Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * pathnode.c
4 : : * Routines to manipulate pathlists and create path nodes
5 : : *
6 : : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
7 : : * Portions Copyright (c) 1994, Regents of the University of California
8 : : *
9 : : *
10 : : * IDENTIFICATION
11 : : * src/backend/optimizer/util/pathnode.c
12 : : *
13 : : *-------------------------------------------------------------------------
14 : : */
15 : : #include "postgres.h"
16 : :
17 : : #include <math.h>
18 : :
19 : : #include "foreign/fdwapi.h"
20 : : #include "miscadmin.h"
21 : : #include "nodes/extensible.h"
22 : : #include "optimizer/appendinfo.h"
23 : : #include "optimizer/clauses.h"
24 : : #include "optimizer/cost.h"
25 : : #include "optimizer/optimizer.h"
26 : : #include "optimizer/pathnode.h"
27 : : #include "optimizer/paths.h"
28 : : #include "optimizer/planmain.h"
29 : : #include "optimizer/tlist.h"
30 : : #include "parser/parsetree.h"
31 : : #include "utils/memutils.h"
32 : : #include "utils/selfuncs.h"
33 : :
34 : : typedef enum
35 : : {
36 : : COSTS_EQUAL, /* path costs are fuzzily equal */
37 : : COSTS_BETTER1, /* first path is cheaper than second */
38 : : COSTS_BETTER2, /* second path is cheaper than first */
39 : : COSTS_DIFFERENT, /* neither path dominates the other on cost */
40 : : } PathCostComparison;
41 : :
42 : : /*
43 : : * STD_FUZZ_FACTOR is the normal fuzz factor for compare_path_costs_fuzzily.
44 : : * XXX is it worth making this user-controllable? It provides a tradeoff
45 : : * between planner runtime and the accuracy of path cost comparisons.
46 : : */
47 : : #define STD_FUZZ_FACTOR 1.01
48 : :
49 : : static int append_total_cost_compare(const ListCell *a, const ListCell *b);
50 : : static int append_startup_cost_compare(const ListCell *a, const ListCell *b);
51 : : static List *reparameterize_pathlist_by_child(PlannerInfo *root,
52 : : List *pathlist,
53 : : RelOptInfo *child_rel);
54 : : static bool pathlist_is_reparameterizable_by_child(List *pathlist,
55 : : RelOptInfo *child_rel);
56 : :
57 : :
58 : : /*****************************************************************************
59 : : * MISC. PATH UTILITIES
60 : : *****************************************************************************/
61 : :
62 : : /*
63 : : * compare_path_costs
64 : : * Return -1, 0, or +1 according as path1 is cheaper, the same cost,
65 : : * or more expensive than path2 for the specified criterion.
66 : : */
67 : : int
9335 tgl@sss.pgh.pa.us 68 :CBC 503232 : compare_path_costs(Path *path1, Path *path2, CostSelector criterion)
69 : : {
70 : : /* Number of disabled nodes, if different, trumps all else. */
381 rhaas@postgresql.org 71 [ + + ]: 503232 : if (unlikely(path1->disabled_nodes != path2->disabled_nodes))
72 : : {
73 [ + - ]: 1352 : if (path1->disabled_nodes < path2->disabled_nodes)
74 : 1352 : return -1;
75 : : else
381 rhaas@postgresql.org 76 :UBC 0 : return +1;
77 : : }
78 : :
9335 tgl@sss.pgh.pa.us 79 [ + + ]:CBC 501880 : if (criterion == STARTUP_COST)
80 : : {
81 [ + + ]: 254770 : if (path1->startup_cost < path2->startup_cost)
82 : 153271 : return -1;
83 [ + + ]: 101499 : if (path1->startup_cost > path2->startup_cost)
84 : 50052 : return +1;
85 : :
86 : : /*
87 : : * If paths have the same startup cost (not at all unlikely), order
88 : : * them by total cost.
89 : : */
90 [ + + ]: 51447 : if (path1->total_cost < path2->total_cost)
91 : 26637 : return -1;
92 [ + + ]: 24810 : if (path1->total_cost > path2->total_cost)
93 : 2263 : return +1;
94 : : }
95 : : else
96 : : {
97 [ + + ]: 247110 : if (path1->total_cost < path2->total_cost)
98 : 232869 : return -1;
99 [ + + ]: 14241 : if (path1->total_cost > path2->total_cost)
100 : 1944 : return +1;
101 : :
102 : : /*
103 : : * If paths have the same total cost, order them by startup cost.
104 : : */
105 [ + + ]: 12297 : if (path1->startup_cost < path2->startup_cost)
106 : 1314 : return -1;
107 [ + + ]: 10983 : if (path1->startup_cost > path2->startup_cost)
108 : 4 : return +1;
109 : : }
110 : 33526 : return 0;
111 : : }
112 : :
113 : : /*
114 : : * compare_fractional_path_costs
115 : : * Return -1, 0, or +1 according as path1 is cheaper, the same cost,
116 : : * or more expensive than path2 for fetching the specified fraction
117 : : * of the total tuples.
118 : : *
119 : : * If fraction is <= 0 or > 1, we interpret it as 1, ie, we select the
120 : : * path with the cheaper total_cost.
121 : : */
122 : : int
123 : 3038 : compare_fractional_path_costs(Path *path1, Path *path2,
124 : : double fraction)
125 : : {
126 : : Cost cost1,
127 : : cost2;
128 : :
129 : : /* Number of disabled nodes, if different, trumps all else. */
381 rhaas@postgresql.org 130 [ + + ]: 3038 : if (unlikely(path1->disabled_nodes != path2->disabled_nodes))
131 : : {
132 [ + - ]: 18 : if (path1->disabled_nodes < path2->disabled_nodes)
133 : 18 : return -1;
134 : : else
381 rhaas@postgresql.org 135 :UBC 0 : return +1;
136 : : }
137 : :
9335 tgl@sss.pgh.pa.us 138 [ + - + + ]:CBC 3020 : if (fraction <= 0.0 || fraction >= 1.0)
139 : 856 : return compare_path_costs(path1, path2, TOTAL_COST);
140 : 2164 : cost1 = path1->startup_cost +
141 : 2164 : fraction * (path1->total_cost - path1->startup_cost);
142 : 2164 : cost2 = path2->startup_cost +
143 : 2164 : fraction * (path2->total_cost - path2->startup_cost);
144 [ + + ]: 2164 : if (cost1 < cost2)
145 : 1790 : return -1;
146 [ + - ]: 374 : if (cost1 > cost2)
147 : 374 : return +1;
9335 tgl@sss.pgh.pa.us 148 :UBC 0 : return 0;
149 : : }
150 : :
151 : : /*
152 : : * compare_path_costs_fuzzily
153 : : * Compare the costs of two paths to see if either can be said to
154 : : * dominate the other.
155 : : *
156 : : * We use fuzzy comparisons so that add_path() can avoid keeping both of
157 : : * a pair of paths that really have insignificantly different cost.
158 : : *
159 : : * The fuzz_factor argument must be 1.0 plus delta, where delta is the
160 : : * fraction of the smaller cost that is considered to be a significant
161 : : * difference. For example, fuzz_factor = 1.01 makes the fuzziness limit
162 : : * be 1% of the smaller cost.
163 : : *
164 : : * The two paths are said to have "equal" costs if both startup and total
165 : : * costs are fuzzily the same. Path1 is said to be better than path2 if
166 : : * it has fuzzily better startup cost and fuzzily no worse total cost,
167 : : * or if it has fuzzily better total cost and fuzzily no worse startup cost.
168 : : * Path2 is better than path1 if the reverse holds. Finally, if one path
169 : : * is fuzzily better than the other on startup cost and fuzzily worse on
170 : : * total cost, we just say that their costs are "different", since neither
171 : : * dominates the other across the whole performance spectrum.
172 : : *
173 : : * This function also enforces a policy rule that paths for which the relevant
174 : : * one of parent->consider_startup and parent->consider_param_startup is false
175 : : * cannot survive comparisons solely on the grounds of good startup cost, so
176 : : * we never return COSTS_DIFFERENT when that is true for the total-cost loser.
177 : : * (But if total costs are fuzzily equal, we compare startup costs anyway,
178 : : * in hopes of eliminating one path or the other.)
179 : : */
180 : : static PathCostComparison
3748 tgl@sss.pgh.pa.us 181 :CBC 2094018 : compare_path_costs_fuzzily(Path *path1, Path *path2, double fuzz_factor)
182 : : {
183 : : #define CONSIDER_PATH_STARTUP_COST(p) \
184 : : ((p)->param_info == NULL ? (p)->parent->consider_startup : (p)->parent->consider_param_startup)
185 : :
186 : : /* Number of disabled nodes, if different, trumps all else. */
381 rhaas@postgresql.org 187 [ + + ]: 2094018 : if (unlikely(path1->disabled_nodes != path2->disabled_nodes))
188 : : {
189 [ + + ]: 15393 : if (path1->disabled_nodes < path2->disabled_nodes)
190 : 8428 : return COSTS_BETTER1;
191 : : else
192 : 6965 : return COSTS_BETTER2;
193 : : }
194 : :
195 : : /*
196 : : * Check total cost first since it's more likely to be different; many
197 : : * paths have zero startup cost.
198 : : */
4886 tgl@sss.pgh.pa.us 199 [ + + ]: 2078625 : if (path1->total_cost > path2->total_cost * fuzz_factor)
200 : : {
201 : : /* path1 fuzzily worse on total cost */
3748 202 [ + + + + ]: 1092131 : if (CONSIDER_PATH_STARTUP_COST(path1) &&
203 [ + + ]: 68727 : path2->startup_cost > path1->startup_cost * fuzz_factor)
204 : : {
205 : : /* ... but path2 fuzzily worse on startup, so DIFFERENT */
4971 206 : 46136 : return COSTS_DIFFERENT;
207 : : }
208 : : /* else path2 dominates */
209 : 1045995 : return COSTS_BETTER2;
210 : : }
4886 211 [ + + ]: 986494 : if (path2->total_cost > path1->total_cost * fuzz_factor)
212 : : {
213 : : /* path2 fuzzily worse on total cost */
3748 214 [ + + + + ]: 511121 : if (CONSIDER_PATH_STARTUP_COST(path2) &&
215 [ + + ]: 30239 : path1->startup_cost > path2->startup_cost * fuzz_factor)
216 : : {
217 : : /* ... but path1 fuzzily worse on startup, so DIFFERENT */
4971 218 : 20037 : return COSTS_DIFFERENT;
219 : : }
220 : : /* else path1 dominates */
221 : 491084 : return COSTS_BETTER1;
222 : : }
223 : : /* fuzzily the same on total cost ... */
3748 224 [ + + ]: 475373 : if (path1->startup_cost > path2->startup_cost * fuzz_factor)
225 : : {
226 : : /* ... but path1 fuzzily worse on startup, so path2 wins */
4971 227 : 187745 : return COSTS_BETTER2;
228 : : }
3748 229 [ + + ]: 287628 : if (path2->startup_cost > path1->startup_cost * fuzz_factor)
230 : : {
231 : : /* ... but path2 fuzzily worse on startup, so path1 wins */
4971 232 : 32077 : return COSTS_BETTER1;
233 : : }
234 : : /* fuzzily the same on both costs */
235 : 255551 : return COSTS_EQUAL;
236 : :
237 : : #undef CONSIDER_PATH_STARTUP_COST
238 : : }
239 : :
240 : : /*
241 : : * set_cheapest
242 : : * Find the minimum-cost paths from among a relation's paths,
243 : : * and save them in the rel's cheapest-path fields.
244 : : *
245 : : * cheapest_total_path is normally the cheapest-total-cost unparameterized
246 : : * path; but if there are no unparameterized paths, we assign it to be the
247 : : * best (cheapest least-parameterized) parameterized path. However, only
248 : : * unparameterized paths are considered candidates for cheapest_startup_path,
249 : : * so that will be NULL if there are no unparameterized paths.
250 : : *
251 : : * The cheapest_parameterized_paths list collects all parameterized paths
252 : : * that have survived the add_path() tournament for this relation. (Since
253 : : * add_path ignores pathkeys for a parameterized path, these will be paths
254 : : * that have best cost or best row count for their parameterization. We
255 : : * may also have both a parallel-safe and a non-parallel-safe path in some
256 : : * cases for the same parameterization in some cases, but this should be
257 : : * relatively rare since, most typically, all paths for the same relation
258 : : * will be parallel-safe or none of them will.)
259 : : *
260 : : * cheapest_parameterized_paths always includes the cheapest-total
261 : : * unparameterized path, too, if there is one; the users of that list find
262 : : * it more convenient if that's included.
263 : : *
264 : : * This is normally called only after we've finished constructing the path
265 : : * list for the rel node.
266 : : */
267 : : void
9335 268 : 1008257 : set_cheapest(RelOptInfo *parent_rel)
269 : : {
270 : : Path *cheapest_startup_path;
271 : : Path *cheapest_total_path;
272 : : Path *best_param_path;
273 : : List *parameterized_paths;
274 : : ListCell *p;
275 : :
9912 bruce@momjian.us 276 [ - + ]: 1008257 : Assert(IsA(parent_rel, RelOptInfo));
277 : :
4756 tgl@sss.pgh.pa.us 278 [ - + ]: 1008257 : if (parent_rel->pathlist == NIL)
4756 tgl@sss.pgh.pa.us 279 [ # # ]:UBC 0 : elog(ERROR, "could not devise a query plan for the given query");
280 : :
4756 tgl@sss.pgh.pa.us 281 :CBC 1008257 : cheapest_startup_path = cheapest_total_path = best_param_path = NULL;
282 : 1008257 : parameterized_paths = NIL;
283 : :
4971 284 [ + - + + : 2277314 : foreach(p, parent_rel->pathlist)
+ + ]
285 : : {
10225 bruce@momjian.us 286 : 1269057 : Path *path = (Path *) lfirst(p);
287 : : int cmp;
288 : :
4888 tgl@sss.pgh.pa.us 289 [ + + ]: 1269057 : if (path->param_info)
290 : : {
291 : : /* Parameterized path, so add it to parameterized_paths */
4756 292 : 65813 : parameterized_paths = lappend(parameterized_paths, path);
293 : :
294 : : /*
295 : : * If we have an unparameterized cheapest-total, we no longer care
296 : : * about finding the best parameterized path, so move on.
297 : : */
298 [ + + ]: 65813 : if (cheapest_total_path)
299 : 13805 : continue;
300 : :
301 : : /*
302 : : * Otherwise, track the best parameterized path, which is the one
303 : : * with least total cost among those of the minimum
304 : : * parameterization.
305 : : */
306 [ + + ]: 52008 : if (best_param_path == NULL)
307 : 47732 : best_param_path = path;
308 : : else
309 : : {
310 [ + - + + : 4276 : switch (bms_subset_compare(PATH_REQ_OUTER(path),
- + - ]
311 [ + - ]: 4276 : PATH_REQ_OUTER(best_param_path)))
312 : : {
313 : 30 : case BMS_EQUAL:
314 : : /* keep the cheaper one */
315 [ - + ]: 30 : if (compare_path_costs(path, best_param_path,
316 : : TOTAL_COST) < 0)
4756 tgl@sss.pgh.pa.us 317 :UBC 0 : best_param_path = path;
4756 tgl@sss.pgh.pa.us 318 :CBC 30 : break;
319 : 197 : case BMS_SUBSET1:
320 : : /* new path is less-parameterized */
321 : 197 : best_param_path = path;
322 : 197 : break;
4756 tgl@sss.pgh.pa.us 323 :LBC (39) : case BMS_SUBSET2:
324 : : /* old path is less-parameterized, keep it */
325 : (39) : break;
4756 tgl@sss.pgh.pa.us 326 :CBC 4049 : case BMS_DIFFERENT:
327 : :
328 : : /*
329 : : * This means that neither path has the least possible
330 : : * parameterization for the rel. We'll sit on the old
331 : : * path until something better comes along.
332 : : */
333 : 4049 : break;
334 : : }
335 : : }
336 : : }
337 : : else
338 : : {
339 : : /* Unparameterized path, so consider it for cheapest slots */
340 [ + + ]: 1203244 : if (cheapest_total_path == NULL)
341 : : {
342 : 1002446 : cheapest_startup_path = cheapest_total_path = path;
343 : 1002446 : continue;
344 : : }
345 : :
346 : : /*
347 : : * If we find two paths of identical costs, try to keep the
348 : : * better-sorted one. The paths might have unrelated sort
349 : : * orderings, in which case we can only guess which might be
350 : : * better to keep, but if one is superior then we definitely
351 : : * should keep that one.
352 : : */
353 : 200798 : cmp = compare_path_costs(cheapest_startup_path, path, STARTUP_COST);
354 [ + + + + ]: 200798 : if (cmp > 0 ||
355 [ - + ]: 197 : (cmp == 0 &&
356 : 197 : compare_pathkeys(cheapest_startup_path->pathkeys,
357 : : path->pathkeys) == PATHKEYS_BETTER2))
358 : 38188 : cheapest_startup_path = path;
359 : :
360 : 200798 : cmp = compare_path_costs(cheapest_total_path, path, TOTAL_COST);
361 [ + - + + ]: 200798 : if (cmp > 0 ||
362 [ - + ]: 24 : (cmp == 0 &&
363 : 24 : compare_pathkeys(cheapest_total_path->pathkeys,
364 : : path->pathkeys) == PATHKEYS_BETTER2))
4756 tgl@sss.pgh.pa.us 365 :UBC 0 : cheapest_total_path = path;
366 : : }
367 : : }
368 : :
369 : : /* Add cheapest unparameterized path, if any, to parameterized_paths */
4756 tgl@sss.pgh.pa.us 370 [ + + ]:CBC 1008257 : if (cheapest_total_path)
371 : 1002446 : parameterized_paths = lcons(cheapest_total_path, parameterized_paths);
372 : :
373 : : /*
374 : : * If there is no unparameterized path, use the best parameterized path as
375 : : * cheapest_total_path (but not as cheapest_startup_path).
376 : : */
377 [ + + ]: 1008257 : if (cheapest_total_path == NULL)
378 : 5811 : cheapest_total_path = best_param_path;
379 [ - + ]: 1008257 : Assert(cheapest_total_path != NULL);
380 : :
9335 381 : 1008257 : parent_rel->cheapest_startup_path = cheapest_startup_path;
382 : 1008257 : parent_rel->cheapest_total_path = cheapest_total_path;
4756 383 : 1008257 : parent_rel->cheapest_parameterized_paths = parameterized_paths;
9343 384 : 1008257 : }
385 : :
386 : : /*
387 : : * add_path
388 : : * Consider a potential implementation path for the specified parent rel,
389 : : * and add it to the rel's pathlist if it is worthy of consideration.
390 : : *
391 : : * A path is worthy if it has a better sort order (better pathkeys) or
392 : : * cheaper cost (as defined below), or generates fewer rows, than any
393 : : * existing path that has the same or superset parameterization rels. We
394 : : * also consider parallel-safe paths more worthy than others.
395 : : *
396 : : * Cheaper cost can mean either a cheaper total cost or a cheaper startup
397 : : * cost; if one path is cheaper in one of these aspects and another is
398 : : * cheaper in the other, we keep both. However, when some path type is
399 : : * disabled (e.g. due to enable_seqscan=false), the number of times that
400 : : * a disabled path type is used is considered to be a higher-order
401 : : * component of the cost. Hence, if path A uses no disabled path type,
402 : : * and path B uses 1 or more disabled path types, A is cheaper, no matter
403 : : * what we estimate for the startup and total costs. The startup and total
404 : : * cost essentially act as a tiebreak when comparing paths that use equal
405 : : * numbers of disabled path nodes; but in practice this tiebreak is almost
406 : : * always used, since normally no path types are disabled.
407 : : *
408 : : * In addition to possibly adding new_path, we also remove from the rel's
409 : : * pathlist any old paths that are dominated by new_path --- that is,
410 : : * new_path is cheaper, at least as well ordered, generates no more rows,
411 : : * requires no outer rels not required by the old path, and is no less
412 : : * parallel-safe.
413 : : *
414 : : * In most cases, a path with a superset parameterization will generate
415 : : * fewer rows (since it has more join clauses to apply), so that those two
416 : : * figures of merit move in opposite directions; this means that a path of
417 : : * one parameterization can seldom dominate a path of another. But such
418 : : * cases do arise, so we make the full set of checks anyway.
419 : : *
420 : : * There are two policy decisions embedded in this function, along with
421 : : * its sibling add_path_precheck. First, we treat all parameterized paths
422 : : * as having NIL pathkeys, so that they cannot win comparisons on the
423 : : * basis of sort order. This is to reduce the number of parameterized
424 : : * paths that are kept; see discussion in src/backend/optimizer/README.
425 : : *
426 : : * Second, we only consider cheap startup cost to be interesting if
427 : : * parent_rel->consider_startup is true for an unparameterized path, or
428 : : * parent_rel->consider_param_startup is true for a parameterized one.
429 : : * Again, this allows discarding useless paths sooner.
430 : : *
431 : : * The pathlist is kept sorted by disabled_nodes and then by total_cost,
432 : : * with cheaper paths at the front. Within this routine, that's simply a
433 : : * speed hack: doing it that way makes it more likely that we will reject
434 : : * an inferior path after a few comparisons, rather than many comparisons.
435 : : * However, add_path_precheck relies on this ordering to exit early
436 : : * when possible.
437 : : *
438 : : * NOTE: discarded Path objects are immediately pfree'd to reduce planner
439 : : * memory consumption. We dare not try to free the substructure of a Path,
440 : : * since much of it may be shared with other Paths or the query tree itself;
441 : : * but just recycling discarded Path nodes is a very useful savings in
442 : : * a large join tree. We can recycle the List nodes of pathlist, too.
443 : : *
444 : : * As noted in optimizer/README, deleting a previously-accepted Path is
445 : : * safe because we know that Paths of this rel cannot yet be referenced
446 : : * from any other rel, such as a higher-level join. However, in some cases
447 : : * it is possible that a Path is referenced by another Path for its own
448 : : * rel; we must not delete such a Path, even if it is dominated by the new
449 : : * Path. Currently this occurs only for IndexPath objects, which may be
450 : : * referenced as children of BitmapHeapPaths as well as being paths in
451 : : * their own right. Hence, we don't pfree IndexPaths when rejecting them.
452 : : *
453 : : * 'parent_rel' is the relation entry to which the path corresponds.
454 : : * 'new_path' is a potential path for parent_rel.
455 : : *
456 : : * Returns nothing, but modifies parent_rel->pathlist.
457 : : */
458 : : void
459 : 2116116 : add_path(RelOptInfo *parent_rel, Path *new_path)
460 : : {
2999 461 : 2116116 : bool accept_new = true; /* unless we find a superior old path */
2245 462 : 2116116 : int insert_at = 0; /* where to insert new item */
463 : : List *new_path_pathkeys;
464 : : ListCell *p1;
465 : :
466 : : /*
467 : : * This is a convenient place to check for query cancel --- no part of the
468 : : * planner goes very long without calling add_path().
469 : : */
7400 470 [ + + ]: 2116116 : CHECK_FOR_INTERRUPTS();
471 : :
472 : : /* Pretend parameterized paths have no pathkeys, per comment above */
4888 473 [ + + ]: 2116116 : new_path_pathkeys = new_path->param_info ? NIL : new_path->pathkeys;
474 : :
475 : : /*
476 : : * Loop to check proposed new path against old paths. Note it is possible
477 : : * for more than one old path to be tossed out because new_path dominates
478 : : * it.
479 : : */
2245 480 [ + + + + : 3264871 : foreach(p1, parent_rel->pathlist)
+ + ]
481 : : {
9343 482 : 1929811 : Path *old_path = (Path *) lfirst(p1);
9278 bruce@momjian.us 483 : 1929811 : bool remove_old = false; /* unless new proves superior */
484 : : PathCostComparison costcmp;
485 : : PathKeysComparison keyscmp;
486 : : BMS_Comparison outercmp;
487 : :
488 : : /*
489 : : * Do a fuzzy cost comparison with standard fuzziness limit.
490 : : */
3748 tgl@sss.pgh.pa.us 491 : 1929811 : costcmp = compare_path_costs_fuzzily(new_path, old_path,
492 : : STD_FUZZ_FACTOR);
493 : :
494 : : /*
495 : : * If the two paths compare differently for startup and total cost,
496 : : * then we want to keep both, and we can skip comparing pathkeys and
497 : : * required_outer rels. If they compare the same, proceed with the
498 : : * other comparisons. Row count is checked last. (We make the tests
499 : : * in this order because the cost comparison is most likely to turn
500 : : * out "different", and the pathkeys comparison next most likely. As
501 : : * explained above, row count very seldom makes a difference, so even
502 : : * though it's cheap to compare there's not much point in checking it
503 : : * earlier.)
504 : : */
4971 505 [ + + ]: 1929811 : if (costcmp != COSTS_DIFFERENT)
506 : : {
507 : : /* Similarly check to see if either dominates on pathkeys */
508 : : List *old_path_pathkeys;
509 : :
4888 510 [ + + ]: 1863671 : old_path_pathkeys = old_path->param_info ? NIL : old_path->pathkeys;
4971 511 : 1863671 : keyscmp = compare_pathkeys(new_path_pathkeys,
512 : : old_path_pathkeys);
513 [ + + ]: 1863671 : if (keyscmp != PATHKEYS_DIFFERENT)
514 : : {
515 [ + + + - : 1773025 : switch (costcmp)
- ]
516 : : {
517 : 180333 : case COSTS_EQUAL:
4888 518 [ + + ]: 180333 : outercmp = bms_subset_compare(PATH_REQ_OUTER(new_path),
2999 519 [ + + ]: 180333 : PATH_REQ_OUTER(old_path));
4971 520 [ + + ]: 180333 : if (keyscmp == PATHKEYS_BETTER1)
521 : : {
4888 522 [ + + + - ]: 3678 : if ((outercmp == BMS_EQUAL ||
523 : 3678 : outercmp == BMS_SUBSET1) &&
3517 rhaas@postgresql.org 524 [ + + ]: 3678 : new_path->rows <= old_path->rows &&
525 [ + - ]: 3674 : new_path->parallel_safe >= old_path->parallel_safe)
2999 tgl@sss.pgh.pa.us 526 : 3674 : remove_old = true; /* new dominates old */
527 : : }
4971 528 [ + + ]: 176655 : else if (keyscmp == PATHKEYS_BETTER2)
529 : : {
4888 530 [ + + + - ]: 9604 : if ((outercmp == BMS_EQUAL ||
531 : 9604 : outercmp == BMS_SUBSET2) &&
3517 rhaas@postgresql.org 532 [ + + ]: 9604 : new_path->rows >= old_path->rows &&
533 [ + - ]: 9603 : new_path->parallel_safe <= old_path->parallel_safe)
2999 tgl@sss.pgh.pa.us 534 : 9603 : accept_new = false; /* old dominates new */
535 : : }
536 : : else /* keyscmp == PATHKEYS_EQUAL */
537 : : {
4971 538 [ + + ]: 167051 : if (outercmp == BMS_EQUAL)
539 : : {
540 : : /*
541 : : * Same pathkeys and outer rels, and fuzzily
542 : : * the same cost, so keep just one; to decide
543 : : * which, first check parallel-safety, then
544 : : * rows, then do a fuzzy cost comparison with
545 : : * very small fuzz limit. (We used to do an
546 : : * exact cost comparison, but that results in
547 : : * annoying platform-specific plan variations
548 : : * due to roundoff in the cost estimates.) If
549 : : * things are still tied, arbitrarily keep
550 : : * only the old path. Notice that we will
551 : : * keep only the old path even if the
552 : : * less-fuzzy comparison decides the startup
553 : : * and total costs compare differently.
