * OJs below this one that this one can commute with, but we cannot
2311 : : * commute with them if we don't with this one.) Also, if we have
2312 : : * unsafe PHVs or the current join is a semijoin or antijoin, we must
2313 : : * preserve ordering regardless of strictness.
2314 : : *
2315 : : * Note: I believe we have to insist on being strict for at least one
2316 : : * rel in the lower OJ's min_righthand, not its whole syn_righthand.
2317 : : *
2318 : : * When we don't need to preserve ordering, check to see if outer join
2319 : : * identity 3 applies, and if so, remove the lower OJ's ojrelid from
2320 : : * our min_lefthand so that commutation is allowed.
2321 : : */
6301 2322 [ + + ]: 12884 : if (bms_overlap(left_rels, otherinfo->syn_righthand))
2323 : : {
2324 [ + + + + ]: 12183 : if (bms_overlap(clause_relids, otherinfo->syn_righthand) &&
1216 2325 [ + - ]: 2731 : (have_unsafe_phvs ||
2326 [ + - ]: 2731 : jointype == JOIN_SEMI || jointype == JOIN_ANTI ||
6301 2327 [ + + ]: 2731 : !bms_overlap(strict_relids, otherinfo->min_righthand)))
2328 : : {
2329 : : /* Preserve ordering */
2330 : 35 : min_lefthand = bms_add_members(min_lefthand,
2331 : 35 : otherinfo->syn_lefthand);
2332 : 35 : min_lefthand = bms_add_members(min_lefthand,
2333 : 35 : otherinfo->syn_righthand);
1216 2334 [ + - ]: 35 : if (otherinfo->ojrelid != 0)
2335 : 35 : min_lefthand = bms_add_member(min_lefthand,
2336 : 35 : otherinfo->ojrelid);
2337 : : }
2338 [ + + ]: 12148 : else if (jointype == JOIN_LEFT &&
2339 [ + + + + ]: 23389 : otherinfo->jointype == JOIN_LEFT &&
1205 2340 : 11691 : bms_overlap(strict_relids, otherinfo->min_righthand) &&
2341 [ + + ]: 2701 : !bms_overlap(clause_relids, otherinfo->syn_lefthand))
2342 : : {
2343 : : /* Identity 3 applies, so remove the ordering restriction */
1216 2344 : 2662 : min_lefthand = bms_del_member(min_lefthand, otherinfo->ojrelid);
2345 : : /* Record the (still tentative) commutability relationship */
2346 : : commute_below_l =
1210 2347 : 2662 : bms_add_member(commute_below_l, otherinfo->ojrelid);
2348 : : }
2349 : : }
2350 : :
2351 : : /*
2352 : : * For a lower OJ in our RHS, if our join condition does not use the
2353 : : * lower join's RHS and the lower OJ's join condition is strict, we
2354 : : * can interchange the ordering of the two OJs; otherwise we must add
2355 : : * the lower OJ's full syntactic relset to min_righthand.
2356 : : *
2357 : : * Also, if our join condition does not use the lower join's LHS
2358 : : * either, force the ordering to be preserved. Otherwise we can end
2359 : : * up with SpecialJoinInfos with identical min_righthands, which can
2360 : : * confuse join_is_legal (see discussion in backend/optimizer/README).
2361 : : *
2362 : : * Also, we must preserve ordering anyway if we have unsafe PHVs, or
2363 : : * if either this join or the lower OJ is a semijoin or antijoin.
2364 : : *
2365 : : * When we don't need to preserve ordering, check to see if outer join
2366 : : * identity 3 applies, and if so, remove the lower OJ's ojrelid from
2367 : : * our min_righthand so that commutation is allowed.
2368 : : */
6847 2369 [ + + ]: 12884 : if (bms_overlap(right_rels, otherinfo->syn_righthand))
2370 : : {
2371 [ + + ]: 636 : if (bms_overlap(clause_relids, otherinfo->syn_righthand) ||
3950 2372 [ + + + - ]: 596 : !bms_overlap(clause_relids, otherinfo->min_lefthand) ||
1216 2373 [ + + ]: 330 : have_unsafe_phvs ||
6232 2374 [ + + ]: 262 : jointype == JOIN_SEMI ||
4053 2375 : 237 : jointype == JOIN_ANTI ||
6157 2376 [ + + ]: 237 : otherinfo->jointype == JOIN_SEMI ||
6301 2377 [ + - ]: 203 : otherinfo->jointype == JOIN_ANTI ||
1216 2378 [ + + ]: 203 : !otherinfo->lhs_strict)
2379 : : {
2380 : : /* Preserve ordering */
6847 2381 : 453 : min_righthand = bms_add_members(min_righthand,
2382 : 453 : otherinfo->syn_lefthand);
2383 : 453 : min_righthand = bms_add_members(min_righthand,
2384 : 453 : otherinfo->syn_righthand);
1216 2385 [ + + ]: 453 : if (otherinfo->ojrelid != 0)
2386 : 346 : min_righthand = bms_add_member(min_righthand,
2387 : 346 : otherinfo->ojrelid);
2388 : : }
2389 [ + - ]: 183 : else if (jointype == JOIN_LEFT &&
2390 [ + - ]: 183 : otherinfo->jointype == JOIN_LEFT &&
2391 [ + - ]: 183 : otherinfo->lhs_strict)
2392 : : {
2393 : : /* Identity 3 applies, so remove the ordering restriction */
2394 : 183 : min_righthand = bms_del_member(min_righthand,
2395 : 183 : otherinfo->ojrelid);
2396 : : /* Record the (still tentative) commutability relationship */
2397 : : commute_below_r =
1210 2398 : 183 : bms_add_member(commute_below_r, otherinfo->ojrelid);
2399 : : }
2400 : : }
2401 : : }
2402 : :
2403 : : /*
2404 : : * Examine PlaceHolderVars. If a PHV is supposed to be evaluated within
2405 : : * this join's nullable side, then ensure that min_righthand contains the
2406 : : * full eval_at set of the PHV. This ensures that the PHV actually can be
2407 : : * evaluated within the RHS. Note that this works only because we should
2408 : : * already have determined the final eval_at level for any PHV
2409 : : * syntactically within this join.
2410 : : */
5723 2411 [ + + + + : 44160 : foreach(l, root->placeholder_list)
+ + ]
2412 : : {
2413 : 1156 : PlaceHolderInfo *phinfo = (PlaceHolderInfo *) lfirst(l);
2414 : 1156 : Relids ph_syn_level = phinfo->ph_var->phrels;
2415 : :
2416 : : /* Ignore placeholder if it didn't syntactically come from RHS */
2417 [ + + ]: 1156 : if (!bms_is_subset(ph_syn_level, right_rels))
2418 : 416 : continue;
2419 : :
2420 : : /* Else, prevent join from being formed before we eval the PHV */
2421 : 740 : min_righthand = bms_add_members(min_righthand, phinfo->ph_eval_at);
2422 : : }
2423 : :
2424 : : /*
2425 : : * If we found nothing to put in min_lefthand, punt and make it the full
2426 : : * LHS, to avoid having an empty min_lefthand which will confuse later
2427 : : * processing. (We don't try to be smart about such cases, just correct.)
2428 : : * Likewise for min_righthand.
2429 : : */
6847 2430 [ + + ]: 43004 : if (bms_is_empty(min_lefthand))
2431 : 1233 : min_lefthand = bms_copy(left_rels);
3950 2432 [ + + ]: 43004 : if (bms_is_empty(min_righthand))
2433 : 821 : min_righthand = bms_copy(right_rels);
2434 : :
2435 : : /* Now they'd better be nonempty */
6847 2436 [ - + ]: 43004 : Assert(!bms_is_empty(min_lefthand));
2437 [ - + ]: 43004 : Assert(!bms_is_empty(min_righthand));
2438 : : /* Shouldn't overlap either */
2439 [ - + ]: 43004 : Assert(!bms_overlap(min_lefthand, min_righthand));
2440 : :
6498 2441 : 43004 : sjinfo->min_lefthand = min_lefthand;
2442 : 43004 : sjinfo->min_righthand = min_righthand;
2443 : :
2444 : : /*
2445 : : * Now that we've identified the correct min_lefthand and min_righthand,
2446 : : * any commute_below_l or commute_below_r relids that have not gotten
2447 : : * added back into those sets (due to intervening outer joins) are indeed
2448 : : * commutable with this one.
2449 : : *
2450 : : * First, delete any subsequently-added-back relids (this is easier than
2451 : : * maintaining commute_below_l/r precisely through all the above).
2452 : : */
1109 2453 : 43004 : commute_below_l = bms_del_members(commute_below_l, min_lefthand);
2454 : 43004 : commute_below_r = bms_del_members(commute_below_r, min_righthand);
2455 : :
2456 : : /* Anything left? */
1210 2457 [ + + + + ]: 43004 : if (commute_below_l || commute_below_r)
2458 : : {
2459 : : /* Yup, so we must update the derived data in the SpecialJoinInfos */
1109 2460 : 2780 : sjinfo->commute_below_l = commute_below_l;
2461 : 2780 : sjinfo->commute_below_r = commute_below_r;
2462 [ + - + + : 6201 : foreach(l, root->join_info_list)
+ + ]
2463 : : {
2464 : 3421 : SpecialJoinInfo *otherinfo = (SpecialJoinInfo *) lfirst(l);
2465 : :
2466 [ + + ]: 3421 : if (bms_is_member(otherinfo->ojrelid, commute_below_l))
2467 : 2662 : otherinfo->commute_above_l =
2468 : 2662 : bms_add_member(otherinfo->commute_above_l, ojrelid);
2469 [ + + ]: 759 : else if (bms_is_member(otherinfo->ojrelid, commute_below_r))
2470 : 158 : otherinfo->commute_above_r =
2471 : 158 : bms_add_member(otherinfo->commute_above_r, ojrelid);
2472 : : }
2473 : : }
2474 : :
6498 2475 : 43004 : return sjinfo;
2476 : : }
2477 : :
2478 : : /*
2479 : : * compute_semijoin_info
2480 : : * Fill semijoin-related fields of a new SpecialJoinInfo
2481 : : *
2482 : : * Note: this relies on only the jointype and syn_righthand fields of the
2483 : : * SpecialJoinInfo; the rest may not be set yet.
2484 : : */
2485 : : static void
1955 2486 : 43825 : compute_semijoin_info(PlannerInfo *root, SpecialJoinInfo *sjinfo, List *clause)
2487 : : {
2488 : : List *semi_operators;
2489 : : List *semi_rhs_exprs;
2490 : : bool all_btree;
2491 : : bool all_hash;
2492 : : ListCell *lc;
2493 : :
2494 : : /* Initialize semijoin-related fields in case we can't unique-ify */
4098 2495 : 43825 : sjinfo->semi_can_btree = false;
2496 : 43825 : sjinfo->semi_can_hash = false;
2497 : 43825 : sjinfo->semi_operators = NIL;
2498 : 43825 : sjinfo->semi_rhs_exprs = NIL;
2499 : :
2500 : : /* Nothing more to do if it's not a semijoin */
2501 [ + + ]: 43825 : if (sjinfo->jointype != JOIN_SEMI)
2502 : 39805 : return;
2503 : :
2504 : : /*
2505 : : * Look to see whether the semijoin's join quals consist of AND'ed
2506 : : * equality operators, with (only) RHS variables on only one side of each
2507 : : * one. If so, we can figure out how to enforce uniqueness for the RHS.
2508 : : *
2509 : : * Note that the input clause list is the list of quals that are
2510 : : * *syntactically* associated with the semijoin, which in practice means
2511 : : * the synthesized comparison list for an IN or the WHERE of an EXISTS.
2512 : : * Particularly in the latter case, it might contain clauses that aren't
2513 : : * *semantically* associated with the join, but refer to just one side or
2514 : : * the other. We can ignore such clauses here, as they will just drop
2515 : : * down to be processed within one side or the other. (It is okay to
2516 : : * consider only the syntactically-associated clauses here because for a
2517 : : * semijoin, no higher-level quals could refer to the RHS, and so there
2518 : : * can be no other quals that are semantically associated with this join.
2519 : : * We do things this way because it is useful to have the set of potential
2520 : : * unique-ification expressions before we can extract the list of quals
2521 : : * that are actually semantically associated with the particular join.)
2522 : : *
2523 : : * Note that the semi_operators list consists of the joinqual operators
2524 : : * themselves (but commuted if needed to put the RHS value on the right).
2525 : : * These could be cross-type operators, in which case the operator
2526 : : * actually needed for uniqueness is a related single-type operator. We
2527 : : * assume here that that operator will be available from the btree or hash
2528 : : * opclass when the time comes ... if not, create_unique_plan() will fail.
