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pathnode.c
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1 /*-------------------------------------------------------------------------
2  *
3  * pathnode.c
4  * Routines to manipulate pathlists and create path nodes
5  *
6  * Portions Copyright (c) 1996-2024, 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 */
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 List *translate_sub_tlist(List *tlist, int relid);
50 static int append_total_cost_compare(const ListCell *a, const ListCell *b);
51 static int append_startup_cost_compare(const ListCell *a, const ListCell *b);
53  List *pathlist,
54  RelOptInfo *child_rel);
55 static bool pathlist_is_reparameterizable_by_child(List *pathlist,
56  RelOptInfo *child_rel);
57 
58 
59 /*****************************************************************************
60  * MISC. PATH UTILITIES
61  *****************************************************************************/
62 
63 /*
64  * compare_path_costs
65  * Return -1, 0, or +1 according as path1 is cheaper, the same cost,
66  * or more expensive than path2 for the specified criterion.
67  */
68 int
69 compare_path_costs(Path *path1, Path *path2, CostSelector criterion)
70 {
71  if (criterion == STARTUP_COST)
72  {
73  if (path1->startup_cost < path2->startup_cost)
74  return -1;
75  if (path1->startup_cost > path2->startup_cost)
76  return +1;
77 
78  /*
79  * If paths have the same startup cost (not at all unlikely), order
80  * them by total cost.
81  */
82  if (path1->total_cost < path2->total_cost)
83  return -1;
84  if (path1->total_cost > path2->total_cost)
85  return +1;
86  }
87  else
88  {
89  if (path1->total_cost < path2->total_cost)
90  return -1;
91  if (path1->total_cost > path2->total_cost)
92  return +1;
93 
94  /*
95  * If paths have the same total cost, order them by startup cost.
96  */
97  if (path1->startup_cost < path2->startup_cost)
98  return -1;
99  if (path1->startup_cost > path2->startup_cost)
100  return +1;
101  }
102  return 0;
103 }
104 
105 /*
106  * compare_fractional_path_costs
107  * Return -1, 0, or +1 according as path1 is cheaper, the same cost,
108  * or more expensive than path2 for fetching the specified fraction
109  * of the total tuples.
110  *
111  * If fraction is <= 0 or > 1, we interpret it as 1, ie, we select the
112  * path with the cheaper total_cost.
113  */
114 int
116  double fraction)
117 {
118  Cost cost1,
119  cost2;
120 
121  if (fraction <= 0.0 || fraction >= 1.0)
122  return compare_path_costs(path1, path2, TOTAL_COST);
123  cost1 = path1->startup_cost +
124  fraction * (path1->total_cost - path1->startup_cost);
125  cost2 = path2->startup_cost +
126  fraction * (path2->total_cost - path2->startup_cost);
127  if (cost1 < cost2)
128  return -1;
129  if (cost1 > cost2)
130  return +1;
131  return 0;
132 }
133 
134 /*
135  * compare_path_costs_fuzzily
136  * Compare the costs of two paths to see if either can be said to
137  * dominate the other.
138  *
139  * We use fuzzy comparisons so that add_path() can avoid keeping both of
140  * a pair of paths that really have insignificantly different cost.
141  *
142  * The fuzz_factor argument must be 1.0 plus delta, where delta is the
143  * fraction of the smaller cost that is considered to be a significant
144  * difference. For example, fuzz_factor = 1.01 makes the fuzziness limit
145  * be 1% of the smaller cost.
146  *
147  * The two paths are said to have "equal" costs if both startup and total
148  * costs are fuzzily the same. Path1 is said to be better than path2 if
149  * it has fuzzily better startup cost and fuzzily no worse total cost,
150  * or if it has fuzzily better total cost and fuzzily no worse startup cost.
151  * Path2 is better than path1 if the reverse holds. Finally, if one path
152  * is fuzzily better than the other on startup cost and fuzzily worse on
153  * total cost, we just say that their costs are "different", since neither
154  * dominates the other across the whole performance spectrum.
155  *
156  * This function also enforces a policy rule that paths for which the relevant
157  * one of parent->consider_startup and parent->consider_param_startup is false
158  * cannot survive comparisons solely on the grounds of good startup cost, so
159  * we never return COSTS_DIFFERENT when that is true for the total-cost loser.