554 : : */
3517 rhaas@postgresql.org 555 : 164350 : if (new_path->parallel_safe >
556 [ + + ]: 164350 : old_path->parallel_safe)
557 : 21 : remove_old = true; /* new dominates old */
558 : 164329 : else if (new_path->parallel_safe <
559 [ + + ]: 164329 : old_path->parallel_safe)
560 : 27 : accept_new = false; /* old dominates new */
561 [ - + ]: 164302 : else if (new_path->rows < old_path->rows)
4888 tgl@sss.pgh.pa.us 562 :UBC 0 : remove_old = true; /* new dominates old */
4888 tgl@sss.pgh.pa.us 563 [ + + ]:CBC 164302 : else if (new_path->rows > old_path->rows)
4836 bruce@momjian.us 564 : 95 : accept_new = false; /* old dominates new */
4753 tgl@sss.pgh.pa.us 565 [ + + ]: 164207 : else if (compare_path_costs_fuzzily(new_path,
566 : : old_path,
567 : : 1.0000000001) == COSTS_BETTER1)
4971 568 : 8887 : remove_old = true; /* new dominates old */
569 : : else
4836 bruce@momjian.us 570 : 155320 : accept_new = false; /* old equals or
571 : : * dominates new */
572 : : }
4888 tgl@sss.pgh.pa.us 573 [ + + ]: 2701 : else if (outercmp == BMS_SUBSET1 &&
3517 rhaas@postgresql.org 574 [ + + ]: 620 : new_path->rows <= old_path->rows &&
575 [ + - ]: 610 : new_path->parallel_safe >= old_path->parallel_safe)
2999 tgl@sss.pgh.pa.us 576 : 610 : remove_old = true; /* new dominates old */
4888 577 [ + + ]: 2091 : else if (outercmp == BMS_SUBSET2 &&
3517 rhaas@postgresql.org 578 [ + + ]: 1740 : new_path->rows >= old_path->rows &&
579 [ + - ]: 1482 : new_path->parallel_safe <= old_path->parallel_safe)
2999 tgl@sss.pgh.pa.us 580 : 1482 : accept_new = false; /* old dominates new */
581 : : /* else different parameterizations, keep both */
582 : : }
4971 583 : 180333 : break;
584 : 510155 : case COSTS_BETTER1:
585 [ + + ]: 510155 : if (keyscmp != PATHKEYS_BETTER2)
586 : : {
4888 587 [ + + ]: 354727 : outercmp = bms_subset_compare(PATH_REQ_OUTER(new_path),
2999 588 [ + + ]: 354727 : PATH_REQ_OUTER(old_path));
4888 589 [ + + + + ]: 354727 : if ((outercmp == BMS_EQUAL ||
590 : 303928 : outercmp == BMS_SUBSET1) &&
3517 rhaas@postgresql.org 591 [ + + ]: 303928 : new_path->rows <= old_path->rows &&
592 [ + + ]: 301220 : new_path->parallel_safe >= old_path->parallel_safe)
2999 tgl@sss.pgh.pa.us 593 : 299951 : remove_old = true; /* new dominates old */
594 : : }
4971 595 : 510155 : break;
596 : 1082537 : case COSTS_BETTER2:
597 [ + + ]: 1082537 : if (keyscmp != PATHKEYS_BETTER1)
598 : : {
4888 599 [ + + ]: 692357 : outercmp = bms_subset_compare(PATH_REQ_OUTER(new_path),
2999 600 [ + + ]: 692357 : PATH_REQ_OUTER(old_path));
4888 601 [ + + + + ]: 692357 : if ((outercmp == BMS_EQUAL ||
602 : 650534 : outercmp == BMS_SUBSET2) &&
3517 rhaas@postgresql.org 603 [ + + ]: 650534 : new_path->rows >= old_path->rows &&
604 [ + + ]: 615392 : new_path->parallel_safe <= old_path->parallel_safe)
2999 tgl@sss.pgh.pa.us 605 : 614529 : accept_new = false; /* old dominates new */
606 : : }
4971 607 : 1082537 : break;
4971 tgl@sss.pgh.pa.us 608 :UBC 0 : case COSTS_DIFFERENT:
609 : :
610 : : /*
611 : : * can't get here, but keep this case to keep compiler
612 : : * quiet
613 : : */
614 : 0 : break;
615 : : }
616 : : }
617 : : }
618 : :
619 : : /*
620 : : * Remove current element from pathlist if dominated by new.
621 : : */
7804 neilc@samurai.com 622 [ + + ]:CBC 1929811 : if (remove_old)
623 : : {
2245 tgl@sss.pgh.pa.us 624 : 313143 : parent_rel->pathlist = foreach_delete_current(parent_rel->pathlist,
625 : : p1);
626 : :
627 : : /*
628 : : * Delete the data pointed-to by the deleted cell, if possible
629 : : */
7442 630 [ + + ]: 313143 : if (!IsA(old_path, IndexPath))
631 : 303990 : pfree(old_path);
632 : : }
633 : : else
634 : : {
635 : : /*
636 : : * new belongs after this old path if it has more disabled nodes
637 : : * or if it has the same number of nodes but a greater total cost
638 : : */
381 rhaas@postgresql.org 639 [ + + ]: 1616668 : if (new_path->disabled_nodes > old_path->disabled_nodes ||
640 [ + + ]: 1609703 : (new_path->disabled_nodes == old_path->disabled_nodes &&
641 [ + + ]: 1609221 : new_path->total_cost >= old_path->total_cost))
2245 tgl@sss.pgh.pa.us 642 : 1346942 : insert_at = foreach_current_index(p1) + 1;
643 : : }
644 : :
645 : : /*
646 : : * If we found an old path that dominates new_path, we can quit
647 : : * scanning the pathlist; we will not add new_path, and we assume
648 : : * new_path cannot dominate any other elements of the pathlist.
649 : : */
9278 bruce@momjian.us 650 [ + + ]: 1929811 : if (!accept_new)
9343 tgl@sss.pgh.pa.us 651 : 781056 : break;
652 : : }
653 : :
654 [ + + ]: 2116116 : if (accept_new)
655 : : {
656 : : /* Accept the new path: insert it at proper place in pathlist */
2245 657 : 1335060 : parent_rel->pathlist =
658 : 1335060 : list_insert_nth(parent_rel->pathlist, insert_at, new_path);
659 : : }
660 : : else
661 : : {
662 : : /* Reject and recycle the new path */
7442 663 [ + + ]: 781056 : if (!IsA(new_path, IndexPath))
664 : 733468 : pfree(new_path);
665 : : }
10651 scrappy@hub.org 666 : 2116116 : }
667 : :
668 : : /*
669 : : * add_path_precheck
670 : : * Check whether a proposed new path could possibly get accepted.
671 : : * We assume we know the path's pathkeys and parameterization accurately,
672 : : * and have lower bounds for its costs.
673 : : *
674 : : * Note that we do not know the path's rowcount, since getting an estimate for
675 : : * that is too expensive to do before prechecking. We assume here that paths
676 : : * of a superset parameterization will generate fewer rows; if that holds,
677 : : * then paths with different parameterizations cannot dominate each other
678 : : * and so we can simply ignore existing paths of another parameterization.
679 : : * (In the infrequent cases where that rule of thumb fails, add_path will
680 : : * get rid of the inferior path.)
681 : : *
682 : : * At the time this is called, we haven't actually built a Path structure,
683 : : * so the required information has to be passed piecemeal.
684 : : */
685 : : bool
381 rhaas@postgresql.org 686 : 2251572 : add_path_precheck(RelOptInfo *parent_rel, int disabled_nodes,
687 : : Cost startup_cost, Cost total_cost,
688 : : List *pathkeys, Relids required_outer)
689 : : {
690 : : List *new_path_pathkeys;
691 : : bool consider_startup;
692 : : ListCell *p1;
693 : :
694 : : /* Pretend parameterized paths have no pathkeys, per add_path policy */
4971 tgl@sss.pgh.pa.us 695 [ + + ]: 2251572 : new_path_pathkeys = required_outer ? NIL : pathkeys;
696 : :
697 : : /* Decide whether new path's startup cost is interesting */
3748 698 [ + + ]: 2251572 : consider_startup = required_outer ? parent_rel->consider_param_startup : parent_rel->consider_startup;
699 : :
4971 700 [ + + + + : 2937011 : foreach(p1, parent_rel->pathlist)
+ + ]
701 : : {
702 : 2788376 : Path *old_path = (Path *) lfirst(p1);
703 : : PathKeysComparison keyscmp;
704 : :
705 : : /*
706 : : * Since the pathlist is sorted by disabled_nodes and then by
707 : : * total_cost, we can stop looking once we reach a path with more
708 : : * disabled nodes, or the same number of disabled nodes plus a
709 : : * total_cost larger than the new path's.
710 : : */
381 rhaas@postgresql.org 711 [ + + ]: 2788376 : if (unlikely(old_path->disabled_nodes != disabled_nodes))
712 : : {
713 [ + + ]: 6459 : if (disabled_nodes < old_path->disabled_nodes)
714 : 159 : break;
715 : : }
716 [ + + ]: 2781917 : else if (total_cost <= old_path->total_cost * STD_FUZZ_FACTOR)
717 : 809389 : break;
718 : :
719 : : /*
720 : : * We are looking for an old_path with the same parameterization (and
721 : : * by assumption the same rowcount) that dominates the new path on
722 : : * pathkeys as well as both cost metrics. If we find one, we can
723 : : * reject the new path.
724 : : *
725 : : * Cost comparisons here should match compare_path_costs_fuzzily.
726 : : */
727 : : /* new path can win on startup cost only if consider_startup */
728 [ + + ]: 1978828 : if (startup_cost > old_path->startup_cost * STD_FUZZ_FACTOR ||
729 [ + + ]: 937121 : !consider_startup)
730 : : {
731 : : /* new path loses on cost, so check pathkeys... */
732 : : List *old_path_pathkeys;
733 : :
734 [ + + ]: 1927127 : old_path_pathkeys = old_path->param_info ? NIL : old_path->pathkeys;
735 : 1927127 : keyscmp = compare_pathkeys(new_path_pathkeys,
736 : : old_path_pathkeys);
737 [ + + + + ]: 1927127 : if (keyscmp == PATHKEYS_EQUAL ||
738 : : keyscmp == PATHKEYS_BETTER2)
739 : : {
740 : : /* new path does not win on pathkeys... */
741 [ + + + + ]: 1325789 : if (bms_equal(required_outer, PATH_REQ_OUTER(old_path)))
742 : : {
743 : : /* Found an old path that dominates the new one */
744 : 1293389 : return false;
745 : : }
746 : : }
747 : : }
748 : : }
749 : :
4971 tgl@sss.pgh.pa.us 750 : 958183 : return true;
751 : : }
752 : :
753 : : /*
754 : : * add_partial_path
755 : : * Like add_path, our goal here is to consider whether a path is worthy
756 : : * of being kept around, but the considerations here are a bit different.
757 : : * A partial path is one which can be executed in any number of workers in
758 : : * parallel such that each worker will generate a subset of the path's
759 : : * overall result.
760 : : *
761 : : * As in add_path, the partial_pathlist is kept sorted with the cheapest
762 : : * total path in front. This is depended on by multiple places, which
763 : : * just take the front entry as the cheapest path without searching.
764 : : *
765 : : * We don't generate parameterized partial paths for several reasons. Most
766 : : * importantly, they're not safe to execute, because there's nothing to
767 : : * make sure that a parallel scan within the parameterized portion of the
768 : : * plan is running with the same value in every worker at the same time.
769 : : * Fortunately, it seems unlikely to be worthwhile anyway, because having
770 : : * each worker scan the entire outer relation and a subset of the inner
771 : : * relation will generally be a terrible plan. The inner (parameterized)
772 : : * side of the plan will be small anyway. There could be rare cases where
773 : : * this wins big - e.g. if join order constraints put a 1-row relation on
774 : : * the outer side of the topmost join with a parameterized plan on the inner
775 : : * side - but we'll have to be content not to handle such cases until
776 : : * somebody builds an executor infrastructure that can cope with them.
777 : : *
778 : : * Because we don't consider parameterized paths here, we also don't
779 : : * need to consider the row counts as a measure of quality: every path will
780 : : * produce the same number of rows. Neither do we need to consider startup
781 : : * costs: parallelism is only used for plans that will be run to completion.
782 : : * Therefore, this routine is much simpler than add_path: it needs to
783 : : * consider only disabled nodes, pathkeys and total cost.
784 : : *
785 : : * As with add_path, we pfree paths that are found to be dominated by
786 : : * another partial path; this requires that there be no other references to
787 : : * such paths yet. Hence, GatherPaths must not be created for a rel until
788 : : * we're done creating all partial paths for it. Unlike add_path, we don't
789 : : * take an exception for IndexPaths as partial index paths won't be
790 : : * referenced by partial BitmapHeapPaths.
791 : : */
792 : : void
3517 rhaas@postgresql.org 793 : 56182 : add_partial_path(RelOptInfo *parent_rel, Path *new_path)
794 : : {
2999 tgl@sss.pgh.pa.us 795 : 56182 : bool accept_new = true; /* unless we find a superior old path */
2245 796 : 56182 : int insert_at = 0; /* where to insert new item */
797 : : ListCell *p1;
798 : :
799 : : /* Check for query cancel. */
3517 rhaas@postgresql.org 800 [ - + ]: 56182 : CHECK_FOR_INTERRUPTS();
801 : :
802 : : /* Path to be added must be parallel safe. */
2691 803 [ - + ]: 56182 : Assert(new_path->parallel_safe);
804 : :
805 : : /* Relation should be OK for parallelism, too. */
806 [ - + ]: 56182 : Assert(parent_rel->consider_parallel);
807 : :
808 : : /*
809 : : * As in add_path, throw out any paths which are dominated by the new
810 : : * path, but throw out the new path if some existing path dominates it.
811 : : */
2245 tgl@sss.pgh.pa.us 812 [ + + + + : 75793 : foreach(p1, parent_rel->partial_pathlist)
+ + ]
813 : : {
3517 rhaas@postgresql.org 814 : 30111 : Path *old_path = (Path *) lfirst(p1);
815 : 30111 : bool remove_old = false; /* unless new proves superior */
816 : : PathKeysComparison keyscmp;
817 : :
818 : : /* Compare pathkeys. */
819 : 30111 : keyscmp = compare_pathkeys(new_path->pathkeys, old_path->pathkeys);
820 : :
821 : : /* Unless pathkeys are incompatible, keep just one of the two paths. */
822 [ + + ]: 30111 : if (keyscmp != PATHKEYS_DIFFERENT)
823 : : {
381 824 [ + + ]: 30006 : if (unlikely(new_path->disabled_nodes != old_path->disabled_nodes))
825 : : {
826 [ + + ]: 742 : if (new_path->disabled_nodes > old_path->disabled_nodes)
827 : 478 : accept_new = false;
828 : : else
829 : 264 : remove_old = true;
830 : : }
831 : 29264 : else if (new_path->total_cost > old_path->total_cost
832 [ + + ]: 29264 : * STD_FUZZ_FACTOR)
833 : : {
834 : : /* New path costs more; keep it only if pathkeys are better. */
3517 835 [ + + ]: 10201 : if (keyscmp != PATHKEYS_BETTER1)
836 : 5438 : accept_new = false;
837 : : }
838 : 19063 : else if (old_path->total_cost > new_path->total_cost
839 [ + + ]: 19063 : * STD_FUZZ_FACTOR)
840 : : {
841 : : /* Old path costs more; keep it only if pathkeys are better. */
842 [ + + ]: 14242 : if (keyscmp != PATHKEYS_BETTER2)
843 : 6501 : remove_old = true;
844 : : }
845 [ - + ]: 4821 : else if (keyscmp == PATHKEYS_BETTER1)
846 : : {
847 : : /* Costs are about the same, new path has better pathkeys. */
3517 rhaas@postgresql.org 848 :UBC 0 : remove_old = true;
849 : : }
3517 rhaas@postgresql.org 850 [ + + ]:CBC 4821 : else if (keyscmp == PATHKEYS_BETTER2)
851 : : {
852 : : /* Costs are about the same, old path has better pathkeys. */
853 : 1017 : accept_new = false;
854 : : }
855 [ + + ]: 3804 : else if (old_path->total_cost > new_path->total_cost * 1.0000000001)
856 : : {
857 : : /* Pathkeys are the same, and the old path costs more. */
858 : 237 : remove_old = true;
859 : : }
860 : : else
861 : : {
862 : : /*
863 : : * Pathkeys are the same, and new path isn't materially
864 : : * cheaper.
865 : : */
866 : 3567 : accept_new = false;
867 : : }
868 : : }
869 : :
870 : : /*
871 : : * Remove current element from partial_pathlist if dominated by new.
872 : : */
873 [ + + ]: 30111 : if (remove_old)
874 : : {
875 : 7002 : parent_rel->partial_pathlist =
2245 tgl@sss.pgh.pa.us 876 : 7002 : foreach_delete_current(parent_rel->partial_pathlist, p1);
3517 rhaas@postgresql.org 877 : 7002 : pfree(old_path);
878 : : }
879 : : else
880 : : {
881 : : /* new belongs after this old path if it has cost >= old's */
882 [ + + ]: 23109 : if (new_path->total_cost >= old_path->total_cost)
2245 tgl@sss.pgh.pa.us 883 : 14782 : insert_at = foreach_current_index(p1) + 1;
884 : : }
885 : :
886 : : /*
887 : : * If we found an old path that dominates new_path, we can quit
888 : : * scanning the partial_pathlist; we will not add new_path, and we
889 : : * assume new_path cannot dominate any later path.
890 : : */
3517 rhaas@postgresql.org 891 [ + + ]: 30111 : if (!accept_new)
892 : 10500 : break;
893 : : }
894 : :
895 [ + + ]: 56182 : if (accept_new)
896 : : {
897 : : /* Accept the new path: insert it at proper place */
2245 tgl@sss.pgh.pa.us 898 : 45682 : parent_rel->partial_pathlist =
899 : 45682 : list_insert_nth(parent_rel->partial_pathlist, insert_at, new_path);
900 : : }
901 : : else
902 : : {
903 : : /* Reject and recycle the new path */
3517 rhaas@postgresql.org 904 : 10500 : pfree(new_path);
905 : : }
906 : 56182 : }
907 : :
908 : : /*
909 : : * add_partial_path_precheck
910 : : * Check whether a proposed new partial path could possibly get accepted.
911 : : *
912 : : * Unlike add_path_precheck, we can ignore startup cost and parameterization,
913 : : * since they don't matter for partial paths (see add_partial_path). But
914 : : * we do want to make sure we don't add a partial path if there's already
915 : : * a complete path that dominates it, since in that case the proposed path
916 : : * is surely a loser.
917 : : */
918 : : bool
381 919 : 43559 : add_partial_path_precheck(RelOptInfo *parent_rel, int disabled_nodes,
920 : : Cost total_cost, List *pathkeys)
921 : : {
922 : : ListCell *p1;
923 : :
924 : : /*
925 : : * Our goal here is twofold. First, we want to find out whether this path
926 : : * is clearly inferior to some existing partial path. If so, we want to
927 : : * reject it immediately. Second, we want to find out whether this path
928 : : * is clearly superior to some existing partial path -- at least, modulo
929 : : * final cost computations. If so, we definitely want to consider it.
930 : : *
931 : : * Unlike add_path(), we always compare pathkeys here. This is because we
932 : : * expect partial_pathlist to be very short, and getting a definitive
933 : : * answer at this stage avoids the need to call add_path_precheck.
934 : : */
3517 935 [ + + + + : 59248 : foreach(p1, parent_rel->partial_pathlist)
+ + ]
936 : : {
937 : 48423 : Path *old_path = (Path *) lfirst(p1);
938 : : PathKeysComparison keyscmp;
939 : :
940 : 48423 : keyscmp = compare_pathkeys(pathkeys, old_path->pathkeys);
941 [ + + ]: 48423 : if (keyscmp != PATHKEYS_DIFFERENT)
942 : : {
943 [ + + + + ]: 48327 : if (total_cost > old_path->total_cost * STD_FUZZ_FACTOR &&
944 : : keyscmp != PATHKEYS_BETTER1)
945 : 32734 : return false;
946 [ + + + + ]: 23603 : if (old_path->total_cost > total_cost * STD_FUZZ_FACTOR &&
947 : : keyscmp != PATHKEYS_BETTER2)
948 : 8010 : return true;
949 : : }
950 : : }
951 : :
952 : : /*
953 : : * This path is neither clearly inferior to an existing partial path nor
954 : : * clearly good enough that it might replace one. Compare it to
955 : : * non-parallel plans. If it loses even before accounting for the cost of
956 : : * the Gather node, we should definitely reject it.
957 : : *
958 : : * Note that we pass the total_cost to add_path_precheck twice. This is
959 : : * because it's never advantageous to consider the startup cost of a
960 : : * partial path; the resulting plans, if run in parallel, will be run to
961 : : * completion.
962 : : */
381 963 [ + + ]: 10825 : if (!add_path_precheck(parent_rel, disabled_nodes, total_cost, total_cost,
964 : : pathkeys, NULL))
3517 965 : 1179 : return false;
966 : :
967 : 9646 : return true;
968 : : }
969 : :
970 : :
971 : : /*****************************************************************************
972 : : * PATH NODE CREATION ROUTINES
973 : : *****************************************************************************/
974 : :
975 : : /*
976 : : * create_seqscan_path
977 : : * Creates a path corresponding to a sequential scan, returning the
978 : : * pathnode.
979 : : */
980 : : Path *
3587 981 : 209568 : create_seqscan_path(PlannerInfo *root, RelOptInfo *rel,
982 : : Relids required_outer, int parallel_workers)
983 : : {
10225 bruce@momjian.us 984 : 209568 : Path *pathnode = makeNode(Path);
985 : :
10226 986 : 209568 : pathnode->pathtype = T_SeqScan;
987 : 209568 : pathnode->parent = rel;
3463 tgl@sss.pgh.pa.us 988 : 209568 : pathnode->pathtarget = rel->reltarget;
4888 989 : 209568 : pathnode->param_info = get_baserel_parampathinfo(root, rel,
990 : : required_outer);
1459 michael@paquier.xyz 991 : 209568 : pathnode->parallel_aware = (parallel_workers > 0);
3517 rhaas@postgresql.org 992 : 209568 : pathnode->parallel_safe = rel->consider_parallel;
3376 993 : 209568 : pathnode->parallel_workers = parallel_workers;
9518 tgl@sss.pgh.pa.us 994 : 209568 : pathnode->pathkeys = NIL; /* seqscan has unordered result */
995 : :
3517 rhaas@postgresql.org 996 : 209568 : cost_seqscan(pathnode, root, rel, pathnode->param_info);
997 : :
9867 bruce@momjian.us 998 : 209568 : return pathnode;
999 : : }
1000 : :
1001 : : /*
1002 : : * create_samplescan_path
1003 : : * Creates a path node for a sampled table scan.
1004 : : */
1005 : : Path *
3767 simon@2ndQuadrant.co 1006 : 153 : create_samplescan_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer)
1007 : : {
3759 bruce@momjian.us 1008 : 153 : Path *pathnode = makeNode(Path);
1009 : :
3767 simon@2ndQuadrant.co 1010 : 153 : pathnode->pathtype = T_SampleScan;
1011 : 153 : pathnode->parent = rel;
3463 tgl@sss.pgh.pa.us 1012 : 153 : pathnode->pathtarget = rel->reltarget;
3767 simon@2ndQuadrant.co 1013 : 153 : pathnode->param_info = get_baserel_parampathinfo(root, rel,
1014 : : required_outer);
3587 rhaas@postgresql.org 1015 : 153 : pathnode->parallel_aware = false;
3517 1016 : 153 : pathnode->parallel_safe = rel->consider_parallel;
3376 1017 : 153 : pathnode->parallel_workers = 0;
3767 simon@2ndQuadrant.co 1018 : 153 : pathnode->pathkeys = NIL; /* samplescan has unordered result */
1019 : :
3696 tgl@sss.pgh.pa.us 1020 : 153 : cost_samplescan(pathnode, root, rel, pathnode->param_info);
1021 : :
3767 simon@2ndQuadrant.co 1022 : 153 : return pathnode;
1023 : : }
1024 : :
1025 : : /*
1026 : : * create_index_path
1027 : : * Creates a path node for an index scan.
1028 : : *
1029 : : * 'index' is a usable index.
1030 : : * 'indexclauses' is a list of IndexClause nodes representing clauses
1031 : : * to be enforced as qual conditions in the scan.
1032 : : * 'indexorderbys' is a list of bare expressions (no RestrictInfos)
1033 : : * to be used as index ordering operators in the scan.
1034 : : * 'indexorderbycols' is an integer list of index column numbers (zero based)
1035 : : * the ordering operators can be used with.
1036 : : * 'pathkeys' describes the ordering of the path.
1037 : : * 'indexscandir' is either ForwardScanDirection or BackwardScanDirection.
1038 : : * 'indexonly' is true if an index-only scan is wanted.
1039 : : * 'required_outer' is the set of outer relids for a parameterized path.
1040 : : * 'loop_count' is the number of repetitions of the indexscan to factor into
1041 : : * estimates of caching behavior.
1042 : : * 'partial_path' is true if constructing a parallel index scan path.
1043 : : *
1044 : : * Returns the new path node.
1045 : : */
1046 : : IndexPath *
7398 tgl@sss.pgh.pa.us 1047 : 382230 : create_index_path(PlannerInfo *root,
1048 : : IndexOptInfo *index,
1049 : : List *indexclauses,
1050 : : List *indexorderbys,
1051 : : List *indexorderbycols,
1052 : : List *pathkeys,
1053 : : ScanDirection indexscandir,
1054 : : bool indexonly,
1055 : : Relids required_outer,
1056 : : double loop_count,
1057 : : bool partial_path)
1058 : : {
10225 bruce@momjian.us 1059 : 382230 : IndexPath *pathnode = makeNode(IndexPath);
7442 tgl@sss.pgh.pa.us 1060 : 382230 : RelOptInfo *rel = index->rel;
1061 : :
5079 1062 [ + + ]: 382230 : pathnode->path.pathtype = indexonly ? T_IndexOnlyScan : T_IndexScan;
7442 1063 : 382230 : pathnode->path.parent = rel;
3463 1064 : 382230 : pathnode->path.pathtarget = rel->reltarget;
4888 1065 : 382230 : pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1066 : : required_outer);
3587 rhaas@postgresql.org 1067 : 382230 : pathnode->path.parallel_aware = false;
3517 1068 : 382230 : pathnode->path.parallel_safe = rel->consider_parallel;
3376 1069 : 382230 : pathnode->path.parallel_workers = 0;
9032 tgl@sss.pgh.pa.us 1070 : 382230 : pathnode->path.pathkeys = pathkeys;
1071 : :
7439 1072 : 382230 : pathnode->indexinfo = index;
5005 1073 : 382230 : pathnode->indexclauses = indexclauses;
5392 1074 : 382230 : pathnode->indexorderbys = indexorderbys;
5005 1075 : 382230 : pathnode->indexorderbycols = indexorderbycols;
9335 1076 : 382230 : pathnode->indexscandir = indexscandir;
1077 : :
3125 rhaas@postgresql.org 1078 : 382230 : cost_index(pathnode, root, loop_count, partial_path);
1079 : :
9867 bruce@momjian.us 1080 : 382230 : return pathnode;
1081 : : }
1082 : :
1083 : : /*
1084 : : * create_bitmap_heap_path
1085 : : * Creates a path node for a bitmap scan.
1086 : : *
1087 : : * 'bitmapqual' is a tree of IndexPath, BitmapAndPath, and BitmapOrPath nodes.
1088 : : * 'required_outer' is the set of outer relids for a parameterized path.
1089 : : * 'loop_count' is the number of repetitions of the indexscan to factor into
1090 : : * estimates of caching behavior.
1091 : : *
1092 : : * loop_count should match the value used when creating the component
1093 : : * IndexPaths.
1094 : : */
1095 : : BitmapHeapPath *
7398 tgl@sss.pgh.pa.us 1096 : 167389 : create_bitmap_heap_path(PlannerInfo *root,
1097 : : RelOptInfo *rel,
1098 : : Path *bitmapqual,
1099 : : Relids required_outer,
1100 : : double loop_count,
1101 : : int parallel_degree)
1102 : : {
7445 1103 : 167389 : BitmapHeapPath *pathnode = makeNode(BitmapHeapPath);
1104 : :
1105 : 167389 : pathnode->path.pathtype = T_BitmapHeapScan;
1106 : 167389 : pathnode->path.parent = rel;
3463 1107 : 167389 : pathnode->path.pathtarget = rel->reltarget;
4888 1108 : 167389 : pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1109 : : required_outer);
1459 michael@paquier.xyz 1110 : 167389 : pathnode->path.parallel_aware = (parallel_degree > 0);
3470 tgl@sss.pgh.pa.us 1111 : 167389 : pathnode->path.parallel_safe = rel->consider_parallel;
3104 rhaas@postgresql.org 1112 : 167389 : pathnode->path.parallel_workers = parallel_degree;
2999 tgl@sss.pgh.pa.us 1113 : 167389 : pathnode->path.pathkeys = NIL; /* always unordered */
1114 : :
7445 1115 : 167389 : pathnode->bitmapqual = bitmapqual;
1116 : :
4888 1117 : 167389 : cost_bitmap_heap_scan(&pathnode->path, root, rel,
1118 : : pathnode->path.param_info,
1119 : : bitmapqual, loop_count);
1120 : :
7443 1121 : 167389 : return pathnode;
1122 : : }
1123 : :
1124 : : /*
1125 : : * create_bitmap_and_path
1126 : : * Creates a path node representing a BitmapAnd.
1127 : : */
1128 : : BitmapAndPath *
7398 1129 : 25025 : create_bitmap_and_path(PlannerInfo *root,
1130 : : RelOptInfo *rel,
1131 : : List *bitmapquals)
1132 : : {
7443 1133 : 25025 : BitmapAndPath *pathnode = makeNode(BitmapAndPath);
1880 1134 : 25025 : Relids required_outer = NULL;
1135 : : ListCell *lc;
1136 : :
7443 1137 : 25025 : pathnode->path.pathtype = T_BitmapAnd;
1138 : 25025 : pathnode->path.parent = rel;
3463 1139 : 25025 : pathnode->path.pathtarget = rel->reltarget;
1140 : :
1141 : : /*
1142 : : * Identify the required outer rels as the union of what the child paths
1143 : : * depend on. (Alternatively, we could insist that the caller pass this
1144 : : * in, but it's more convenient and reliable to compute it here.)
1145 : : */
1880 1146 [ + - + + : 75075 : foreach(lc, bitmapquals)
+ + ]
1147 : : {
1148 : 50050 : Path *bitmapqual = (Path *) lfirst(lc);
1149 : :
1150 : 50050 : required_outer = bms_add_members(required_outer,
1151 [ + + ]: 50050 : PATH_REQ_OUTER(bitmapqual));
1152 : : }
1153 : 25025 : pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1154 : : required_outer);
1155 : :
1156 : : /*
1157 : : * Currently, a BitmapHeapPath, BitmapAndPath, or BitmapOrPath will be
1158 : : * parallel-safe if and only if rel->consider_parallel is set. So, we can
1159 : : * set the flag for this path based only on the relation-level flag,
1160 : : * without actually iterating over the list of children.