2529 : : */
2530 : 4020 : semi_operators = NIL;
2531 : 4020 : semi_rhs_exprs = NIL;
2532 : 4020 : all_btree = true;
2533 : 4020 : all_hash = enable_hashagg; /* don't consider hash if not enabled */
2534 [ + - + + : 8333 : foreach(lc, clause)
+ + ]
2535 : : {
2536 : 4402 : OpExpr *op = (OpExpr *) lfirst(lc);
2537 : : Oid opno;
2538 : : Node *left_expr;
2539 : : Node *right_expr;
2540 : : Relids left_varnos;
2541 : : Relids right_varnos;
2542 : : Relids all_varnos;
2543 : : Oid opinputtype;
2544 : :
2545 : : /* Is it a binary opclause? */
2546 [ + + - + ]: 8720 : if (!IsA(op, OpExpr) ||
2547 : 4318 : list_length(op->args) != 2)
2548 : : {
2549 : : /* No, but does it reference both sides? */
1955 2550 : 84 : all_varnos = pull_varnos(root, (Node *) op);
4098 2551 [ + + + + ]: 158 : if (!bms_overlap(all_varnos, sjinfo->syn_righthand) ||
2552 : 74 : bms_is_subset(all_varnos, sjinfo->syn_righthand))
2553 : : {
2554 : : /*
2555 : : * Clause refers to only one rel, so ignore it --- unless it
2556 : : * contains volatile functions, in which case we'd better
2557 : : * punt.
2558 : : */
2559 [ - + ]: 74 : if (contain_volatile_functions((Node *) op))
2560 : 89 : return;
2561 : 74 : continue;
2562 : : }
2563 : : /* Non-operator clause referencing both sides, must punt */
2564 : 10 : return;
2565 : : }
2566 : :
2567 : : /* Extract data from binary opclause */
2568 : 4318 : opno = op->opno;
2569 : 4318 : left_expr = linitial(op->args);
2570 : 4318 : right_expr = lsecond(op->args);
1955 2571 : 4318 : left_varnos = pull_varnos(root, left_expr);
2572 : 4318 : right_varnos = pull_varnos(root, right_expr);
4098 2573 : 4318 : all_varnos = bms_union(left_varnos, right_varnos);
2574 : 4318 : opinputtype = exprType(left_expr);
2575 : :
2576 : : /* Does it reference both sides? */
2577 [ + + + + ]: 8622 : if (!bms_overlap(all_varnos, sjinfo->syn_righthand) ||
2578 : 4304 : bms_is_subset(all_varnos, sjinfo->syn_righthand))
2579 : : {
2580 : : /*
2581 : : * Clause refers to only one rel, so ignore it --- unless it
2582 : : * contains volatile functions, in which case we'd better punt.
2583 : : */
2584 [ - + ]: 93 : if (contain_volatile_functions((Node *) op))
4098 tgl@sss.pgh.pa.us 2585 :UBC 0 : return;
4098 tgl@sss.pgh.pa.us 2586 :CBC 93 : continue;
2587 : : }
2588 : :
2589 : : /* check rel membership of arguments */
2590 [ + - + + ]: 8450 : if (!bms_is_empty(right_varnos) &&
2591 : 4225 : bms_is_subset(right_varnos, sjinfo->syn_righthand) &&
2592 [ + - ]: 3893 : !bms_overlap(left_varnos, sjinfo->syn_righthand))
2593 : : {
2594 : : /* typical case, right_expr is RHS variable */
2595 : : }
2596 [ + - + + ]: 664 : else if (!bms_is_empty(left_varnos) &&
2597 : 332 : bms_is_subset(left_varnos, sjinfo->syn_righthand) &&
2598 [ + - ]: 327 : !bms_overlap(right_varnos, sjinfo->syn_righthand))
2599 : : {
2600 : : /* flipped case, left_expr is RHS variable */
2601 : 327 : opno = get_commutator(opno);
2602 [ - + ]: 327 : if (!OidIsValid(opno))
4098 tgl@sss.pgh.pa.us 2603 :UBC 0 : return;
4098 tgl@sss.pgh.pa.us 2604 :CBC 327 : right_expr = left_expr;
2605 : : }
2606 : : else
2607 : : {
2608 : : /* mixed membership of args, punt */
2609 : 5 : return;
2610 : : }
2611 : :
2612 : : /* all operators must be btree equality or hash equality */
2613 [ + - ]: 4220 : if (all_btree)
2614 : : {
2615 : : /* oprcanmerge is considered a hint... */
2616 [ + + - + ]: 8366 : if (!op_mergejoinable(opno, opinputtype) ||
2617 : 4146 : get_mergejoin_opfamilies(opno) == NIL)
2618 : 74 : all_btree = false;
2619 : : }
2620 [ + + ]: 4220 : if (all_hash)
2621 : : {
2622 : : /* ... but oprcanhash had better be correct */
2623 [ + + ]: 4166 : if (!op_hashjoinable(opno, opinputtype))
2624 : 74 : all_hash = false;
2625 : : }
2626 [ + + + - ]: 4220 : if (!(all_btree || all_hash))
2627 : 74 : return;
2628 : :
2629 : : /* so far so good, keep building lists */
2630 : 4146 : semi_operators = lappend_oid(semi_operators, opno);
2631 : 4146 : semi_rhs_exprs = lappend(semi_rhs_exprs, copyObject(right_expr));
2632 : : }
2633 : :
2634 : : /* Punt if we didn't find at least one column to unique-ify */
2635 [ + + ]: 3931 : if (semi_rhs_exprs == NIL)
2636 : 10 : return;
2637 : :
2638 : : /*
2639 : : * The expressions we'd need to unique-ify mustn't be volatile.
2640 : : */
2641 [ - + ]: 3921 : if (contain_volatile_functions((Node *) semi_rhs_exprs))
4098 tgl@sss.pgh.pa.us 2642 :UBC 0 : return;
2643 : :
2644 : : /*
2645 : : * If we get here, we can unique-ify the semijoin's RHS using at least one
2646 : : * of sorting and hashing. Save the information about how to do that.
2647 : : */
4098 tgl@sss.pgh.pa.us 2648 :CBC 3921 : sjinfo->semi_can_btree = all_btree;
2649 : 3921 : sjinfo->semi_can_hash = all_hash;
2650 : 3921 : sjinfo->semi_operators = semi_operators;
2651 : 3921 : sjinfo->semi_rhs_exprs = semi_rhs_exprs;
2652 : : }
2653 : :
2654 : : /*
2655 : : * deconstruct_distribute_oj_quals
2656 : : * Adjust LEFT JOIN quals to be suitable for commuted-left-join cases,
2657 : : * then push them into the joinqual lists and EquivalenceClass structures.
2658 : : *
2659 : : * This runs immediately after we've completed the deconstruct_distribute scan.
2660 : : * jtitems contains all the JoinTreeItems (in depth-first order), and jtitem
2661 : : * is one that has postponed oj_joinclauses to deal with.
2662 : : */
2663 : : static void
1216 2664 : 31841 : deconstruct_distribute_oj_quals(PlannerInfo *root,
2665 : : List *jtitems,
2666 : : JoinTreeItem *jtitem)
2667 : : {
2668 : 31841 : SpecialJoinInfo *sjinfo = jtitem->sjinfo;
2669 : : Relids qualscope,
2670 : : ojscope,
2671 : : nonnullable_rels;
2672 : :
2673 : : /* Recompute syntactic and semantic scopes of this left join */
2674 : 31841 : qualscope = bms_union(sjinfo->syn_lefthand, sjinfo->syn_righthand);
2675 : 31841 : qualscope = bms_add_member(qualscope, sjinfo->ojrelid);
2676 : 31841 : ojscope = bms_union(sjinfo->min_lefthand, sjinfo->min_righthand);
2677 : 31841 : nonnullable_rels = sjinfo->syn_lefthand;
2678 : :
2679 : : /*
2680 : : * If this join can commute with any other ones per outer-join identity 3,
2681 : : * and it is the one providing the join clause with flexible semantics,
2682 : : * then we have to generate variants of the join clause with different
2683 : : * nullingrels labeling. Otherwise, just push out the postponed clause
2684 : : * as-is.
2685 : : */
2686 [ - + ]: 31841 : Assert(sjinfo->lhs_strict); /* else we shouldn't be here */
1109 2687 [ + + + + ]: 31841 : if (sjinfo->commute_above_r || sjinfo->commute_below_l)
1216 2688 : 2790 : {
2689 : : Relids joins_above;
2690 : : Relids joins_below;
2691 : : Relids incompatible_joins;
2692 : : Relids joins_so_far;
2693 : : List *quals;
2694 : : int save_last_rinfo_serial;
2695 : : ListCell *lc;
2696 : :
2697 : : /* Identify the outer joins this one commutes with */
2698 : 2790 : joins_above = sjinfo->commute_above_r;
1109 2699 : 2790 : joins_below = sjinfo->commute_below_l;
2700 : :
2701 : : /*
2702 : : * Generate qual variants with different sets of nullingrels bits.
2703 : : *
2704 : : * We only need bit-sets that correspond to the successively less
2705 : : * deeply syntactically-nested subsets of this join and its
2706 : : * commutators. That's true first because obviously only those forms
2707 : : * of the Vars and PHVs could appear elsewhere in the query, and
2708 : : * second because the outer join identities do not provide a way to
2709 : : * re-order such joins in a way that would require different marking.
2710 : : * (That is, while the current join may commute with several others,
2711 : : * none of those others can commute with each other.) To visit the
2712 : : * interesting joins in syntactic nesting order, we rely on the
2713 : : * jtitems list to be ordered that way.
2714 : : *
2715 : : * We first strip out all the nullingrels bits corresponding to
2716 : : * commuting joins below this one, and then successively put them back
2717 : : * as we crawl up the join stack.
2718 : : */
1216 2719 : 2790 : quals = jtitem->oj_joinclauses;
2720 [ + + ]: 2790 : if (!bms_is_empty(joins_below))
2721 : 2632 : quals = (List *) remove_nulling_relids((Node *) quals,
2722 : : joins_below,
2723 : : NULL);
2724 : :
2725 : : /*
2726 : : * We'll need to mark the lower versions of the quals as not safe to
2727 : : * apply above not-yet-processed joins of the stack. This prevents
2728 : : * possibly applying a cloned qual at the wrong join level.
2729 : : */
1101 2730 : 2790 : incompatible_joins = bms_union(joins_below, joins_above);
2731 : 2790 : incompatible_joins = bms_add_member(incompatible_joins,
2732 : 2790 : sjinfo->ojrelid);
2733 : :
2734 : : /*
2735 : : * Each time we produce RestrictInfo(s) from these quals, reset the
2736 : : * last_rinfo_serial counter, so that the RestrictInfos for the "same"
2737 : : * qual condition get identical serial numbers. (This relies on the
2738 : : * fact that we're not changing the qual list in any way that'd affect
2739 : : * the number of RestrictInfos built from it.) This'll allow us to
2740 : : * detect duplicative qual usage later.
2741 : : */
1216 2742 : 2790 : save_last_rinfo_serial = root->last_rinfo_serial;
2743 : :
2744 : 2790 : joins_so_far = NULL;
2745 [ + - + + : 24646 : foreach(lc, jtitems)
+ + ]
2746 : : {
2747 : 21856 : JoinTreeItem *otherjtitem = (JoinTreeItem *) lfirst(lc);
2748 : 21856 : SpecialJoinInfo *othersj = otherjtitem->sjinfo;
2749 : 21856 : bool below_sjinfo = false;
2750 : 21856 : bool above_sjinfo = false;
2751 : : Relids this_qualscope;
2752 : : Relids this_ojscope;
2753 : : bool allow_equivalence,
2754 : : has_clone,
2755 : : is_clone;
2756 : :
2757 [ + + ]: 21856 : if (othersj == NULL)
2758 : 15437 : continue; /* not an outer-join item, ignore */
2759 : :
2760 [ + + ]: 6419 : if (bms_is_member(othersj->ojrelid, joins_below))
2761 : : {
2762 : : /* othersj commutes with sjinfo from below left */
2763 : 2662 : below_sjinfo = true;
2764 : : }
2765 [ + + ]: 3757 : else if (othersj == sjinfo)
2766 : : {
2767 : : /* found our join in syntactic order */
2768 [ - + ]: 2790 : Assert(bms_equal(joins_so_far, joins_below));
2769 : : }
2770 [ + + ]: 967 : else if (bms_is_member(othersj->ojrelid, joins_above))
2771 : : {
2772 : : /* othersj commutes with sjinfo from above */
2773 : 158 : above_sjinfo = true;
2774 : : }
2775 : : else
2776 : : {
2777 : : /* othersj is not relevant, ignore */
2778 : 809 : continue;
2779 : : }
2780 : :
2781 : : /* Reset serial counter for this version of the quals */
2782 : 5610 : root->last_rinfo_serial = save_last_rinfo_serial;
2783 : :
2784 : : /*
2785 : : * When we are looking at joins above sjinfo, we are envisioning
2786 : : * pushing sjinfo to above othersj, so add othersj's nulling bit
2787 : : * before distributing the quals. We should add it to Vars coming
2788 : : * from the current join's LHS: we want to transform the second
2789 : : * form of OJ identity 3 to the first form, in which Vars of
2790 : : * relation B will appear nulled by the syntactically-upper OJ
2791 : : * within the Pbc clause, but those of relation C will not. (In
2792 : : * the notation used by optimizer/README, we're converting a qual
2793 : : * of the form Pbc to Pb*c.) Of course, we must also remove that
2794 : : * bit from the incompatible_joins value, else we'll make a qual
2795 : : * that can't be placed anywhere.