160  * (But if total costs are fuzzily equal, we compare startup costs anyway,
161  * in hopes of eliminating one path or the other.)
162  */
163 static PathCostComparison
164 compare_path_costs_fuzzily(Path *path1, Path *path2, double fuzz_factor)
165 {
166 #define CONSIDER_PATH_STARTUP_COST(p) \
167  ((p)->param_info == NULL ? (p)->parent->consider_startup : (p)->parent->consider_param_startup)
168 
169  /*
170  * Check total cost first since it's more likely to be different; many
171  * paths have zero startup cost.
172  */
173  if (path1->total_cost > path2->total_cost * fuzz_factor)
174  {
175  /* path1 fuzzily worse on total cost */
176  if (CONSIDER_PATH_STARTUP_COST(path1) &&
177  path2->startup_cost > path1->startup_cost * fuzz_factor)
178  {
179  /* ... but path2 fuzzily worse on startup, so DIFFERENT */
180  return COSTS_DIFFERENT;
181  }
182  /* else path2 dominates */
183  return COSTS_BETTER2;
184  }
185  if (path2->total_cost > path1->total_cost * fuzz_factor)
186  {
187  /* path2 fuzzily worse on total cost */
188  if (CONSIDER_PATH_STARTUP_COST(path2) &&
189  path1->startup_cost > path2->startup_cost * fuzz_factor)
190  {
191  /* ... but path1 fuzzily worse on startup, so DIFFERENT */
192  return COSTS_DIFFERENT;
193  }
194  /* else path1 dominates */
195  return COSTS_BETTER1;
196  }
197  /* fuzzily the same on total cost ... */
198  if (path1->startup_cost > path2->startup_cost * fuzz_factor)
199  {
200  /* ... but path1 fuzzily worse on startup, so path2 wins */
201  return COSTS_BETTER2;
202  }
203  if (path2->startup_cost > path1->startup_cost * fuzz_factor)
204  {
205  /* ... but path2 fuzzily worse on startup, so path1 wins */
206  return COSTS_BETTER1;
207  }
208  /* fuzzily the same on both costs */
209  return COSTS_EQUAL;
210 
211 #undef CONSIDER_PATH_STARTUP_COST
212 }
213 
214 /*
215  * set_cheapest
216  * Find the minimum-cost paths from among a relation's paths,
217  * and save them in the rel's cheapest-path fields.
218  *
219  * cheapest_total_path is normally the cheapest-total-cost unparameterized
220  * path; but if there are no unparameterized paths, we assign it to be the
221  * best (cheapest least-parameterized) parameterized path. However, only
222  * unparameterized paths are considered candidates for cheapest_startup_path,
223  * so that will be NULL if there are no unparameterized paths.
224  *
225  * The cheapest_parameterized_paths list collects all parameterized paths
226  * that have survived the add_path() tournament for this relation. (Since
227  * add_path ignores pathkeys for a parameterized path, these will be paths
228  * that have best cost or best row count for their parameterization. We
229  * may also have both a parallel-safe and a non-parallel-safe path in some
230  * cases for the same parameterization in some cases, but this should be
231  * relatively rare since, most typically, all paths for the same relation
232  * will be parallel-safe or none of them will.)
233  *
234  * cheapest_parameterized_paths always includes the cheapest-total
235  * unparameterized path, too, if there is one; the users of that list find
236  * it more convenient if that's included.
237  *
238  * This is normally called only after we've finished constructing the path
239  * list for the rel node.
240  */
241 void
243 {
244  Path *cheapest_startup_path;
245  Path *cheapest_total_path;
246  Path *best_param_path;
247  List *parameterized_paths;
248  ListCell *p;
249 
250  Assert(IsA(parent_rel, RelOptInfo));
251 
252  if (parent_rel->pathlist == NIL)
253  elog(ERROR, "could not devise a query plan for the given query");
254 
255  cheapest_startup_path = cheapest_total_path = best_param_path = NULL;
256  parameterized_paths = NIL;
257 
258  foreach(p, parent_rel->pathlist)
259  {
260  Path *path = (Path *) lfirst(p);
261  int cmp;
262 
263  if (path->param_info)
264  {
265  /* Parameterized path, so add it to parameterized_paths */
266  parameterized_paths = lappend(parameterized_paths, path);
267 
268  /*
269  * If we have an unparameterized cheapest-total, we no longer care
270  * about finding the best parameterized path, so move on.