1161 : : */
3587 rhaas@postgresql.org 1162 : 25025 : pathnode->path.parallel_aware = false;
3517 1163 : 25025 : pathnode->path.parallel_safe = rel->consider_parallel;
3376 1164 : 25025 : pathnode->path.parallel_workers = 0;
1165 : :
2999 tgl@sss.pgh.pa.us 1166 : 25025 : pathnode->path.pathkeys = NIL; /* always unordered */
1167 : :
7443 1168 : 25025 : pathnode->bitmapquals = bitmapquals;
1169 : :
1170 : : /* this sets bitmapselectivity as well as the regular cost fields: */
1171 : 25025 : cost_bitmap_and_node(pathnode, root);
1172 : :
1173 : 25025 : return pathnode;
1174 : : }
1175 : :
1176 : : /*
1177 : : * create_bitmap_or_path
1178 : : * Creates a path node representing a BitmapOr.
1179 : : */
1180 : : BitmapOrPath *
7398 1181 : 508 : create_bitmap_or_path(PlannerInfo *root,
1182 : : RelOptInfo *rel,
1183 : : List *bitmapquals)
1184 : : {
7443 1185 : 508 : BitmapOrPath *pathnode = makeNode(BitmapOrPath);
1880 1186 : 508 : Relids required_outer = NULL;
1187 : : ListCell *lc;
1188 : :
7443 1189 : 508 : pathnode->path.pathtype = T_BitmapOr;
1190 : 508 : pathnode->path.parent = rel;
3463 1191 : 508 : pathnode->path.pathtarget = rel->reltarget;
1192 : :
1193 : : /*
1194 : : * Identify the required outer rels as the union of what the child paths
1195 : : * depend on. (Alternatively, we could insist that the caller pass this
1196 : : * in, but it's more convenient and reliable to compute it here.)
1197 : : */
1880 1198 [ + - + + : 1425 : foreach(lc, bitmapquals)
+ + ]
1199 : : {
1200 : 917 : Path *bitmapqual = (Path *) lfirst(lc);
1201 : :
1202 : 917 : required_outer = bms_add_members(required_outer,
1203 [ + + ]: 917 : PATH_REQ_OUTER(bitmapqual));
1204 : : }
1205 : 508 : pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1206 : : required_outer);
1207 : :
1208 : : /*
1209 : : * Currently, a BitmapHeapPath, BitmapAndPath, or BitmapOrPath will be
1210 : : * parallel-safe if and only if rel->consider_parallel is set. So, we can
1211 : : * set the flag for this path based only on the relation-level flag,
1212 : : * without actually iterating over the list of children.
1213 : : */
3587 rhaas@postgresql.org 1214 : 508 : pathnode->path.parallel_aware = false;
3517 1215 : 508 : pathnode->path.parallel_safe = rel->consider_parallel;
3376 1216 : 508 : pathnode->path.parallel_workers = 0;
1217 : :
2999 tgl@sss.pgh.pa.us 1218 : 508 : pathnode->path.pathkeys = NIL; /* always unordered */
1219 : :
7443 1220 : 508 : pathnode->bitmapquals = bitmapquals;
1221 : :
1222 : : /* this sets bitmapselectivity as well as the regular cost fields: */
1223 : 508 : cost_bitmap_or_node(pathnode, root);
1224 : :
7445 1225 : 508 : return pathnode;
1226 : : }
1227 : :
1228 : : /*
1229 : : * create_tidscan_path
1230 : : * Creates a path corresponding to a scan by TID, returning the pathnode.
1231 : : */
1232 : : TidPath *
4759 1233 : 432 : create_tidscan_path(PlannerInfo *root, RelOptInfo *rel, List *tidquals,
1234 : : Relids required_outer)
1235 : : {
9278 bruce@momjian.us 1236 : 432 : TidPath *pathnode = makeNode(TidPath);
1237 : :
9419 1238 : 432 : pathnode->path.pathtype = T_TidScan;
1239 : 432 : pathnode->path.parent = rel;
3463 tgl@sss.pgh.pa.us 1240 : 432 : pathnode->path.pathtarget = rel->reltarget;
4759 1241 : 432 : pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1242 : : required_outer);
3587 rhaas@postgresql.org 1243 : 432 : pathnode->path.parallel_aware = false;
3517 1244 : 432 : pathnode->path.parallel_safe = rel->consider_parallel;
3376 1245 : 432 : pathnode->path.parallel_workers = 0;
2999 tgl@sss.pgh.pa.us 1246 : 432 : pathnode->path.pathkeys = NIL; /* always unordered */
1247 : :
7224 1248 : 432 : pathnode->tidquals = tidquals;
1249 : :
4759 1250 : 432 : cost_tidscan(&pathnode->path, root, rel, tidquals,
1251 : : pathnode->path.param_info);
1252 : :
9419 bruce@momjian.us 1253 : 432 : return pathnode;
1254 : : }
1255 : :
1256 : : /*
1257 : : * create_tidrangescan_path
1258 : : * Creates a path corresponding to a scan by a range of TIDs, returning
1259 : : * the pathnode.
1260 : : */
1261 : : TidRangePath *
1652 drowley@postgresql.o 1262 : 968 : create_tidrangescan_path(PlannerInfo *root, RelOptInfo *rel,
1263 : : List *tidrangequals, Relids required_outer)
1264 : : {
1265 : 968 : TidRangePath *pathnode = makeNode(TidRangePath);
1266 : :
1267 : 968 : pathnode->path.pathtype = T_TidRangeScan;
1268 : 968 : pathnode->path.parent = rel;
1269 : 968 : pathnode->path.pathtarget = rel->reltarget;
1270 : 968 : pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1271 : : required_outer);
1272 : 968 : pathnode->path.parallel_aware = false;
1273 : 968 : pathnode->path.parallel_safe = rel->consider_parallel;
1274 : 968 : pathnode->path.parallel_workers = 0;
1275 : 968 : pathnode->path.pathkeys = NIL; /* always unordered */
1276 : :
1277 : 968 : pathnode->tidrangequals = tidrangequals;
1278 : :
1279 : 968 : cost_tidrangescan(&pathnode->path, root, rel, tidrangequals,
1280 : : pathnode->path.param_info);
1281 : :
1282 : 968 : return pathnode;
1283 : : }
1284 : :
1285 : : /*
1286 : : * create_append_path
1287 : : * Creates a path corresponding to an Append plan, returning the
1288 : : * pathnode.
1289 : : *
1290 : : * Note that we must handle subpaths = NIL, representing a dummy access path.
1291 : : * Also, there are callers that pass root = NULL.
1292 : : *
1293 : : * 'rows', when passed as a non-negative number, will be used to overwrite the
1294 : : * returned path's row estimate. Otherwise, the row estimate is calculated
1295 : : * by totalling the row estimates from the 'subpaths' list.
1296 : : */
1297 : : AppendPath *
2709 alvherre@alvh.no-ip. 1298 : 38335 : create_append_path(PlannerInfo *root,
1299 : : RelOptInfo *rel,
1300 : : List *subpaths, List *partial_subpaths,
1301 : : List *pathkeys, Relids required_outer,
1302 : : int parallel_workers, bool parallel_aware,
1303 : : double rows)
1304 : : {
9064 tgl@sss.pgh.pa.us 1305 : 38335 : AppendPath *pathnode = makeNode(AppendPath);
1306 : : ListCell *l;
1307 : :
2832 rhaas@postgresql.org 1308 [ + + - + ]: 38335 : Assert(!parallel_aware || parallel_workers > 0);
1309 : :
9064 tgl@sss.pgh.pa.us 1310 : 38335 : pathnode->path.pathtype = T_Append;
1311 : 38335 : pathnode->path.parent = rel;
3463 1312 : 38335 : pathnode->path.pathtarget = rel->reltarget;
1313 : :
1314 : : /*
1315 : : * If this is for a baserel (not a join or non-leaf partition), we prefer
1316 : : * to apply get_baserel_parampathinfo to construct a full ParamPathInfo
1317 : : * for the path. This supports building a Memoize path atop this path,
1318 : : * and if this is a partitioned table the info may be useful for run-time
1319 : : * pruning (cf make_partition_pruneinfo()).
1320 : : *
1321 : : * However, if we don't have "root" then that won't work and we fall back
1322 : : * on the simpler get_appendrel_parampathinfo. There's no point in doing
1323 : : * the more expensive thing for a dummy path, either.
1324 : : */
905 1325 [ + + + + : 38335 : if (rel->reloptkind == RELOPT_BASEREL && root && subpaths != NIL)
+ + ]
2709 alvherre@alvh.no-ip. 1326 : 19109 : pathnode->path.param_info = get_baserel_parampathinfo(root,
1327 : : rel,
1328 : : required_outer);
1329 : : else
1330 : 19226 : pathnode->path.param_info = get_appendrel_parampathinfo(rel,
1331 : : required_outer);
1332 : :
2832 rhaas@postgresql.org 1333 : 38335 : pathnode->path.parallel_aware = parallel_aware;
3517 1334 : 38335 : pathnode->path.parallel_safe = rel->consider_parallel;
3376 1335 : 38335 : pathnode->path.parallel_workers = parallel_workers;
2346 tgl@sss.pgh.pa.us 1336 : 38335 : pathnode->path.pathkeys = pathkeys;
1337 : :
1338 : : /*
1339 : : * For parallel append, non-partial paths are sorted by descending total
1340 : : * costs. That way, the total time to finish all non-partial paths is
1341 : : * minimized. Also, the partial paths are sorted by descending startup
1342 : : * costs. There may be some paths that require to do startup work by a
1343 : : * single worker. In such case, it's better for workers to choose the
1344 : : * expensive ones first, whereas the leader should choose the cheapest
1345 : : * startup plan.
1346 : : */
2832 rhaas@postgresql.org 1347 [ + + ]: 38335 : if (pathnode->path.parallel_aware)
1348 : : {
1349 : : /*
1350 : : * We mustn't fiddle with the order of subpaths when the Append has
1351 : : * pathkeys. The order they're listed in is critical to keeping the
1352 : : * pathkeys valid.
1353 : : */
2346 tgl@sss.pgh.pa.us 1354 [ - + ]: 12866 : Assert(pathkeys == NIL);
1355 : :
2244 1356 : 12866 : list_sort(subpaths, append_total_cost_compare);
1357 : 12866 : list_sort(partial_subpaths, append_startup_cost_compare);
1358 : : }
2832 rhaas@postgresql.org 1359 : 38335 : pathnode->first_partial_path = list_length(subpaths);
1360 : 38335 : pathnode->subpaths = list_concat(subpaths, partial_subpaths);
1361 : :
1362 : : /*
1363 : : * Apply query-wide LIMIT if known and path is for sole base relation.
1364 : : * (Handling this at this low level is a bit klugy.)
1365 : : */
950 tgl@sss.pgh.pa.us 1366 [ + + + + ]: 38335 : if (root != NULL && bms_equal(rel->relids, root->all_query_rels))
2346 1367 : 19663 : pathnode->limit_tuples = root->limit_tuples;
1368 : : else
1369 : 18672 : pathnode->limit_tuples = -1.0;
1370 : :
2633 akapila@postgresql.o 1371 [ + + + + : 125561 : foreach(l, pathnode->subpaths)
+ + ]
1372 : : {
8934 bruce@momjian.us 1373 : 87226 : Path *subpath = (Path *) lfirst(l);
1374 : :
3517 rhaas@postgresql.org 1375 [ + + ]: 154679 : pathnode->path.parallel_safe = pathnode->path.parallel_safe &&
1376 [ + + ]: 67453 : subpath->parallel_safe;
1377 : :
1378 : : /* All child paths must have same parameterization */
4888 tgl@sss.pgh.pa.us 1379 [ + + - + ]: 87226 : Assert(bms_equal(PATH_REQ_OUTER(subpath), required_outer));
1380 : : }
1381 : :
2832 rhaas@postgresql.org 1382 [ + + - + ]: 38335 : Assert(!parallel_aware || pathnode->path.parallel_safe);
1383 : :
1384 : : /*
1385 : : * If there's exactly one child path then the output of the Append is
1386 : : * necessarily ordered the same as the child's, so we can inherit the
1387 : : * child's pathkeys if any, overriding whatever the caller might've said.
1388 : : * Furthermore, if the child's parallel awareness matches the Append's,
1389 : : * then the Append is a no-op and will be discarded later (in setrefs.c).
1390 : : * Then we can inherit the child's size and cost too, effectively charging
1391 : : * zero for the Append. Otherwise, we must do the normal costsize
1392 : : * calculation.
1393 : : */
2357 tgl@sss.pgh.pa.us 1394 [ + + ]: 38335 : if (list_length(pathnode->subpaths) == 1)
1395 : : {
1396 : 11144 : Path *child = (Path *) linitial(pathnode->subpaths);
1397 : :
1145 1398 [ + + ]: 11144 : if (child->parallel_aware == parallel_aware)
1399 : : {
1400 : 10925 : pathnode->path.rows = child->rows;
1401 : 10925 : pathnode->path.startup_cost = child->startup_cost;
1402 : 10925 : pathnode->path.total_cost = child->total_cost;
1403 : : }
1404 : : else
60 rguo@postgresql.org 1405 :GNC 219 : cost_append(pathnode, root);
1406 : : /* Must do this last, else cost_append complains */
2357 tgl@sss.pgh.pa.us 1407 :CBC 11144 : pathnode->path.pathkeys = child->pathkeys;
1408 : : }
1409 : : else
60 rguo@postgresql.org 1410 :GNC 27191 : cost_append(pathnode, root);
1411 : :
1412 : : /* If the caller provided a row estimate, override the computed value. */
2832 rhaas@postgresql.org 1413 [ + + ]:CBC 38335 : if (rows >= 0)
1414 : 288 : pathnode->path.rows = rows;
1415 : :
9064 tgl@sss.pgh.pa.us 1416 : 38335 : return pathnode;
1417 : : }
1418 : :
1419 : : /*
1420 : : * append_total_cost_compare
1421 : : * list_sort comparator for sorting append child paths
1422 : : * by total_cost descending
1423 : : *
1424 : : * For equal total costs, we fall back to comparing startup costs; if those
1425 : : * are equal too, break ties using bms_compare on the paths' relids.
1426 : : * (This is to avoid getting unpredictable results from list_sort.)
1427 : : */
1428 : : static int
2244 1429 : 2285 : append_total_cost_compare(const ListCell *a, const ListCell *b)
1430 : : {
1431 : 2285 : Path *path1 = (Path *) lfirst(a);
1432 : 2285 : Path *path2 = (Path *) lfirst(b);
1433 : : int cmp;
1434 : :
2797 1435 : 2285 : cmp = compare_path_costs(path1, path2, TOTAL_COST);
1436 [ + + ]: 2285 : if (cmp != 0)
1437 : 2147 : return -cmp;
1438 : 138 : return bms_compare(path1->parent->relids, path2->parent->relids);
1439 : : }
1440 : :
1441 : : /*
1442 : : * append_startup_cost_compare
1443 : : * list_sort comparator for sorting append child paths
1444 : : * by startup_cost descending
1445 : : *
1446 : : * For equal startup costs, we fall back to comparing total costs; if those
1447 : : * are equal too, break ties using bms_compare on the paths' relids.
1448 : : * (This is to avoid getting unpredictable results from list_sort.)
1449 : : */
1450 : : static int
2244 1451 : 17072 : append_startup_cost_compare(const ListCell *a, const ListCell *b)
1452 : : {
1453 : 17072 : Path *path1 = (Path *) lfirst(a);
1454 : 17072 : Path *path2 = (Path *) lfirst(b);
1455 : : int cmp;
1456 : :
2797 1457 : 17072 : cmp = compare_path_costs(path1, path2, STARTUP_COST);
1458 [ + + ]: 17072 : if (cmp != 0)
1459 : 6771 : return -cmp;
1460 : 10301 : return bms_compare(path1->parent->relids, path2->parent->relids);
1461 : : }
1462 : :
1463 : : /*
1464 : : * create_merge_append_path
1465 : : * Creates a path corresponding to a MergeAppend plan, returning the
1466 : : * pathnode.
1467 : : */
1468 : : MergeAppendPath *
5441 1469 : 2179 : create_merge_append_path(PlannerInfo *root,
1470 : : RelOptInfo *rel,
1471 : : List *subpaths,
1472 : : List *pathkeys,
1473 : : Relids required_outer)
1474 : : {
1475 : 2179 : MergeAppendPath *pathnode = makeNode(MergeAppendPath);
1476 : : int input_disabled_nodes;
1477 : : Cost input_startup_cost;
1478 : : Cost input_total_cost;
1479 : : ListCell *l;
1480 : :
1481 : : /*
1482 : : * We don't currently support parameterized MergeAppend paths, as
1483 : : * explained in the comments for generate_orderedappend_paths.
1484 : : */
404 rguo@postgresql.org 1485 [ + - - + ]: 2179 : Assert(bms_is_empty(rel->lateral_relids) && bms_is_empty(required_outer));
1486 : :
5441 tgl@sss.pgh.pa.us 1487 : 2179 : pathnode->path.pathtype = T_MergeAppend;
1488 : 2179 : pathnode->path.parent = rel;
3463 1489 : 2179 : pathnode->path.pathtarget = rel->reltarget;
404 rguo@postgresql.org 1490 : 2179 : pathnode->path.param_info = NULL;
3587 rhaas@postgresql.org 1491 : 2179 : pathnode->path.parallel_aware = false;
3517 1492 : 2179 : pathnode->path.parallel_safe = rel->consider_parallel;
3376 1493 : 2179 : pathnode->path.parallel_workers = 0;
5441 tgl@sss.pgh.pa.us 1494 : 2179 : pathnode->path.pathkeys = pathkeys;
1495 : 2179 : pathnode->subpaths = subpaths;
1496 : :
1497 : : /*
1498 : : * Apply query-wide LIMIT if known and path is for sole base relation.
1499 : : * (Handling this at this low level is a bit klugy.)
1500 : : */
950 1501 [ + + ]: 2179 : if (bms_equal(rel->relids, root->all_query_rels))
4888 1502 : 1101 : pathnode->limit_tuples = root->limit_tuples;
1503 : : else
1504 : 1078 : pathnode->limit_tuples = -1.0;
1505 : :
1506 : : /*
1507 : : * Add up the sizes and costs of the input paths.
1508 : : */
4971 1509 : 2179 : pathnode->path.rows = 0;
381 rhaas@postgresql.org 1510 : 2179 : input_disabled_nodes = 0;
5441 tgl@sss.pgh.pa.us 1511 : 2179 : input_startup_cost = 0;
1512 : 2179 : input_total_cost = 0;
1513 [ + - + + : 8130 : foreach(l, subpaths)
+ + ]
1514 : : {
1515 : 5951 : Path *subpath = (Path *) lfirst(l);
1516 : : int presorted_keys;
1517 : : Path sort_path; /* dummy for result of
1518 : : * cost_sort/cost_incremental_sort */
1519 : :
1520 : : /* All child paths should be unparameterized */
404 rguo@postgresql.org 1521 [ - + - - ]: 5951 : Assert(bms_is_empty(PATH_REQ_OUTER(subpath)));
1522 : :
4971 tgl@sss.pgh.pa.us 1523 : 5951 : pathnode->path.rows += subpath->rows;
3517 rhaas@postgresql.org 1524 [ + + ]: 10507 : pathnode->path.parallel_safe = pathnode->path.parallel_safe &&
1525 [ + + ]: 4556 : subpath->parallel_safe;
1526 : :
60 rguo@postgresql.org 1527 [ + + ]:GNC 5951 : if (!pathkeys_count_contained_in(pathkeys, subpath->pathkeys,
1528 : : &presorted_keys))
1529 : : {
1530 : : /*
1531 : : * We'll need to insert a Sort node, so include costs for that. We
1532 : : * choose to use incremental sort if it is enabled and there are
1533 : : * presorted keys; otherwise we use full sort.
1534 : : *
1535 : : * We can use the parent's LIMIT if any, since we certainly won't
1536 : : * pull more than that many tuples from any child.
1537 : : */
1538 [ + - + + ]: 173 : if (enable_incremental_sort && presorted_keys > 0)
1539 : : {
1540 : 9 : cost_incremental_sort(&sort_path,
1541 : : root,
1542 : : pathkeys,
1543 : : presorted_keys,
1544 : : subpath->disabled_nodes,
1545 : : subpath->startup_cost,
1546 : : subpath->total_cost,
1547 : : subpath->rows,
1548 : 9 : subpath->pathtarget->width,
1549 : : 0.0,
1550 : : work_mem,
1551 : : pathnode->limit_tuples);
1552 : : }
1553 : : else
1554 : : {
1555 : 164 : cost_sort(&sort_path,
1556 : : root,
1557 : : pathkeys,
1558 : : subpath->disabled_nodes,
1559 : : subpath->total_cost,
1560 : : subpath->rows,
1561 : 164 : subpath->pathtarget->width,
1562 : : 0.0,
1563 : : work_mem,
1564 : : pathnode->limit_tuples);
1565 : : }
1566 : :
1567 : 173 : subpath = &sort_path;
1568 : : }
1569 : :
1570 : 5951 : input_disabled_nodes += subpath->disabled_nodes;
1571 : 5951 : input_startup_cost += subpath->startup_cost;
1572 : 5951 : input_total_cost += subpath->total_cost;
1573 : : }
1574 : :
1575 : : /*
1576 : : * Now we can compute total costs of the MergeAppend. If there's exactly
1577 : : * one child path and its parallel awareness matches that of the
1578 : : * MergeAppend, then the MergeAppend is a no-op and will be discarded
1579 : : * later (in setrefs.c); otherwise we do the normal cost calculation.
1580 : : */
1145 tgl@sss.pgh.pa.us 1581 [ + + ]:CBC 2179 : if (list_length(subpaths) == 1 &&
1582 : 55 : ((Path *) linitial(subpaths))->parallel_aware ==
1583 [ + - ]: 55 : pathnode->path.parallel_aware)
1584 : : {
381 rhaas@postgresql.org 1585 : 55 : pathnode->path.disabled_nodes = input_disabled_nodes;
2357 tgl@sss.pgh.pa.us 1586 : 55 : pathnode->path.startup_cost = input_startup_cost;
1587 : 55 : pathnode->path.total_cost = input_total_cost;
1588 : : }
1589 : : else
1590 : 2124 : cost_merge_append(&pathnode->path, root,
1591 : : pathkeys, list_length(subpaths),
1592 : : input_disabled_nodes,
1593 : : input_startup_cost, input_total_cost,
1594 : : pathnode->path.rows);
1595 : :
5441 1596 : 2179 : return pathnode;
1597 : : }
1598 : :
1599 : : /*
1600 : : * create_group_result_path
1601 : : * Creates a path representing a Result-and-nothing-else plan.
1602 : : *
1603 : : * This is only used for degenerate grouping cases, in which we know we
1604 : : * need to produce one result row, possibly filtered by a HAVING qual.
1605 : : */
1606 : : GroupResultPath *
2413 1607 : 94538 : create_group_result_path(PlannerInfo *root, RelOptInfo *rel,
1608 : : PathTarget *target, List *havingqual)
1609 : : {
1610 : 94538 : GroupResultPath *pathnode = makeNode(GroupResultPath);
1611 : :
8340 1612 : 94538 : pathnode->path.pathtype = T_Result;
3488 1613 : 94538 : pathnode->path.parent = rel;
3470 1614 : 94538 : pathnode->path.pathtarget = target;
4483 bruce@momjian.us 1615 : 94538 : pathnode->path.param_info = NULL; /* there are no other rels... */
3587 rhaas@postgresql.org 1616 : 94538 : pathnode->path.parallel_aware = false;
3517 1617 : 94538 : pathnode->path.parallel_safe = rel->consider_parallel;
3376 1618 : 94538 : pathnode->path.parallel_workers = 0;
7007 tgl@sss.pgh.pa.us 1619 : 94538 : pathnode->path.pathkeys = NIL;
2413 1620 : 94538 : pathnode->quals = havingqual;
1621 : :
1622 : : /*
1623 : : * We can't quite use cost_resultscan() because the quals we want to
1624 : : * account for are not baserestrict quals of the rel. Might as well just
1625 : : * hack it here.
1626 : : */
4971 1627 : 94538 : pathnode->path.rows = 1;
3470 1628 : 94538 : pathnode->path.startup_cost = target->cost.startup;
1629 : 94538 : pathnode->path.total_cost = target->cost.startup +
1630 : 94538 : cpu_tuple_cost + target->cost.per_tuple;
1631 : :
1632 : : /*
1633 : : * Add cost of qual, if any --- but we ignore its selectivity, since our
1634 : : * rowcount estimate should be 1 no matter what the qual is.
1635 : : */
2413 1636 [ + + ]: 94538 : if (havingqual)
1637 : : {
1638 : : QualCost qual_cost;
1639 : :
1640 : 324 : cost_qual_eval(&qual_cost, havingqual, root);
1641 : : /* havingqual is evaluated once at startup */
3469 1642 : 324 : pathnode->path.startup_cost += qual_cost.startup + qual_cost.per_tuple;
1643 : 324 : pathnode->path.total_cost += qual_cost.startup + qual_cost.per_tuple;
1644 : : }
1645 : :
8340 1646 : 94538 : return pathnode;
1647 : : }
1648 : :
1649 : : /*
1650 : : * create_material_path
1651 : : * Creates a path corresponding to a Material plan, returning the
1652 : : * pathnode.
1653 : : */
1654 : : MaterialPath *
8316 1655 : 254254 : create_material_path(RelOptInfo *rel, Path *subpath)
1656 : : {
1657 : 254254 : MaterialPath *pathnode = makeNode(MaterialPath);
1658 : :
4888 1659 [ - + ]: 254254 : Assert(subpath->parent == rel);
1660 : :
8316 1661 : 254254 : pathnode->path.pathtype = T_Material;
1662 : 254254 : pathnode->path.parent = rel;
3463 1663 : 254254 : pathnode->path.pathtarget = rel->reltarget;
4888 1664 : 254254 : pathnode->path.param_info = subpath->param_info;
3587 rhaas@postgresql.org 1665 : 254254 : pathnode->path.parallel_aware = false;
3470 tgl@sss.pgh.pa.us 1666 [ + + ]: 480870 : pathnode->path.parallel_safe = rel->consider_parallel &&
1667 [ + + ]: 226616 : subpath->parallel_safe;
3376 rhaas@postgresql.org 1668 : 254254 : pathnode->path.parallel_workers = subpath->parallel_workers;
8316 tgl@sss.pgh.pa.us 1669 : 254254 : pathnode->path.pathkeys = subpath->pathkeys;
1670 : :
1671 : 254254 : pathnode->subpath = subpath;
1672 : :
1673 : 254254 : cost_material(&pathnode->path,
1674 : : subpath->disabled_nodes,
1675 : : subpath->startup_cost,
1676 : : subpath->total_cost,
1677 : : subpath->rows,
3488 1678 : 254254 : subpath->pathtarget->width);
1679 : :
8316 1680 : 254254 : return pathnode;
1681 : : }
1682 : :
1683 : : /*
1684 : : * create_memoize_path
1685 : : * Creates a path corresponding to a Memoize plan, returning the pathnode.
1686 : : */
1687 : : MemoizePath *
1515 drowley@postgresql.o 1688 : 146902 : create_memoize_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath,
1689 : : List *param_exprs, List *hash_operators,
1690 : : bool singlerow, bool binary_mode, Cardinality est_calls)
1691 : : {
1692 : 146902 : MemoizePath *pathnode = makeNode(MemoizePath);
1693 : :
1618 1694 [ - + ]: 146902 : Assert(subpath->parent == rel);
1695 : :
1515 1696 : 146902 : pathnode->path.pathtype = T_Memoize;
1618 1697 : 146902 : pathnode->path.parent = rel;
1698 : 146902 : pathnode->path.pathtarget = rel->reltarget;
1699 : 146902 : pathnode->path.param_info = subpath->param_info;
1700 : 146902 : pathnode->path.parallel_aware = false;
1701 [ + + ]: 286841 : pathnode->path.parallel_safe = rel->consider_parallel &&
1702 [ + + ]: 139939 : subpath->parallel_safe;
1703 : 146902 : pathnode->path.parallel_workers = subpath->parallel_workers;
1704 : 146902 : pathnode->path.pathkeys = subpath->pathkeys;
1705 : :
1706 : 146902 : pathnode->subpath = subpath;
1707 : 146902 : pathnode->hash_operators = hash_operators;
1708 : 146902 : pathnode->param_exprs = param_exprs;
1709 : 146902 : pathnode->singlerow = singlerow;
1382 1710 : 146902 : pathnode->binary_mode = binary_mode;
1711 : :
1712 : : /*
1713 : : * For now we set est_entries to 0. cost_memoize_rescan() does all the
1714 : : * hard work to determine how many cache entries there are likely to be,
1715 : : * so it seems best to leave it up to that function to fill this field in.
1716 : : * If left at 0, the executor will make a guess at a good value.