2796 : : */
2797 [ + + ]: 5610 : if (above_sjinfo)
2798 : : {
2799 : : quals = (List *)
2800 : 158 : add_nulling_relids((Node *) quals,
1205 2801 : 158 : sjinfo->syn_lefthand,
1216 2802 : 158 : bms_make_singleton(othersj->ojrelid));
1101 2803 : 158 : incompatible_joins = bms_del_member(incompatible_joins,
2804 : 158 : othersj->ojrelid);
2805 : : }
2806 : :
2807 : : /* Compute qualscope and ojscope for this join level */
1216 2808 : 5610 : this_qualscope = bms_union(qualscope, joins_so_far);
2809 : 5610 : this_ojscope = bms_union(ojscope, joins_so_far);
2810 [ + + ]: 5610 : if (above_sjinfo)
2811 : : {
2812 : : /* othersj is not yet in joins_so_far, but we need it */
2813 : 158 : this_qualscope = bms_add_member(this_qualscope,
2814 : 158 : othersj->ojrelid);
2815 : 158 : this_ojscope = bms_add_member(this_ojscope,
2816 : 158 : othersj->ojrelid);
2817 : : /* sjinfo is in joins_so_far, and we don't want it */
2818 : 158 : this_ojscope = bms_del_member(this_ojscope,
2819 : 158 : sjinfo->ojrelid);
2820 : : }
2821 : :
2822 : : /*
2823 : : * We generate EquivalenceClasses only from the first form of the
2824 : : * quals, with the fewest nullingrels bits set. An EC made from
2825 : : * this version of the quals can be useful below the outer-join
2826 : : * nest, whereas versions with some nullingrels bits set would not
2827 : : * be. We cannot generate ECs from more than one version, or
2828 : : * we'll make nonsensical conclusions that Vars with nullingrels
2829 : : * bits set are equal to their versions without. Fortunately,
2830 : : * such ECs wouldn't be very useful anyway, because they'd equate
2831 : : * values not observable outside the join nest. (See
2832 : : * optimizer/README.)
2833 : : *
2834 : : * The first form of the quals is also the only one marked as
2835 : : * has_clone rather than is_clone.
2836 : : */
2837 : 5610 : allow_equivalence = (joins_so_far == NULL);
2838 : 5610 : has_clone = allow_equivalence;
2839 : 5610 : is_clone = !has_clone;
2840 : :
2841 : 5610 : distribute_quals_to_rels(root, quals,
2842 : : otherjtitem,
2843 : : sjinfo,
2844 : : root->qual_security_level,
2845 : : this_qualscope,
2846 : : this_ojscope, nonnullable_rels,
2847 : : bms_copy(incompatible_joins),
2848 : : allow_equivalence,
2849 : : has_clone,
2850 : : is_clone,
2851 : : NULL); /* no more postponement */
2852 : :
2853 : : /*
2854 : : * Adjust qual nulling bits for next level up, if needed. We
2855 : : * don't want to put sjinfo's own bit in at all, and if we're
2856 : : * above sjinfo then we did it already. Here, we should mark all
2857 : : * Vars coming from the lower join's RHS. (Again, we are
2858 : : * converting a qual of the form Pbc to Pb*c, but now we are
2859 : : * putting back bits that were there in the parser output and were
2860 : : * temporarily stripped above.) Update incompatible_joins too.
2861 : : */
2862 [ + + ]: 5610 : if (below_sjinfo)
2863 : : {
2864 : : quals = (List *)
2865 : 2662 : add_nulling_relids((Node *) quals,
1205 2866 : 2662 : othersj->syn_righthand,
1216 2867 : 2662 : bms_make_singleton(othersj->ojrelid));
1101 2868 : 2662 : incompatible_joins = bms_del_member(incompatible_joins,
2869 : 2662 : othersj->ojrelid);
2870 : : }
2871 : :
2872 : : /* ... and track joins processed so far */
1216 2873 : 5610 : joins_so_far = bms_add_member(joins_so_far, othersj->ojrelid);
2874 : : }
2875 : : }
2876 : : else
2877 : : {
2878 : : /* No commutation possible, just process the postponed clauses */
2879 : 29051 : distribute_quals_to_rels(root, jtitem->oj_joinclauses,
2880 : : jtitem,
2881 : : sjinfo,
2882 : : root->qual_security_level,
2883 : : qualscope,
2884 : : ojscope, nonnullable_rels,
2885 : : NULL, /* incompatible_relids */
2886 : : true, /* allow_equivalence */
2887 : : false, false, /* not clones */
2888 : : NULL); /* no more postponement */
2889 : : }
2890 : 31841 : }
2891 : :
2892 : :
2893 : : /*****************************************************************************
2894 : : *
2895 : : * QUALIFICATIONS
2896 : : *
2897 : : *****************************************************************************/
2898 : :
2899 : : /*
2900 : : * distribute_quals_to_rels
2901 : : * Convenience routine to apply distribute_qual_to_rels to each element
2902 : : * of an AND'ed list of clauses.
2903 : : */
2904 : : static void
2905 : 657077 : distribute_quals_to_rels(PlannerInfo *root, List *clauses,
2906 : : JoinTreeItem *jtitem,
2907 : : SpecialJoinInfo *sjinfo,
2908 : : Index security_level,
2909 : : Relids qualscope,
2910 : : Relids ojscope,
2911 : : Relids outerjoin_nonnullable,
2912 : : Relids incompatible_relids,
2913 : : bool allow_equivalence,
2914 : : bool has_clone,
2915 : : bool is_clone,
2916 : : List **postponed_oj_qual_list)
2917 : : {
2918 : : ListCell *lc;
2919 : :
2920 [ + + + + : 1123873 : foreach(lc, clauses)
+ + ]
2921 : : {
2922 : 466796 : Node *clause = (Node *) lfirst(lc);
2923 : :
2924 : 466796 : distribute_qual_to_rels(root, clause,
2925 : : jtitem,
2926 : : sjinfo,
2927 : : security_level,
2928 : : qualscope,
2929 : : ojscope,
2930 : : outerjoin_nonnullable,
2931 : : incompatible_relids,
2932 : : allow_equivalence,
2933 : : has_clone,
2934 : : is_clone,
2935 : : postponed_oj_qual_list);
2936 : : }
2937 : 657077 : }
2938 : :
2939 : : /*
2940 : : * distribute_qual_to_rels
2941 : : * Add clause information to either the baserestrictinfo or joininfo list
2942 : : * (depending on whether the clause is a join) of each base relation
2943 : : * mentioned in the clause. A RestrictInfo node is created and added to
2944 : : * the appropriate list for each rel. Alternatively, if the clause uses a
2945 : : * mergejoinable operator, enter its left- and right-side expressions into
2946 : : * the query's EquivalenceClasses.
2947 : : *
2948 : : * In some cases, quals will be added to parent jtitems' lateral_clauses
2949 : : * or to postponed_oj_qual_list instead of being processed right away.
2950 : : * These will be dealt with in later calls of deconstruct_distribute.
2951 : : *
2952 : : * 'clause': the qual clause to be distributed
2953 : : * 'jtitem': the JoinTreeItem for the containing jointree node
2954 : : * 'sjinfo': join's SpecialJoinInfo (NULL for an inner join or WHERE clause)
2955 : : * 'security_level': security_level to assign to the qual
2956 : : * 'qualscope': set of base+OJ rels the qual's syntactic scope covers
2957 : : * 'ojscope': NULL if not an outer-join qual, else the minimum set of base+OJ
2958 : : * rels needed to form this join
2959 : : * 'outerjoin_nonnullable': NULL if not an outer-join qual, else the set of
2960 : : * base+OJ rels appearing on the outer (nonnullable) side of the join
2961 : : * (for FULL JOIN this includes both sides of the join, and must in fact
2962 : : * equal qualscope)
2963 : : * 'incompatible_relids': the set of outer-join relid(s) that must not be
2964 : : * computed below this qual. We only bother to compute this for
2965 : : * "clone" quals, otherwise it can be left NULL.
2966 : : * 'allow_equivalence': true if it's okay to convert clause into an
2967 : : * EquivalenceClass
2968 : : * 'has_clone': has_clone property to assign to the qual
2969 : : * 'is_clone': is_clone property to assign to the qual
2970 : : * 'postponed_oj_qual_list': if not NULL, non-degenerate outer join clauses
2971 : : * should be added to this list instead of being processed (list entries
2972 : : * are just the bare clauses)
2973 : : *
2974 : : * 'qualscope' identifies what level of JOIN the qual came from syntactically.
2975 : : * 'ojscope' is needed if we decide to force the qual up to the outer-join
2976 : : * level, which will be ojscope not necessarily qualscope.
2977 : : *
2978 : : * At the time this is called, root->join_info_list must contain entries for
2979 : : * at least those special joins that are syntactically below this qual.
2980 : : * (We now need that only for detection of redundant IS NULL quals.)
2981 : : */
2982 : : static void
7664 2983 : 466796 : distribute_qual_to_rels(PlannerInfo *root, Node *clause,
2984 : : JoinTreeItem *jtitem,
2985 : : SpecialJoinInfo *sjinfo,
2986 : : Index security_level,
2987 : : Relids qualscope,
2988 : : Relids ojscope,
2989 : : Relids outerjoin_nonnullable,
2990 : : Relids incompatible_relids,
2991 : : bool allow_equivalence,
2992 : : bool has_clone,
2993 : : bool is_clone,
2994 : : List **postponed_oj_qual_list)
2995 : : {
2996 : : Relids relids;
2997 : : bool is_pushed_down;
7273 2998 : 466796 : bool pseudoconstant = false;
2999 : : bool maybe_equivalence;
3000 : : bool maybe_outer_join;
3001 : : RestrictInfo *restrictinfo;
3002 : :
3003 : : /*
3004 : : * Retrieve all relids mentioned within the clause.
3005 : : */
1955 3006 : 466796 : relids = pull_varnos(root, clause);
3007 : :
3008 : : /*
3009 : : * In ordinary SQL, a WHERE or JOIN/ON clause can't reference any rels
3010 : : * that aren't within its syntactic scope; however, if we pulled up a
3011 : : * LATERAL subquery then we might find such references in quals that have
3012 : : * been pulled up. We need to treat such quals as belonging to the join
3013 : : * level that includes every rel they reference. Although we could make
3014 : : * pull_up_subqueries() place such quals correctly to begin with, it's
3015 : : * easier to handle it here. When we find a clause that contains Vars
3016 : : * outside its syntactic scope, locate the nearest parent join level that
3017 : : * includes all the required rels and add the clause to that level's
3018 : : * lateral_clauses list. We'll process it when we reach that join level.
3019 : : */
4667 3020 [ + + ]: 466796 : if (!bms_is_subset(relids, qualscope))
3021 : : {
3022 : : JoinTreeItem *pitem;
3023 : :
3024 [ - + ]: 99 : Assert(root->hasLateralRTEs); /* shouldn't happen otherwise */
1216 3025 [ - + ]: 99 : Assert(sjinfo == NULL); /* mustn't postpone past outer join */
1211 3026 [ + - ]: 104 : for (pitem = jtitem->jti_parent; pitem; pitem = pitem->jti_parent)
3027 : : {
3028 [ + + ]: 104 : if (bms_is_subset(relids, pitem->qualscope))
3029 : : {
3030 : 99 : pitem->lateral_clauses = lappend(pitem->lateral_clauses,
3031 : : clause);
3032 : 326408 : return;
3033 : : }
3034 : :
3035 : : /*
3036 : : * We should not be postponing any quals past an outer join. If
3037 : : * this Assert fires, pull_up_subqueries() messed up.
3038 : : */
3039 [ - + ]: 5 : Assert(pitem->sjinfo == NULL);
3040 : : }
1211 tgl@sss.pgh.pa.us 3041 [ # # ]:UBC 0 : elog(ERROR, "failed to postpone qual containing lateral reference");
3042 : : }
3043 : :
3044 : : /*
3045 : : * If it's an outer-join clause, also check that relids is a subset of
3046 : : * ojscope. (This should not fail if the syntactic scope check passed.)