271  */
272  if (cheapest_total_path)
273  continue;
274 
275  /*
276  * Otherwise, track the best parameterized path, which is the one
277  * with least total cost among those of the minimum
278  * parameterization.
279  */
280  if (best_param_path == NULL)
281  best_param_path = path;
282  else
283  {
284  switch (bms_subset_compare(PATH_REQ_OUTER(path),
285  PATH_REQ_OUTER(best_param_path)))
286  {
287  case BMS_EQUAL:
288  /* keep the cheaper one */
289  if (compare_path_costs(path, best_param_path,
290  TOTAL_COST) < 0)
291  best_param_path = path;
292  break;
293  case BMS_SUBSET1:
294  /* new path is less-parameterized */
295  best_param_path = path;
296  break;
297  case BMS_SUBSET2:
298  /* old path is less-parameterized, keep it */
299  break;
300  case BMS_DIFFERENT:
301 
302  /*
303  * This means that neither path has the least possible
304  * parameterization for the rel. We'll sit on the old
305  * path until something better comes along.
306  */
307  break;
308  }
309  }
310  }
311  else
312  {
313  /* Unparameterized path, so consider it for cheapest slots */
314  if (cheapest_total_path == NULL)
315  {
316  cheapest_startup_path = cheapest_total_path = path;
317  continue;
318  }
319 
320  /*
321  * If we find two paths of identical costs, try to keep the
322  * better-sorted one. The paths might have unrelated sort
323  * orderings, in which case we can only guess which might be
324  * better to keep, but if one is superior then we definitely
325  * should keep that one.
326  */
327  cmp = compare_path_costs(cheapest_startup_path, path, STARTUP_COST);
328  if (cmp > 0 ||
329  (cmp == 0 &&
330  compare_pathkeys(cheapest_startup_path->pathkeys,
331  path->pathkeys) == PATHKEYS_BETTER2))
332  cheapest_startup_path = path;
333 
334  cmp = compare_path_costs(cheapest_total_path, path, TOTAL_COST);
335  if (cmp > 0 ||
336  (cmp == 0 &&
337  compare_pathkeys(cheapest_total_path->pathkeys,
338  path->pathkeys) == PATHKEYS_BETTER2))
339  cheapest_total_path = path;
340  }
341  }
342 
343  /* Add cheapest unparameterized path, if any, to parameterized_paths */
344  if (cheapest_total_path)
345  parameterized_paths = lcons(cheapest_total_path, parameterized_paths);
346 
347  /*
348  * If there is no unparameterized path, use the best parameterized path as
349  * cheapest_total_path (but not as cheapest_startup_path).
350  */
351  if (cheapest_total_path == NULL)
352  cheapest_total_path = best_param_path;
353  Assert(cheapest_total_path != NULL);
354 
355  parent_rel->cheapest_startup_path = cheapest_startup_path;
356  parent_rel->cheapest_total_path = cheapest_total_path;
357  parent_rel->cheapest_unique_path = NULL; /* computed only if needed */
358  parent_rel->cheapest_parameterized_paths = parameterized_paths;
359 }
360 
361 /*
362  * add_path
363  * Consider a potential implementation path for the specified parent rel,
364  * and add it to the rel's pathlist if it is worthy of consideration.
365  * A path is worthy if it has a better sort order (better pathkeys) or
366  * cheaper cost (on either dimension), or generates fewer rows, than any
367  * existing path that has the same or superset parameterization rels.
368  * We also consider parallel-safe paths more worthy than others.
369  *
370  * We also remove from the rel's pathlist any old paths that are dominated
371  * by new_path --- that is, new_path is cheaper, at least as well ordered,
372  * generates no more rows, requires no outer rels not required by the old
373  * path, and is no less parallel-safe.