1717 : : */
1618 1718 : 146902 : pathnode->est_entries = 0;
1719 : :
39 drowley@postgresql.o 1720 :GNC 146902 : pathnode->est_calls = clamp_row_est(est_calls);
1721 : :
1722 : : /* These will also be set later in cost_memoize_rescan() */
1723 : 146902 : pathnode->est_unique_keys = 0.0;
1724 : 146902 : pathnode->est_hit_ratio = 0.0;
1725 : :
1726 : : /* we should not generate this path type when enable_memoize=false */
381 rhaas@postgresql.org 1727 [ - + ]:CBC 146902 : Assert(enable_memoize);
1728 : 146902 : pathnode->path.disabled_nodes = subpath->disabled_nodes;
1729 : :
1730 : : /*
1731 : : * Add a small additional charge for caching the first entry. All the
1732 : : * harder calculations for rescans are performed in cost_memoize_rescan().
1733 : : */
1618 drowley@postgresql.o 1734 : 146902 : pathnode->path.startup_cost = subpath->startup_cost + cpu_tuple_cost;
1735 : 146902 : pathnode->path.total_cost = subpath->total_cost + cpu_tuple_cost;
1736 : 146902 : pathnode->path.rows = subpath->rows;
1737 : :
1738 : 146902 : return pathnode;
1739 : : }
1740 : :
1741 : : /*
1742 : : * create_gather_merge_path
1743 : : *
1744 : : * Creates a path corresponding to a gather merge scan, returning
1745 : : * the pathnode.
1746 : : */
1747 : : GatherMergePath *
3103 rhaas@postgresql.org 1748 : 7110 : create_gather_merge_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath,
1749 : : PathTarget *target, List *pathkeys,
1750 : : Relids required_outer, double *rows)
1751 : : {
1752 : 7110 : GatherMergePath *pathnode = makeNode(GatherMergePath);
381 1753 : 7110 : int input_disabled_nodes = 0;
3034 bruce@momjian.us 1754 : 7110 : Cost input_startup_cost = 0;
1755 : 7110 : Cost input_total_cost = 0;
1756 : :
3103 rhaas@postgresql.org 1757 [ - + ]: 7110 : Assert(subpath->parallel_safe);
1758 [ - + ]: 7110 : Assert(pathkeys);
1759 : :
1760 : : /*
1761 : : * The subpath should guarantee that it is adequately ordered either by
1762 : : * adding an explicit sort node or by using presorted input. We cannot
1763 : : * add an explicit Sort node for the subpath in createplan.c on additional
1764 : : * pathkeys, because we can't guarantee the sort would be safe. For
1765 : : * example, expressions may be volatile or otherwise parallel unsafe.
1766 : : */
410 rguo@postgresql.org 1767 [ - + ]: 7110 : if (!pathkeys_contained_in(pathkeys, subpath->pathkeys))
410 rguo@postgresql.org 1768 [ # # ]:UBC 0 : elog(ERROR, "gather merge input not sufficiently sorted");
1769 : :
3103 rhaas@postgresql.org 1770 :CBC 7110 : pathnode->path.pathtype = T_GatherMerge;
1771 : 7110 : pathnode->path.parent = rel;
1772 : 7110 : pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1773 : : required_outer);
1774 : 7110 : pathnode->path.parallel_aware = false;
1775 : :
1776 : 7110 : pathnode->subpath = subpath;
1777 : 7110 : pathnode->num_workers = subpath->parallel_workers;
1778 : 7110 : pathnode->path.pathkeys = pathkeys;
1779 [ - + ]: 7110 : pathnode->path.pathtarget = target ? target : rel->reltarget;
1780 : :
381 1781 : 7110 : input_disabled_nodes += subpath->disabled_nodes;
410 rguo@postgresql.org 1782 : 7110 : input_startup_cost += subpath->startup_cost;
1783 : 7110 : input_total_cost += subpath->total_cost;
1784 : :
3103 rhaas@postgresql.org 1785 : 7110 : cost_gather_merge(pathnode, root, rel, pathnode->path.param_info,
1786 : : input_disabled_nodes, input_startup_cost,
1787 : : input_total_cost, rows);
1788 : :
1789 : 7110 : return pathnode;
1790 : : }
1791 : :
1792 : : /*
1793 : : * create_gather_path
1794 : : * Creates a path corresponding to a gather scan, returning the
1795 : : * pathnode.
1796 : : *
1797 : : * 'rows' may optionally be set to override row estimates from other sources.
1798 : : */
1799 : : GatherPath *
3629 1800 : 11422 : create_gather_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath,
1801 : : PathTarget *target, Relids required_outer, double *rows)
1802 : : {
1803 : 11422 : GatherPath *pathnode = makeNode(GatherPath);
1804 : :
3517 1805 [ - + ]: 11422 : Assert(subpath->parallel_safe);
1806 : :
3629 1807 : 11422 : pathnode->path.pathtype = T_Gather;
1808 : 11422 : pathnode->path.parent = rel;
3456 1809 : 11422 : pathnode->path.pathtarget = target;
3629 1810 : 11422 : pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1811 : : required_outer);
3587 1812 : 11422 : pathnode->path.parallel_aware = false;
3517 1813 : 11422 : pathnode->path.parallel_safe = false;
3081 1814 : 11422 : pathnode->path.parallel_workers = 0;
2999 tgl@sss.pgh.pa.us 1815 : 11422 : pathnode->path.pathkeys = NIL; /* Gather has unordered result */
1816 : :
3629 rhaas@postgresql.org 1817 : 11422 : pathnode->subpath = subpath;
3081 1818 : 11422 : pathnode->num_workers = subpath->parallel_workers;
3517 1819 : 11422 : pathnode->single_copy = false;
1820 : :
3081 1821 [ - + ]: 11422 : if (pathnode->num_workers == 0)
1822 : : {
3517 rhaas@postgresql.org 1823 :UBC 0 : pathnode->path.pathkeys = subpath->pathkeys;
3081 1824 : 0 : pathnode->num_workers = 1;
3517 1825 : 0 : pathnode->single_copy = true;
1826 : : }
1827 : :
3456 rhaas@postgresql.org 1828 :CBC 11422 : cost_gather(pathnode, root, rel, pathnode->path.param_info, rows);
1829 : :
3629 1830 : 11422 : return pathnode;
1831 : : }
1832 : :
1833 : : /*
1834 : : * create_subqueryscan_path
1835 : : * Creates a path corresponding to a scan of a subquery,
1836 : : * returning the pathnode.
1837 : : *
1838 : : * Caller must pass trivial_pathtarget = true if it believes rel->reltarget to
1839 : : * be trivial, ie just a fetch of all the subquery output columns in order.
1840 : : * While we could determine that here, the caller can usually do it more
1841 : : * efficiently (or at least amortize it over multiple calls).
1842 : : */
1843 : : SubqueryScanPath *
3470 tgl@sss.pgh.pa.us 1844 : 24276 : create_subqueryscan_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath,
1845 : : bool trivial_pathtarget,
1846 : : List *pathkeys, Relids required_outer)
1847 : : {
1848 : 24276 : SubqueryScanPath *pathnode = makeNode(SubqueryScanPath);
1849 : :
1850 : 24276 : pathnode->path.pathtype = T_SubqueryScan;
1851 : 24276 : pathnode->path.parent = rel;
3463 1852 : 24276 : pathnode->path.pathtarget = rel->reltarget;
3470 1853 : 24276 : pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1854 : : required_outer);
1855 : 24276 : pathnode->path.parallel_aware = false;
1856 [ + + ]: 40892 : pathnode->path.parallel_safe = rel->consider_parallel &&
1857 [ + + ]: 16616 : subpath->parallel_safe;
3376 rhaas@postgresql.org 1858 : 24276 : pathnode->path.parallel_workers = subpath->parallel_workers;
3470 tgl@sss.pgh.pa.us 1859 : 24276 : pathnode->path.pathkeys = pathkeys;
1860 : 24276 : pathnode->subpath = subpath;
1861 : :
1145 1862 : 24276 : cost_subqueryscan(pathnode, root, rel, pathnode->path.param_info,
1863 : : trivial_pathtarget);
1864 : :
9108 1865 : 24276 : return pathnode;
1866 : : }
1867 : :
1868 : : /*
1869 : : * create_functionscan_path
1870 : : * Creates a path corresponding to a sequential scan of a function,
1871 : : * returning the pathnode.
1872 : : */
1873 : : Path *
4778 1874 : 24317 : create_functionscan_path(PlannerInfo *root, RelOptInfo *rel,
1875 : : List *pathkeys, Relids required_outer)
1876 : : {
8518 1877 : 24317 : Path *pathnode = makeNode(Path);
1878 : :
1879 : 24317 : pathnode->pathtype = T_FunctionScan;
1880 : 24317 : pathnode->parent = rel;
3463 1881 : 24317 : pathnode->pathtarget = rel->reltarget;
4778 1882 : 24317 : pathnode->param_info = get_baserel_parampathinfo(root, rel,
1883 : : required_outer);
3587 rhaas@postgresql.org 1884 : 24317 : pathnode->parallel_aware = false;
3517 1885 : 24317 : pathnode->parallel_safe = rel->consider_parallel;
3376 1886 : 24317 : pathnode->parallel_workers = 0;
4307 tgl@sss.pgh.pa.us 1887 : 24317 : pathnode->pathkeys = pathkeys;
1888 : :
4778 1889 : 24317 : cost_functionscan(pathnode, root, rel, pathnode->param_info);
1890 : :
3104 alvherre@alvh.no-ip. 1891 : 24317 : return pathnode;
1892 : : }
1893 : :
1894 : : /*
1895 : : * create_tablefuncscan_path
1896 : : * Creates a path corresponding to a sequential scan of a table function,
1897 : : * returning the pathnode.
1898 : : */
1899 : : Path *
1900 : 311 : create_tablefuncscan_path(PlannerInfo *root, RelOptInfo *rel,
1901 : : Relids required_outer)
1902 : : {
1903 : 311 : Path *pathnode = makeNode(Path);
1904 : :
1905 : 311 : pathnode->pathtype = T_TableFuncScan;
1906 : 311 : pathnode->parent = rel;
1907 : 311 : pathnode->pathtarget = rel->reltarget;
1908 : 311 : pathnode->param_info = get_baserel_parampathinfo(root, rel,
1909 : : required_outer);
1910 : 311 : pathnode->parallel_aware = false;
1911 : 311 : pathnode->parallel_safe = rel->consider_parallel;
1912 : 311 : pathnode->parallel_workers = 0;
1913 : 311 : pathnode->pathkeys = NIL; /* result is always unordered */
1914 : :
1915 : 311 : cost_tablefuncscan(pathnode, root, rel, pathnode->param_info);
1916 : :
8518 tgl@sss.pgh.pa.us 1917 : 311 : return pathnode;
1918 : : }
1919 : :
1920 : : /*
1921 : : * create_valuesscan_path
1922 : : * Creates a path corresponding to a scan of a VALUES list,
1923 : : * returning the pathnode.
1924 : : */
1925 : : Path *
4773 1926 : 4104 : create_valuesscan_path(PlannerInfo *root, RelOptInfo *rel,
1927 : : Relids required_outer)
1928 : : {
6975 mail@joeconway.com 1929 : 4104 : Path *pathnode = makeNode(Path);
1930 : :
1931 : 4104 : pathnode->pathtype = T_ValuesScan;
1932 : 4104 : pathnode->parent = rel;
3463 tgl@sss.pgh.pa.us 1933 : 4104 : pathnode->pathtarget = rel->reltarget;
4773 1934 : 4104 : pathnode->param_info = get_baserel_parampathinfo(root, rel,
1935 : : required_outer);
3587 rhaas@postgresql.org 1936 : 4104 : pathnode->parallel_aware = false;
3517 1937 : 4104 : pathnode->parallel_safe = rel->consider_parallel;
3376 1938 : 4104 : pathnode->parallel_workers = 0;
6975 mail@joeconway.com 1939 : 4104 : pathnode->pathkeys = NIL; /* result is always unordered */
1940 : :
4773 tgl@sss.pgh.pa.us 1941 : 4104 : cost_valuesscan(pathnode, root, rel, pathnode->param_info);
1942 : :
6975 mail@joeconway.com 1943 : 4104 : return pathnode;
1944 : : }
1945 : :
1946 : : /*
1947 : : * create_ctescan_path
1948 : : * Creates a path corresponding to a scan of a non-self-reference CTE,
1949 : : * returning the pathnode.
1950 : : */
1951 : : Path *
529 tgl@sss.pgh.pa.us 1952 : 2120 : create_ctescan_path(PlannerInfo *root, RelOptInfo *rel,
1953 : : List *pathkeys, Relids required_outer)
1954 : : {
6181 1955 : 2120 : Path *pathnode = makeNode(Path);
1956 : :
1957 : 2120 : pathnode->pathtype = T_CteScan;
1958 : 2120 : pathnode->parent = rel;
3463 1959 : 2120 : pathnode->pathtarget = rel->reltarget;
4759 1960 : 2120 : pathnode->param_info = get_baserel_parampathinfo(root, rel,
1961 : : required_outer);
3587 rhaas@postgresql.org 1962 : 2120 : pathnode->parallel_aware = false;
3517 1963 : 2120 : pathnode->parallel_safe = rel->consider_parallel;
3376 1964 : 2120 : pathnode->parallel_workers = 0;
529 tgl@sss.pgh.pa.us 1965 : 2120 : pathnode->pathkeys = pathkeys;
1966 : :
4759 1967 : 2120 : cost_ctescan(pathnode, root, rel, pathnode->param_info);
1968 : :
6181 1969 : 2120 : return pathnode;
1970 : : }
1971 : :
1972 : : /*
1973 : : * create_namedtuplestorescan_path
1974 : : * Creates a path corresponding to a scan of a named tuplestore, returning
1975 : : * the pathnode.
1976 : : */
1977 : : Path *
3081 kgrittn@postgresql.o 1978 : 242 : create_namedtuplestorescan_path(PlannerInfo *root, RelOptInfo *rel,
1979 : : Relids required_outer)
1980 : : {
1981 : 242 : Path *pathnode = makeNode(Path);
1982 : :
1983 : 242 : pathnode->pathtype = T_NamedTuplestoreScan;
1984 : 242 : pathnode->parent = rel;
1985 : 242 : pathnode->pathtarget = rel->reltarget;
1986 : 242 : pathnode->param_info = get_baserel_parampathinfo(root, rel,
1987 : : required_outer);
1988 : 242 : pathnode->parallel_aware = false;
1989 : 242 : pathnode->parallel_safe = rel->consider_parallel;
1990 : 242 : pathnode->parallel_workers = 0;
1991 : 242 : pathnode->pathkeys = NIL; /* result is always unordered */
1992 : :
1993 : 242 : cost_namedtuplestorescan(pathnode, root, rel, pathnode->param_info);
1994 : :
1995 : 242 : return pathnode;
1996 : : }
1997 : :
1998 : : /*
1999 : : * create_resultscan_path
2000 : : * Creates a path corresponding to a scan of an RTE_RESULT relation,
2001 : : * returning the pathnode.
2002 : : */
2003 : : Path *
2413 tgl@sss.pgh.pa.us 2004 : 2134 : create_resultscan_path(PlannerInfo *root, RelOptInfo *rel,
2005 : : Relids required_outer)
2006 : : {
2007 : 2134 : Path *pathnode = makeNode(Path);
2008 : :
2009 : 2134 : pathnode->pathtype = T_Result;
2010 : 2134 : pathnode->parent = rel;
2011 : 2134 : pathnode->pathtarget = rel->reltarget;
2012 : 2134 : pathnode->param_info = get_baserel_parampathinfo(root, rel,
2013 : : required_outer);
2014 : 2134 : pathnode->parallel_aware = false;
2015 : 2134 : pathnode->parallel_safe = rel->consider_parallel;
2016 : 2134 : pathnode->parallel_workers = 0;
2017 : 2134 : pathnode->pathkeys = NIL; /* result is always unordered */
2018 : :
2019 : 2134 : cost_resultscan(pathnode, root, rel, pathnode->param_info);
2020 : :
2021 : 2134 : return pathnode;
2022 : : }
2023 : :
2024 : : /*
2025 : : * create_worktablescan_path
2026 : : * Creates a path corresponding to a scan of a self-reference CTE,
2027 : : * returning the pathnode.
2028 : : */
2029 : : Path *
4759 2030 : 466 : create_worktablescan_path(PlannerInfo *root, RelOptInfo *rel,
2031 : : Relids required_outer)
2032 : : {
6181 2033 : 466 : Path *pathnode = makeNode(Path);
2034 : :
2035 : 466 : pathnode->pathtype = T_WorkTableScan;
2036 : 466 : pathnode->parent = rel;
3463 2037 : 466 : pathnode->pathtarget = rel->reltarget;
4759 2038 : 466 : pathnode->param_info = get_baserel_parampathinfo(root, rel,
2039 : : required_outer);
3587 rhaas@postgresql.org 2040 : 466 : pathnode->parallel_aware = false;
3517 2041 : 466 : pathnode->parallel_safe = rel->consider_parallel;
3376 2042 : 466 : pathnode->parallel_workers = 0;
6181 tgl@sss.pgh.pa.us 2043 : 466 : pathnode->pathkeys = NIL; /* result is always unordered */
2044 : :
2045 : : /* Cost is the same as for a regular CTE scan */
4759 2046 : 466 : cost_ctescan(pathnode, root, rel, pathnode->param_info);
2047 : :
6181 2048 : 466 : return pathnode;
2049 : : }
2050 : :
2051 : : /*
2052 : : * create_foreignscan_path
2053 : : * Creates a path corresponding to a scan of a foreign base table,
2054 : : * returning the pathnode.
2055 : : *
2056 : : * This function is never called from core Postgres; rather, it's expected
2057 : : * to be called by the GetForeignPaths function of a foreign data wrapper.
2058 : : * We make the FDW supply all fields of the path, since we do not have any way
2059 : : * to calculate them in core. However, there is a usually-sane default for
2060 : : * the pathtarget (rel->reltarget), so we let a NULL for "target" select that.
2061 : : */
2062 : : ForeignPath *
4933 2063 : 1838 : create_foreignscan_path(PlannerInfo *root, RelOptInfo *rel,
2064 : : PathTarget *target,
2065 : : double rows, int disabled_nodes,
2066 : : Cost startup_cost, Cost total_cost,
2067 : : List *pathkeys,
2068 : : Relids required_outer,
2069 : : Path *fdw_outerpath,
2070 : : List *fdw_restrictinfo,
2071 : : List *fdw_private)
2072 : : {
5312 2073 : 1838 : ForeignPath *pathnode = makeNode(ForeignPath);
2074 : :
2075 : : /* Historically some FDWs were confused about when to use this */
2403 2076 [ + + - + ]: 1838 : Assert(IS_SIMPLE_REL(rel));
2077 : :
5312 2078 : 1838 : pathnode->path.pathtype = T_ForeignScan;
2079 : 1838 : pathnode->path.parent = rel;
3463 2080 [ + - ]: 1838 : pathnode->path.pathtarget = target ? target : rel->reltarget;
4888 2081 : 1838 : pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
2082 : : required_outer);
3587 rhaas@postgresql.org 2083 : 1838 : pathnode->path.parallel_aware = false;
3517 2084 : 1838 : pathnode->path.parallel_safe = rel->consider_parallel;
2403 tgl@sss.pgh.pa.us 2085 : 1838 : pathnode->path.parallel_workers = 0;
2086 : 1838 : pathnode->path.rows = rows;
381 rhaas@postgresql.org 2087 : 1838 : pathnode->path.disabled_nodes = disabled_nodes;
2403 tgl@sss.pgh.pa.us 2088 : 1838 : pathnode->path.startup_cost = startup_cost;
2089 : 1838 : pathnode->path.total_cost = total_cost;
2090 : 1838 : pathnode->path.pathkeys = pathkeys;
2091 : :
2092 : 1838 : pathnode->fdw_outerpath = fdw_outerpath;
753 efujita@postgresql.o 2093 : 1838 : pathnode->fdw_restrictinfo = fdw_restrictinfo;
2403 tgl@sss.pgh.pa.us 2094 : 1838 : pathnode->fdw_private = fdw_private;
2095 : :
2096 : 1838 : return pathnode;
2097 : : }
2098 : :
2099 : : /*
2100 : : * create_foreign_join_path
2101 : : * Creates a path corresponding to a scan of a foreign join,
2102 : : * returning the pathnode.
2103 : : *
2104 : : * This function is never called from core Postgres; rather, it's expected
2105 : : * to be called by the GetForeignJoinPaths function of a foreign data wrapper.
2106 : : * We make the FDW supply all fields of the path, since we do not have any way
2107 : : * to calculate them in core. However, there is a usually-sane default for
2108 : : * the pathtarget (rel->reltarget), so we let a NULL for "target" select that.
2109 : : */
2110 : : ForeignPath *
2111 : 600 : create_foreign_join_path(PlannerInfo *root, RelOptInfo *rel,
2112 : : PathTarget *target,
2113 : : double rows, int disabled_nodes,
2114 : : Cost startup_cost, Cost total_cost,
2115 : : List *pathkeys,
2116 : : Relids required_outer,
2117 : : Path *fdw_outerpath,
2118 : : List *fdw_restrictinfo,
2119 : : List *fdw_private)
2120 : : {
2121 : 600 : ForeignPath *pathnode = makeNode(ForeignPath);
2122 : :
2123 : : /*
2124 : : * We should use get_joinrel_parampathinfo to handle parameterized paths,
2125 : : * but the API of this function doesn't support it, and existing
2126 : : * extensions aren't yet trying to build such paths anyway. For the
2127 : : * moment just throw an error if someone tries it; eventually we should
2128 : : * revisit this.
2129 : : */
2130 [ + - - + ]: 600 : if (!bms_is_empty(required_outer) || !bms_is_empty(rel->lateral_relids))
2403 tgl@sss.pgh.pa.us 2131 [ # # ]:UBC 0 : elog(ERROR, "parameterized foreign joins are not supported yet");
2132 : :
2403 tgl@sss.pgh.pa.us 2133 :CBC 600 : pathnode->path.pathtype = T_ForeignScan;
2134 : 600 : pathnode->path.parent = rel;
2135 [ + - ]: 600 : pathnode->path.pathtarget = target ? target : rel->reltarget;
2136 : 600 : pathnode->path.param_info = NULL; /* XXX see above */
2137 : 600 : pathnode->path.parallel_aware = false;
2138 : 600 : pathnode->path.parallel_safe = rel->consider_parallel;
2139 : 600 : pathnode->path.parallel_workers = 0;
2140 : 600 : pathnode->path.rows = rows;
381 rhaas@postgresql.org 2141 : 600 : pathnode->path.disabled_nodes = disabled_nodes;
2403 tgl@sss.pgh.pa.us 2142 : 600 : pathnode->path.startup_cost = startup_cost;
2143 : 600 : pathnode->path.total_cost = total_cost;
2144 : 600 : pathnode->path.pathkeys = pathkeys;
2145 : :
2146 : 600 : pathnode->fdw_outerpath = fdw_outerpath;
753 efujita@postgresql.o 2147 : 600 : pathnode->fdw_restrictinfo = fdw_restrictinfo;
2403 tgl@sss.pgh.pa.us 2148 : 600 : pathnode->fdw_private = fdw_private;
2149 : :
2150 : 600 : return pathnode;
2151 : : }
2152 : :
2153 : : /*
2154 : : * create_foreign_upper_path
2155 : : * Creates a path corresponding to an upper relation that's computed
2156 : : * directly by an FDW, returning the pathnode.
2157 : : *
2158 : : * This function is never called from core Postgres; rather, it's expected to
2159 : : * be called by the GetForeignUpperPaths function of a foreign data wrapper.
2160 : : * We make the FDW supply all fields of the path, since we do not have any way
2161 : : * to calculate them in core. However, there is a usually-sane default for
2162 : : * the pathtarget (rel->reltarget), so we let a NULL for "target" select that.
2163 : : */
2164 : : ForeignPath *
2165 : 294 : create_foreign_upper_path(PlannerInfo *root, RelOptInfo *rel,
2166 : : PathTarget *target,
2167 : : double rows, int disabled_nodes,
2168 : : Cost startup_cost, Cost total_cost,
2169 : : List *pathkeys,
2170 : : Path *fdw_outerpath,
2171 : : List *fdw_restrictinfo,
2172 : : List *fdw_private)
2173 : : {
2174 : 294 : ForeignPath *pathnode = makeNode(ForeignPath);
2175 : :
2176 : : /*
2177 : : * Upper relations should never have any lateral references, since joining
2178 : : * is complete.
2179 : : */
2180 [ - + ]: 294 : Assert(bms_is_empty(rel->lateral_relids));
2181 : :
2182 : 294 : pathnode->path.pathtype = T_ForeignScan;
2183 : 294 : pathnode->path.parent = rel;
2184 [ - + ]: 294 : pathnode->path.pathtarget = target ? target : rel->reltarget;
2185 : 294 : pathnode->path.param_info = NULL;
2186 : 294 : pathnode->path.parallel_aware = false;
2187 : 294 : pathnode->path.parallel_safe = rel->consider_parallel;
3376 rhaas@postgresql.org 2188 : 294 : pathnode->path.parallel_workers = 0;
4933 tgl@sss.pgh.pa.us 2189 : 294 : pathnode->path.rows = rows;
381 rhaas@postgresql.org 2190 : 294 : pathnode->path.disabled_nodes = disabled_nodes;
4933 tgl@sss.pgh.pa.us 2191 : 294 : pathnode->path.startup_cost = startup_cost;
2192 : 294 : pathnode->path.total_cost = total_cost;
2193 : 294 : pathnode->path.pathkeys = pathkeys;
2194 : :
3560 rhaas@postgresql.org 2195 : 294 : pathnode->fdw_outerpath = fdw_outerpath;
753 efujita@postgresql.o 2196 : 294 : pathnode->fdw_restrictinfo = fdw_restrictinfo;
4933 tgl@sss.pgh.pa.us 2197 : 294 : pathnode->fdw_private = fdw_private;
2198 : :
5312 2199 : 294 : return pathnode;
2200 : : }
2201 : :
2202 : : /*
2203 : : * calc_nestloop_required_outer
2204 : : * Compute the required_outer set for a nestloop join path
2205 : : *
2206 : : * Note: when considering a child join, the inputs nonetheless use top-level
2207 : : * parent relids
2208 : : *
2209 : : * Note: result must not share storage with either input
2210 : : */
2211 : : Relids
2944 rhaas@postgresql.org 2212 : 1480599 : calc_nestloop_required_outer(Relids outerrelids,
2213 : : Relids outer_paramrels,
2214 : : Relids innerrelids,
2215 : : Relids inner_paramrels)
2216 : : {
2217 : : Relids required_outer;
2218 : :
2219 : : /* inner_path can require rels from outer path, but not vice versa */
2220 [ - + ]: 1480599 : Assert(!bms_overlap(outer_paramrels, innerrelids));
2221 : : /* easy case if inner path is not parameterized */
4888 tgl@sss.pgh.pa.us 2222 [ + + ]: 1480599 : if (!inner_paramrels)
2223 : 1003856 : return bms_copy(outer_paramrels);
2224 : : /* else, form the union ... */
2225 : 476743 : required_outer = bms_union(outer_paramrels, inner_paramrels);
2226 : : /* ... and remove any mention of now-satisfied outer rels */
4971 2227 : 476743 : required_outer = bms_del_members(required_outer,
2228 : : outerrelids);
2229 : 476743 : return required_outer;
2230 : : }
2231 : :
2232 : : /*
2233 : : * calc_non_nestloop_required_outer
2234 : : * Compute the required_outer set for a merge or hash join path
2235 : : *
2236 : : * Note: result must not share storage with either input
2237 : : */
2238 : : Relids
2239 : 968762 : calc_non_nestloop_required_outer(Path *outer_path, Path *inner_path)
2240 : : {
4836 bruce@momjian.us 2241 [ + + ]: 968762 : Relids outer_paramrels = PATH_REQ_OUTER(outer_path);
2242 [ + + ]: 968762 : Relids inner_paramrels = PATH_REQ_OUTER(inner_path);
2243 : : Relids innerrelids PG_USED_FOR_ASSERTS_ONLY;
2244 : : Relids outerrelids PG_USED_FOR_ASSERTS_ONLY;
2245 : : Relids required_outer;
2246 : :
2247 : : /*
2248 : : * Any parameterization of the input paths refers to topmost parents of
2249 : : * the relevant relations, because reparameterize_path_by_child() hasn't
2250 : : * been called yet. So we must consider topmost parents of the relations
2251 : : * being joined, too, while checking for disallowed parameterization
2252 : : * cases.
2253 : : */
605 tgl@sss.pgh.pa.us 2254 [ + + ]: 968762 : if (inner_path->parent->top_parent_relids)
2255 : 20155 : innerrelids = inner_path->parent->top_parent_relids;
2256 : : else
2257 : 948607 : innerrelids = inner_path->parent->relids;
2258 : :
2259 [ + + ]: 968762 : if (outer_path->parent->top_parent_relids)
2260 : 20155 : outerrelids = outer_path->parent->top_parent_relids;
2261 : : else
2262 : 948607 : outerrelids = outer_path->parent->relids;
2263 : :
2264 : : /* neither path can require rels from the other */
2265 [ - + ]: 968762 : Assert(!bms_overlap(outer_paramrels, innerrelids));
2266 [ - + ]: 968762 : Assert(!bms_overlap(inner_paramrels, outerrelids));
2267 : : /* form the union ... */
4888 2268 : 968762 : required_outer = bms_union(outer_paramrels, inner_paramrels);
2269 : : /* we do not need an explicit test for empty; bms_union gets it right */
4971 2270 : 968762 : return required_outer;
2271 : : }
2272 : :
2273 : : /*
2274 : : * create_nestloop_path
2275 : : * Creates a pathnode corresponding to a nestloop join between two
2276 : : * relations.