3047 : : */
7466 tgl@sss.pgh.pa.us 3048 [ + + - + ]:CBC 466697 : if (ojscope && !bms_is_subset(relids, ojscope))
7058 bruce@momjian.us 3049 [ # # ]:UBC 0 : elog(ERROR, "JOIN qualification cannot refer to other relations");
3050 : :
3051 : : /*
3052 : : * If the clause is variable-free, our normal heuristic for pushing it
3053 : : * down to just the mentioned rels doesn't work, because there are none.
3054 : : *
3055 : : * If the clause is an outer-join clause, we must force it to the OJ's
3056 : : * semantic level to preserve semantics.
3057 : : *
3058 : : * Otherwise, when the clause contains volatile functions, we force it to
3059 : : * be evaluated at its original syntactic level. This preserves the
3060 : : * expected semantics.
3061 : : *
3062 : : * When the clause contains no volatile functions either, it is actually a
3063 : : * pseudoconstant clause that will not change value during any one
3064 : : * execution of the plan, and hence can be used as a one-time qual in a
3065 : : * gating Result plan node. We put such a clause into the regular
3066 : : * RestrictInfo lists for the moment, but eventually createplan.c will
3067 : : * pull it out and make a gating Result node immediately above whatever
3068 : : * plan node the pseudoconstant clause is assigned to. It's usually best
3069 : : * to put a gating node as high in the plan tree as possible.
3070 : : */
8512 tgl@sss.pgh.pa.us 3071 [ + + ]:CBC 466697 : if (bms_is_empty(relids))
3072 : : {
7273 3073 [ + + ]: 9519 : if (ojscope)
3074 : : {
3075 : : /* clause is attached to outer join, eval it there */
6716 3076 : 321 : relids = bms_copy(ojscope);
3077 : : /* mustn't use as gating qual, so don't mark pseudoconstant */
3078 : : }
1216 3079 [ + + ]: 9198 : else if (contain_volatile_functions(clause))
3080 : : {
3081 : : /* eval at original syntactic level */
6716 3082 : 103 : relids = bms_copy(qualscope);
3083 : : /* again, can't mark pseudoconstant */
3084 : : }
3085 : : else
3086 : : {
3087 : : /*
3088 : : * If we are in the top-level join domain, we can push the qual to
3089 : : * the top of the plan tree. Otherwise, be conservative and eval
3090 : : * it at original syntactic level. (Ideally we'd push it to the
3091 : : * top of the current join domain in all cases, but that causes
3092 : : * problems if we later rearrange outer-join evaluation order.
3093 : : * Pseudoconstant quals below the top level are a pretty odd case,
3094 : : * so it's not clear that it's worth working hard on.)
3095 : : */
1193 3096 [ + + ]: 9095 : if (jtitem->jdomain == (JoinDomain *) linitial(root->join_domains))
3097 : 9045 : relids = bms_copy(jtitem->jdomain->jd_relids);
3098 : : else
3099 : 50 : relids = bms_copy(qualscope);
3100 : : /* mark as gating qual */
1216 3101 : 9095 : pseudoconstant = true;
3102 : : /* tell createplan.c to check for gating quals */
3103 : 9095 : root->hasPseudoConstantQuals = true;
3104 : : }
3105 : : }
3106 : :
3107 : : /*----------
3108 : : * Check to see if clause application must be delayed by outer-join
3109 : : * considerations.
3110 : : *
3111 : : * A word about is_pushed_down: we mark the qual as "pushed down" if
3112 : : * it is (potentially) applicable at a level different from its original
3113 : : * syntactic level. This flag is used to distinguish OUTER JOIN ON quals
3114 : : * from other quals pushed down to the same joinrel. The rules are:
3115 : : * WHERE quals and INNER JOIN quals: is_pushed_down = true.
3116 : : * Non-degenerate OUTER JOIN quals: is_pushed_down = false.
3117 : : * Degenerate OUTER JOIN quals: is_pushed_down = true.
3118 : : * A "degenerate" OUTER JOIN qual is one that doesn't mention the
3119 : : * non-nullable side, and hence can be pushed down into the nullable side
3120 : : * without changing the join result. It is correct to treat it as a
3121 : : * regular filter condition at the level where it is evaluated.
3122 : : *
3123 : : * Note: it is not immediately obvious that a simple boolean is enough
3124 : : * for this: if for some reason we were to attach a degenerate qual to
3125 : : * its original join level, it would need to be treated as an outer join
3126 : : * qual there. However, this cannot happen, because all the rels the
3127 : : * clause mentions must be in the outer join's min_righthand, therefore
3128 : : * the join it needs must be formed before the outer join; and we always
3129 : : * attach quals to the lowest level where they can be evaluated. But
3130 : : * if we were ever to re-introduce a mechanism for delaying evaluation
3131 : : * of "expensive" quals, this area would need work.
3132 : : *
3133 : : * Note: generally, use of is_pushed_down has to go through the macro
3134 : : * RINFO_IS_PUSHED_DOWN, because that flag alone is not always sufficient
3135 : : * to tell whether a clause must be treated as pushed-down in context.
3136 : : * This seems like another reason why it should perhaps be rethought.
3137 : : *----------
3138 : : */
2040 3139 [ + + ]: 466697 : if (bms_overlap(relids, outerjoin_nonnullable))
3140 : : {
3141 : : /*
3142 : : * The qual is attached to an outer join and mentions (some of the)
3143 : : * rels on the nonnullable side, so it's not degenerate. If the
3144 : : * caller wants to postpone handling such clauses, just add it to
3145 : : * postponed_oj_qual_list and return. (The work we've done up to here
3146 : : * will have to be redone later, but there's not much of it.)
3147 : : */
1216 3148 [ + + ]: 81752 : if (postponed_oj_qual_list != NULL)
3149 : : {
3150 : 35328 : *postponed_oj_qual_list = lappend(*postponed_oj_qual_list, clause);
3151 : 35328 : return;
3152 : : }
3153 : :
3154 : : /*
3155 : : * We can't use such a clause to deduce equivalence (the left and
3156 : : * right sides might be unequal above the join because one of them has
3157 : : * gone to NULL) ... but we might be able to use it for more limited
3158 : : * deductions, if it is mergejoinable. So consider adding it to the
3159 : : * lists of set-aside outer-join clauses.
3160 : : */
6716 3161 : 46424 : is_pushed_down = false;
7070 3162 : 46424 : maybe_equivalence = false;
6716 3163 : 46424 : maybe_outer_join = true;
3164 : :
3165 : : /*
3166 : : * Now force the qual to be evaluated exactly at the level of joining
3167 : : * corresponding to the outer join. We cannot let it get pushed down
3168 : : * into the nonnullable side, since then we'd produce no output rows,
3169 : : * rather than the intended single null-extended row, for any
3170 : : * nonnullable-side rows failing the qual.
3171 : : */
7466 3172 [ - + ]: 46424 : Assert(ojscope);
3173 : 46424 : relids = ojscope;
7273 3174 [ - + ]: 46424 : Assert(!pseudoconstant);
3175 : : }
3176 : : else
3177 : : {
3178 : : /*
3179 : : * Normal qual clause or degenerate outer-join clause. Either way, we
3180 : : * can mark it as pushed-down.
3181 : : */
7043 3182 : 384945 : is_pushed_down = true;
3183 : :
3184 : : /*
3185 : : * It's possible that this is an IS NULL clause that's redundant with
3186 : : * a lower antijoin; if so we can just discard it. We need not test
3187 : : * in any of the other cases, because this will only be possible for
3188 : : * pushed-down clauses.
3189 : : */
1216 3190 [ + + ]: 384945 : if (check_redundant_nullability_qual(root, clause))
3191 : 986 : return;
3192 : :
3193 : : /* Feed qual to the equivalence machinery, if allowed by caller */
3194 : 383959 : maybe_equivalence = allow_equivalence;
3195 : :
3196 : : /*
3197 : : * Since it doesn't mention the LHS, it's certainly not useful as a
3198 : : * set-aside OJ clause, even if it's in an OJ.
3199 : : */
7637 3200 : 383959 : maybe_outer_join = false;
3201 : : }
3202 : :
3203 : : /*
3204 : : * Build the RestrictInfo node itself.
3205 : : */
1955 3206 : 430383 : restrictinfo = make_restrictinfo(root,
3207 : : (Expr *) clause,
3208 : : is_pushed_down,
3209 : : has_clone,
3210 : : is_clone,
3211 : : pseudoconstant,
3212 : : security_level,
3213 : : relids,
3214 : : incompatible_relids,
3215 : : outerjoin_nonnullable);
3216 : :
3217 : : /*
3218 : : * If it's a join clause, add vars used in the clause to targetlists of
3219 : : * their relations, so that they will be emitted by the plan nodes that
3220 : : * scan those relations (else they won't be available at the join node!).
3221 : : *
3222 : : * Normally we mark the vars as needed at the join identified by "relids".
3223 : : * However, if this is a clone clause then ignore the outer-join relids in
3224 : : * that set. Otherwise, vars appearing in a cloned clause would end up
3225 : : * marked as having to propagate to the highest one of the commuting
3226 : : * joins, which would often be an overestimate. For such clauses, correct
3227 : : * var propagation is ensured by making ojscope include input rels from
3228 : : * both sides of the join.
3229 : : *
3230 : : * See also rebuild_joinclause_attr_needed, which has to partially repeat
3231 : : * this work after removal of an outer join.
3232 : : *
3233 : : * Note: if the clause gets absorbed into an EquivalenceClass then this
3234 : : * may be unnecessary, but for now we have to do it to cover the case
3235 : : * where the EC becomes ec_broken and we end up reinserting the original
3236 : : * clauses into the plan.
3237 : : */
7070 3238 [ + + ]: 430383 : if (bms_membership(relids) == BMS_MULTIPLE)
3239 : : {
5436 3240 : 134366 : List *vars = pull_var_clause(clause,
3241 : : PVC_RECURSE_AGGREGATES |
3242 : : PVC_RECURSE_WINDOWFUNCS |
3243 : : PVC_INCLUDE_PLACEHOLDERS);
3244 : : Relids where_needed;
3245 : :
1216 3246 [ + + ]: 134366 : if (is_clone)
3247 : 3116 : where_needed = bms_intersect(relids, root->all_baserels);
3248 : : else
3249 : 131250 : where_needed = relids;
3250 : 134366 : add_vars_to_targetlist(root, vars, where_needed);
7070 3251 : 134366 : list_free(vars);
3252 : : }
3253 : :
3254 : : /*
3255 : : * We check "mergejoinability" of every clause, not only join clauses,
3256 : : * because we want to know about equivalences between vars of the same
3257 : : * relation, or between vars and consts.
3258 : : */
3259 : 430383 : check_mergejoinable(restrictinfo);
3260 : :
3261 : : /*
3262 : : * If it is a true equivalence clause, send it to the EquivalenceClass
3263 : : * machinery. We do *not* attach it directly to any restriction or join
3264 : : * lists. The EC code will propagate it to the appropriate places later.
3265 : : *
3266 : : * If the clause has a mergejoinable operator, yet isn't an equivalence
3267 : : * because it is an outer-join clause, the EC code may still be able to do
3268 : : * something with it. We add it to appropriate lists for further
3269 : : * consideration later. Specifically:
3270 : : *
3271 : : * If it is a left or right outer-join qualification that relates the two
3272 : : * sides of the outer join (no funny business like leftvar1 = leftvar2 +
3273 : : * rightvar), we add it to root->left_join_clauses or
3274 : : * root->right_join_clauses according to which side the nonnullable
3275 : : * variable appears on.
3276 : : *
3277 : : * If it is a full outer-join qualification, we add it to
3278 : : * root->full_join_clauses. (Ideally we'd discard cases that aren't
3279 : : * leftvar = rightvar, as we do for left/right joins, but this routine
3280 : : * doesn't have the info needed to do that; and the current usage of the
3281 : : * full_join_clauses list doesn't require that, so it's not currently
3282 : : * worth complicating this routine's API to make it possible.)
3283 : : *
3284 : : * If none of the above hold, pass it off to
3285 : : * distribute_restrictinfo_to_rels().
3286 : : *
3287 : : * In all cases, it's important to initialize the left_ec and right_ec
3288 : : * fields of a mergejoinable clause, so that all possibly mergejoinable
3289 : : * expressions have representations in EquivalenceClasses. If
3290 : : * process_equivalence is successful, it will take care of that;
3291 : : * otherwise, we have to call initialize_mergeclause_eclasses to do it.