374  *
375  * In most cases, a path with a superset parameterization will generate
376  * fewer rows (since it has more join clauses to apply), so that those two
377  * figures of merit move in opposite directions; this means that a path of
378  * one parameterization can seldom dominate a path of another. But such
379  * cases do arise, so we make the full set of checks anyway.
380  *
381  * There are two policy decisions embedded in this function, along with
382  * its sibling add_path_precheck. First, we treat all parameterized paths
383  * as having NIL pathkeys, so that they cannot win comparisons on the
384  * basis of sort order. This is to reduce the number of parameterized
385  * paths that are kept; see discussion in src/backend/optimizer/README.
386  *
387  * Second, we only consider cheap startup cost to be interesting if
388  * parent_rel->consider_startup is true for an unparameterized path, or
389  * parent_rel->consider_param_startup is true for a parameterized one.
390  * Again, this allows discarding useless paths sooner.
391  *
392  * The pathlist is kept sorted by total_cost, with cheaper paths
393  * at the front. Within this routine, that's simply a speed hack:
394  * doing it that way makes it more likely that we will reject an inferior
395  * path after a few comparisons, rather than many comparisons.
396  * However, add_path_precheck relies on this ordering to exit early
397  * when possible.
398  *
399  * NOTE: discarded Path objects are immediately pfree'd to reduce planner
400  * memory consumption. We dare not try to free the substructure of a Path,
401  * since much of it may be shared with other Paths or the query tree itself;
402  * but just recycling discarded Path nodes is a very useful savings in
403  * a large join tree. We can recycle the List nodes of pathlist, too.
404  *
405  * As noted in optimizer/README, deleting a previously-accepted Path is
406  * safe because we know that Paths of this rel cannot yet be referenced
407  * from any other rel, such as a higher-level join. However, in some cases
408  * it is possible that a Path is referenced by another Path for its own
409  * rel; we must not delete such a Path, even if it is dominated by the new
410  * Path. Currently this occurs only for IndexPath objects, which may be
411  * referenced as children of BitmapHeapPaths as well as being paths in
412  * their own right. Hence, we don't pfree IndexPaths when rejecting them.
413  *
414  * 'parent_rel' is the relation entry to which the path corresponds.
415  * 'new_path' is a potential path for parent_rel.
416  *
417  * Returns nothing, but modifies parent_rel->pathlist.
418  */
419 void
420 add_path(RelOptInfo *parent_rel, Path *new_path)
421 {
422  bool accept_new = true; /* unless we find a superior old path */
423  int insert_at = 0; /* where to insert new item */
424  List *new_path_pathkeys;
425  ListCell *p1;
426 
427  /*
428  * This is a convenient place to check for query cancel --- no part of the
429  * planner goes very long without calling add_path().
430  */
432 
433  /* Pretend parameterized paths have no pathkeys, per comment above */
434  new_path_pathkeys = new_path->param_info ? NIL : new_path->pathkeys;
435 
436  /*
437  * Loop to check proposed new path against old paths. Note it is possible
438  * for more than one old path to be tossed out because new_path dominates
439  * it.
440  */
441  foreach(p1, parent_rel->pathlist)
442  {
443  Path *old_path = (Path *) lfirst(p1);
444  bool remove_old = false; /* unless new proves superior */
445  PathCostComparison costcmp;
446  PathKeysComparison keyscmp;
447  BMS_Comparison outercmp;
448 
449  /*
450  * Do a fuzzy cost comparison with standard fuzziness limit.
451  */
452  costcmp = compare_path_costs_fuzzily(new_path, old_path,
454 
455  /*
456  * If the two paths compare differently for startup and total cost,
457  * then we want to keep both, and we can skip comparing pathkeys and
458  * required_outer rels. If they compare the same, proceed with the
459  * other comparisons. Row count is checked last. (We make the tests
460  * in this order because the cost comparison is most likely to turn
461  * out "different", and the pathkeys comparison next most likely. As
462  * explained above, row count very seldom makes a difference, so even
463  * though it's cheap to compare there's not much point in checking it
464  * earlier.)