2277 : : *
2278 : : * 'joinrel' is the join relation.
2279 : : * 'jointype' is the type of join required
2280 : : * 'workspace' is the result from initial_cost_nestloop
2281 : : * 'extra' contains various information about the join
2282 : : * 'outer_path' is the outer path
2283 : : * 'inner_path' is the inner path
2284 : : * 'restrict_clauses' are the RestrictInfo nodes to apply at the join
2285 : : * 'pathkeys' are the path keys of the new join path
2286 : : * 'required_outer' is the set of required outer rels
2287 : : *
2288 : : * Returns the resulting path node.
2289 : : */
2290 : : NestPath *
7398 2291 : 666731 : create_nestloop_path(PlannerInfo *root,
2292 : : RelOptInfo *joinrel,
2293 : : JoinType jointype,
2294 : : JoinCostWorkspace *workspace,
2295 : : JoinPathExtraData *extra,
2296 : : Path *outer_path,
2297 : : Path *inner_path,
2298 : : List *restrict_clauses,
2299 : : List *pathkeys,
2300 : : Relids required_outer)
2301 : : {
9703 bruce@momjian.us 2302 : 666731 : NestPath *pathnode = makeNode(NestPath);
4888 tgl@sss.pgh.pa.us 2303 [ + + ]: 666731 : Relids inner_req_outer = PATH_REQ_OUTER(inner_path);
2304 : : Relids outerrelids;
2305 : :
2306 : : /*
2307 : : * Paths are parameterized by top-level parents, so run parameterization
2308 : : * tests on the parent relids.
2309 : : */
536 2310 [ + + ]: 666731 : if (outer_path->parent->top_parent_relids)
2311 : 10367 : outerrelids = outer_path->parent->top_parent_relids;
2312 : : else
2313 : 656364 : outerrelids = outer_path->parent->relids;
2314 : :
2315 : : /*
2316 : : * If the inner path is parameterized by the outer, we must drop any
2317 : : * restrict_clauses that are due to be moved into the inner path. We have
2318 : : * to do this now, rather than postpone the work till createplan time,
2319 : : * because the restrict_clauses list can affect the size and cost
2320 : : * estimates for this path. We detect such clauses by checking for serial
2321 : : * number match to clauses already enforced in the inner path.
2322 : : */
2323 [ + + ]: 666731 : if (bms_overlap(inner_req_outer, outerrelids))
2324 : : {
950 2325 : 187270 : Bitmapset *enforced_serials = get_param_path_clause_serials(inner_path);
4888 2326 : 187270 : List *jclauses = NIL;
2327 : : ListCell *lc;
2328 : :
2329 [ + + + + : 416728 : foreach(lc, restrict_clauses)
+ + ]
2330 : : {
2331 : 229458 : RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
2332 : :
950 2333 [ + + ]: 229458 : if (!bms_is_member(rinfo->rinfo_serial, enforced_serials))
4971 2334 : 30462 : jclauses = lappend(jclauses, rinfo);
2335 : : }
4888 2336 : 187270 : restrict_clauses = jclauses;
2337 : : }
2338 : :
1490 peter@eisentraut.org 2339 : 666731 : pathnode->jpath.path.pathtype = T_NestLoop;
2340 : 666731 : pathnode->jpath.path.parent = joinrel;
2341 : 666731 : pathnode->jpath.path.pathtarget = joinrel->reltarget;
2342 : 666731 : pathnode->jpath.path.param_info =
4888 tgl@sss.pgh.pa.us 2343 : 666731 : get_joinrel_parampathinfo(root,
2344 : : joinrel,
2345 : : outer_path,
2346 : : inner_path,
2347 : : extra->sjinfo,
2348 : : required_outer,
2349 : : &restrict_clauses);
1490 peter@eisentraut.org 2350 : 666731 : pathnode->jpath.path.parallel_aware = false;
2351 : 1937554 : pathnode->jpath.path.parallel_safe = joinrel->consider_parallel &&
3517 rhaas@postgresql.org 2352 [ + + + + : 666731 : outer_path->parallel_safe && inner_path->parallel_safe;
+ + ]
2353 : : /* This is a foolish way to estimate parallel_workers, but for now... */
1490 peter@eisentraut.org 2354 : 666731 : pathnode->jpath.path.parallel_workers = outer_path->parallel_workers;
2355 : 666731 : pathnode->jpath.path.pathkeys = pathkeys;
2356 : 666731 : pathnode->jpath.jointype = jointype;
2357 : 666731 : pathnode->jpath.inner_unique = extra->inner_unique;
2358 : 666731 : pathnode->jpath.outerjoinpath = outer_path;
2359 : 666731 : pathnode->jpath.innerjoinpath = inner_path;
2360 : 666731 : pathnode->jpath.joinrestrictinfo = restrict_clauses;
2361 : :
3074 tgl@sss.pgh.pa.us 2362 : 666731 : final_cost_nestloop(root, pathnode, workspace, extra);
2363 : :
9867 bruce@momjian.us 2364 : 666731 : return pathnode;
2365 : : }
2366 : :
2367 : : /*
2368 : : * create_mergejoin_path
2369 : : * Creates a pathnode corresponding to a mergejoin join between
2370 : : * two relations
2371 : : *
2372 : : * 'joinrel' is the join relation
2373 : : * 'jointype' is the type of join required
2374 : : * 'workspace' is the result from initial_cost_mergejoin
2375 : : * 'extra' contains various information about the join
2376 : : * 'outer_path' is the outer path
2377 : : * 'inner_path' is the inner path
2378 : : * 'restrict_clauses' are the RestrictInfo nodes to apply at the join
2379 : : * 'pathkeys' are the path keys of the new join path
2380 : : * 'required_outer' is the set of required outer rels
2381 : : * 'mergeclauses' are the RestrictInfo nodes to use as merge clauses
2382 : : * (this should be a subset of the restrict_clauses list)
2383 : : * 'outersortkeys' are the sort varkeys for the outer relation
2384 : : * 'innersortkeys' are the sort varkeys for the inner relation
2385 : : * 'outer_presorted_keys' is the number of presorted keys of the outer path
2386 : : */
2387 : : MergePath *
7398 tgl@sss.pgh.pa.us 2388 : 157964 : create_mergejoin_path(PlannerInfo *root,
2389 : : RelOptInfo *joinrel,
2390 : : JoinType jointype,
2391 : : JoinCostWorkspace *workspace,
2392 : : JoinPathExtraData *extra,
2393 : : Path *outer_path,
2394 : : Path *inner_path,
2395 : : List *restrict_clauses,
2396 : : List *pathkeys,
2397 : : Relids required_outer,
2398 : : List *mergeclauses,
2399 : : List *outersortkeys,
2400 : : List *innersortkeys,
2401 : : int outer_presorted_keys)
2402 : : {
10225 bruce@momjian.us 2403 : 157964 : MergePath *pathnode = makeNode(MergePath);
2404 : :
10226 2405 : 157964 : pathnode->jpath.path.pathtype = T_MergeJoin;
2406 : 157964 : pathnode->jpath.path.parent = joinrel;
3463 tgl@sss.pgh.pa.us 2407 : 157964 : pathnode->jpath.path.pathtarget = joinrel->reltarget;
4888 2408 : 157964 : pathnode->jpath.path.param_info =
2409 : 157964 : get_joinrel_parampathinfo(root,
2410 : : joinrel,
2411 : : outer_path,
2412 : : inner_path,
2413 : : extra->sjinfo,
2414 : : required_outer,
2415 : : &restrict_clauses);
3587 rhaas@postgresql.org 2416 : 157964 : pathnode->jpath.path.parallel_aware = false;
3517 2417 : 455918 : pathnode->jpath.path.parallel_safe = joinrel->consider_parallel &&
2418 [ + + + + : 157964 : outer_path->parallel_safe && inner_path->parallel_safe;
+ + ]
2419 : : /* This is a foolish way to estimate parallel_workers, but for now... */
3376 2420 : 157964 : pathnode->jpath.path.parallel_workers = outer_path->parallel_workers;
4971 tgl@sss.pgh.pa.us 2421 : 157964 : pathnode->jpath.path.pathkeys = pathkeys;
9125 2422 : 157964 : pathnode->jpath.jointype = jointype;
3074 2423 : 157964 : pathnode->jpath.inner_unique = extra->inner_unique;
10226 bruce@momjian.us 2424 : 157964 : pathnode->jpath.outerjoinpath = outer_path;
2425 : 157964 : pathnode->jpath.innerjoinpath = inner_path;
9343 tgl@sss.pgh.pa.us 2426 : 157964 : pathnode->jpath.joinrestrictinfo = restrict_clauses;
10226 bruce@momjian.us 2427 : 157964 : pathnode->path_mergeclauses = mergeclauses;
2428 : 157964 : pathnode->outersortkeys = outersortkeys;
2429 : 157964 : pathnode->innersortkeys = innersortkeys;
121 rguo@postgresql.org 2430 : 157964 : pathnode->outer_presorted_keys = outer_presorted_keys;
2431 : : /* pathnode->skip_mark_restore will be set by final_cost_mergejoin */
2432 : : /* pathnode->materialize_inner will be set by final_cost_mergejoin */
2433 : :
3074 tgl@sss.pgh.pa.us 2434 : 157964 : final_cost_mergejoin(root, pathnode, workspace, extra);
2435 : :
9867 bruce@momjian.us 2436 : 157964 : return pathnode;
2437 : : }
2438 : :
2439 : : /*
2440 : : * create_hashjoin_path
2441 : : * Creates a pathnode corresponding to a hash join between two relations.
2442 : : *
2443 : : * 'joinrel' is the join relation
2444 : : * 'jointype' is the type of join required
2445 : : * 'workspace' is the result from initial_cost_hashjoin
2446 : : * 'extra' contains various information about the join
2447 : : * 'outer_path' is the cheapest outer path
2448 : : * 'inner_path' is the cheapest inner path
2449 : : * 'parallel_hash' to select Parallel Hash of inner path (shared hash table)
2450 : : * 'restrict_clauses' are the RestrictInfo nodes to apply at the join
2451 : : * 'required_outer' is the set of required outer rels
2452 : : * 'hashclauses' are the RestrictInfo nodes to use as hash clauses
2453 : : * (this should be a subset of the restrict_clauses list)
2454 : : */
2455 : : HashPath *
7398 tgl@sss.pgh.pa.us 2456 : 141498 : create_hashjoin_path(PlannerInfo *root,
2457 : : RelOptInfo *joinrel,
2458 : : JoinType jointype,
2459 : : JoinCostWorkspace *workspace,
2460 : : JoinPathExtraData *extra,
2461 : : Path *outer_path,
2462 : : Path *inner_path,
2463 : : bool parallel_hash,
2464 : : List *restrict_clauses,
2465 : : Relids required_outer,
2466 : : List *hashclauses)
2467 : : {
10225 bruce@momjian.us 2468 : 141498 : HashPath *pathnode = makeNode(HashPath);
2469 : :
10226 2470 : 141498 : pathnode->jpath.path.pathtype = T_HashJoin;
2471 : 141498 : pathnode->jpath.path.parent = joinrel;
3463 tgl@sss.pgh.pa.us 2472 : 141498 : pathnode->jpath.path.pathtarget = joinrel->reltarget;
4888 2473 : 141498 : pathnode->jpath.path.param_info =
2474 : 141498 : get_joinrel_parampathinfo(root,
2475 : : joinrel,
2476 : : outer_path,
2477 : : inner_path,
2478 : : extra->sjinfo,
2479 : : required_outer,
2480 : : &restrict_clauses);
2817 andres@anarazel.de 2481 : 141498 : pathnode->jpath.path.parallel_aware =
2482 [ + + + + ]: 141498 : joinrel->consider_parallel && parallel_hash;
3517 rhaas@postgresql.org 2483 : 406918 : pathnode->jpath.path.parallel_safe = joinrel->consider_parallel &&
2484 [ + + + + : 141498 : outer_path->parallel_safe && inner_path->parallel_safe;
+ + ]
2485 : : /* This is a foolish way to estimate parallel_workers, but for now... */
3376 2486 : 141498 : pathnode->jpath.path.parallel_workers = outer_path->parallel_workers;
2487 : :
2488 : : /*
2489 : : * A hashjoin never has pathkeys, since its output ordering is
2490 : : * unpredictable due to possible batching. XXX If the inner relation is
2491 : : * small enough, we could instruct the executor that it must not batch,
2492 : : * and then we could assume that the output inherits the outer relation's
2493 : : * ordering, which might save a sort step. However there is considerable
2494 : : * downside if our estimate of the inner relation size is badly off. For
2495 : : * the moment we don't risk it. (Note also that if we wanted to take this
2496 : : * seriously, joinpath.c would have to consider many more paths for the
2497 : : * outer rel than it does now.)
2498 : : */
9518 tgl@sss.pgh.pa.us 2499 : 141498 : pathnode->jpath.path.pathkeys = NIL;
4971 2500 : 141498 : pathnode->jpath.jointype = jointype;
3074 2501 : 141498 : pathnode->jpath.inner_unique = extra->inner_unique;
4971 2502 : 141498 : pathnode->jpath.outerjoinpath = outer_path;
2503 : 141498 : pathnode->jpath.innerjoinpath = inner_path;
2504 : 141498 : pathnode->jpath.joinrestrictinfo = restrict_clauses;
10226 bruce@momjian.us 2505 : 141498 : pathnode->path_hashclauses = hashclauses;
2506 : : /* final_cost_hashjoin will fill in pathnode->num_batches */
2507 : :
3074 tgl@sss.pgh.pa.us 2508 : 141498 : final_cost_hashjoin(root, pathnode, workspace, extra);
2509 : :
9867 bruce@momjian.us 2510 : 141498 : return pathnode;
2511 : : }
2512 : :
2513 : : /*
2514 : : * create_projection_path
2515 : : * Creates a pathnode that represents performing a projection.
2516 : : *
2517 : : * 'rel' is the parent relation associated with the result
2518 : : * 'subpath' is the path representing the source of data
2519 : : * 'target' is the PathTarget to be computed
2520 : : */
2521 : : ProjectionPath *
3470 tgl@sss.pgh.pa.us 2522 : 198323 : create_projection_path(PlannerInfo *root,
2523 : : RelOptInfo *rel,
2524 : : Path *subpath,
2525 : : PathTarget *target)
2526 : : {
2527 : 198323 : ProjectionPath *pathnode = makeNode(ProjectionPath);
2528 : : PathTarget *oldtarget;
2529 : :
2530 : : /*
2531 : : * We mustn't put a ProjectionPath directly above another; it's useless
2532 : : * and will confuse create_projection_plan. Rather than making sure all
2533 : : * callers handle that, let's implement it here, by stripping off any
2534 : : * ProjectionPath in what we're given. Given this rule, there won't be
2535 : : * more than one.
2536 : : */
1559 2537 [ + + ]: 198323 : if (IsA(subpath, ProjectionPath))
2538 : : {
2539 : 6 : ProjectionPath *subpp = (ProjectionPath *) subpath;
2540 : :
2541 [ - + ]: 6 : Assert(subpp->path.parent == rel);
2542 : 6 : subpath = subpp->subpath;
2543 [ - + ]: 6 : Assert(!IsA(subpath, ProjectionPath));
2544 : : }
2545 : :
3470 2546 : 198323 : pathnode->path.pathtype = T_Result;
2547 : 198323 : pathnode->path.parent = rel;
2548 : 198323 : pathnode->path.pathtarget = target;
18 rguo@postgresql.org 2549 :GNC 198323 : pathnode->path.param_info = subpath->param_info;
3470 tgl@sss.pgh.pa.us 2550 :CBC 198323 : pathnode->path.parallel_aware = false;
2551 : 460266 : pathnode->path.parallel_safe = rel->consider_parallel &&
3354 rhaas@postgresql.org 2552 [ + + + + : 258019 : subpath->parallel_safe &&
+ - ]
3305 tgl@sss.pgh.pa.us 2553 : 59696 : is_parallel_safe(root, (Node *) target->exprs);
3376 rhaas@postgresql.org 2554 : 198323 : pathnode->path.parallel_workers = subpath->parallel_workers;
2555 : : /* Projection does not change the sort order */
3470 tgl@sss.pgh.pa.us 2556 : 198323 : pathnode->path.pathkeys = subpath->pathkeys;
2557 : :
2558 : 198323 : pathnode->subpath = subpath;
2559 : :
2560 : : /*
2561 : : * We might not need a separate Result node. If the input plan node type
2562 : : * can project, we can just tell it to project something else. Or, if it
2563 : : * can't project but the desired target has the same expression list as
2564 : : * what the input will produce anyway, we can still give it the desired
2565 : : * tlist (possibly changing its ressortgroupref labels, but nothing else).
2566 : : * Note: in the latter case, create_projection_plan has to recheck our
2567 : : * conclusion; see comments therein.
2568 : : */
1559 2569 : 198323 : oldtarget = subpath->pathtarget;
3364 2570 [ + + + + ]: 206179 : if (is_projection_capable_path(subpath) ||
2571 : 7856 : equal(oldtarget->exprs, target->exprs))
2572 : : {
2573 : : /* No separate Result node needed */
2574 : 191072 : pathnode->dummypp = true;
2575 : :
2576 : : /*
2577 : : * Set cost of plan as subpath's cost, adjusted for tlist replacement.
2578 : : */
2579 : 191072 : pathnode->path.rows = subpath->rows;
381 rhaas@postgresql.org 2580 : 191072 : pathnode->path.disabled_nodes = subpath->disabled_nodes;
3364 tgl@sss.pgh.pa.us 2581 : 191072 : pathnode->path.startup_cost = subpath->startup_cost +
2582 : 191072 : (target->cost.startup - oldtarget->cost.startup);
2583 : 191072 : pathnode->path.total_cost = subpath->total_cost +
2584 : 191072 : (target->cost.startup - oldtarget->cost.startup) +
2585 : 191072 : (target->cost.per_tuple - oldtarget->cost.per_tuple) * subpath->rows;
2586 : : }
2587 : : else
2588 : : {
2589 : : /* We really do need the Result node */
2590 : 7251 : pathnode->dummypp = false;
2591 : :
2592 : : /*
2593 : : * The Result node's cost is cpu_tuple_cost per row, plus the cost of
2594 : : * evaluating the tlist. There is no qual to worry about.
2595 : : */
2596 : 7251 : pathnode->path.rows = subpath->rows;
381 rhaas@postgresql.org 2597 : 7251 : pathnode->path.disabled_nodes = subpath->disabled_nodes;
3364 tgl@sss.pgh.pa.us 2598 : 7251 : pathnode->path.startup_cost = subpath->startup_cost +
2599 : 7251 : target->cost.startup;
2600 : 7251 : pathnode->path.total_cost = subpath->total_cost +
2601 : 7251 : target->cost.startup +
2602 : 7251 : (cpu_tuple_cost + target->cost.per_tuple) * subpath->rows;
2603 : : }
2604 : :
3470 2605 : 198323 : return pathnode;
2606 : : }
2607 : :
2608 : : /*
2609 : : * apply_projection_to_path
2610 : : * Add a projection step, or just apply the target directly to given path.
2611 : : *
2612 : : * This has the same net effect as create_projection_path(), except that if
2613 : : * a separate Result plan node isn't needed, we just replace the given path's
2614 : : * pathtarget with the desired one. This must be used only when the caller
2615 : : * knows that the given path isn't referenced elsewhere and so can be modified
2616 : : * in-place.
2617 : : *
2618 : : * If the input path is a GatherPath or GatherMergePath, we try to push the
2619 : : * new target down to its input as well; this is a yet more invasive
2620 : : * modification of the input path, which create_projection_path() can't do.
2621 : : *
2622 : : * Note that we mustn't change the source path's parent link; so when it is
2623 : : * add_path'd to "rel" things will be a bit inconsistent. So far that has
2624 : : * not caused any trouble.
2625 : : *
2626 : : * 'rel' is the parent relation associated with the result
2627 : : * 'path' is the path representing the source of data
2628 : : * 'target' is the PathTarget to be computed
2629 : : */
2630 : : Path *
2631 : 6796 : apply_projection_to_path(PlannerInfo *root,
2632 : : RelOptInfo *rel,
2633 : : Path *path,
2634 : : PathTarget *target)
2635 : : {
2636 : : QualCost oldcost;
2637 : :
2638 : : /*
2639 : : * If given path can't project, we might need a Result node, so make a
2640 : : * separate ProjectionPath.
2641 : : */
3364 2642 [ + + ]: 6796 : if (!is_projection_capable_path(path))
3470 2643 : 734 : return (Path *) create_projection_path(root, rel, path, target);
2644 : :
2645 : : /*
2646 : : * We can just jam the desired tlist into the existing path, being sure to
2647 : : * update its cost estimates appropriately.
2648 : : */
2649 : 6062 : oldcost = path->pathtarget->cost;
2650 : 6062 : path->pathtarget = target;
2651 : :
2652 : 6062 : path->startup_cost += target->cost.startup - oldcost.startup;
2653 : 6062 : path->total_cost += target->cost.startup - oldcost.startup +
2654 : 6062 : (target->cost.per_tuple - oldcost.per_tuple) * path->rows;
2655 : :
2656 : : /*
2657 : : * If the path happens to be a Gather or GatherMerge path, we'd like to
2658 : : * arrange for the subpath to return the required target list so that
2659 : : * workers can help project. But if there is something that is not
2660 : : * parallel-safe in the target expressions, then we can't.
2661 : : */
1939 2662 [ + - + + : 6074 : if ((IsA(path, GatherPath) || IsA(path, GatherMergePath)) &&
+ - ]
3305 2663 : 12 : is_parallel_safe(root, (Node *) target->exprs))
2664 : : {
2665 : : /*
2666 : : * We always use create_projection_path here, even if the subpath is
2667 : : * projection-capable, so as to avoid modifying the subpath in place.
2668 : : * It seems unlikely at present that there could be any other
2669 : : * references to the subpath, but better safe than sorry.
2670 : : *
2671 : : * Note that we don't change the parallel path's cost estimates; it
2672 : : * might be appropriate to do so, to reflect the fact that the bulk of
2673 : : * the target evaluation will happen in workers.
2674 : : */
2854 rhaas@postgresql.org 2675 [ - + ]: 12 : if (IsA(path, GatherPath))
2676 : : {
2854 rhaas@postgresql.org 2677 :UBC 0 : GatherPath *gpath = (GatherPath *) path;
2678 : :
2679 : 0 : gpath->subpath = (Path *)
2680 : 0 : create_projection_path(root,
2681 : 0 : gpath->subpath->parent,
2682 : : gpath->subpath,
2683 : : target);
2684 : : }
2685 : : else
2686 : : {
2854 rhaas@postgresql.org 2687 :CBC 12 : GatherMergePath *gmpath = (GatherMergePath *) path;
2688 : :
2689 : 12 : gmpath->subpath = (Path *)
2690 : 12 : create_projection_path(root,
2691 : 12 : gmpath->subpath->parent,
2692 : : gmpath->subpath,
2693 : : target);
2694 : : }
2695 : : }
3354 2696 [ + + ]: 6050 : else if (path->parallel_safe &&
3305 tgl@sss.pgh.pa.us 2697 [ + + ]: 2294 : !is_parallel_safe(root, (Node *) target->exprs))
2698 : : {
2699 : : /*
2700 : : * We're inserting a parallel-restricted target list into a path
2701 : : * currently marked parallel-safe, so we have to mark it as no longer
2702 : : * safe.
2703 : : */
3354 rhaas@postgresql.org 2704 : 6 : path->parallel_safe = false;
2705 : : }
2706 : :
3470 tgl@sss.pgh.pa.us 2707 : 6062 : return path;
2708 : : }
2709 : :
2710 : : /*
2711 : : * create_set_projection_path
2712 : : * Creates a pathnode that represents performing a projection that
2713 : : * includes set-returning functions.
2714 : : *
2715 : : * 'rel' is the parent relation associated with the result
2716 : : * 'subpath' is the path representing the source of data
2717 : : * 'target' is the PathTarget to be computed
2718 : : */
2719 : : ProjectSetPath *
3153 andres@anarazel.de 2720 : 5890 : create_set_projection_path(PlannerInfo *root,
2721 : : RelOptInfo *rel,
2722 : : Path *subpath,
2723 : : PathTarget *target)
2724 : : {
2725 : 5890 : ProjectSetPath *pathnode = makeNode(ProjectSetPath);
2726 : : double tlist_rows;
2727 : : ListCell *lc;
2728 : :
2729 : 5890 : pathnode->path.pathtype = T_ProjectSet;
2730 : 5890 : pathnode->path.parent = rel;
2731 : 5890 : pathnode->path.pathtarget = target;
2732 : : /* For now, assume we are above any joins, so no parameterization */
2733 : 5890 : pathnode->path.param_info = NULL;
2734 : 5890 : pathnode->path.parallel_aware = false;
2735 : 13990 : pathnode->path.parallel_safe = rel->consider_parallel &&
2736 [ + + + + : 8082 : subpath->parallel_safe &&
+ - ]
2737 : 2192 : is_parallel_safe(root, (Node *) target->exprs);
2738 : 5890 : pathnode->path.parallel_workers = subpath->parallel_workers;
2739 : : /* Projection does not change the sort order XXX? */
2740 : 5890 : pathnode->path.pathkeys = subpath->pathkeys;
2741 : :
2742 : 5890 : pathnode->subpath = subpath;
2743 : :
2744 : : /*
2745 : : * Estimate number of rows produced by SRFs for each row of input; if
2746 : : * there's more than one in this node, use the maximum.
2747 : : */
2748 : 5890 : tlist_rows = 1;
2749 [ + - + + : 12777 : foreach(lc, target->exprs)
+ + ]
2750 : : {
2751 : 6887 : Node *node = (Node *) lfirst(lc);
2752 : : double itemrows;
2753 : :
2401 tgl@sss.pgh.pa.us 2754 : 6887 : itemrows = expression_returns_set_rows(root, node);
3153 andres@anarazel.de 2755 [ + + ]: 6887 : if (tlist_rows < itemrows)
2756 : 5727 : tlist_rows = itemrows;
2757 : : }
2758 : :
2759 : : /*
2760 : : * In addition to the cost of evaluating the tlist, charge cpu_tuple_cost
2761 : : * per input row, and half of cpu_tuple_cost for each added output row.
2762 : : * This is slightly bizarre maybe, but it's what 9.6 did; we may revisit
2763 : : * this estimate later.
2764 : : */
381 rhaas@postgresql.org 2765 : 5890 : pathnode->path.disabled_nodes = subpath->disabled_nodes;
3153 andres@anarazel.de 2766 : 5890 : pathnode->path.rows = subpath->rows * tlist_rows;
2767 : 5890 : pathnode->path.startup_cost = subpath->startup_cost +
2768 : 5890 : target->cost.startup;
2769 : 5890 : pathnode->path.total_cost = subpath->total_cost +
2770 : 5890 : target->cost.startup +
2771 : 5890 : (cpu_tuple_cost + target->cost.per_tuple) * subpath->rows +
2772 : 5890 : (pathnode->path.rows - subpath->rows) * cpu_tuple_cost / 2;
2773 : :
2774 : 5890 : return pathnode;
2775 : : }
2776 : :
2777 : : /*
2778 : : * create_incremental_sort_path
2779 : : * Creates a pathnode that represents performing an incremental sort.
2780 : : *
2781 : : * 'rel' is the parent relation associated with the result
2782 : : * 'subpath' is the path representing the source of data
2783 : : * 'pathkeys' represents the desired sort order
2784 : : * 'presorted_keys' is the number of keys by which the input path is
2785 : : * already sorted
2786 : : * 'limit_tuples' is the estimated bound on the number of output tuples,
2787 : : * or -1 if no LIMIT or couldn't estimate
2788 : : */
2789 : : IncrementalSortPath *
1979 tomas.vondra@postgre 2790 : 4691 : create_incremental_sort_path(PlannerInfo *root,
2791 : : RelOptInfo *rel,
2792 : : Path *subpath,
2793 : : List *pathkeys,
2794 : : int presorted_keys,
2795 : : double limit_tuples)
2796 : : {
2797 : 4691 : IncrementalSortPath *sort = makeNode(IncrementalSortPath);
2798 : 4691 : SortPath *pathnode = &sort->spath;
2799 : :
2800 : 4691 : pathnode->path.pathtype = T_IncrementalSort;
2801 : 4691 : pathnode->path.parent = rel;
2802 : : /* Sort doesn't project, so use source path's pathtarget */
2803 : 4691 : pathnode->path.pathtarget = subpath->pathtarget;
18 rguo@postgresql.org 2804 :GNC 4691 : pathnode->path.param_info = subpath->param_info;
1979 tomas.vondra@postgre 2805 :CBC 4691 : pathnode->path.parallel_aware = false;
2806 [ + + ]: 7015 : pathnode->path.parallel_safe = rel->consider_parallel &&
2807 [ + + ]: 2324 : subpath->parallel_safe;
2808 : 4691 : pathnode->path.parallel_workers = subpath->parallel_workers;
2809 : 4691 : pathnode->path.pathkeys = pathkeys;
2810 : :
2811 : 4691 : pathnode->subpath = subpath;
2812 : :
2813 : 4691 : cost_incremental_sort(&pathnode->path,
2814 : : root, pathkeys, presorted_keys,
2815 : : subpath->disabled_nodes,
2816 : : subpath->startup_cost,
2817 : : subpath->total_cost,
2818 : : subpath->rows,
2819 : 4691 : subpath->pathtarget->width,
2820 : : 0.0, /* XXX comparison_cost shouldn't be 0? */
2821 : : work_mem, limit_tuples);
2822 : :
2823 : 4691 : sort->nPresortedCols = presorted_keys;
2824 : :
1741 tgl@sss.pgh.pa.us 2825 : 4691 : return sort;
2826 : : }
2827 : :
2828 : : /*
2829 : : * create_sort_path
2830 : : * Creates a pathnode that represents performing an explicit sort.