3292 : : */
3293 [ + + ]: 430383 : if (restrictinfo->mergeopfamilies)
3294 : : {
3295 [ + + ]: 290913 : if (maybe_equivalence)
3296 : : {
1211 3297 [ + + ]: 245846 : if (process_equivalence(root, &restrictinfo, jtitem->jdomain))
7070 3298 : 245629 : return;
3299 : : /* EC rejected it, so set left_ec/right_ec the hard way ... */
3156 3300 [ + + ]: 217 : if (restrictinfo->mergeopfamilies) /* EC might have changed this */
3301 : 172 : initialize_mergeclause_eclasses(root, restrictinfo);
3302 : : /* ... and fall through to distribute_restrictinfo_to_rels */
3303 : : }
7637 3304 [ + - + + ]: 45067 : else if (maybe_outer_join && restrictinfo->can_join)
3305 : : {
3306 : : /* we need to set up left_ec/right_ec the hard way */
5692 3307 : 44529 : initialize_mergeclause_eclasses(root, restrictinfo);
3308 : : /* now see if it should go to any outer-join lists */
1216 3309 [ - + ]: 44529 : Assert(sjinfo != NULL);
7637 3310 [ + + ]: 44529 : if (bms_is_subset(restrictinfo->left_relids,
3311 : 21641 : outerjoin_nonnullable) &&
3312 [ + + ]: 21641 : !bms_overlap(restrictinfo->right_relids,
3313 : : outerjoin_nonnullable))
3314 : : {
3315 : : /* we have outervar = innervar */
1216 3316 : 20596 : OuterJoinClauseInfo *ojcinfo = makeNode(OuterJoinClauseInfo);
3317 : :
3318 : 20596 : ojcinfo->rinfo = restrictinfo;
3319 : 20596 : ojcinfo->sjinfo = sjinfo;
7637 3320 : 20596 : root->left_join_clauses = lappend(root->left_join_clauses,
3321 : : ojcinfo);
7070 3322 : 20596 : return;
3323 : : }
3324 [ + + ]: 23933 : if (bms_is_subset(restrictinfo->right_relids,
6771 bruce@momjian.us 3325 : 23800 : outerjoin_nonnullable) &&
3326 [ + + ]: 23800 : !bms_overlap(restrictinfo->left_relids,
3327 : : outerjoin_nonnullable))
3328 : : {
3329 : : /* we have innervar = outervar */
1216 tgl@sss.pgh.pa.us 3330 : 22755 : OuterJoinClauseInfo *ojcinfo = makeNode(OuterJoinClauseInfo);
3331 : :
3332 : 22755 : ojcinfo->rinfo = restrictinfo;
3333 : 22755 : ojcinfo->sjinfo = sjinfo;
7637 3334 : 22755 : root->right_join_clauses = lappend(root->right_join_clauses,
3335 : : ojcinfo);
7070 3336 : 22755 : return;
3337 : : }
1216 3338 [ + + ]: 1178 : if (sjinfo->jointype == JOIN_FULL)
3339 : : {
3340 : : /* FULL JOIN (above tests cannot match in this case) */
3341 : 1015 : OuterJoinClauseInfo *ojcinfo = makeNode(OuterJoinClauseInfo);
3342 : :
3343 : 1015 : ojcinfo->rinfo = restrictinfo;
3344 : 1015 : ojcinfo->sjinfo = sjinfo;
7637 3345 : 1015 : root->full_join_clauses = lappend(root->full_join_clauses,
3346 : : ojcinfo);
7070 3347 : 1015 : return;
3348 : : }
3349 : : /* nope, so fall through to distribute_restrictinfo_to_rels */
3350 : : }
3351 : : else
3352 : : {
3353 : : /* we still need to set up left_ec/right_ec */
5692 3354 : 538 : initialize_mergeclause_eclasses(root, restrictinfo);
3355 : : }
3356 : : }
3357 : :
3358 : : /* No EC special case applies, so push it into the clause lists */
7070 3359 : 140388 : distribute_restrictinfo_to_rels(root, restrictinfo);
3360 : : }
3361 : :
3362 : : /*
3363 : : * check_redundant_nullability_qual
3364 : : * Check to see if the qual is an IS NULL qual that is redundant with
3365 : : * a lower JOIN_ANTI join.
3366 : : *
3367 : : * We want to suppress redundant IS NULL quals, not so much to save cycles
3368 : : * as to avoid generating bogus selectivity estimates for them. So if
3369 : : * redundancy is detected here, distribute_qual_to_rels() just throws away
3370 : : * the qual.
3371 : : */
3372 : : static bool
6498 3373 : 384945 : check_redundant_nullability_qual(PlannerInfo *root, Node *clause)
3374 : : {
3375 : : Var *forced_null_var;
3376 : : ListCell *lc;
3377 : :
3378 : : /* Check for IS NULL, and identify the Var forced to NULL */
3379 : 384945 : forced_null_var = find_forced_null_var(clause);
3380 [ + + ]: 384945 : if (forced_null_var == NULL)
3381 : 382652 : return false;
3382 : :
3383 : : /*
3384 : : * If the Var comes from the nullable side of a lower antijoin, the IS
3385 : : * NULL condition is necessarily true. If it's not nulled by anything,
3386 : : * there is no point in searching the join_info_list. Otherwise, we need
3387 : : * to find out whether the nulling rel is an antijoin.
3388 : : */
1216 3389 [ + + ]: 2293 : if (forced_null_var->varnullingrels == NULL)
3390 : 1241 : return false;
3391 : :
6498 3392 [ + - + + : 1159 : foreach(lc, root->join_info_list)
+ + ]
3393 : : {
3394 : 1093 : SpecialJoinInfo *sjinfo = (SpecialJoinInfo *) lfirst(lc);
3395 : :
3396 : : /*
3397 : : * This test will not succeed if sjinfo->ojrelid is zero, which is
3398 : : * possible for an antijoin that was converted from a semijoin; but in
3399 : : * such a case the Var couldn't have come from its nullable side.
3400 : : */
1216 3401 [ + + + - : 2079 : if (sjinfo->jointype == JOIN_ANTI && sjinfo->ojrelid != 0 &&
+ - ]
3402 : 986 : bms_is_member(sjinfo->ojrelid, forced_null_var->varnullingrels))
6308 3403 : 986 : return true;
3404 : : }
3405 : :
3406 : 66 : return false;
3407 : : }
3408 : :
3409 : : /*
3410 : : * add_base_clause_to_rel
3411 : : * Add 'restrictinfo' as a baserestrictinfo to the base relation denoted
3412 : : * by 'relid'. We offer some simple prechecks to try to determine if the
3413 : : * qual is always true, in which case we ignore it rather than add it.
3414 : : * If we detect the qual is always false, we replace it with
3415 : : * constant-FALSE.
3416 : : */
3417 : : static void
858 drowley@postgresql.o 3418 : 308413 : add_base_clause_to_rel(PlannerInfo *root, Index relid,
3419 : : RestrictInfo *restrictinfo)
3420 : : {
3421 : 308413 : RelOptInfo *rel = find_base_rel(root, relid);
778 3422 : 308413 : RangeTblEntry *rte = root->simple_rte_array[relid];
3423 : :
858 3424 [ - + ]: 308413 : Assert(bms_membership(restrictinfo->required_relids) == BMS_SINGLETON);
3425 : :
3426 : : /*
3427 : : * For inheritance parent tables, we must always record the RestrictInfo
3428 : : * in baserestrictinfo as is. If we were to transform or skip adding it,
3429 : : * then the original wouldn't be available in apply_child_basequals. Since
3430 : : * there are two RangeTblEntries for inheritance parents, one with
3431 : : * inh==true and the other with inh==false, we're still able to apply this
3432 : : * optimization to the inh==false one. The inh==true one is what
3433 : : * apply_child_basequals() sees, whereas the inh==false one is what's used
3434 : : * for the scan node in the final plan.
3435 : : *
3436 : : * We make an exception to this for partitioned tables. For these, we
3437 : : * always apply the constant-TRUE and constant-FALSE transformations. A
3438 : : * qual which is either of these for a partitioned table must also be that
3439 : : * for all of its child partitions.
3440 : : */
778 3441 [ + + + + ]: 308413 : if (!rte->inh || rte->relkind == RELKIND_PARTITIONED_TABLE)
3442 : : {
3443 : : /* Don't add the clause if it is always true */
3444 [ + + ]: 306692 : if (restriction_is_always_true(root, restrictinfo))
3445 : 352 : return;
3446 : :
3447 : : /*
3448 : : * Substitute the origin qual with constant-FALSE if it is provably
3449 : : * always false.
3450 : : *
3451 : : * Note that we need to keep the same rinfo_serial, since it is in
3452 : : * practice the same condition. We also need to reset the
3453 : : * last_rinfo_serial counter, which is essential to ensure that the
3454 : : * RestrictInfos for the "same" qual condition get identical serial
3455 : : * numbers (see deconstruct_distribute_oj_quals).
3456 : : */
3457 [ - + ]: 306340 : if (restriction_is_always_false(root, restrictinfo))
3458 : : {
778 drowley@postgresql.o 3459 :LBC (21) : int save_rinfo_serial = restrictinfo->rinfo_serial;
568 rguo@postgresql.org 3460 : (21) : int save_last_rinfo_serial = root->last_rinfo_serial;
3461 : :
778 drowley@postgresql.o 3462 : (21) : restrictinfo = make_restrictinfo(root,
3463 : (21) : (Expr *) makeBoolConst(false, false),
3464 : (21) : restrictinfo->is_pushed_down,
3465 : (21) : restrictinfo->has_clone,
3466 : (21) : restrictinfo->is_clone,
3467 : (21) : restrictinfo->pseudoconstant,
3468 : : 0, /* security_level */
3469 : : restrictinfo->required_relids,
3470 : : restrictinfo->incompatible_relids,
3471 : : restrictinfo->outer_relids);
3472 : (21) : restrictinfo->rinfo_serial = save_rinfo_serial;
568 rguo@postgresql.org 3473 : (21) : root->last_rinfo_serial = save_last_rinfo_serial;
3474 : : }
3475 : : }
3476 : :
3477 : : /* Add clause to rel's restriction list */
858 drowley@postgresql.o 3478 :CBC 308061 : rel->baserestrictinfo = lappend(rel->baserestrictinfo, restrictinfo);
3479 : :
3480 : : /* Update security level info */
3481 : 308061 : rel->baserestrict_min_security = Min(rel->baserestrict_min_security,
3482 : : restrictinfo->security_level);
3483 : : }
3484 : :
3485 : : /*
3486 : : * restriction_is_always_true
3487 : : * Check to see if the RestrictInfo is always true.
3488 : : *
3489 : : * Currently we only check for NullTest quals and OR clauses that include
3490 : : * NullTest quals. We may extend it in the future.
3491 : : */
3492 : : bool
3493 : 380106 : restriction_is_always_true(PlannerInfo *root,
3494 : : RestrictInfo *restrictinfo)
3495 : : {
3496 : : /*
3497 : : * For a clone clause, we don't have a reliable way to determine if the
3498 : : * input expression of a NullTest is non-nullable: nullingrel bits in
3499 : : * clone clauses may not reflect reality, so we dare not draw conclusions
3500 : : * from clones about whether Vars are guaranteed not-null.
3501 : : */
452 rguo@postgresql.org 3502 [ + + + + ]: 380106 : if (restrictinfo->has_clone || restrictinfo->is_clone)
3503 : 6212 : return false;
3504 : :
3505 : : /* Check for NullTest qual */
858 drowley@postgresql.o 3506 [ + + ]: 373894 : if (IsA(restrictinfo->clause, NullTest))
3507 : : {
3508 : 7805 : NullTest *nulltest = (NullTest *) restrictinfo->clause;
3509 : :
3510 : : /* is this NullTest an IS_NOT_NULL qual? */
3511 [ + + ]: 7805 : if (nulltest->nulltesttype != IS_NOT_NULL)
3512 : 1731 : return false;
3513 : :
3514 : : /*
3515 : : * Empty rows can appear NULL in some contexts and NOT NULL in others,
3516 : : * so avoid this optimization for row expressions.
3517 : : */
418 bruce@momjian.us 3518 [ + + ]: 6074 : if (nulltest->argisrow)
3519 : 118 : return false;
3520 : :
79 rguo@postgresql.org 3521 :GNC 5956 : return expr_is_nonnullable(root, nulltest->arg, NOTNULL_SOURCE_RELOPT);
3522 : : }
3523 : :
3524 : : /* If it's an OR, check its sub-clauses */
858 drowley@postgresql.o 3525 [ + + ]:CBC 366089 : if (restriction_is_or_clause(restrictinfo))
3526 : : {
3527 : : ListCell *lc;
3528 : :
3529 [ - + ]: 7531 : Assert(is_orclause(restrictinfo->orclause));
3530 : :
3531 : : /*
3532 : : * if any of the given OR branches is provably always true then the
3533 : : * entire condition is true.