465  */
466  if (costcmp != COSTS_DIFFERENT)
467  {
468  /* Similarly check to see if either dominates on pathkeys */
469  List *old_path_pathkeys;
470 
471  old_path_pathkeys = old_path->param_info ? NIL : old_path->pathkeys;
472  keyscmp = compare_pathkeys(new_path_pathkeys,
473  old_path_pathkeys);
474  if (keyscmp != PATHKEYS_DIFFERENT)
475  {
476  switch (costcmp)
477  {
478  case COSTS_EQUAL:
479  outercmp = bms_subset_compare(PATH_REQ_OUTER(new_path),
480  PATH_REQ_OUTER(old_path));
481  if (keyscmp == PATHKEYS_BETTER1)
482  {
483  if ((outercmp == BMS_EQUAL ||
484  outercmp == BMS_SUBSET1) &&
485  new_path->rows <= old_path->rows &&
486  new_path->parallel_safe >= old_path->parallel_safe)
487  remove_old = true; /* new dominates old */
488  }
489  else if (keyscmp == PATHKEYS_BETTER2)
490  {
491  if ((outercmp == BMS_EQUAL ||
492  outercmp == BMS_SUBSET2) &&
493  new_path->rows >= old_path->rows &&
494  new_path->parallel_safe <= old_path->parallel_safe)
495  accept_new = false; /* old dominates new */
496  }
497  else /* keyscmp == PATHKEYS_EQUAL */
498  {
499  if (outercmp == BMS_EQUAL)
500  {
501  /*
502  * Same pathkeys and outer rels, and fuzzily
503  * the same cost, so keep just one; to decide
504  * which, first check parallel-safety, then
505  * rows, then do a fuzzy cost comparison with
506  * very small fuzz limit. (We used to do an
507  * exact cost comparison, but that results in
508  * annoying platform-specific plan variations
509  * due to roundoff in the cost estimates.) If
510  * things are still tied, arbitrarily keep
511  * only the old path. Notice that we will
512  * keep only the old path even if the
513  * less-fuzzy comparison decides the startup
514  * and total costs compare differently.
515  */
516  if (new_path->parallel_safe >
517  old_path->parallel_safe)
518  remove_old = true; /* new dominates old */
519  else if (new_path->parallel_safe <
520  old_path->parallel_safe)
521  accept_new = false; /* old dominates new */
522  else if (new_path->rows < old_path->rows)
523  remove_old = true; /* new dominates old */
524  else if (new_path->rows > old_path->rows)
525  accept_new = false; /* old dominates new */
526  else if (compare_path_costs_fuzzily(new_path,
527  old_path,
528  1.0000000001) == COSTS_BETTER1)
529  remove_old = true; /* new dominates old */
530  else
531  accept_new = false; /* old equals or
532  * dominates new */
533  }
534  else if (outercmp == BMS_SUBSET1 &&
535  new_path->rows <= old_path->rows &&
536  new_path->parallel_safe >= old_path->parallel_safe)
537  remove_old = true; /* new dominates old */
538  else if (outercmp == BMS_SUBSET2 &&
539  new_path->rows >= old_path->rows &&
540  new_path->parallel_safe <= old_path->parallel_safe)
541  accept_new = false; /* old dominates new */
542  /* else different parameterizations, keep both */
543  }
544  break;
545  case COSTS_BETTER1:
546  if (keyscmp != PATHKEYS_BETTER2)
547  {
548  outercmp = bms_subset_compare(PATH_REQ_OUTER(new_path),
549  PATH_REQ_OUTER(old_path));
550  if ((outercmp == BMS_EQUAL ||
551  outercmp == BMS_SUBSET1) &&
552  new_path->rows <= old_path->rows &&
553  new_path->parallel_safe >= old_path->parallel_safe)
554  remove_old = true; /* new dominates old */
555  }
556  break;
557  case COSTS_BETTER2:
558  if (keyscmp != PATHKEYS_BETTER1)
559  {
560  outercmp = bms_subset_compare(PATH_REQ_OUTER(new_path),
561  PATH_REQ_OUTER(old_path));
562  if ((outercmp == BMS_EQUAL ||
563  outercmp == BMS_SUBSET2) &&
564  new_path->rows >= old_path->rows &&
565  new_path->parallel_safe <= old_path->parallel_safe)
566  accept_new = false; /* old dominates new */
567  }
568  break;
569  case COSTS_DIFFERENT:
570 
571  /*
572  * can't get here, but keep this case to keep compiler
573  * quiet
574  */
575  break;
576  }
577  }
578  }
579 
580  /*
581  * Remove current element from pathlist if dominated by new.