2831 : : *
2832 : : * 'rel' is the parent relation associated with the result
2833 : : * 'subpath' is the path representing the source of data
2834 : : * 'pathkeys' represents the desired sort order
2835 : : * 'limit_tuples' is the estimated bound on the number of output tuples,
2836 : : * or -1 if no LIMIT or couldn't estimate
2837 : : */
2838 : : SortPath *
3470 2839 : 54047 : create_sort_path(PlannerInfo *root,
2840 : : RelOptInfo *rel,
2841 : : Path *subpath,
2842 : : List *pathkeys,
2843 : : double limit_tuples)
2844 : : {
2845 : 54047 : SortPath *pathnode = makeNode(SortPath);
2846 : :
2847 : 54047 : pathnode->path.pathtype = T_Sort;
2848 : 54047 : pathnode->path.parent = rel;
2849 : : /* Sort doesn't project, so use source path's pathtarget */
2850 : 54047 : pathnode->path.pathtarget = subpath->pathtarget;
18 rguo@postgresql.org 2851 :GNC 54047 : pathnode->path.param_info = subpath->param_info;
3470 tgl@sss.pgh.pa.us 2852 :CBC 54047 : pathnode->path.parallel_aware = false;
2853 [ + + ]: 93787 : pathnode->path.parallel_safe = rel->consider_parallel &&
2854 [ + + ]: 39740 : subpath->parallel_safe;
3376 rhaas@postgresql.org 2855 : 54047 : pathnode->path.parallel_workers = subpath->parallel_workers;
3470 tgl@sss.pgh.pa.us 2856 : 54047 : pathnode->path.pathkeys = pathkeys;
2857 : :
2858 : 54047 : pathnode->subpath = subpath;
2859 : :
2860 : 54047 : cost_sort(&pathnode->path, root, pathkeys,
2861 : : subpath->disabled_nodes,
2862 : : subpath->total_cost,
2863 : : subpath->rows,
2864 : 54047 : subpath->pathtarget->width,
2865 : : 0.0, /* XXX comparison_cost shouldn't be 0? */
2866 : : work_mem, limit_tuples);
2867 : :
2868 : 54047 : return pathnode;
2869 : : }
2870 : :
2871 : : /*
2872 : : * create_group_path
2873 : : * Creates a pathnode that represents performing grouping of presorted input
2874 : : *
2875 : : * 'rel' is the parent relation associated with the result
2876 : : * 'subpath' is the path representing the source of data
2877 : : * 'target' is the PathTarget to be computed
2878 : : * 'groupClause' is a list of SortGroupClause's representing the grouping
2879 : : * 'qual' is the HAVING quals if any
2880 : : * 'numGroups' is the estimated number of groups
2881 : : */
2882 : : GroupPath *
2883 : 607 : create_group_path(PlannerInfo *root,
2884 : : RelOptInfo *rel,
2885 : : Path *subpath,
2886 : : List *groupClause,
2887 : : List *qual,
2888 : : double numGroups)
2889 : : {
2890 : 607 : GroupPath *pathnode = makeNode(GroupPath);
2727 rhaas@postgresql.org 2891 : 607 : PathTarget *target = rel->reltarget;
2892 : :
3470 tgl@sss.pgh.pa.us 2893 : 607 : pathnode->path.pathtype = T_Group;
2894 : 607 : pathnode->path.parent = rel;
2895 : 607 : pathnode->path.pathtarget = target;
2896 : : /* For now, assume we are above any joins, so no parameterization */
2897 : 607 : pathnode->path.param_info = NULL;
2898 : 607 : pathnode->path.parallel_aware = false;
2899 [ + + ]: 979 : pathnode->path.parallel_safe = rel->consider_parallel &&
2900 [ + + ]: 372 : subpath->parallel_safe;
3376 rhaas@postgresql.org 2901 : 607 : pathnode->path.parallel_workers = subpath->parallel_workers;
2902 : : /* Group doesn't change sort ordering */
3470 tgl@sss.pgh.pa.us 2903 : 607 : pathnode->path.pathkeys = subpath->pathkeys;
2904 : :
2905 : 607 : pathnode->subpath = subpath;
2906 : :
2907 : 607 : pathnode->groupClause = groupClause;
2908 : 607 : pathnode->qual = qual;
2909 : :
2910 : 607 : cost_group(&pathnode->path, root,
2911 : : list_length(groupClause),
2912 : : numGroups,
2913 : : qual,
2914 : : subpath->disabled_nodes,
2915 : : subpath->startup_cost, subpath->total_cost,
2916 : : subpath->rows);
2917 : :
2918 : : /* add tlist eval cost for each output row */
2919 : 607 : pathnode->path.startup_cost += target->cost.startup;
2920 : 607 : pathnode->path.total_cost += target->cost.startup +
2921 : 607 : target->cost.per_tuple * pathnode->path.rows;
2922 : :
2923 : 607 : return pathnode;
2924 : : }
2925 : :
2926 : : /*
2927 : : * create_unique_path
2928 : : * Creates a pathnode that represents performing an explicit Unique step
2929 : : * on presorted input.
2930 : : *
2931 : : * 'rel' is the parent relation associated with the result
2932 : : * 'subpath' is the path representing the source of data
2933 : : * 'numCols' is the number of grouping columns
2934 : : * 'numGroups' is the estimated number of groups
2935 : : *
2936 : : * The input path must be sorted on the grouping columns, plus possibly
2937 : : * additional columns; so the first numCols pathkeys are the grouping columns
2938 : : */
2939 : : UniquePath *
18 rguo@postgresql.org 2940 :GNC 10622 : create_unique_path(PlannerInfo *root,
2941 : : RelOptInfo *rel,
2942 : : Path *subpath,
2943 : : int numCols,
2944 : : double numGroups)
2945 : : {
2946 : 10622 : UniquePath *pathnode = makeNode(UniquePath);
2947 : :
3470 tgl@sss.pgh.pa.us 2948 :CBC 10622 : pathnode->path.pathtype = T_Unique;
2949 : 10622 : pathnode->path.parent = rel;
2950 : : /* Unique doesn't project, so use source path's pathtarget */
2951 : 10622 : pathnode->path.pathtarget = subpath->pathtarget;
18 rguo@postgresql.org 2952 :GNC 10622 : pathnode->path.param_info = subpath->param_info;
3470 tgl@sss.pgh.pa.us 2953 :CBC 10622 : pathnode->path.parallel_aware = false;
2954 [ + + ]: 19121 : pathnode->path.parallel_safe = rel->consider_parallel &&
2955 [ + + ]: 8499 : subpath->parallel_safe;
3376 rhaas@postgresql.org 2956 : 10622 : pathnode->path.parallel_workers = subpath->parallel_workers;
2957 : : /* Unique doesn't change the input ordering */
3470 tgl@sss.pgh.pa.us 2958 : 10622 : pathnode->path.pathkeys = subpath->pathkeys;
2959 : :
2960 : 10622 : pathnode->subpath = subpath;
2961 : 10622 : pathnode->numkeys = numCols;
2962 : :
2963 : : /*
2964 : : * Charge one cpu_operator_cost per comparison per input tuple. We assume
2965 : : * all columns get compared at most of the tuples. (XXX probably this is
2966 : : * an overestimate.)
2967 : : */
381 rhaas@postgresql.org 2968 : 10622 : pathnode->path.disabled_nodes = subpath->disabled_nodes;
3470 tgl@sss.pgh.pa.us 2969 : 10622 : pathnode->path.startup_cost = subpath->startup_cost;
2970 : 10622 : pathnode->path.total_cost = subpath->total_cost +
2971 : 10622 : cpu_operator_cost * subpath->rows * numCols;
2972 : 10622 : pathnode->path.rows = numGroups;
2973 : :
2974 : 10622 : return pathnode;
2975 : : }
2976 : :
2977 : : /*
2978 : : * create_agg_path
2979 : : * Creates a pathnode that represents performing aggregation/grouping
2980 : : *
2981 : : * 'rel' is the parent relation associated with the result
2982 : : * 'subpath' is the path representing the source of data
2983 : : * 'target' is the PathTarget to be computed
2984 : : * 'aggstrategy' is the Agg node's basic implementation strategy
2985 : : * 'aggsplit' is the Agg node's aggregate-splitting mode
2986 : : * 'groupClause' is a list of SortGroupClause's representing the grouping
2987 : : * 'qual' is the HAVING quals if any
2988 : : * 'aggcosts' contains cost info about the aggregate functions to be computed
2989 : : * 'numGroups' is the estimated number of groups (1 if not grouping)
2990 : : */
2991 : : AggPath *
2992 : 33844 : create_agg_path(PlannerInfo *root,
2993 : : RelOptInfo *rel,
2994 : : Path *subpath,
2995 : : PathTarget *target,
2996 : : AggStrategy aggstrategy,
2997 : : AggSplit aggsplit,
2998 : : List *groupClause,
2999 : : List *qual,
3000 : : const AggClauseCosts *aggcosts,
3001 : : double numGroups)
3002 : : {
3003 : 33844 : AggPath *pathnode = makeNode(AggPath);
3004 : :
3005 : 33844 : pathnode->path.pathtype = T_Agg;
3006 : 33844 : pathnode->path.parent = rel;
3007 : 33844 : pathnode->path.pathtarget = target;
18 rguo@postgresql.org 3008 :GNC 33844 : pathnode->path.param_info = subpath->param_info;
3470 tgl@sss.pgh.pa.us 3009 :CBC 33844 : pathnode->path.parallel_aware = false;
3010 [ + + ]: 58079 : pathnode->path.parallel_safe = rel->consider_parallel &&
3011 [ + + ]: 24235 : subpath->parallel_safe;
3376 rhaas@postgresql.org 3012 : 33844 : pathnode->path.parallel_workers = subpath->parallel_workers;
3013 : :
3470 tgl@sss.pgh.pa.us 3014 [ + + ]: 33844 : if (aggstrategy == AGG_SORTED)
3015 : : {
3016 : : /*
3017 : : * Attempt to preserve the order of the subpath. Additional pathkeys
3018 : : * may have been added in adjust_group_pathkeys_for_groupagg() to
3019 : : * support ORDER BY / DISTINCT aggregates. Pathkeys added there
3020 : : * belong to columns within the aggregate function, so we must strip
3021 : : * these additional pathkeys off as those columns are unavailable
3022 : : * above the aggregate node.
3023 : : */
698 drowley@postgresql.o 3024 [ + + ]: 3909 : if (list_length(subpath->pathkeys) > root->num_groupby_pathkeys)
3025 : 164 : pathnode->path.pathkeys = list_copy_head(subpath->pathkeys,
3026 : : root->num_groupby_pathkeys);
3027 : : else
3028 : 3745 : pathnode->path.pathkeys = subpath->pathkeys; /* preserves order */
3029 : : }
3030 : : else
3470 tgl@sss.pgh.pa.us 3031 : 29935 : pathnode->path.pathkeys = NIL; /* output is unordered */
3032 : :
3033 : 33844 : pathnode->subpath = subpath;
3034 : :
3035 : 33844 : pathnode->aggstrategy = aggstrategy;
3359 3036 : 33844 : pathnode->aggsplit = aggsplit;
3470 3037 : 33844 : pathnode->numGroups = numGroups;
2018 jdavis@postgresql.or 3038 [ + + ]: 33844 : pathnode->transitionSpace = aggcosts ? aggcosts->transitionSpace : 0;
3470 tgl@sss.pgh.pa.us 3039 : 33844 : pathnode->groupClause = groupClause;
3040 : 33844 : pathnode->qual = qual;
3041 : :
3042 : 33844 : cost_agg(&pathnode->path, root,
3043 : : aggstrategy, aggcosts,
3044 : : list_length(groupClause), numGroups,
3045 : : qual,
3046 : : subpath->disabled_nodes,
3047 : : subpath->startup_cost, subpath->total_cost,
1998 jdavis@postgresql.or 3048 : 33844 : subpath->rows, subpath->pathtarget->width);
3049 : :
3050 : : /* add tlist eval cost for each output row */
3470 tgl@sss.pgh.pa.us 3051 : 33844 : pathnode->path.startup_cost += target->cost.startup;
3052 : 33844 : pathnode->path.total_cost += target->cost.startup +
3053 : 33844 : target->cost.per_tuple * pathnode->path.rows;
3054 : :
3055 : 33844 : return pathnode;
3056 : : }
3057 : :
3058 : : /*
3059 : : * create_groupingsets_path
3060 : : * Creates a pathnode that represents performing GROUPING SETS aggregation
3061 : : *
3062 : : * GroupingSetsPath represents sorted grouping with one or more grouping sets.
3063 : : * The input path's result must be sorted to match the last entry in
3064 : : * rollup_groupclauses.
3065 : : *
3066 : : * 'rel' is the parent relation associated with the result
3067 : : * 'subpath' is the path representing the source of data
3068 : : * 'target' is the PathTarget to be computed
3069 : : * 'having_qual' is the HAVING quals if any
3070 : : * 'rollups' is a list of RollupData nodes
3071 : : * 'agg_costs' contains cost info about the aggregate functions to be computed
3072 : : */
3073 : : GroupingSetsPath *
3074 : 1064 : create_groupingsets_path(PlannerInfo *root,
3075 : : RelOptInfo *rel,
3076 : : Path *subpath,
3077 : : List *having_qual,
3078 : : AggStrategy aggstrategy,
3079 : : List *rollups,
3080 : : const AggClauseCosts *agg_costs)
3081 : : {
3082 : 1064 : GroupingSetsPath *pathnode = makeNode(GroupingSetsPath);
2727 rhaas@postgresql.org 3083 : 1064 : PathTarget *target = rel->reltarget;
3084 : : ListCell *lc;
3085 rhodiumtoad@postgres 3085 : 1064 : bool is_first = true;
3086 : 1064 : bool is_first_sort = true;
3087 : :
3088 : : /* The topmost generated Plan node will be an Agg */
3470 tgl@sss.pgh.pa.us 3089 : 1064 : pathnode->path.pathtype = T_Agg;
3090 : 1064 : pathnode->path.parent = rel;
3091 : 1064 : pathnode->path.pathtarget = target;
3092 : 1064 : pathnode->path.param_info = subpath->param_info;
3093 : 1064 : pathnode->path.parallel_aware = false;
3094 [ + + ]: 1559 : pathnode->path.parallel_safe = rel->consider_parallel &&
3095 [ + - ]: 495 : subpath->parallel_safe;
3376 rhaas@postgresql.org 3096 : 1064 : pathnode->path.parallel_workers = subpath->parallel_workers;
3470 tgl@sss.pgh.pa.us 3097 : 1064 : pathnode->subpath = subpath;
3098 : :
3099 : : /*
3100 : : * Simplify callers by downgrading AGG_SORTED to AGG_PLAIN, and AGG_MIXED
3101 : : * to AGG_HASHED, here if possible.
3102 : : */
3085 rhodiumtoad@postgres 3103 [ + + + + ]: 1518 : if (aggstrategy == AGG_SORTED &&
3104 : 454 : list_length(rollups) == 1 &&
3105 [ + + ]: 229 : ((RollupData *) linitial(rollups))->groupClause == NIL)
3106 : 21 : aggstrategy = AGG_PLAIN;
3107 : :
3108 [ + + - + ]: 1522 : if (aggstrategy == AGG_MIXED &&
3109 : 458 : list_length(rollups) == 1)
3085 rhodiumtoad@postgres 3110 :UBC 0 : aggstrategy = AGG_HASHED;
3111 : :
3112 : : /*
3113 : : * Output will be in sorted order by group_pathkeys if, and only if, there
3114 : : * is a single rollup operation on a non-empty list of grouping
3115 : : * expressions.
3116 : : */
3085 rhodiumtoad@postgres 3117 [ + + + + ]:CBC 1064 : if (aggstrategy == AGG_SORTED && list_length(rollups) == 1)
3470 tgl@sss.pgh.pa.us 3118 : 208 : pathnode->path.pathkeys = root->group_pathkeys;
3119 : : else
3120 : 856 : pathnode->path.pathkeys = NIL;
3121 : :
3085 rhodiumtoad@postgres 3122 : 1064 : pathnode->aggstrategy = aggstrategy;
3123 : 1064 : pathnode->rollups = rollups;
3470 tgl@sss.pgh.pa.us 3124 : 1064 : pathnode->qual = having_qual;
2018 jdavis@postgresql.or 3125 [ + - ]: 1064 : pathnode->transitionSpace = agg_costs ? agg_costs->transitionSpace : 0;
3126 : :
3085 rhodiumtoad@postgres 3127 [ - + ]: 1064 : Assert(rollups != NIL);
3128 [ + + - + ]: 1064 : Assert(aggstrategy != AGG_PLAIN || list_length(rollups) == 1);
3129 [ + + - + ]: 1064 : Assert(aggstrategy != AGG_MIXED || list_length(rollups) > 1);
3130 : :
3131 [ + - + + : 3708 : foreach(lc, rollups)
+ + ]
3132 : : {
3133 : 2644 : RollupData *rollup = lfirst(lc);
3134 : 2644 : List *gsets = rollup->gsets;
3135 : 2644 : int numGroupCols = list_length(linitial(gsets));
3136 : :
3137 : : /*
3138 : : * In AGG_SORTED or AGG_PLAIN mode, the first rollup takes the
3139 : : * (already-sorted) input, and following ones do their own sort.
3140 : : *
3141 : : * In AGG_HASHED mode, there is one rollup for each grouping set.
3142 : : *
3143 : : * In AGG_MIXED mode, the first rollups are hashed, the first
3144 : : * non-hashed one takes the (already-sorted) input, and following ones
3145 : : * do their own sort.
3146 : : */
3147 [ + + ]: 2644 : if (is_first)
3148 : : {
3149 : 1064 : cost_agg(&pathnode->path, root,
3150 : : aggstrategy,
3151 : : agg_costs,
3152 : : numGroupCols,
3153 : : rollup->numGroups,
3154 : : having_qual,
3155 : : subpath->disabled_nodes,
3156 : : subpath->startup_cost,
3157 : : subpath->total_cost,
3158 : : subpath->rows,
1998 jdavis@postgresql.or 3159 : 1064 : subpath->pathtarget->width);
3085 rhodiumtoad@postgres 3160 : 1064 : is_first = false;
3161 [ + + ]: 1064 : if (!rollup->is_hashed)
3162 : 454 : is_first_sort = false;
3163 : : }
3164 : : else
3165 : : {
3166 : : Path sort_path; /* dummy for result of cost_sort */
3167 : : Path agg_path; /* dummy for result of cost_agg */
3168 : :
3169 [ + + + + ]: 1580 : if (rollup->is_hashed || is_first_sort)
3170 : : {
3171 : : /*
3172 : : * Account for cost of aggregation, but don't charge input
3173 : : * cost again
3174 : : */
3175 : 1211 : cost_agg(&agg_path, root,
3176 : 1211 : rollup->is_hashed ? AGG_HASHED : AGG_SORTED,
3177 : : agg_costs,
3178 : : numGroupCols,
3179 : : rollup->numGroups,
3180 : : having_qual,
3181 : : 0, 0.0, 0.0,
3182 : : subpath->rows,
1998 jdavis@postgresql.or 3183 [ + + ]: 1211 : subpath->pathtarget->width);
3085 rhodiumtoad@postgres 3184 [ + + ]: 1211 : if (!rollup->is_hashed)
3185 : 458 : is_first_sort = false;
3186 : : }
3187 : : else
3188 : : {
3189 : : /* Account for cost of sort, but don't charge input cost again */
381 rhaas@postgresql.org 3190 : 369 : cost_sort(&sort_path, root, NIL, 0,
3191 : : 0.0,
3192 : : subpath->rows,
3085 rhodiumtoad@postgres 3193 : 369 : subpath->pathtarget->width,
3194 : : 0.0,
3195 : : work_mem,
3196 : : -1.0);
3197 : :
3198 : : /* Account for cost of aggregation */
3199 : :
3200 : 369 : cost_agg(&agg_path, root,
3201 : : AGG_SORTED,
3202 : : agg_costs,
3203 : : numGroupCols,
3204 : : rollup->numGroups,
3205 : : having_qual,
3206 : : sort_path.disabled_nodes,
3207 : : sort_path.startup_cost,
3208 : : sort_path.total_cost,
3209 : : sort_path.rows,
1998 jdavis@postgresql.or 3210 : 369 : subpath->pathtarget->width);
3211 : : }
3212 : :
381 rhaas@postgresql.org 3213 : 1580 : pathnode->path.disabled_nodes += agg_path.disabled_nodes;
3470 tgl@sss.pgh.pa.us 3214 : 1580 : pathnode->path.total_cost += agg_path.total_cost;
3215 : 1580 : pathnode->path.rows += agg_path.rows;
3216 : : }
3217 : : }
3218 : :
3219 : : /* add tlist eval cost for each output row */
3220 : 1064 : pathnode->path.startup_cost += target->cost.startup;
3221 : 1064 : pathnode->path.total_cost += target->cost.startup +
3222 : 1064 : target->cost.per_tuple * pathnode->path.rows;
3223 : :
3224 : 1064 : return pathnode;
3225 : : }
3226 : :
3227 : : /*
3228 : : * create_minmaxagg_path
3229 : : * Creates a pathnode that represents computation of MIN/MAX aggregates
3230 : : *
3231 : : * 'rel' is the parent relation associated with the result
3232 : : * 'target' is the PathTarget to be computed
3233 : : * 'mmaggregates' is a list of MinMaxAggInfo structs
3234 : : * 'quals' is the HAVING quals if any
3235 : : */
3236 : : MinMaxAggPath *
3237 : 205 : create_minmaxagg_path(PlannerInfo *root,
3238 : : RelOptInfo *rel,
3239 : : PathTarget *target,
3240 : : List *mmaggregates,
3241 : : List *quals)
3242 : : {
3243 : 205 : MinMaxAggPath *pathnode = makeNode(MinMaxAggPath);
3244 : : Cost initplan_cost;
381 rhaas@postgresql.org 3245 : 205 : int initplan_disabled_nodes = 0;
3246 : : ListCell *lc;
3247 : :
3248 : : /* The topmost generated Plan node will be a Result */
3470 tgl@sss.pgh.pa.us 3249 : 205 : pathnode->path.pathtype = T_Result;
3250 : 205 : pathnode->path.parent = rel;
3251 : 205 : pathnode->path.pathtarget = target;
3252 : : /* For now, assume we are above any joins, so no parameterization */
3253 : 205 : pathnode->path.param_info = NULL;
3254 : 205 : pathnode->path.parallel_aware = false;
786 3255 : 205 : pathnode->path.parallel_safe = true; /* might change below */
3376 rhaas@postgresql.org 3256 : 205 : pathnode->path.parallel_workers = 0;
3257 : : /* Result is one unordered row */
3470 tgl@sss.pgh.pa.us 3258 : 205 : pathnode->path.rows = 1;
3259 : 205 : pathnode->path.pathkeys = NIL;
3260 : :
3261 : 205 : pathnode->mmaggregates = mmaggregates;
3262 : 205 : pathnode->quals = quals;
3263 : :
3264 : : /* Calculate cost of all the initplans, and check parallel safety */
3265 : 205 : initplan_cost = 0;
3266 [ + - + + : 428 : foreach(lc, mmaggregates)
+ + ]
3267 : : {
3268 : 223 : MinMaxAggInfo *mminfo = (MinMaxAggInfo *) lfirst(lc);
3269 : :
381 rhaas@postgresql.org 3270 : 223 : initplan_disabled_nodes += mminfo->path->disabled_nodes;
3470 tgl@sss.pgh.pa.us 3271 : 223 : initplan_cost += mminfo->pathcost;
786 3272 [ + + ]: 223 : if (!mminfo->path->parallel_safe)
3273 : 55 : pathnode->path.parallel_safe = false;
3274 : : }
3275 : :
3276 : : /* add tlist eval cost for each output row, plus cpu_tuple_cost */
381 rhaas@postgresql.org 3277 : 205 : pathnode->path.disabled_nodes = initplan_disabled_nodes;
3470 tgl@sss.pgh.pa.us 3278 : 205 : pathnode->path.startup_cost = initplan_cost + target->cost.startup;
3279 : 205 : pathnode->path.total_cost = initplan_cost + target->cost.startup +
3280 : 205 : target->cost.per_tuple + cpu_tuple_cost;
3281 : :
3282 : : /*
3283 : : * Add cost of qual, if any --- but we ignore its selectivity, since our
3284 : : * rowcount estimate should be 1 no matter what the qual is.
3285 : : */
2865 3286 [ - + ]: 205 : if (quals)
3287 : : {
3288 : : QualCost qual_cost;
3289 : :
2865 tgl@sss.pgh.pa.us 3290 :UBC 0 : cost_qual_eval(&qual_cost, quals, root);
3291 : 0 : pathnode->path.startup_cost += qual_cost.startup;
3292 : 0 : pathnode->path.total_cost += qual_cost.startup + qual_cost.per_tuple;
3293 : : }
3294 : :
3295 : : /*
3296 : : * If the initplans were all parallel-safe, also check safety of the
3297 : : * target and quals. (The Result node itself isn't parallelizable, but if
3298 : : * we are in a subquery then it can be useful for the outer query to know
3299 : : * that this one is parallel-safe.)
3300 : : */
786 tgl@sss.pgh.pa.us 3301 [ + + ]:CBC 205 : if (pathnode->path.parallel_safe)
3302 : 150 : pathnode->path.parallel_safe =
3303 [ + - + - ]: 300 : is_parallel_safe(root, (Node *) target->exprs) &&
3304 : 150 : is_parallel_safe(root, (Node *) quals);
3305 : :
3470 3306 : 205 : return pathnode;
3307 : : }
3308 : :
3309 : : /*
3310 : : * create_windowagg_path
3311 : : * Creates a pathnode that represents computation of window functions
3312 : : *
3313 : : * 'rel' is the parent relation associated with the result
3314 : : * 'subpath' is the path representing the source of data
3315 : : * 'target' is the PathTarget to be computed
3316 : : * 'windowFuncs' is a list of WindowFunc structs
3317 : : * 'runCondition' is a list of OpExprs to short-circuit WindowAgg execution
3318 : : * 'winclause' is a WindowClause that is common to all the WindowFuncs
3319 : : * 'qual' WindowClause.runconditions from lower-level WindowAggPaths.
3320 : : * Must always be NIL when topwindow == false
3321 : : * 'topwindow' pass as true only for the top-level WindowAgg. False for all
3322 : : * intermediate WindowAggs.
3323 : : *
3324 : : * The input must be sorted according to the WindowClause's PARTITION keys
3325 : : * plus ORDER BY keys.
3326 : : */
3327 : : WindowAggPath *
3328 : 1377 : create_windowagg_path(PlannerInfo *root,
3329 : : RelOptInfo *rel,
3330 : : Path *subpath,
3331 : : PathTarget *target,
3332 : : List *windowFuncs,
3333 : : List *runCondition,
3334 : : WindowClause *winclause,
3335 : : List *qual,
3336 : : bool topwindow)
3337 : : {
3338 : 1377 : WindowAggPath *pathnode = makeNode(WindowAggPath);
3339 : :
3340 : : /* qual can only be set for the topwindow */
1247 drowley@postgresql.o 3341 [ + + - + ]: 1377 : Assert(qual == NIL || topwindow);
3342 : :
3470 tgl@sss.pgh.pa.us 3343 : 1377 : pathnode->path.pathtype = T_WindowAgg;
3344 : 1377 : pathnode->path.parent = rel;
3345 : 1377 : pathnode->path.pathtarget = target;
3346 : : /* For now, assume we are above any joins, so no parameterization */
3347 : 1377 : pathnode->path.param_info = NULL;
3348 : 1377 : pathnode->path.parallel_aware = false;
3349 [ - + ]: 1377 : pathnode->path.parallel_safe = rel->consider_parallel &&
3470 tgl@sss.pgh.pa.us 3350 [ # # ]:UBC 0 : subpath->parallel_safe;
3376 rhaas@postgresql.org 3351 :CBC 1377 : pathnode->path.parallel_workers = subpath->parallel_workers;
3352 : : /* WindowAgg preserves the input sort order */
3470 tgl@sss.pgh.pa.us 3353 : 1377 : pathnode->path.pathkeys = subpath->pathkeys;
3354 : :
3355 : 1377 : pathnode->subpath = subpath;
3356 : 1377 : pathnode->winclause = winclause;
1247 drowley@postgresql.o 3357 : 1377 : pathnode->qual = qual;
489 3358 : 1377 : pathnode->runCondition = runCondition;
1247 3359 : 1377 : pathnode->topwindow = topwindow;
3360 : :
3361 : : /*
3362 : : * For costing purposes, assume that there are no redundant partitioning
3363 : : * or ordering columns; it's not worth the trouble to deal with that
3364 : : * corner case here. So we just pass the unmodified list lengths to
3365 : : * cost_windowagg.