3534 : : */
3535 [ + - + + : 24970 : foreach(lc, ((BoolExpr *) restrictinfo->orclause)->args)
+ + ]
3536 : : {
3537 : 17439 : Node *orarg = (Node *) lfirst(lc);
3538 : :
3539 [ + + ]: 17439 : if (!IsA(orarg, RestrictInfo))
3540 : 1466 : continue;
3541 : :
3542 [ - + ]: 15973 : if (restriction_is_always_true(root, (RestrictInfo *) orarg))
858 drowley@postgresql.o 3543 :LBC (6) : return true;
3544 : : }
3545 : : }
3546 : :
858 drowley@postgresql.o 3547 :CBC 366089 : return false;
3548 : : }
3549 : :
3550 : : /*
3551 : : * restriction_is_always_false
3552 : : * Check to see if the RestrictInfo is always false.
3553 : : *
3554 : : * Currently we only check for NullTest quals and OR clauses that include
3555 : : * NullTest quals. We may extend it in the future.
3556 : : */
3557 : : bool
3558 : 370671 : restriction_is_always_false(PlannerInfo *root,
3559 : : RestrictInfo *restrictinfo)
3560 : : {
3561 : : /*
3562 : : * For a clone clause, we don't have a reliable way to determine if the
3563 : : * input expression of a NullTest is non-nullable: nullingrel bits in
3564 : : * clone clauses may not reflect reality, so we dare not draw conclusions
3565 : : * from clones about whether Vars are guaranteed not-null.
3566 : : */
452 rguo@postgresql.org 3567 [ + + + + ]: 370671 : if (restrictinfo->has_clone || restrictinfo->is_clone)
3568 : 6212 : return false;
3569 : :
3570 : : /* Check for NullTest qual */
858 drowley@postgresql.o 3571 [ + + ]: 364459 : if (IsA(restrictinfo->clause, NullTest))
3572 : : {
3573 : 6777 : NullTest *nulltest = (NullTest *) restrictinfo->clause;
3574 : :
3575 : : /* is this NullTest an IS_NULL qual? */
3576 [ + + ]: 6777 : if (nulltest->nulltesttype != IS_NULL)
3577 : 5249 : return false;
3578 : :
3579 : : /*
3580 : : * Empty rows can appear NULL in some contexts and NOT NULL in others,
3581 : : * so avoid this optimization for row expressions.
3582 : : */
418 bruce@momjian.us 3583 [ + + ]: 1528 : if (nulltest->argisrow)
3584 : 88 : return false;
3585 : :
79 rguo@postgresql.org 3586 :GNC 1440 : return expr_is_nonnullable(root, nulltest->arg, NOTNULL_SOURCE_RELOPT);
3587 : : }
3588 : :
3589 : : /* If it's an OR, check its sub-clauses */
858 drowley@postgresql.o 3590 [ + + ]:CBC 357682 : if (restriction_is_or_clause(restrictinfo))
3591 : : {
3592 : : ListCell *lc;
3593 : :
3594 [ - + ]: 7531 : Assert(is_orclause(restrictinfo->orclause));
3595 : :
3596 : : /*
3597 : : * Currently, when processing OR expressions, we only return true when
3598 : : * all of the OR branches are always false. This could perhaps be
3599 : : * expanded to remove OR branches that are provably false. This may
3600 : : * be a useful thing to do as it could result in the OR being left
3601 : : * with a single arg. That's useful as it would allow the OR
3602 : : * condition to be replaced with its single argument which may allow
3603 : : * use of an index for faster filtering on the remaining condition.
3604 : : */
3605 [ + - + - : 7531 : foreach(lc, ((BoolExpr *) restrictinfo->orclause)->args)
+ - ]
3606 : : {
3607 : 7531 : Node *orarg = (Node *) lfirst(lc);
3608 : :
3609 [ + + ]: 7531 : if (!IsA(orarg, RestrictInfo) ||
3610 [ + - ]: 6890 : !restriction_is_always_false(root, (RestrictInfo *) orarg))
3611 : 7531 : return false;
3612 : : }
858 drowley@postgresql.o 3613 :LBC (6) : return true;
3614 : : }
3615 : :
858 drowley@postgresql.o 3616 :CBC 350151 : return false;
3617 : : }
3618 : :
3619 : : /*
3620 : : * distribute_restrictinfo_to_rels
3621 : : * Push a completed RestrictInfo into the proper restriction or join
3622 : : * clause list(s).
3623 : : *
3624 : : * This is the last step of distribute_qual_to_rels() for ordinary qual
3625 : : * clauses. Clauses that are interesting for equivalence-class processing
3626 : : * are diverted to the EC machinery, but may ultimately get fed back here.
3627 : : */
3628 : : void
7070 tgl@sss.pgh.pa.us 3629 : 365854 : distribute_restrictinfo_to_rels(PlannerInfo *root,
3630 : : RestrictInfo *restrictinfo)
3631 : : {
3632 : 365854 : Relids relids = restrictinfo->required_relids;
3633 : :
914 drowley@postgresql.o 3634 [ + - ]: 365854 : if (!bms_is_empty(relids))
3635 : : {
3636 : : int relid;
3637 : :
3638 [ + + ]: 365854 : if (bms_get_singleton_member(relids, &relid))
3639 : : {
3640 : : /*
3641 : : * There is only one relation participating in the clause, so it
3642 : : * is a restriction clause for that relation.
3643 : : */
858 3644 : 308413 : add_base_clause_to_rel(root, relid, restrictinfo);
3645 : : }
3646 : : else
3647 : : {
3648 : : /*
3649 : : * The clause is a join clause, since there is more than one rel
3650 : : * in its relid set.
3651 : : */
3652 : :
3653 : : /*
3654 : : * Check for hashjoinable operators. (We don't bother setting the
3655 : : * hashjoin info except in true join clauses.)
3656 : : */
5630 tgl@sss.pgh.pa.us 3657 : 57441 : check_hashjoinable(restrictinfo);
3658 : :
3659 : : /*
3660 : : * Likewise, check if the clause is suitable to be used with a
3661 : : * Memoize node to cache inner tuples during a parameterized
3662 : : * nested loop.
3663 : : */
1781 drowley@postgresql.o 3664 : 57441 : check_memoizable(restrictinfo);
3665 : :
3666 : : /*
3667 : : * Add clause to the join lists of all the relevant relations.
3668 : : */
7070 tgl@sss.pgh.pa.us 3669 : 57441 : add_join_clause_to_rels(root, restrictinfo, relids);
3670 : : }
3671 : : }
3672 : : else
3673 : : {
3674 : : /*
3675 : : * clause references no rels, and therefore we have no place to attach
3676 : : * it. Shouldn't get here if callers are working properly.
3677 : : */
914 drowley@postgresql.o 3678 [ # # ]:UBC 0 : elog(ERROR, "cannot cope with variable-free clause");
3679 : : }
7070 tgl@sss.pgh.pa.us 3680 :CBC 365854 : }
3681 : :
3682 : : /*
3683 : : * process_implied_equality
3684 : : * Create a restrictinfo item that says "item1 op item2", and push it
3685 : : * into the appropriate lists. (In practice opno is always a btree
3686 : : * equality operator.)
3687 : : *
3688 : : * "qualscope" is the nominal syntactic level to impute to the restrictinfo.
3689 : : * This must contain at least all the rels used in the expressions, but it
3690 : : * is used only to set the qual application level when both exprs are
3691 : : * variable-free. (Hence, it should usually match the join domain in which
3692 : : * the clause applies.) Otherwise the qual is applied at the lowest join
3693 : : * level that provides all its variables.
3694 : : *
3695 : : * "security_level" is the security level to assign to the new restrictinfo.
3696 : : *
3697 : : * "both_const" indicates whether both items are known pseudo-constant;
3698 : : * in this case it is worth applying eval_const_expressions() in case we
3699 : : * can produce constant TRUE or constant FALSE. (Otherwise it's not,
3700 : : * because the expressions went through eval_const_expressions already.)
3701 : : *
3702 : : * Returns the generated RestrictInfo, if any. The result will be NULL
3703 : : * if both_const is true and we successfully reduced the clause to
3704 : : * constant TRUE.
3705 : : *
3706 : : * Note: this function will copy item1 and item2, but it is caller's
3707 : : * responsibility to make sure that the Relids parameters are fresh copies
3708 : : * not shared with other uses.
3709 : : *
3710 : : * Note: we do not do initialize_mergeclause_eclasses() here. It is
3711 : : * caller's responsibility that left_ec/right_ec be set as necessary.
3712 : : */
3713 : : RestrictInfo *
3714 : 25086 : process_implied_equality(PlannerInfo *root,
3715 : : Oid opno,
3716 : : Oid collation,
3717 : : Expr *item1,
3718 : : Expr *item2,
3719 : : Relids qualscope,
3720 : : Index security_level,
3721 : : bool both_const)
3722 : : {
3723 : : RestrictInfo *restrictinfo;
3724 : : Node *clause;
3725 : : Relids relids;
2040 3726 : 25086 : bool pseudoconstant = false;
3727 : :
3728 : : /*
3729 : : * Build the new clause. Copy to ensure it shares no substructure with
3730 : : * original (this is necessary in case there are subselects in there...)
3731 : : */
3732 : 25086 : clause = (Node *) make_opclause(opno,
3733 : : BOOLOID, /* opresulttype */
3734 : : false, /* opretset */
3735 : 25086 : copyObject(item1),
3736 : 25086 : copyObject(item2),
3737 : : InvalidOid,
3738 : : collation);
3739 : :
3740 : : /* If both constant, try to reduce to a boolean constant. */
7070 3741 [ + + ]: 25086 : if (both_const)
3742 : : {
2040 3743 : 110 : clause = eval_const_expressions(root, clause);
3744 : :
3745 : : /* If we produced const TRUE, just drop the clause */
7070 3746 [ + - + + ]: 110 : if (clause && IsA(clause, Const))
3747 : : {
6771 bruce@momjian.us 3748 : 105 : Const *cclause = (Const *) clause;
3749 : :
7070 tgl@sss.pgh.pa.us 3750 [ - + ]: 105 : Assert(cclause->consttype == BOOLOID);
3751 [ + - - + ]: 105 : if (!cclause->constisnull && DatumGetBool(cclause->constvalue))
2040 tgl@sss.pgh.pa.us 3752 :UBC 0 : return NULL;
3753 : : }
3754 : : }
3755 : :
3756 : : /*
3757 : : * The rest of this is a very cut-down version of distribute_qual_to_rels.
3758 : : * We can skip most of the work therein, but there are a couple of special
3759 : : * cases we still have to handle.
3760 : : *
3761 : : * Retrieve all relids mentioned within the possibly-simplified clause.
3762 : : */
1955 tgl@sss.pgh.pa.us 3763 :CBC 25086 : relids = pull_varnos(root, clause);
2040 3764 [ - + ]: 25086 : Assert(bms_is_subset(relids, qualscope));
3765 : :
3766 : : /*
3767 : : * If the clause is variable-free, our normal heuristic for pushing it
3768 : : * down to just the mentioned rels doesn't work, because there are none.
3769 : : * Apply it as a gating qual at the appropriate level (see comments for
3770 : : * get_join_domain_min_rels).
3771 : : */
3772 [ + + ]: 25086 : if (bms_is_empty(relids))
3773 : : {
3774 : : /* eval at join domain's safe level */
1193 3775 : 110 : relids = get_join_domain_min_rels(root, qualscope);
3776 : : /* mark as gating qual */
1216 3777 : 110 : pseudoconstant = true;
3778 : : /* tell createplan.c to check for gating quals */
3779 : 110 : root->hasPseudoConstantQuals = true;
3780 : : }
3781 : :
3782 : : /*
3783 : : * Build the RestrictInfo node itself.
3784 : : */
1955 3785 : 25086 : restrictinfo = make_restrictinfo(root,
3786 : : (Expr *) clause,
3787 : : true, /* is_pushed_down */
3788 : : false, /* !has_clone */
3789 : : false, /* !is_clone */
3790 : : pseudoconstant,
3791 : : security_level,
3792 : : relids,
3793 : : NULL, /* incompatible_relids */
3794 : : NULL); /* outer_relids */
3795 : :
3796 : : /*
3797 : : * If it's a join clause, add vars used in the clause to targetlists of
3798 : : * their relations, so that they will be emitted by the plan nodes that
3799 : : * scan those relations (else they won't be available at the join node!).
3800 : : *
3801 : : * Typically, we'd have already done this when the component expressions
3802 : : * were first seen by distribute_qual_to_rels; but it is possible that
3803 : : * some of the Vars could have missed having that done because they only
3804 : : * appeared in single-relation clauses originally. So do it here for
3805 : : * safety.