582  */
583  if (remove_old)
584  {
585  parent_rel->pathlist = foreach_delete_current(parent_rel->pathlist,
586  p1);
587 
588  /*
589  * Delete the data pointed-to by the deleted cell, if possible
590  */
591  if (!IsA(old_path, IndexPath))
592  pfree(old_path);
593  }
594  else
595  {
596  /* new belongs after this old path if it has cost >= old's */
597  if (new_path->total_cost >= old_path->total_cost)
598  insert_at = foreach_current_index(p1) + 1;
599  }
600 
601  /*
602  * If we found an old path that dominates new_path, we can quit
603  * scanning the pathlist; we will not add new_path, and we assume
604  * new_path cannot dominate any other elements of the pathlist.
605  */
606  if (!accept_new)
607  break;
608  }
609 
610  if (accept_new)
611  {
612  /* Accept the new path: insert it at proper place in pathlist */
613  parent_rel->pathlist =
614  list_insert_nth(parent_rel->pathlist, insert_at, new_path);
615  }
616  else
617  {
618  /* Reject and recycle the new path */
619  if (!IsA(new_path, IndexPath))
620  pfree(new_path);
621  }
622 }
623 
624 /*
625  * add_path_precheck
626  * Check whether a proposed new path could possibly get accepted.
627  * We assume we know the path's pathkeys and parameterization accurately,
628  * and have lower bounds for its costs.
629  *
630  * Note that we do not know the path's rowcount, since getting an estimate for
631  * that is too expensive to do before prechecking. We assume here that paths
632  * of a superset parameterization will generate fewer rows; if that holds,
633  * then paths with different parameterizations cannot dominate each other
634  * and so we can simply ignore existing paths of another parameterization.
635  * (In the infrequent cases where that rule of thumb fails, add_path will
636  * get rid of the inferior path.)
637  *
638  * At the time this is called, we haven't actually built a Path structure,
639  * so the required information has to be passed piecemeal.
640  */
641 bool
643  Cost startup_cost, Cost total_cost,
644  List *pathkeys, Relids required_outer)
645 {
646  List *new_path_pathkeys;
647  bool consider_startup;
648  ListCell *p1;
649 
650  /* Pretend parameterized paths have no pathkeys, per add_path policy */
651  new_path_pathkeys = required_outer ? NIL : pathkeys;
652 
653  /* Decide whether new path's startup cost is interesting */
654  consider_startup = required_outer ? parent_rel->consider_param_startup : parent_rel->consider_startup;
655 
656  foreach(p1, parent_rel->pathlist)
657  {
658  Path *old_path = (Path *) lfirst(p1);
659  PathKeysComparison keyscmp;
660 
661  /*
662  * We are looking for an old_path with the same parameterization (and
663  * by assumption the same rowcount) that dominates the new path on
664  * pathkeys as well as both cost metrics. If we find one, we can
665  * reject the new path.
666  *
667  * Cost comparisons here should match compare_path_costs_fuzzily.
668  */
669  if (total_cost > old_path->total_cost * STD_FUZZ_FACTOR)
670  {
671  /* new path can win on startup cost only if consider_startup */
672  if (startup_cost > old_path->startup_cost * STD_FUZZ_FACTOR ||
673  !consider_startup)
674  {
675  /* new path loses on cost, so check pathkeys... */
676  List *old_path_pathkeys;
677 
678  old_path_pathkeys = old_path->param_info ? NIL : old_path->pathkeys;
679  keyscmp = compare_pathkeys(new_path_pathkeys,
680  old_path_pathkeys);
681  if (keyscmp == PATHKEYS_EQUAL ||
682  keyscmp == PATHKEYS_BETTER2)
683  {
684  /* new path does not win on pathkeys... */
685  if (bms_equal(required_outer, PATH_REQ_OUTER(old_path)))
686  {
687  /* Found an old path that dominates the new one */
688  return false;
689  }
690  }
691  }
692  }
693  else
694  {
695  /*
696  * Since the pathlist is sorted by total_cost, we can stop looking
697  * once we reach a path with a total_cost larger than the new
698  * path's.