3366 : : */
3470 tgl@sss.pgh.pa.us 3367 : 1377 : cost_windowagg(&pathnode->path, root,
3368 : : windowFuncs,
3369 : : winclause,
3370 : : subpath->disabled_nodes,
3371 : : subpath->startup_cost,
3372 : : subpath->total_cost,
3373 : : subpath->rows);
3374 : :
3375 : : /* add tlist eval cost for each output row */
3376 : 1377 : pathnode->path.startup_cost += target->cost.startup;
3377 : 1377 : pathnode->path.total_cost += target->cost.startup +
3378 : 1377 : target->cost.per_tuple * pathnode->path.rows;
3379 : :
3380 : 1377 : return pathnode;
3381 : : }
3382 : :
3383 : : /*
3384 : : * create_setop_path
3385 : : * Creates a pathnode that represents computation of INTERSECT or EXCEPT
3386 : : *
3387 : : * 'rel' is the parent relation associated with the result
3388 : : * 'leftpath' is the path representing the left-hand source of data
3389 : : * 'rightpath' is the path representing the right-hand source of data
3390 : : * 'cmd' is the specific semantics (INTERSECT or EXCEPT, with/without ALL)
3391 : : * 'strategy' is the implementation strategy (sorted or hashed)
3392 : : * 'groupList' is a list of SortGroupClause's representing the grouping
3393 : : * 'numGroups' is the estimated number of distinct groups in left-hand input
3394 : : * 'outputRows' is the estimated number of output rows
3395 : : *
3396 : : * leftpath and rightpath must produce the same columns. Moreover, if
3397 : : * strategy is SETOP_SORTED, leftpath and rightpath must both be sorted
3398 : : * by all the grouping columns.
3399 : : */
3400 : : SetOpPath *
3401 : 632 : create_setop_path(PlannerInfo *root,
3402 : : RelOptInfo *rel,
3403 : : Path *leftpath,
3404 : : Path *rightpath,
3405 : : SetOpCmd cmd,
3406 : : SetOpStrategy strategy,
3407 : : List *groupList,
3408 : : double numGroups,
3409 : : double outputRows)
3410 : : {
3411 : 632 : SetOpPath *pathnode = makeNode(SetOpPath);
3412 : :
3413 : 632 : pathnode->path.pathtype = T_SetOp;
3414 : 632 : pathnode->path.parent = rel;
261 3415 : 632 : pathnode->path.pathtarget = rel->reltarget;
3416 : : /* For now, assume we are above any joins, so no parameterization */
3470 3417 : 632 : pathnode->path.param_info = NULL;
3418 : 632 : pathnode->path.parallel_aware = false;
3419 : 1264 : pathnode->path.parallel_safe = rel->consider_parallel &&
261 3420 [ - + - - : 632 : leftpath->parallel_safe && rightpath->parallel_safe;
- - ]
3421 : 632 : pathnode->path.parallel_workers =
3422 : 632 : leftpath->parallel_workers + rightpath->parallel_workers;
3423 : : /* SetOp preserves the input sort order if in sort mode */
3470 3424 : 632 : pathnode->path.pathkeys =
261 3425 [ + + ]: 632 : (strategy == SETOP_SORTED) ? leftpath->pathkeys : NIL;
3426 : :
3427 : 632 : pathnode->leftpath = leftpath;
3428 : 632 : pathnode->rightpath = rightpath;
3470 3429 : 632 : pathnode->cmd = cmd;
3430 : 632 : pathnode->strategy = strategy;
261 3431 : 632 : pathnode->groupList = groupList;
3470 3432 : 632 : pathnode->numGroups = numGroups;
3433 : :
3434 : : /*
3435 : : * Compute cost estimates. As things stand, we end up with the same total
3436 : : * cost in this node for sort and hash methods, but different startup
3437 : : * costs. This could be refined perhaps, but it'll do for now.
3438 : : */
261 3439 : 632 : pathnode->path.disabled_nodes =
3440 : 632 : leftpath->disabled_nodes + rightpath->disabled_nodes;
3441 [ + + ]: 632 : if (strategy == SETOP_SORTED)
3442 : : {
3443 : : /*
3444 : : * In sorted mode, we can emit output incrementally. Charge one
3445 : : * cpu_operator_cost per comparison per input tuple. Like cost_group,
3446 : : * we assume all columns get compared at most of the tuples.
3447 : : */
3448 : 331 : pathnode->path.startup_cost =
3449 : 331 : leftpath->startup_cost + rightpath->startup_cost;
3450 : 331 : pathnode->path.total_cost =
3451 : 662 : leftpath->total_cost + rightpath->total_cost +
3452 : 331 : cpu_operator_cost * (leftpath->rows + rightpath->rows) * list_length(groupList);
3453 : :
3454 : : /*
3455 : : * Also charge a small amount per extracted tuple. Like cost_sort,
3456 : : * charge only operator cost not cpu_tuple_cost, since SetOp does no
3457 : : * qual-checking or projection.
3458 : : */
3459 : 331 : pathnode->path.total_cost += cpu_operator_cost * outputRows;
3460 : : }
3461 : : else
3462 : : {
3463 : : Size hashentrysize;
3464 : :
3465 : : /*
3466 : : * In hashed mode, we must read all the input before we can emit
3467 : : * anything. Also charge comparison costs to represent the cost of
3468 : : * hash table lookups.
3469 : : */
3470 : 301 : pathnode->path.startup_cost =
3471 : 602 : leftpath->total_cost + rightpath->total_cost +
3472 : 301 : cpu_operator_cost * (leftpath->rows + rightpath->rows) * list_length(groupList);
3473 : 301 : pathnode->path.total_cost = pathnode->path.startup_cost;
3474 : :
3475 : : /*
3476 : : * Also charge a small amount per extracted tuple. Like cost_sort,
3477 : : * charge only operator cost not cpu_tuple_cost, since SetOp does no
3478 : : * qual-checking or projection.
3479 : : */
3480 : 301 : pathnode->path.total_cost += cpu_operator_cost * outputRows;
3481 : :
3482 : : /*
3483 : : * Mark the path as disabled if enable_hashagg is off. While this
3484 : : * isn't exactly a HashAgg node, it seems close enough to justify
3485 : : * letting that switch control it.
3486 : : */
3487 [ + + ]: 301 : if (!enable_hashagg)
3488 : 57 : pathnode->path.disabled_nodes++;
3489 : :
3490 : : /*
3491 : : * Also disable if it doesn't look like the hashtable will fit into
3492 : : * hash_mem.
3493 : : */
3494 : 301 : hashentrysize = MAXALIGN(leftpath->pathtarget->width) +
3495 : : MAXALIGN(SizeofMinimalTupleHeader);
3496 [ - + ]: 301 : if (hashentrysize * numGroups > get_hash_memory_limit())
261 tgl@sss.pgh.pa.us 3497 :UBC 0 : pathnode->path.disabled_nodes++;
3498 : : }
3470 tgl@sss.pgh.pa.us 3499 :CBC 632 : pathnode->path.rows = outputRows;
3500 : :
3501 : 632 : return pathnode;
3502 : : }
3503 : :
3504 : : /*
3505 : : * create_recursiveunion_path
3506 : : * Creates a pathnode that represents a recursive UNION node
3507 : : *
3508 : : * 'rel' is the parent relation associated with the result
3509 : : * 'leftpath' is the source of data for the non-recursive term
3510 : : * 'rightpath' is the source of data for the recursive term
3511 : : * 'target' is the PathTarget to be computed
3512 : : * 'distinctList' is a list of SortGroupClause's representing the grouping
3513 : : * 'wtParam' is the ID of Param representing work table
3514 : : * 'numGroups' is the estimated number of groups
3515 : : *
3516 : : * For recursive UNION ALL, distinctList is empty and numGroups is zero
3517 : : */
3518 : : RecursiveUnionPath *
3519 : 463 : create_recursiveunion_path(PlannerInfo *root,
3520 : : RelOptInfo *rel,
3521 : : Path *leftpath,
3522 : : Path *rightpath,
3523 : : PathTarget *target,
3524 : : List *distinctList,
3525 : : int wtParam,
3526 : : double numGroups)
3527 : : {
3528 : 463 : RecursiveUnionPath *pathnode = makeNode(RecursiveUnionPath);
3529 : :
3530 : 463 : pathnode->path.pathtype = T_RecursiveUnion;
3531 : 463 : pathnode->path.parent = rel;
3532 : 463 : pathnode->path.pathtarget = target;
3533 : : /* For now, assume we are above any joins, so no parameterization */
3534 : 463 : pathnode->path.param_info = NULL;
3535 : 463 : pathnode->path.parallel_aware = false;
3536 : 926 : pathnode->path.parallel_safe = rel->consider_parallel &&
3537 [ - + - - : 463 : leftpath->parallel_safe && rightpath->parallel_safe;
- - ]
3538 : : /* Foolish, but we'll do it like joins for now: */
3376 rhaas@postgresql.org 3539 : 463 : pathnode->path.parallel_workers = leftpath->parallel_workers;
3540 : : /* RecursiveUnion result is always unsorted */
3470 tgl@sss.pgh.pa.us 3541 : 463 : pathnode->path.pathkeys = NIL;
3542 : :
3543 : 463 : pathnode->leftpath = leftpath;
3544 : 463 : pathnode->rightpath = rightpath;
3545 : 463 : pathnode->distinctList = distinctList;
3546 : 463 : pathnode->wtParam = wtParam;
3547 : 463 : pathnode->numGroups = numGroups;
3548 : :
3549 : 463 : cost_recursive_union(&pathnode->path, leftpath, rightpath);
3550 : :
3551 : 463 : return pathnode;
3552 : : }
3553 : :
3554 : : /*
3555 : : * create_lockrows_path
3556 : : * Creates a pathnode that represents acquiring row locks
3557 : : *
3558 : : * 'rel' is the parent relation associated with the result
3559 : : * 'subpath' is the path representing the source of data
3560 : : * 'rowMarks' is a list of PlanRowMark's
3561 : : * 'epqParam' is the ID of Param for EvalPlanQual re-eval
3562 : : */
3563 : : LockRowsPath *
3564 : 4110 : create_lockrows_path(PlannerInfo *root, RelOptInfo *rel,
3565 : : Path *subpath, List *rowMarks, int epqParam)
3566 : : {
3567 : 4110 : LockRowsPath *pathnode = makeNode(LockRowsPath);
3568 : :
3569 : 4110 : pathnode->path.pathtype = T_LockRows;
3570 : 4110 : pathnode->path.parent = rel;
3571 : : /* LockRows doesn't project, so use source path's pathtarget */
3572 : 4110 : pathnode->path.pathtarget = subpath->pathtarget;
3573 : : /* For now, assume we are above any joins, so no parameterization */
3574 : 4110 : pathnode->path.param_info = NULL;
3575 : 4110 : pathnode->path.parallel_aware = false;
3576 : 4110 : pathnode->path.parallel_safe = false;
3376 rhaas@postgresql.org 3577 : 4110 : pathnode->path.parallel_workers = 0;
3470 tgl@sss.pgh.pa.us 3578 : 4110 : pathnode->path.rows = subpath->rows;
3579 : :
3580 : : /*
3581 : : * The result cannot be assumed sorted, since locking might cause the sort
3582 : : * key columns to be replaced with new values.
3583 : : */
3584 : 4110 : pathnode->path.pathkeys = NIL;
3585 : :
3586 : 4110 : pathnode->subpath = subpath;
3587 : 4110 : pathnode->rowMarks = rowMarks;
3588 : 4110 : pathnode->epqParam = epqParam;
3589 : :
3590 : : /*
3591 : : * We should charge something extra for the costs of row locking and
3592 : : * possible refetches, but it's hard to say how much. For now, use
3593 : : * cpu_tuple_cost per row.
3594 : : */
381 rhaas@postgresql.org 3595 : 4110 : pathnode->path.disabled_nodes = subpath->disabled_nodes;
3470 tgl@sss.pgh.pa.us 3596 : 4110 : pathnode->path.startup_cost = subpath->startup_cost;
3597 : 4110 : pathnode->path.total_cost = subpath->total_cost +
3598 : 4110 : cpu_tuple_cost * subpath->rows;
3599 : :
3600 : 4110 : return pathnode;
3601 : : }
3602 : :
3603 : : /*
3604 : : * create_modifytable_path
3605 : : * Creates a pathnode that represents performing INSERT/UPDATE/DELETE/MERGE
3606 : : * mods
3607 : : *
3608 : : * 'rel' is the parent relation associated with the result
3609 : : * 'subpath' is a Path producing source data
3610 : : * 'operation' is the operation type
3611 : : * 'canSetTag' is true if we set the command tag/es_processed
3612 : : * 'nominalRelation' is the parent RT index for use of EXPLAIN
3613 : : * 'rootRelation' is the partitioned/inherited table root RTI, or 0 if none
3614 : : * 'partColsUpdated' is true if any partitioning columns are being updated,
3615 : : * either from the target relation or a descendent partitioned table.
3616 : : * 'resultRelations' is an integer list of actual RT indexes of target rel(s)
3617 : : * 'updateColnosLists' is a list of UPDATE target column number lists
3618 : : * (one sublist per rel); or NIL if not an UPDATE
3619 : : * 'withCheckOptionLists' is a list of WCO lists (one per rel)
3620 : : * 'returningLists' is a list of RETURNING tlists (one per rel)
3621 : : * 'rowMarks' is a list of PlanRowMarks (non-locking only)
3622 : : * 'onconflict' is the ON CONFLICT clause, or NULL
3623 : : * 'epqParam' is the ID of Param for EvalPlanQual re-eval
3624 : : * 'mergeActionLists' is a list of lists of MERGE actions (one per rel)
3625 : : * 'mergeJoinConditions' is a list of join conditions for MERGE (one per rel)
3626 : : */
3627 : : ModifyTablePath *
3628 : 43084 : create_modifytable_path(PlannerInfo *root, RelOptInfo *rel,
3629 : : Path *subpath,
3630 : : CmdType operation, bool canSetTag,
3631 : : Index nominalRelation, Index rootRelation,
3632 : : bool partColsUpdated,
3633 : : List *resultRelations,
3634 : : List *updateColnosLists,
3635 : : List *withCheckOptionLists, List *returningLists,
3636 : : List *rowMarks, OnConflictExpr *onconflict,
3637 : : List *mergeActionLists, List *mergeJoinConditions,
3638 : : int epqParam)
3639 : : {
3640 : 43084 : ModifyTablePath *pathnode = makeNode(ModifyTablePath);
3641 : :
1258 alvherre@alvh.no-ip. 3642 [ + + + + : 43084 : Assert(operation == CMD_MERGE ||
- + ]
3643 : : (operation == CMD_UPDATE ?
3644 : : list_length(resultRelations) == list_length(updateColnosLists) :
3645 : : updateColnosLists == NIL));
3470 tgl@sss.pgh.pa.us 3646 [ + + - + ]: 43084 : Assert(withCheckOptionLists == NIL ||
3647 : : list_length(resultRelations) == list_length(withCheckOptionLists));
3648 [ + + - + ]: 43084 : Assert(returningLists == NIL ||
3649 : : list_length(resultRelations) == list_length(returningLists));
3650 : :
3651 : 43084 : pathnode->path.pathtype = T_ModifyTable;
3652 : 43084 : pathnode->path.parent = rel;
3653 : : /* pathtarget is not interesting, just make it minimally valid */
3463 3654 : 43084 : pathnode->path.pathtarget = rel->reltarget;
3655 : : /* For now, assume we are above any joins, so no parameterization */
3470 3656 : 43084 : pathnode->path.param_info = NULL;
3657 : 43084 : pathnode->path.parallel_aware = false;
3658 : 43084 : pathnode->path.parallel_safe = false;
3376 rhaas@postgresql.org 3659 : 43084 : pathnode->path.parallel_workers = 0;
3470 tgl@sss.pgh.pa.us 3660 : 43084 : pathnode->path.pathkeys = NIL;
3661 : :
3662 : : /*
3663 : : * Compute cost & rowcount as subpath cost & rowcount (if RETURNING)
3664 : : *
3665 : : * Currently, we don't charge anything extra for the actual table
3666 : : * modification work, nor for the WITH CHECK OPTIONS or RETURNING
3667 : : * expressions if any. It would only be window dressing, since
3668 : : * ModifyTable is always a top-level node and there is no way for the
3669 : : * costs to change any higher-level planning choices. But we might want
3670 : : * to make it look better sometime.
3671 : : */
381 rhaas@postgresql.org 3672 : 43084 : pathnode->path.disabled_nodes = subpath->disabled_nodes;
1620 tgl@sss.pgh.pa.us 3673 : 43084 : pathnode->path.startup_cost = subpath->startup_cost;
3674 : 43084 : pathnode->path.total_cost = subpath->total_cost;
3675 [ + + ]: 43084 : if (returningLists != NIL)
3676 : : {
3677 : 1451 : pathnode->path.rows = subpath->rows;
3678 : :
3679 : : /*
3680 : : * Set width to match the subpath output. XXX this is totally wrong:
3681 : : * we should return an average of the RETURNING tlist widths. But
3682 : : * it's what happened historically, and improving it is a task for
3683 : : * another day. (Again, it's mostly window dressing.)
3684 : : */
3685 : 1451 : pathnode->path.pathtarget->width = subpath->pathtarget->width;
3686 : : }
3687 : : else
3688 : : {
3689 : 41633 : pathnode->path.rows = 0;
3690 : 41633 : pathnode->path.pathtarget->width = 0;
3691 : : }
3692 : :
3693 : 43084 : pathnode->subpath = subpath;
3470 3694 : 43084 : pathnode->operation = operation;
3695 : 43084 : pathnode->canSetTag = canSetTag;
3696 : 43084 : pathnode->nominalRelation = nominalRelation;
2526 3697 : 43084 : pathnode->rootRelation = rootRelation;
2787 rhaas@postgresql.org 3698 : 43084 : pathnode->partColsUpdated = partColsUpdated;
3470 tgl@sss.pgh.pa.us 3699 : 43084 : pathnode->resultRelations = resultRelations;
1620 3700 : 43084 : pathnode->updateColnosLists = updateColnosLists;
3470 3701 : 43084 : pathnode->withCheckOptionLists = withCheckOptionLists;
3702 : 43084 : pathnode->returningLists = returningLists;
3703 : 43084 : pathnode->rowMarks = rowMarks;
3704 : 43084 : pathnode->onconflict = onconflict;
3705 : 43084 : pathnode->epqParam = epqParam;
1258 alvherre@alvh.no-ip. 3706 : 43084 : pathnode->mergeActionLists = mergeActionLists;
525 dean.a.rasheed@gmail 3707 : 43084 : pathnode->mergeJoinConditions = mergeJoinConditions;
3708 : :
3470 tgl@sss.pgh.pa.us 3709 : 43084 : return pathnode;
3710 : : }
3711 : :
3712 : : /*
3713 : : * create_limit_path
3714 : : * Creates a pathnode that represents performing LIMIT/OFFSET
3715 : : *
3716 : : * In addition to providing the actual OFFSET and LIMIT expressions,
3717 : : * the caller must provide estimates of their values for costing purposes.
3718 : : * The estimates are as computed by preprocess_limit(), ie, 0 represents
3719 : : * the clause not being present, and -1 means it's present but we could
3720 : : * not estimate its value.
3721 : : *
3722 : : * 'rel' is the parent relation associated with the result
3723 : : * 'subpath' is the path representing the source of data
3724 : : * 'limitOffset' is the actual OFFSET expression, or NULL
3725 : : * 'limitCount' is the actual LIMIT expression, or NULL
3726 : : * 'offset_est' is the estimated value of the OFFSET expression
3727 : : * 'count_est' is the estimated value of the LIMIT expression
3728 : : */
3729 : : LimitPath *
3730 : 3015 : create_limit_path(PlannerInfo *root, RelOptInfo *rel,
3731 : : Path *subpath,
3732 : : Node *limitOffset, Node *limitCount,
3733 : : LimitOption limitOption,
3734 : : int64 offset_est, int64 count_est)
3735 : : {
3736 : 3015 : LimitPath *pathnode = makeNode(LimitPath);
3737 : :
3738 : 3015 : pathnode->path.pathtype = T_Limit;
3739 : 3015 : pathnode->path.parent = rel;
3740 : : /* Limit doesn't project, so use source path's pathtarget */
3741 : 3015 : pathnode->path.pathtarget = subpath->pathtarget;
3742 : : /* For now, assume we are above any joins, so no parameterization */
3743 : 3015 : pathnode->path.param_info = NULL;
3744 : 3015 : pathnode->path.parallel_aware = false;
3745 [ + + ]: 4211 : pathnode->path.parallel_safe = rel->consider_parallel &&
3746 [ + + ]: 1196 : subpath->parallel_safe;
3376 rhaas@postgresql.org 3747 : 3015 : pathnode->path.parallel_workers = subpath->parallel_workers;
3470 tgl@sss.pgh.pa.us 3748 : 3015 : pathnode->path.rows = subpath->rows;
381 rhaas@postgresql.org 3749 : 3015 : pathnode->path.disabled_nodes = subpath->disabled_nodes;
3470 tgl@sss.pgh.pa.us 3750 : 3015 : pathnode->path.startup_cost = subpath->startup_cost;
3751 : 3015 : pathnode->path.total_cost = subpath->total_cost;
3752 : 3015 : pathnode->path.pathkeys = subpath->pathkeys;
3753 : 3015 : pathnode->subpath = subpath;
3754 : 3015 : pathnode->limitOffset = limitOffset;
3755 : 3015 : pathnode->limitCount = limitCount;
1978 alvherre@alvh.no-ip. 3756 : 3015 : pathnode->limitOption = limitOption;
3757 : :
3758 : : /*
3759 : : * Adjust the output rows count and costs according to the offset/limit.
3760 : : */
2349 efujita@postgresql.o 3761 : 3015 : adjust_limit_rows_costs(&pathnode->path.rows,
3762 : : &pathnode->path.startup_cost,
3763 : : &pathnode->path.total_cost,
3764 : : offset_est, count_est);
3765 : :
3766 : 3015 : return pathnode;
3767 : : }
3768 : :
3769 : : /*
3770 : : * adjust_limit_rows_costs
3771 : : * Adjust the size and cost estimates for a LimitPath node according to the
3772 : : * offset/limit.
3773 : : *
3774 : : * This is only a cosmetic issue if we are at top level, but if we are
3775 : : * building a subquery then it's important to report correct info to the outer
3776 : : * planner.
3777 : : *
3778 : : * When the offset or count couldn't be estimated, use 10% of the estimated
3779 : : * number of rows emitted from the subpath.
3780 : : *
3781 : : * XXX we don't bother to add eval costs of the offset/limit expressions
3782 : : * themselves to the path costs. In theory we should, but in most cases those
3783 : : * expressions are trivial and it's just not worth the trouble.
3784 : : */
3785 : : void
3786 : 3107 : adjust_limit_rows_costs(double *rows, /* in/out parameter */
3787 : : Cost *startup_cost, /* in/out parameter */
3788 : : Cost *total_cost, /* in/out parameter */
3789 : : int64 offset_est,
3790 : : int64 count_est)
3791 : : {
3792 : 3107 : double input_rows = *rows;
3793 : 3107 : Cost input_startup_cost = *startup_cost;
3794 : 3107 : Cost input_total_cost = *total_cost;
3795 : :
3470 tgl@sss.pgh.pa.us 3796 [ + + ]: 3107 : if (offset_est != 0)
3797 : : {
3798 : : double offset_rows;
3799 : :
3800 [ + + ]: 347 : if (offset_est > 0)
3801 : 335 : offset_rows = (double) offset_est;
3802 : : else
2349 efujita@postgresql.o 3803 : 12 : offset_rows = clamp_row_est(input_rows * 0.10);
3804 [ + + ]: 347 : if (offset_rows > *rows)
3805 : 23 : offset_rows = *rows;
3806 [ + - ]: 347 : if (input_rows > 0)
3807 : 347 : *startup_cost +=
3808 : 347 : (input_total_cost - input_startup_cost)
3809 : 347 : * offset_rows / input_rows;
3810 : 347 : *rows -= offset_rows;
3811 [ + + ]: 347 : if (*rows < 1)
3812 : 27 : *rows = 1;
3813 : : }
3814 : :
3470 tgl@sss.pgh.pa.us 3815 [ + + ]: 3107 : if (count_est != 0)
3816 : : {
3817 : : double count_rows;
3818 : :
3819 [ + + ]: 3078 : if (count_est > 0)
3820 : 3075 : count_rows = (double) count_est;
3821 : : else
2349 efujita@postgresql.o 3822 : 3 : count_rows = clamp_row_est(input_rows * 0.10);
3823 [ + + ]: 3078 : if (count_rows > *rows)
3824 : 136 : count_rows = *rows;
3825 [ + - ]: 3078 : if (input_rows > 0)
3826 : 3078 : *total_cost = *startup_cost +
3827 : 3078 : (input_total_cost - input_startup_cost)
3828 : 3078 : * count_rows / input_rows;
3829 : 3078 : *rows = count_rows;
3830 [ - + ]: 3078 : if (*rows < 1)
2349 efujita@postgresql.o 3831 :UBC 0 : *rows = 1;
3832 : : }
3470 tgl@sss.pgh.pa.us 3833 :CBC 3107 : }
3834 : :
3835 : :
3836 : : /*
3837 : : * reparameterize_path
3838 : : * Attempt to modify a Path to have greater parameterization
3839 : : *
3840 : : * We use this to attempt to bring all child paths of an appendrel to the
3841 : : * same parameterization level, ensuring that they all enforce the same set
3842 : : * of join quals (and thus that that parameterization can be attributed to
3843 : : * an append path built from such paths). Currently, only a few path types
3844 : : * are supported here, though more could be added at need. We return NULL
3845 : : * if we can't reparameterize the given path.
3846 : : *
3847 : : * Note: we intentionally do not pass created paths to add_path(); it would
3848 : : * possibly try to delete them on the grounds of being cost-inferior to the
3849 : : * paths they were made from, and we don't want that. Paths made here are
3850 : : * not necessarily of general-purpose usefulness, but they can be useful
3851 : : * as members of an append path.
3852 : : */
3853 : : Path *
4888 3854 : 178 : reparameterize_path(PlannerInfo *root, Path *path,
3855 : : Relids required_outer,
3856 : : double loop_count)
3857 : : {
3858 : 178 : RelOptInfo *rel = path->parent;
3859 : :
3860 : : /* Can only increase, not decrease, path's parameterization */
3861 [ - + - + ]: 178 : if (!bms_is_subset(PATH_REQ_OUTER(path), required_outer))
4888 tgl@sss.pgh.pa.us 3862 :UBC 0 : return NULL;
4888 tgl@sss.pgh.pa.us 3863 [ + - - - :CBC 178 : switch (path->pathtype)
- + - - -
+ ]
3864 : : {
3865 : 132 : case T_SeqScan:
3587 rhaas@postgresql.org 3866 : 132 : return create_seqscan_path(root, rel, required_outer, 0);
3696 tgl@sss.pgh.pa.us 3867 :UBC 0 : case T_SampleScan:
3868 : 0 : return (Path *) create_samplescan_path(root, rel, required_outer);
4888 3869 : 0 : case T_IndexScan:
3870 : : case T_IndexOnlyScan:
3871 : : {
4836 bruce@momjian.us 3872 : 0 : IndexPath *ipath = (IndexPath *) path;
3873 : 0 : IndexPath *newpath = makeNode(IndexPath);
3874 : :
3875 : : /*
3876 : : * We can't use create_index_path directly, and would not want
3877 : : * to because it would re-compute the indexqual conditions
3878 : : * which is wasted effort. Instead we hack things a bit:
3879 : : * flat-copy the path node, revise its param_info, and redo
3880 : : * the cost estimate.
3881 : : */
3882 : 0 : memcpy(newpath, ipath, sizeof(IndexPath));
3883 : 0 : newpath->path.param_info =
3884 : 0 : get_baserel_parampathinfo(root, rel, required_outer);
3125 rhaas@postgresql.org 3885 : 0 : cost_index(newpath, root, loop_count, false);
4836 bruce@momjian.us 3886 : 0 : return (Path *) newpath;
3887 : : }
4888 tgl@sss.pgh.pa.us 3888 : 0 : case T_BitmapHeapScan:
3889 : : {
4836 bruce@momjian.us 3890 : 0 : BitmapHeapPath *bpath = (BitmapHeapPath *) path;
3891 : :
3892 : 0 : return (Path *) create_bitmap_heap_path(root,
3893 : : rel,
3894 : : bpath->bitmapqual,
3895 : : required_outer,
3896 : : loop_count, 0);
3897 : : }
4888 tgl@sss.pgh.pa.us 3898 : 0 : case T_SubqueryScan:
3899 : : {
3470 3900 : 0 : SubqueryScanPath *spath = (SubqueryScanPath *) path;
1145 3901 : 0 : Path *subpath = spath->subpath;
3902 : : bool trivial_pathtarget;
3903 : :
3904 : : /*
3905 : : * If existing node has zero extra cost, we must have decided
3906 : : * its target is trivial. (The converse is not true, because
3907 : : * it might have a trivial target but quals to enforce; but in
3908 : : * that case the new node will too, so it doesn't matter
3909 : : * whether we get the right answer here.)