3806 : : *
3807 : : * See also rebuild_joinclause_attr_needed, which has to partially repeat
3808 : : * this work after removal of an outer join. (Since we will put this
3809 : : * clause into the joininfo lists, that function needn't do any extra work
3810 : : * to find it.)
3811 : : */
2040 3812 [ + + ]: 25086 : if (bms_membership(relids) == BMS_MULTIPLE)
3813 : : {
3814 : 50 : List *vars = pull_var_clause(clause,
3815 : : PVC_RECURSE_AGGREGATES |
3816 : : PVC_RECURSE_WINDOWFUNCS |
3817 : : PVC_INCLUDE_PLACEHOLDERS);
3818 : :
1382 3819 : 50 : add_vars_to_targetlist(root, vars, relids);
2040 3820 : 50 : list_free(vars);
3821 : : }
3822 : :
3823 : : /*
3824 : : * Check mergejoinability. This will usually succeed, since the op came
3825 : : * from an EquivalenceClass; but we could have reduced the original clause
3826 : : * to a constant.
3827 : : */
3828 : 25086 : check_mergejoinable(restrictinfo);
3829 : :
3830 : : /*
3831 : : * Note we don't do initialize_mergeclause_eclasses(); the caller can
3832 : : * handle that much more cheaply than we can. It's okay to call
3833 : : * distribute_restrictinfo_to_rels() before that happens.
3834 : : */
3835 : :
3836 : : /*
3837 : : * Push the new clause into all the appropriate restrictinfo lists.
3838 : : */
3839 : 25086 : distribute_restrictinfo_to_rels(root, restrictinfo);
3840 : :
3841 : 25086 : return restrictinfo;
3842 : : }
3843 : :
3844 : : /*
3845 : : * build_implied_join_equality --- build a RestrictInfo for a derived equality
3846 : : *
3847 : : * This overlaps the functionality of process_implied_equality(), but we
3848 : : * must not push the RestrictInfo into the joininfo tree.
3849 : : *
3850 : : * Note: this function will copy item1 and item2, but it is caller's
3851 : : * responsibility to make sure that the Relids parameters are fresh copies
3852 : : * not shared with other uses.
3853 : : *
3854 : : * Note: we do not do initialize_mergeclause_eclasses() here. It is
3855 : : * caller's responsibility that left_ec/right_ec be set as necessary.
3856 : : */
3857 : : RestrictInfo *
1955 3858 : 74380 : build_implied_join_equality(PlannerInfo *root,
3859 : : Oid opno,
3860 : : Oid collation,
3861 : : Expr *item1,
3862 : : Expr *item2,
3863 : : Relids qualscope,
3864 : : Index security_level)
3865 : : {
3866 : : RestrictInfo *restrictinfo;
3867 : : Expr *clause;
3868 : :
3869 : : /*
3870 : : * Build the new clause. Copy to ensure it shares no substructure with
3871 : : * original (this is necessary in case there are subselects in there...)
3872 : : */
7070 3873 : 74380 : clause = make_opclause(opno,
3874 : : BOOLOID, /* opresulttype */
3875 : : false, /* opretset */
3369 peter_e@gmx.net 3876 : 74380 : copyObject(item1),
3877 : 74380 : copyObject(item2),
3878 : : InvalidOid,
3879 : : collation);
3880 : :
3881 : : /*
3882 : : * Build the RestrictInfo node itself.
3883 : : */
1955 tgl@sss.pgh.pa.us 3884 : 74380 : restrictinfo = make_restrictinfo(root,
3885 : : clause,
3886 : : true, /* is_pushed_down */
3887 : : false, /* !has_clone */
3888 : : false, /* !is_clone */
3889 : : false, /* pseudoconstant */
3890 : : security_level, /* security_level */
3891 : : qualscope, /* required_relids */
3892 : : NULL, /* incompatible_relids */
3893 : : NULL); /* outer_relids */
3894 : :
3895 : : /* Set mergejoinability/hashjoinability flags */
7070 3896 : 74380 : check_mergejoinable(restrictinfo);
5630 3897 : 74380 : check_hashjoinable(restrictinfo);
1781 drowley@postgresql.o 3898 : 74380 : check_memoizable(restrictinfo);
3899 : :
7070 tgl@sss.pgh.pa.us 3900 : 74380 : return restrictinfo;
3901 : : }
3902 : :
3903 : : /*
3904 : : * get_join_domain_min_rels
3905 : : * Identify the appropriate join level for derived quals belonging
3906 : : * to the join domain with the given relids.
3907 : : *
3908 : : * When we derive a pseudoconstant (Var-free) clause from an EquivalenceClass,
3909 : : * we'd ideally apply the clause at the top level of the EC's join domain.
3910 : : * However, if there are any outer joins inside that domain that get commuted
3911 : : * with joins outside it, that leads to not finding a correct place to apply
3912 : : * the clause. Instead, remove any lower outer joins from the relid set,
3913 : : * and apply the clause to just the remaining rels. This still results in a
3914 : : * correct answer, since if the clause produces FALSE then the LHS of these
3915 : : * joins will be empty leading to an empty join result.
3916 : : *
3917 : : * However, there's no need to remove outer joins if this is the top-level
3918 : : * join domain of the query, since then there's nothing else to commute with.
3919 : : *
3920 : : * Note: it's tempting to use this in distribute_qual_to_rels where it's
3921 : : * dealing with pseudoconstant quals; but we can't because the necessary
3922 : : * SpecialJoinInfos aren't all formed at that point.
3923 : : *
3924 : : * The result is always freshly palloc'd; we do not modify domain_relids.
3925 : : */
3926 : : static Relids
1193 3927 : 110 : get_join_domain_min_rels(PlannerInfo *root, Relids domain_relids)
3928 : : {
3929 : 110 : Relids result = bms_copy(domain_relids);
3930 : : ListCell *lc;
3931 : :
3932 : : /* Top-level join domain? */
3933 [ + + ]: 110 : if (bms_equal(result, root->all_query_rels))
3934 : 55 : return result;
3935 : :
3936 : : /* Nope, look for lower outer joins that could potentially commute out */
3937 [ + - + + : 115 : foreach(lc, root->join_info_list)
+ + ]
3938 : : {
3939 : 60 : SpecialJoinInfo *sjinfo = (SpecialJoinInfo *) lfirst(lc);
3940 : :
3941 [ + - + + ]: 120 : if (sjinfo->jointype == JOIN_LEFT &&
3942 : 60 : bms_is_member(sjinfo->ojrelid, result))
3943 : : {
3944 : 5 : result = bms_del_member(result, sjinfo->ojrelid);
3945 : 5 : result = bms_del_members(result, sjinfo->syn_righthand);
3946 : : }
3947 : : }
3948 : 55 : return result;
3949 : : }
3950 : :
3951 : :
3952 : : /*
3953 : : * rebuild_joinclause_attr_needed
3954 : : * Put back attr_needed bits for Vars/PHVs needed for join clauses.
3955 : : *
3956 : : * This is used to rebuild attr_needed/ph_needed sets after removal of a
3957 : : * useless outer join. It should match what distribute_qual_to_rels did,
3958 : : * except that we call add_vars_to_attr_needed not add_vars_to_targetlist.
3959 : : */
3960 : : void
610 3961 : 9177 : rebuild_joinclause_attr_needed(PlannerInfo *root)
3962 : : {
3963 : : /*
3964 : : * We must examine all join clauses, but there's no value in processing
3965 : : * any join clause more than once. So it's slightly annoying that we have
3966 : : * to find them via the per-base-relation joininfo lists. Avoid duplicate
3967 : : * processing by tracking the rinfo_serial numbers of join clauses we've
3968 : : * already seen. (This doesn't work for is_clone clauses, so we must
3969 : : * waste effort on them.)
3970 : : */
3971 : 9177 : Bitmapset *seen_serials = NULL;
3972 : : Index rti;
3973 : :
3974 : : /* Scan all baserels for join clauses */
3975 [ + + ]: 60567 : for (rti = 1; rti < root->simple_rel_array_size; rti++)
3976 : : {
3977 : 51390 : RelOptInfo *brel = root->simple_rel_array[rti];
3978 : : ListCell *lc;
3979 : :
3980 [ + + ]: 51390 : if (brel == NULL)
3981 : 34173 : continue;
3982 [ - + ]: 17217 : if (brel->reloptkind != RELOPT_BASEREL)
610 tgl@sss.pgh.pa.us 3983 :UBC 0 : continue;
3984 : :
610 tgl@sss.pgh.pa.us 3985 [ + + + + :CBC 25846 : foreach(lc, brel->joininfo)
+ + ]
3986 : : {
3987 : 8629 : RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
3988 : 8629 : Relids relids = rinfo->required_relids;
3989 : :
3990 [ + + ]: 8629 : if (!rinfo->is_clone) /* else serial number is not unique */
3991 : : {
3992 [ + + ]: 8559 : if (bms_is_member(rinfo->rinfo_serial, seen_serials))
3993 : 4583 : continue; /* saw it already */
3994 : 3976 : seen_serials = bms_add_member(seen_serials,
3995 : : rinfo->rinfo_serial);
3996 : : }
3997 : :
3998 [ + - ]: 4046 : if (bms_membership(relids) == BMS_MULTIPLE)
3999 : : {
4000 : 4046 : List *vars = pull_var_clause((Node *) rinfo->clause,
4001 : : PVC_RECURSE_AGGREGATES |
4002 : : PVC_RECURSE_WINDOWFUNCS |
4003 : : PVC_INCLUDE_PLACEHOLDERS);
4004 : : Relids where_needed;
4005 : :
4006 [ + + ]: 4046 : if (rinfo->is_clone)
4007 : 70 : where_needed = bms_intersect(relids, root->all_baserels);
4008 : : else
4009 : 3976 : where_needed = relids;
4010 : 4046 : add_vars_to_attr_needed(root, vars, where_needed);
4011 : 4046 : list_free(vars);
4012 : : }
4013 : : }
4014 : : }
4015 : 9177 : }
4016 : :
4017 : :
4018 : : /*
4019 : : * match_foreign_keys_to_quals
4020 : : * Match foreign-key constraints to equivalence classes and join quals
4021 : : *
4022 : : * The idea here is to see which query join conditions match equality
4023 : : * constraints of a foreign-key relationship. For such join conditions,
4024 : : * we can use the FK semantics to make selectivity estimates that are more
4025 : : * reliable than estimating from statistics, especially for multiple-column
4026 : : * FKs, where the normal assumption of independent conditions tends to fail.
4027 : : *
4028 : : * In this function we annotate the ForeignKeyOptInfos in root->fkey_list
4029 : : * with info about which eclasses and join qual clauses they match, and
4030 : : * discard any ForeignKeyOptInfos that are irrelevant for the query.
4031 : : */
4032 : : void
3633 4033 : 255472 : match_foreign_keys_to_quals(PlannerInfo *root)
4034 : : {
4035 : 255472 : List *newlist = NIL;
4036 : : ListCell *lc;
4037 : :
4038 [ + + + + : 257190 : foreach(lc, root->fkey_list)
+ + ]
4039 : : {
4040 : 1718 : ForeignKeyOptInfo *fkinfo = (ForeignKeyOptInfo *) lfirst(lc);
4041 : : RelOptInfo *con_rel;
4042 : : RelOptInfo *ref_rel;
4043 : : int colno;
4044 : :
4045 : : /*
4046 : : * Either relid might identify a rel that is in the query's rtable but
4047 : : * isn't referenced by the jointree, or has been removed by join
4048 : : * removal, so that it won't have a RelOptInfo. Hence don't use
4049 : : * find_base_rel() here. We can ignore such FKs.
4050 : : */
3622 4051 [ + - ]: 1718 : if (fkinfo->con_relid >= root->simple_rel_array_size ||
4052 [ - + ]: 1718 : fkinfo->ref_relid >= root->simple_rel_array_size)
3622 tgl@sss.pgh.pa.us 4053 :UBC 0 : continue; /* just paranoia */
3622 tgl@sss.pgh.pa.us 4054 :CBC 1718 : con_rel = root->simple_rel_array[fkinfo->con_relid];
4055 [ + + ]: 1718 : if (con_rel == NULL)
4056 : 10 : continue;
4057 : 1708 : ref_rel = root->simple_rel_array[fkinfo->ref_relid];
4058 [ + + ]: 1708 : if (ref_rel == NULL)
4059 : 20 : continue;
4060 : :
4061 : : /*
4062 : : * Ignore FK unless both rels are baserels. This gets rid of FKs that
4063 : : * link to inheritance child rels (otherrels).