699  */
700  break;
701  }
702  }
703 
704  return true;
705 }
706 
707 /*
708  * add_partial_path
709  * Like add_path, our goal here is to consider whether a path is worthy
710  * of being kept around, but the considerations here are a bit different.
711  * A partial path is one which can be executed in any number of workers in
712  * parallel such that each worker will generate a subset of the path's
713  * overall result.
714  *
715  * As in add_path, the partial_pathlist is kept sorted with the cheapest
716  * total path in front. This is depended on by multiple places, which
717  * just take the front entry as the cheapest path without searching.
718  *
719  * We don't generate parameterized partial paths for several reasons. Most
720  * importantly, they're not safe to execute, because there's nothing to
721  * make sure that a parallel scan within the parameterized portion of the
722  * plan is running with the same value in every worker at the same time.
723  * Fortunately, it seems unlikely to be worthwhile anyway, because having
724  * each worker scan the entire outer relation and a subset of the inner
725  * relation will generally be a terrible plan. The inner (parameterized)
726  * side of the plan will be small anyway. There could be rare cases where
727  * this wins big - e.g. if join order constraints put a 1-row relation on
728  * the outer side of the topmost join with a parameterized plan on the inner
729  * side - but we'll have to be content not to handle such cases until
730  * somebody builds an executor infrastructure that can cope with them.
731  *
732  * Because we don't consider parameterized paths here, we also don't
733  * need to consider the row counts as a measure of quality: every path will
734  * produce the same number of rows. Neither do we need to consider startup
735  * costs: parallelism is only used for plans that will be run to completion.
736  * Therefore, this routine is much simpler than add_path: it needs to
737  * consider only pathkeys and total cost.
738  *
739  * As with add_path, we pfree paths that are found to be dominated by
740  * another partial path; this requires that there be no other references to
741  * such paths yet. Hence, GatherPaths must not be created for a rel until
742  * we're done creating all partial paths for it. Unlike add_path, we don't
743  * take an exception for IndexPaths as partial index paths won't be
744  * referenced by partial BitmapHeapPaths.
745  */
746 void
747 add_partial_path(RelOptInfo *parent_rel, Path *new_path)
748 {
749  bool accept_new = true; /* unless we find a superior old path */
750  int insert_at = 0; /* where to insert new item */
751  ListCell *p1;
752 
753  /* Check for query cancel. */
755 
756  /* Path to be added must be parallel safe. */
757  Assert(new_path->parallel_safe);
758 
759  /* Relation should be OK for parallelism, too. */
760  Assert(parent_rel->consider_parallel);
761 
762  /*
763  * As in add_path, throw out any paths which are dominated by the new
764  * path, but throw out the new path if some existing path dominates it.
765  */
766  foreach(p1, parent_rel->partial_pathlist)
767  {
768  Path *old_path = (Path *) lfirst(p1);
769  bool remove_old = false; /* unless new proves superior */
770  PathKeysComparison keyscmp;
771 
772  /* Compare pathkeys. */
773  keyscmp = compare_pathkeys(new_path->pathkeys, old_path->pathkeys);
774 
775  /* Unless pathkeys are incompatible, keep just one of the two paths. */
776  if (keyscmp != PATHKEYS_DIFFERENT)
777  {
778  if (new_path->total_cost > old_path->total_cost * STD_FUZZ_FACTOR)
779  {
780  /* New path costs more; keep it only if pathkeys are better. */
781  if (keyscmp != PATHKEYS_BETTER1)
782  accept_new = false;
783  }
784  else if (old_path->total_cost > new_path->total_cost
785  * STD_FUZZ_FACTOR)
786  {
787  /* Old path costs more; keep it only if pathkeys are better. */
788  if (keyscmp != PATHKEYS_BETTER2)
789  remove_old = true;
790  }
791  else if (keyscmp == PATHKEYS_BETTER1)
792  {
793  /* Costs are about the same, new path has better pathkeys. */
794  remove_old = true;
795  }
796  else if (keyscmp == PATHKEYS_BETTER2)
797  {
798  /* Costs are about the same, old path has better pathkeys. */
799  accept_new = false;
800  }
801  else if (old_path->total_cost > new_path->total_cost * 1.0000000001)
802  {
803  /* Pathkeys are the same, and the old path costs more. */
804  remove_old = true;
805  }
806  else
807  {
808  /*
809  * Pathkeys are the same, and new path isn't materially
810  * cheaper.