3910 : : */
3911 : 0 : trivial_pathtarget =
3912 : 0 : (subpath->total_cost == spath->path.total_cost);
3913 : :
3470 3914 : 0 : return (Path *) create_subqueryscan_path(root,
3915 : : rel,
3916 : : subpath,
3917 : : trivial_pathtarget,
3918 : : spath->path.pathkeys,
3919 : : required_outer);
3920 : : }
2413 tgl@sss.pgh.pa.us 3921 :CBC 30 : case T_Result:
3922 : : /* Supported only for RTE_RESULT scan paths */
3923 [ + - ]: 30 : if (IsA(path, Path))
3924 : 30 : return create_resultscan_path(root, rel, required_outer);
2413 tgl@sss.pgh.pa.us 3925 :UBC 0 : break;
2783 3926 : 0 : case T_Append:
3927 : : {
3928 : 0 : AppendPath *apath = (AppendPath *) path;
3929 : 0 : List *childpaths = NIL;
3930 : 0 : List *partialpaths = NIL;
3931 : : int i;
3932 : : ListCell *lc;
3933 : :
3934 : : /* Reparameterize the children */
3935 : 0 : i = 0;
3936 [ # # # # : 0 : foreach(lc, apath->subpaths)
# # ]
3937 : : {
3938 : 0 : Path *spath = (Path *) lfirst(lc);
3939 : :
3940 : 0 : spath = reparameterize_path(root, spath,
3941 : : required_outer,
3942 : : loop_count);
3943 [ # # ]: 0 : if (spath == NULL)
3944 : 0 : return NULL;
3945 : : /* We have to re-split the regular and partial paths */
3946 [ # # ]: 0 : if (i < apath->first_partial_path)
3947 : 0 : childpaths = lappend(childpaths, spath);
3948 : : else
3949 : 0 : partialpaths = lappend(partialpaths, spath);
3950 : 0 : i++;
3951 : : }
3952 : 0 : return (Path *)
2709 alvherre@alvh.no-ip. 3953 : 0 : create_append_path(root, rel, childpaths, partialpaths,
3954 : : apath->path.pathkeys, required_outer,
3955 : : apath->path.parallel_workers,
2783 tgl@sss.pgh.pa.us 3956 : 0 : apath->path.parallel_aware,
3957 : : -1);
3958 : : }
1007 3959 : 0 : case T_Material:
3960 : : {
3961 : 0 : MaterialPath *mpath = (MaterialPath *) path;
3962 : 0 : Path *spath = mpath->subpath;
3963 : :
3964 : 0 : spath = reparameterize_path(root, spath,
3965 : : required_outer,
3966 : : loop_count);
3967 [ # # ]: 0 : if (spath == NULL)
3968 : 0 : return NULL;
3969 : 0 : return (Path *) create_material_path(rel, spath);
3970 : : }
1515 drowley@postgresql.o 3971 : 0 : case T_Memoize:
3972 : : {
3973 : 0 : MemoizePath *mpath = (MemoizePath *) path;
1007 tgl@sss.pgh.pa.us 3974 : 0 : Path *spath = mpath->subpath;
3975 : :
3976 : 0 : spath = reparameterize_path(root, spath,
3977 : : required_outer,
3978 : : loop_count);
3979 [ # # ]: 0 : if (spath == NULL)
3980 : 0 : return NULL;
1515 drowley@postgresql.o 3981 : 0 : return (Path *) create_memoize_path(root, rel,
3982 : : spath,
3983 : : mpath->param_exprs,
3984 : : mpath->hash_operators,
3985 : 0 : mpath->singlerow,
1382 3986 : 0 : mpath->binary_mode,
3987 : : mpath->est_calls);
3988 : : }
4888 tgl@sss.pgh.pa.us 3989 :CBC 16 : default:
3990 : 16 : break;
3991 : : }
3992 : 16 : return NULL;
3993 : : }
3994 : :
3995 : : /*
3996 : : * reparameterize_path_by_child
3997 : : * Given a path parameterized by the parent of the given child relation,
3998 : : * translate the path to be parameterized by the given child relation.
3999 : : *
4000 : : * Most fields in the path are not changed, but any expressions must be
4001 : : * adjusted to refer to the correct varnos, and any subpaths must be
4002 : : * recursively reparameterized. Other fields that refer to specific relids
4003 : : * also need adjustment.
4004 : : *
4005 : : * The cost, number of rows, width and parallel path properties depend upon
4006 : : * path->parent, which does not change during the translation. So we need
4007 : : * not change those.
4008 : : *
4009 : : * Currently, only a few path types are supported here, though more could be
4010 : : * added at need. We return NULL if we can't reparameterize the given path.
4011 : : *
4012 : : * Note that this function can change referenced RangeTblEntries, RelOptInfos
4013 : : * and IndexOptInfos as well as the Path structures. Therefore, it's only safe
4014 : : * to call during create_plan(), when we have made a final choice of which Path
4015 : : * to use for each RangeTblEntry/RelOptInfo/IndexOptInfo.
4016 : : *
4017 : : * Keep this code in sync with path_is_reparameterizable_by_child()!
4018 : : */
4019 : : Path *
2892 rhaas@postgresql.org 4020 : 46164 : reparameterize_path_by_child(PlannerInfo *root, Path *path,
4021 : : RelOptInfo *child_rel)
4022 : : {
4023 : : Path *new_path;
4024 : : ParamPathInfo *new_ppi;
4025 : : ParamPathInfo *old_ppi;
4026 : : Relids required_outer;
4027 : :
4028 : : #define ADJUST_CHILD_ATTRS(node) \
4029 : : ((node) = (void *) adjust_appendrel_attrs_multilevel(root, \
4030 : : (Node *) (node), \
4031 : : child_rel, \
4032 : : child_rel->top_parent))
4033 : :
4034 : : #define REPARAMETERIZE_CHILD_PATH(path) \
4035 : : do { \
4036 : : (path) = reparameterize_path_by_child(root, (path), child_rel); \
4037 : : if ((path) == NULL) \
4038 : : return NULL; \
4039 : : } while(0)
4040 : :
4041 : : #define REPARAMETERIZE_CHILD_PATH_LIST(pathlist) \
4042 : : do { \
4043 : : if ((pathlist) != NIL) \
4044 : : { \
4045 : : (pathlist) = reparameterize_pathlist_by_child(root, (pathlist), \
4046 : : child_rel); \
4047 : : if ((pathlist) == NIL) \
4048 : : return NULL; \
4049 : : } \
4050 : : } while(0)
4051 : :
4052 : : /*
4053 : : * If the path is not parameterized by the parent of the given relation,
4054 : : * it doesn't need reparameterization.
4055 : : */
4056 [ + + ]: 46164 : if (!path->param_info ||
4057 [ + - + + ]: 22729 : !bms_overlap(PATH_REQ_OUTER(path), child_rel->top_parent_relids))
4058 : 45651 : return path;
4059 : :
4060 : : /*
4061 : : * If possible, reparameterize the given path.
4062 : : *
4063 : : * This function is currently only applied to the inner side of a nestloop
4064 : : * join that is being partitioned by the partitionwise-join code. Hence,
4065 : : * we need only support path types that plausibly arise in that context.
4066 : : * (In particular, supporting sorted path types would be a waste of code
4067 : : * and cycles: even if we translated them here, they'd just lose in
4068 : : * subsequent cost comparisons.) If we do see an unsupported path type,
4069 : : * that just means we won't be able to generate a partitionwise-join plan
4070 : : * using that path type.
4071 : : */
4072 [ + + + + : 513 : switch (nodeTag(path))
+ - - + -
+ + - + -
- ]
4073 : : {
4074 : 114 : case T_Path:
536 tgl@sss.pgh.pa.us 4075 : 114 : new_path = path;
4076 : 114 : ADJUST_CHILD_ATTRS(new_path->parent->baserestrictinfo);
4077 [ + + ]: 114 : if (path->pathtype == T_SampleScan)
4078 : : {
4079 : 24 : Index scan_relid = path->parent->relid;
4080 : : RangeTblEntry *rte;
4081 : :
4082 : : /* it should be a base rel with a tablesample clause... */
4083 [ - + ]: 24 : Assert(scan_relid > 0);
4084 [ + - ]: 24 : rte = planner_rt_fetch(scan_relid, root);
4085 [ - + ]: 24 : Assert(rte->rtekind == RTE_RELATION);
4086 [ - + ]: 24 : Assert(rte->tablesample != NULL);
4087 : :
4088 : 24 : ADJUST_CHILD_ATTRS(rte->tablesample);
4089 : : }
2892 rhaas@postgresql.org 4090 : 114 : break;
4091 : :
4092 : 264 : case T_IndexPath:
4093 : : {
536 tgl@sss.pgh.pa.us 4094 : 264 : IndexPath *ipath = (IndexPath *) path;
4095 : :
4096 : 264 : ADJUST_CHILD_ATTRS(ipath->indexinfo->indrestrictinfo);
2892 rhaas@postgresql.org 4097 : 264 : ADJUST_CHILD_ATTRS(ipath->indexclauses);
4098 : 264 : new_path = (Path *) ipath;
4099 : : }
4100 : 264 : break;
4101 : :
4102 : 24 : case T_BitmapHeapPath:
4103 : : {
536 tgl@sss.pgh.pa.us 4104 : 24 : BitmapHeapPath *bhpath = (BitmapHeapPath *) path;
4105 : :
4106 : 24 : ADJUST_CHILD_ATTRS(bhpath->path.parent->baserestrictinfo);
2892 rhaas@postgresql.org 4107 [ - + ]: 24 : REPARAMETERIZE_CHILD_PATH(bhpath->bitmapqual);
4108 : 24 : new_path = (Path *) bhpath;
4109 : : }
4110 : 24 : break;
4111 : :
4112 : 12 : case T_BitmapAndPath:
4113 : : {
536 tgl@sss.pgh.pa.us 4114 : 12 : BitmapAndPath *bapath = (BitmapAndPath *) path;
4115 : :
2892 rhaas@postgresql.org 4116 [ + - - + ]: 12 : REPARAMETERIZE_CHILD_PATH_LIST(bapath->bitmapquals);
4117 : 12 : new_path = (Path *) bapath;
4118 : : }
4119 : 12 : break;
4120 : :
4121 : 12 : case T_BitmapOrPath:
4122 : : {
536 tgl@sss.pgh.pa.us 4123 : 12 : BitmapOrPath *bopath = (BitmapOrPath *) path;
4124 : :
2892 rhaas@postgresql.org 4125 [ + - - + ]: 12 : REPARAMETERIZE_CHILD_PATH_LIST(bopath->bitmapquals);
4126 : 12 : new_path = (Path *) bopath;
4127 : : }
4128 : 12 : break;
4129 : :
2892 rhaas@postgresql.org 4130 :UBC 0 : case T_ForeignPath:
4131 : : {
536 tgl@sss.pgh.pa.us 4132 : 0 : ForeignPath *fpath = (ForeignPath *) path;
4133 : : ReparameterizeForeignPathByChild_function rfpc_func;
4134 : :
4135 : 0 : ADJUST_CHILD_ATTRS(fpath->path.parent->baserestrictinfo);
2892 rhaas@postgresql.org 4136 [ # # ]: 0 : if (fpath->fdw_outerpath)
4137 [ # # ]: 0 : REPARAMETERIZE_CHILD_PATH(fpath->fdw_outerpath);
753 efujita@postgresql.o 4138 [ # # ]: 0 : if (fpath->fdw_restrictinfo)
4139 : 0 : ADJUST_CHILD_ATTRS(fpath->fdw_restrictinfo);
4140 : :
4141 : : /* Hand over to FDW if needed. */
2892 rhaas@postgresql.org 4142 : 0 : rfpc_func =
4143 : 0 : path->parent->fdwroutine->ReparameterizeForeignPathByChild;
4144 [ # # ]: 0 : if (rfpc_func)
4145 : 0 : fpath->fdw_private = rfpc_func(root, fpath->fdw_private,
4146 : : child_rel);
4147 : 0 : new_path = (Path *) fpath;
4148 : : }
4149 : 0 : break;
4150 : :
4151 : 0 : case T_CustomPath:
4152 : : {
536 tgl@sss.pgh.pa.us 4153 : 0 : CustomPath *cpath = (CustomPath *) path;
4154 : :
4155 : 0 : ADJUST_CHILD_ATTRS(cpath->path.parent->baserestrictinfo);
2892 rhaas@postgresql.org 4156 [ # # # # ]: 0 : REPARAMETERIZE_CHILD_PATH_LIST(cpath->custom_paths);
753 efujita@postgresql.o 4157 [ # # ]: 0 : if (cpath->custom_restrictinfo)
4158 : 0 : ADJUST_CHILD_ATTRS(cpath->custom_restrictinfo);
2892 rhaas@postgresql.org 4159 [ # # ]: 0 : if (cpath->methods &&
4160 [ # # ]: 0 : cpath->methods->ReparameterizeCustomPathByChild)
4161 : 0 : cpath->custom_private =
4162 : 0 : cpath->methods->ReparameterizeCustomPathByChild(root,
4163 : : cpath->custom_private,
4164 : : child_rel);
4165 : 0 : new_path = (Path *) cpath;
4166 : : }
4167 : 0 : break;
4168 : :
2892 rhaas@postgresql.org 4169 :CBC 18 : case T_NestPath:
4170 : : {
536 tgl@sss.pgh.pa.us 4171 : 18 : NestPath *npath = (NestPath *) path;
4172 : 18 : JoinPath *jpath = (JoinPath *) npath;
4173 : :
2892 rhaas@postgresql.org 4174 [ - + ]: 18 : REPARAMETERIZE_CHILD_PATH(jpath->outerjoinpath);
4175 [ - + ]: 18 : REPARAMETERIZE_CHILD_PATH(jpath->innerjoinpath);
4176 : 18 : ADJUST_CHILD_ATTRS(jpath->joinrestrictinfo);
1490 peter@eisentraut.org 4177 : 18 : new_path = (Path *) npath;
4178 : : }
2892 rhaas@postgresql.org 4179 : 18 : break;
4180 : :
2892 rhaas@postgresql.org 4181 :UBC 0 : case T_MergePath:
4182 : : {
536 tgl@sss.pgh.pa.us 4183 : 0 : MergePath *mpath = (MergePath *) path;
4184 : 0 : JoinPath *jpath = (JoinPath *) mpath;
4185 : :
2892 rhaas@postgresql.org 4186 [ # # ]: 0 : REPARAMETERIZE_CHILD_PATH(jpath->outerjoinpath);
4187 [ # # ]: 0 : REPARAMETERIZE_CHILD_PATH(jpath->innerjoinpath);
4188 : 0 : ADJUST_CHILD_ATTRS(jpath->joinrestrictinfo);
4189 : 0 : ADJUST_CHILD_ATTRS(mpath->path_mergeclauses);
4190 : 0 : new_path = (Path *) mpath;
4191 : : }
4192 : 0 : break;
4193 : :
2892 rhaas@postgresql.org 4194 :CBC 24 : case T_HashPath:
4195 : : {
536 tgl@sss.pgh.pa.us 4196 : 24 : HashPath *hpath = (HashPath *) path;
4197 : 24 : JoinPath *jpath = (JoinPath *) hpath;
4198 : :
2892 rhaas@postgresql.org 4199 [ - + ]: 24 : REPARAMETERIZE_CHILD_PATH(jpath->outerjoinpath);
4200 [ - + ]: 24 : REPARAMETERIZE_CHILD_PATH(jpath->innerjoinpath);
4201 : 24 : ADJUST_CHILD_ATTRS(jpath->joinrestrictinfo);
4202 : 24 : ADJUST_CHILD_ATTRS(hpath->path_hashclauses);
4203 : 24 : new_path = (Path *) hpath;
4204 : : }
4205 : 24 : break;
4206 : :
4207 : 12 : case T_AppendPath:
4208 : : {
536 tgl@sss.pgh.pa.us 4209 : 12 : AppendPath *apath = (AppendPath *) path;
4210 : :
2892 rhaas@postgresql.org 4211 [ + - - + ]: 12 : REPARAMETERIZE_CHILD_PATH_LIST(apath->subpaths);
4212 : 12 : new_path = (Path *) apath;
4213 : : }
4214 : 12 : break;
4215 : :
1007 tgl@sss.pgh.pa.us 4216 :UBC 0 : case T_MaterialPath:
4217 : : {
536 4218 : 0 : MaterialPath *mpath = (MaterialPath *) path;
4219 : :
1007 4220 [ # # ]: 0 : REPARAMETERIZE_CHILD_PATH(mpath->subpath);
4221 : 0 : new_path = (Path *) mpath;
4222 : : }
4223 : 0 : break;
4224 : :
1515 drowley@postgresql.o 4225 :CBC 33 : case T_MemoizePath:
4226 : : {
536 tgl@sss.pgh.pa.us 4227 : 33 : MemoizePath *mpath = (MemoizePath *) path;
4228 : :
1515 drowley@postgresql.o 4229 [ - + ]: 33 : REPARAMETERIZE_CHILD_PATH(mpath->subpath);
1006 tgl@sss.pgh.pa.us 4230 : 33 : ADJUST_CHILD_ATTRS(mpath->param_exprs);
1515 drowley@postgresql.o 4231 : 33 : new_path = (Path *) mpath;
4232 : : }
1618 4233 : 33 : break;
4234 : :
2892 rhaas@postgresql.org 4235 :UBC 0 : case T_GatherPath:
4236 : : {
536 tgl@sss.pgh.pa.us 4237 : 0 : GatherPath *gpath = (GatherPath *) path;
4238 : :
2892 rhaas@postgresql.org 4239 [ # # ]: 0 : REPARAMETERIZE_CHILD_PATH(gpath->subpath);
4240 : 0 : new_path = (Path *) gpath;
4241 : : }
4242 : 0 : break;
4243 : :
4244 : 0 : default:
4245 : : /* We don't know how to reparameterize this path. */
4246 : 0 : return NULL;
4247 : : }
4248 : :
4249 : : /*
4250 : : * Adjust the parameterization information, which refers to the topmost
4251 : : * parent. The topmost parent can be multiple levels away from the given
4252 : : * child, hence use multi-level expression adjustment routines.
4253 : : */
2892 rhaas@postgresql.org 4254 :CBC 513 : old_ppi = new_path->param_info;
4255 : : required_outer =
4256 : 513 : adjust_child_relids_multilevel(root, old_ppi->ppi_req_outer,
4257 : : child_rel,
1115 tgl@sss.pgh.pa.us 4258 : 513 : child_rel->top_parent);
4259 : :
4260 : : /* If we already have a PPI for this parameterization, just return it */
2892 rhaas@postgresql.org 4261 : 513 : new_ppi = find_param_path_info(new_path->parent, required_outer);
4262 : :
4263 : : /*
4264 : : * If not, build a new one and link it to the list of PPIs. For the same
4265 : : * reason as explained in mark_dummy_rel(), allocate new PPI in the same
4266 : : * context the given RelOptInfo is in.
4267 : : */
4268 [ + + ]: 513 : if (new_ppi == NULL)
4269 : : {
4270 : : MemoryContext oldcontext;
4271 : 432 : RelOptInfo *rel = path->parent;
4272 : :
4273 : 432 : oldcontext = MemoryContextSwitchTo(GetMemoryChunkContext(rel));
4274 : :
4275 : 432 : new_ppi = makeNode(ParamPathInfo);
4276 : 432 : new_ppi->ppi_req_outer = bms_copy(required_outer);
4277 : 432 : new_ppi->ppi_rows = old_ppi->ppi_rows;
4278 : 432 : new_ppi->ppi_clauses = old_ppi->ppi_clauses;
4279 : 432 : ADJUST_CHILD_ATTRS(new_ppi->ppi_clauses);
950 tgl@sss.pgh.pa.us 4280 : 432 : new_ppi->ppi_serials = bms_copy(old_ppi->ppi_serials);
2892 rhaas@postgresql.org 4281 : 432 : rel->ppilist = lappend(rel->ppilist, new_ppi);
4282 : :
4283 : 432 : MemoryContextSwitchTo(oldcontext);
4284 : : }
4285 : 513 : bms_free(required_outer);
4286 : :
4287 : 513 : new_path->param_info = new_ppi;
4288 : :
4289 : : /*
4290 : : * Adjust the path target if the parent of the outer relation is
4291 : : * referenced in the targetlist. This can happen when only the parent of
4292 : : * outer relation is laterally referenced in this relation.
4293 : : */
4294 [ + + ]: 513 : if (bms_overlap(path->parent->lateral_relids,
4295 : 513 : child_rel->top_parent_relids))
4296 : : {
4297 : 240 : new_path->pathtarget = copy_pathtarget(new_path->pathtarget);
4298 : 240 : ADJUST_CHILD_ATTRS(new_path->pathtarget->exprs);
4299 : : }
4300 : :
4301 : 513 : return new_path;
4302 : : }
4303 : :
4304 : : /*
4305 : : * path_is_reparameterizable_by_child
4306 : : * Given a path parameterized by the parent of the given child relation,
4307 : : * see if it can be translated to be parameterized by the child relation.
4308 : : *
4309 : : * This must return true if and only if reparameterize_path_by_child()
4310 : : * would succeed on this path. Currently it's sufficient to verify that
4311 : : * the path and all of its subpaths (if any) are of the types handled by
4312 : : * that function. However, subpaths that are not parameterized can be
4313 : : * disregarded since they won't require translation.
4314 : : */
4315 : : bool
536 tgl@sss.pgh.pa.us 4316 : 18612 : path_is_reparameterizable_by_child(Path *path, RelOptInfo *child_rel)
4317 : : {
4318 : : #define REJECT_IF_PATH_NOT_REPARAMETERIZABLE(path) \
4319 : : do { \
4320 : : if (!path_is_reparameterizable_by_child(path, child_rel)) \
4321 : : return false; \
4322 : : } while(0)
4323 : :
4324 : : #define REJECT_IF_PATH_LIST_NOT_REPARAMETERIZABLE(pathlist) \
4325 : : do { \
4326 : : if (!pathlist_is_reparameterizable_by_child(pathlist, child_rel)) \
4327 : : return false; \
4328 : : } while(0)
4329 : :
4330 : : /*
4331 : : * If the path is not parameterized by the parent of the given relation,
4332 : : * it doesn't need reparameterization.
4333 : : */
4334 [ + + ]: 18612 : if (!path->param_info ||
4335 [ + - + + ]: 18408 : !bms_overlap(PATH_REQ_OUTER(path), child_rel->top_parent_relids))
4336 : 492 : return true;
4337 : :
4338 : : /*
4339 : : * Check that the path type is one that reparameterize_path_by_child() can
4340 : : * handle, and recursively check subpaths.
4341 : : */
4342 [ + + + + : 18120 : switch (nodeTag(path))
+ - + + -
+ - - ]
4343 : : {
4344 : 12156 : case T_Path:
4345 : : case T_IndexPath:
4346 : 12156 : break;
4347 : :
4348 : 24 : case T_BitmapHeapPath:
4349 : : {
4350 : 24 : BitmapHeapPath *bhpath = (BitmapHeapPath *) path;
4351 : :
4352 [ - + ]: 24 : REJECT_IF_PATH_NOT_REPARAMETERIZABLE(bhpath->bitmapqual);
4353 : : }
4354 : 24 : break;
4355 : :
4356 : 12 : case T_BitmapAndPath:
4357 : : {
4358 : 12 : BitmapAndPath *bapath = (BitmapAndPath *) path;
4359 : :
4360 [ - + ]: 12 : REJECT_IF_PATH_LIST_NOT_REPARAMETERIZABLE(bapath->bitmapquals);
4361 : : }
4362 : 12 : break;
4363 : :
4364 : 12 : case T_BitmapOrPath:
4365 : : {
4366 : 12 : BitmapOrPath *bopath = (BitmapOrPath *) path;
4367 : :
4368 [ - + ]: 12 : REJECT_IF_PATH_LIST_NOT_REPARAMETERIZABLE(bopath->bitmapquals);
4369 : : }
4370 : 12 : break;
4371 : :
4372 : 74 : case T_ForeignPath:
4373 : : {
4374 : 74 : ForeignPath *fpath = (ForeignPath *) path;
4375 : :
4376 [ - + ]: 74 : if (fpath->fdw_outerpath)
536 tgl@sss.pgh.pa.us 4377 [ # # ]:UBC 0 : REJECT_IF_PATH_NOT_REPARAMETERIZABLE(fpath->fdw_outerpath);
4378 : : }
536 tgl@sss.pgh.pa.us 4379 :CBC 74 : break;
4380 : :
536 tgl@sss.pgh.pa.us 4381 :UBC 0 : case T_CustomPath:
4382 : : {
4383 : 0 : CustomPath *cpath = (CustomPath *) path;
4384 : :
4385 [ # # ]: 0 : REJECT_IF_PATH_LIST_NOT_REPARAMETERIZABLE(cpath->custom_paths);
4386 : : }
4387 : 0 : break;
4388 : :
536 tgl@sss.pgh.pa.us 4389 :CBC 624 : case T_NestPath:
4390 : : case T_MergePath:
4391 : : case T_HashPath:
4392 : : {
4393 : 624 : JoinPath *jpath = (JoinPath *) path;
4394 : :
4395 [ - + ]: 624 : REJECT_IF_PATH_NOT_REPARAMETERIZABLE(jpath->outerjoinpath);
4396 [ - + ]: 624 : REJECT_IF_PATH_NOT_REPARAMETERIZABLE(jpath->innerjoinpath);
4397 : : }
4398 : 624 : break;
4399 : :
4400 : 96 : case T_AppendPath:
4401 : : {
4402 : 96 : AppendPath *apath = (AppendPath *) path;
4403 : :
4404 [ - + ]: 96 : REJECT_IF_PATH_LIST_NOT_REPARAMETERIZABLE(apath->subpaths);
4405 : : }
4406 : 96 : break;
4407 : :
536 tgl@sss.pgh.pa.us 4408 :UBC 0 : case T_MaterialPath:
4409 : : {
4410 : 0 : MaterialPath *mpath = (MaterialPath *) path;
4411 : :
4412 [ # # ]: 0 : REJECT_IF_PATH_NOT_REPARAMETERIZABLE(mpath->subpath);
4413 : : }
4414 : 0 : break;
4415 : :
536 tgl@sss.pgh.pa.us 4416 :CBC 5122 : case T_MemoizePath:
4417 : : {
4418 : 5122 : MemoizePath *mpath = (MemoizePath *) path;
4419 : :
4420 [ - + ]: 5122 : REJECT_IF_PATH_NOT_REPARAMETERIZABLE(mpath->subpath);
4421 : : }
4422 : 5122 : break;
4423 : :
536 tgl@sss.pgh.pa.us 4424 :UBC 0 : case T_GatherPath:
4425 : : {
4426 : 0 : GatherPath *gpath = (GatherPath *) path;
4427 : :
4428 [ # # ]: 0 : REJECT_IF_PATH_NOT_REPARAMETERIZABLE(gpath->subpath);
4429 : : }
4430 : 0 : break;
4431 : :
4432 : 0 : default:
4433 : : /* We don't know how to reparameterize this path. */
4434 : 0 : return false;
4435 : : }
4436 : :
536 tgl@sss.pgh.pa.us 4437 :CBC 18120 : return true;
4438 : : }
4439 : :
4440 : : /*
4441 : : * reparameterize_pathlist_by_child
4442 : : * Helper function to reparameterize a list of paths by given child rel.
4443 : : *
4444 : : * Returns NIL to indicate failure, so pathlist had better not be NIL.
4445 : : */
4446 : : static List *
2892 rhaas@postgresql.org 4447 : 36 : reparameterize_pathlist_by_child(PlannerInfo *root,
4448 : : List *pathlist,
4449 : : RelOptInfo *child_rel)
4450 : : {
4451 : : ListCell *lc;
4452 : 36 : List *result = NIL;
4453 : :
4454 [ + - + + : 108 : foreach(lc, pathlist)
+ + ]
4455 : : {
4456 : 72 : Path *path = reparameterize_path_by_child(root, lfirst(lc),
4457 : : child_rel);
4458 : :
4459 [ - + ]: 72 : if (path == NULL)
4460 : : {
2892 rhaas@postgresql.org 4461 :UBC 0 : list_free(result);
4462 : 0 : return NIL;
4463 : : }
4464 : :
2892 rhaas@postgresql.org 4465 :CBC 72 : result = lappend(result, path);
4466 : : }
4467 : :
4468 : 36 : return result;
4469 : : }
4470 : :
4471 : : /*
4472 : : * pathlist_is_reparameterizable_by_child
4473 : : * Helper function to check if a list of paths can be reparameterized.
4474 : : */
4475 : : static bool
536 tgl@sss.pgh.pa.us 4476 : 120 : pathlist_is_reparameterizable_by_child(List *pathlist, RelOptInfo *child_rel)
4477 : : {
4478 : : ListCell *lc;
4479 : :
4480 [ + - + + : 360 : foreach(lc, pathlist)
+ + ]
4481 : : {
4482 : 240 : Path *path = (Path *) lfirst(lc);
4483 : :
4484 [ - + ]: 240 : if (!path_is_reparameterizable_by_child(path, child_rel))
536 tgl@sss.pgh.pa.us 4485 :UBC 0 : return false;
4486 : : }
4487 : :
536 tgl@sss.pgh.pa.us 4488 :CBC 120 : return true;
4489 : : }
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