4064 : : */
3633 4065 [ + - ]: 1688 : if (con_rel->reloptkind != RELOPT_BASEREL ||
4066 [ - + ]: 1688 : ref_rel->reloptkind != RELOPT_BASEREL)
3633 tgl@sss.pgh.pa.us 4067 :UBC 0 : continue;
4068 : :
4069 : : /*
4070 : : * Scan the columns and try to match them to eclasses and quals.
4071 : : *
4072 : : * Note: for simple inner joins, any match should be in an eclass.
4073 : : * "Loose" quals that syntactically match an FK equality must have
4074 : : * been rejected for EC status because they are outer-join quals or
4075 : : * similar. We can still consider them to match the FK.
4076 : : */
3633 tgl@sss.pgh.pa.us 4077 [ + + ]:CBC 3826 : for (colno = 0; colno < fkinfo->nkeys; colno++)
4078 : : {
4079 : : EquivalenceClass *ec;
4080 : : AttrNumber con_attno,
4081 : : ref_attno;
4082 : : Oid fpeqop;
4083 : : ListCell *lc2;
4084 : :
2040 4085 : 2138 : ec = match_eclasses_to_foreign_key_col(root, fkinfo, colno);
4086 : : /* Don't bother looking for loose quals if we got an EC match */
4087 [ + + ]: 2138 : if (ec != NULL)
4088 : : {
3633 4089 : 525 : fkinfo->nmatched_ec++;
2040 4090 [ + + ]: 525 : if (ec->ec_has_const)
4091 : 45 : fkinfo->nconst_ec++;
3633 4092 : 525 : continue;
4093 : : }
4094 : :
4095 : : /*
4096 : : * Scan joininfo list for relevant clauses. Either rel's joininfo
4097 : : * list would do equally well; we use con_rel's.
4098 : : */
4099 : 1613 : con_attno = fkinfo->conkey[colno];
4100 : 1613 : ref_attno = fkinfo->confkey[colno];
4101 : 1613 : fpeqop = InvalidOid; /* we'll look this up only if needed */
4102 : :
4103 [ + + + + : 4203 : foreach(lc2, con_rel->joininfo)
+ + ]
4104 : : {
4105 : 2590 : RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc2);
4106 : 2590 : OpExpr *clause = (OpExpr *) rinfo->clause;
4107 : : Var *leftvar;
4108 : : Var *rightvar;
4109 : :
4110 : : /* Only binary OpExprs are useful for consideration */
4111 [ + + - + ]: 5168 : if (!IsA(clause, OpExpr) ||
4112 : 2578 : list_length(clause->args) != 2)
3633 tgl@sss.pgh.pa.us 4113 :GBC 12 : continue;
3633 tgl@sss.pgh.pa.us 4114 :CBC 2578 : leftvar = (Var *) get_leftop((Expr *) clause);
4115 : 2578 : rightvar = (Var *) get_rightop((Expr *) clause);
4116 : :
4117 : : /* Operands must be Vars, possibly with RelabelType */
4118 [ + - + + ]: 2783 : while (leftvar && IsA(leftvar, RelabelType))
4119 : 205 : leftvar = (Var *) ((RelabelType *) leftvar)->arg;
4120 [ + - + + ]: 2578 : if (!(leftvar && IsA(leftvar, Var)))
3633 tgl@sss.pgh.pa.us 4121 :GBC 12 : continue;
3633 tgl@sss.pgh.pa.us 4122 [ + - + + ]:CBC 2756 : while (rightvar && IsA(rightvar, RelabelType))
4123 : 190 : rightvar = (Var *) ((RelabelType *) rightvar)->arg;
4124 [ + - + + ]: 2566 : if (!(rightvar && IsA(rightvar, Var)))
4125 : 25 : continue;
4126 : :
4127 : : /* Now try to match the vars to the current foreign key cols */
4128 [ + + ]: 2541 : if (fkinfo->ref_relid == leftvar->varno &&
4129 [ + + ]: 2436 : ref_attno == leftvar->varattno &&
4130 [ + - ]: 1391 : fkinfo->con_relid == rightvar->varno &&
4131 [ + + ]: 1391 : con_attno == rightvar->varattno)
4132 : : {
4133 : : /* Vars match, but is it the right operator? */
4134 [ + - ]: 1326 : if (clause->opno == fkinfo->conpfeqop[colno])
4135 : : {
4136 : 1326 : fkinfo->rinfos[colno] = lappend(fkinfo->rinfos[colno],
4137 : : rinfo);
4138 : 1326 : fkinfo->nmatched_ri++;
4139 : : }
4140 : : }
4141 [ + + ]: 1215 : else if (fkinfo->ref_relid == rightvar->varno &&
4142 [ + + ]: 75 : ref_attno == rightvar->varattno &&
4143 [ + - ]: 30 : fkinfo->con_relid == leftvar->varno &&
4144 [ + - ]: 30 : con_attno == leftvar->varattno)
4145 : : {
4146 : : /*
4147 : : * Reverse match, must check commutator operator. Look it
4148 : : * up if we didn't already. (In the worst case we might
4149 : : * do multiple lookups here, but that would require an FK
4150 : : * equality operator without commutator, which is
4151 : : * unlikely.)
4152 : : */
4153 [ + - ]: 30 : if (!OidIsValid(fpeqop))
4154 : 30 : fpeqop = get_commutator(fkinfo->conpfeqop[colno]);
4155 [ + - ]: 30 : if (clause->opno == fpeqop)
4156 : : {
4157 : 30 : fkinfo->rinfos[colno] = lappend(fkinfo->rinfos[colno],
4158 : : rinfo);
4159 : 30 : fkinfo->nmatched_ri++;
4160 : : }
4161 : : }
4162 : : }
4163 : : /* If we found any matching loose quals, count col as matched */
4164 [ + + ]: 1613 : if (fkinfo->rinfos[colno])
4165 : 1356 : fkinfo->nmatched_rcols++;
4166 : : }
4167 : :
4168 : : /*
4169 : : * Currently, we drop multicolumn FKs that aren't fully matched to the
4170 : : * query. Later we might figure out how to derive some sort of
4171 : : * estimate from them, in which case this test should be weakened to
4172 : : * "if ((fkinfo->nmatched_ec + fkinfo->nmatched_rcols) > 0)".
4173 : : */
4174 [ + + ]: 1688 : if ((fkinfo->nmatched_ec + fkinfo->nmatched_rcols) == fkinfo->nkeys)
4175 : 1451 : newlist = lappend(newlist, fkinfo);
4176 : : }
4177 : : /* Replace fkey_list, thereby discarding any useless entries */
4178 : 255472 : root->fkey_list = newlist;
4179 : 255472 : }
4180 : :
4181 : :
4182 : : /*****************************************************************************
4183 : : *
4184 : : * CHECKS FOR MERGEJOINABLE AND HASHJOINABLE CLAUSES
4185 : : *
4186 : : *****************************************************************************/
4187 : :
4188 : : /*
4189 : : * check_mergejoinable
4190 : : * If the restrictinfo's clause is mergejoinable, set the mergejoin
4191 : : * info fields in the restrictinfo.
4192 : : *
4193 : : * Currently, we support mergejoin for binary opclauses where
4194 : : * the operator is a mergejoinable operator. The arguments can be
4195 : : * anything --- as long as there are no volatile functions in them.
4196 : : */
4197 : : static void
9784 4198 : 529849 : check_mergejoinable(RestrictInfo *restrictinfo)
4199 : : {
4200 : 529849 : Expr *clause = restrictinfo->clause;
4201 : : Oid opno;
4202 : : Node *leftarg;
4203 : :
7273 4204 [ + + ]: 529849 : if (restrictinfo->pseudoconstant)
4205 : 9205 : return;
8570 4206 [ + + ]: 520644 : if (!is_opclause(clause))
9784 4207 : 67273 : return;
8035 neilc@samurai.com 4208 [ + + ]: 453371 : if (list_length(((OpExpr *) clause)->args) != 2)
9784 tgl@sss.pgh.pa.us 4209 : 20 : return;
4210 : :
8570 4211 : 453351 : opno = ((OpExpr *) clause)->opno;
5691 4212 : 453351 : leftarg = linitial(((OpExpr *) clause)->args);
4213 : :
4214 [ + + ]: 453351 : if (op_mergejoinable(opno, exprType(leftarg)) &&
1888 drowley@postgresql.o 4215 [ + + ]: 390295 : !contain_volatile_functions((Node *) restrictinfo))
7070 tgl@sss.pgh.pa.us 4216 : 390269 : restrictinfo->mergeopfamilies = get_mergejoin_opfamilies(opno);
4217 : :
4218 : : /*
4219 : : * Note: op_mergejoinable is just a hint; if we fail to find the operator
4220 : : * in any btree opfamilies, mergeopfamilies remains NIL and so the clause
4221 : : * is not treated as mergejoinable.
4222 : : */
4223 : : }
4224 : :
4225 : : /*
4226 : : * check_hashjoinable
4227 : : * If the restrictinfo's clause is hashjoinable, set the hashjoin
4228 : : * info fields in the restrictinfo.
4229 : : *
4230 : : * Currently, we support hashjoin for binary opclauses where
4231 : : * the operator is a hashjoinable operator. The arguments can be
4232 : : * anything --- as long as there are no volatile functions in them.
4233 : : */
4234 : : static void
9784 4235 : 131821 : check_hashjoinable(RestrictInfo *restrictinfo)
4236 : : {
4237 : 131821 : Expr *clause = restrictinfo->clause;
4238 : : Oid opno;
4239 : : Node *leftarg;
4240 : :
7273 4241 [ + + ]: 131821 : if (restrictinfo->pseudoconstant)
4242 : 5504 : return;
8570 4243 [ + + ]: 126317 : if (!is_opclause(clause))
9784 4244 : 5773 : return;
8035 neilc@samurai.com 4245 [ - + ]: 120544 : if (list_length(((OpExpr *) clause)->args) != 2)
9784 tgl@sss.pgh.pa.us 4246 :UBC 0 : return;
4247 : :
8570 tgl@sss.pgh.pa.us 4248 :CBC 120544 : opno = ((OpExpr *) clause)->opno;
5691 4249 : 120544 : leftarg = linitial(((OpExpr *) clause)->args);
4250 : :
4251 [ + + ]: 120544 : if (op_hashjoinable(opno, exprType(leftarg)) &&
1888 drowley@postgresql.o 4252 [ + + ]: 117926 : !contain_volatile_functions((Node *) restrictinfo))
9784 tgl@sss.pgh.pa.us 4253 : 117920 : restrictinfo->hashjoinoperator = opno;
4254 : : }
4255 : :
4256 : : /*
4257 : : * check_memoizable
4258 : : * If the restrictinfo's clause is suitable to be used for a Memoize node,
4259 : : * set the left_hasheqoperator and right_hasheqoperator to the hash equality
4260 : : * operator that will be needed during caching.
4261 : : */
4262 : : static void
1781 drowley@postgresql.o 4263 : 131821 : check_memoizable(RestrictInfo *restrictinfo)
4264 : : {
4265 : : TypeCacheEntry *typentry;
1884 4266 : 131821 : Expr *clause = restrictinfo->clause;
4267 : : Oid lefttype;
4268 : : Oid righttype;
4269 : :
4270 [ + + ]: 131821 : if (restrictinfo->pseudoconstant)
4271 : 5504 : return;
4272 [ + + ]: 126317 : if (!is_opclause(clause))
4273 : 5773 : return;
4274 [ - + ]: 120544 : if (list_length(((OpExpr *) clause)->args) != 2)
1884 drowley@postgresql.o 4275 :UBC 0 : return;
4276 : :
1664 drowley@postgresql.o 4277 :CBC 120544 : lefttype = exprType(linitial(((OpExpr *) clause)->args));
4278 : :
4279 : 120544 : typentry = lookup_type_cache(lefttype, TYPECACHE_HASH_PROC |
4280 : : TYPECACHE_EQ_OPR);
4281 : :
4282 [ + + + - ]: 120544 : if (OidIsValid(typentry->hash_proc) && OidIsValid(typentry->eq_opr))
4283 : 120204 : restrictinfo->left_hasheqoperator = typentry->eq_opr;
4284 : :
4285 : 120544 : righttype = exprType(lsecond(((OpExpr *) clause)->args));
4286 : :
4287 : : /*
4288 : : * Lookup the right type, unless it's the same as the left type, in which
4289 : : * case typentry is already pointing to the required TypeCacheEntry.
4290 : : */
4291 [ + + ]: 120544 : if (lefttype != righttype)
4292 : 1722 : typentry = lookup_type_cache(righttype, TYPECACHE_HASH_PROC |
4293 : : TYPECACHE_EQ_OPR);
4294 : :
4295 [ + + + - ]: 120544 : if (OidIsValid(typentry->hash_proc) && OidIsValid(typentry->eq_opr))
4296 : 120034 : restrictinfo->right_hasheqoperator = typentry->eq_opr;
4297 : : }
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