811  */
812  accept_new = false;
813  }
814  }
815 
816  /*
817  * Remove current element from partial_pathlist if dominated by new.
818  */
819  if (remove_old)
820  {
821  parent_rel->partial_pathlist =
822  foreach_delete_current(parent_rel->partial_pathlist, p1);
823  pfree(old_path);
824  }
825  else
826  {
827  /* new belongs after this old path if it has cost >= old's */
828  if (new_path->total_cost >= old_path->total_cost)
829  insert_at = foreach_current_index(p1) + 1;
830  }
831 
832  /*
833  * If we found an old path that dominates new_path, we can quit
834  * scanning the partial_pathlist; we will not add new_path, and we
835  * assume new_path cannot dominate any later path.
836  */
837  if (!accept_new)
838  break;
839  }
840 
841  if (accept_new)
842  {
843  /* Accept the new path: insert it at proper place */
844  parent_rel->partial_pathlist =
845  list_insert_nth(parent_rel->partial_pathlist, insert_at, new_path);
846  }
847  else
848  {
849  /* Reject and recycle the new path */
850  pfree(new_path);
851  }
852 }
853 
854 /*
855  * add_partial_path_precheck
856  * Check whether a proposed new partial path could possibly get accepted.
857  *
858  * Unlike add_path_precheck, we can ignore startup cost and parameterization,
859  * since they don't matter for partial paths (see add_partial_path). But
860  * we do want to make sure we don't add a partial path if there's already
861  * a complete path that dominates it, since in that case the proposed path
862  * is surely a loser.
863  */
864 bool
865 add_partial_path_precheck(RelOptInfo *parent_rel, Cost total_cost,
866  List *pathkeys)
867 {
868  ListCell *p1;
869 
870  /*
871  * Our goal here is twofold. First, we want to find out whether this path
872  * is clearly inferior to some existing partial path. If so, we want to
873  * reject it immediately. Second, we want to find out whether this path
874  * is clearly superior to some existing partial path -- at least, modulo
875  * final cost computations. If so, we definitely want to consider it.
876  *
877  * Unlike add_path(), we always compare pathkeys here. This is because we
878  * expect partial_pathlist to be very short, and getting a definitive
879  * answer at this stage avoids the need to call add_path_precheck.
880  */
881  foreach(p1, parent_rel->partial_pathlist)
882  {
883  Path *old_path = (Path *) lfirst(p1);
884  PathKeysComparison keyscmp;
885 
886  keyscmp = compare_pathkeys(pathkeys, old_path->pathkeys);
887  if (keyscmp != PATHKEYS_DIFFERENT)
888  {
889  if (total_cost > old_path->total_cost * STD_FUZZ_FACTOR &&
890  keyscmp != PATHKEYS_BETTER1)
891  return false;
892  if (old_path->total_cost > total_cost * STD_FUZZ_FACTOR &&
893  keyscmp != PATHKEYS_BETTER2)
894  return true;
895  }
896  }
897 
898  /*
899  * This path is neither clearly inferior to an existing partial path nor
900  * clearly good enough that it might replace one. Compare it to
901  * non-parallel plans. If it loses even before accounting for the cost of
902  * the Gather node, we should definitely reject it.
903  *
904  * Note that we pass the total_cost to add_path_precheck twice. This is
905  * because it's never advantageous to consider the startup cost of a
906  * partial path; the resulting plans, if run in parallel, will be run to
907  * completion.
908  */
909  if (!add_path_precheck(parent_rel, total_cost, total_cost, pathkeys,
910  NULL))
911  return false;
912 
913  return true;
914 }
915 
916 
917 /*****************************************************************************
918  * PATH NODE CREATION ROUTINES
919  *****************************************************************************/
920 
921 /*
922  * create_seqscan_path
923  * Creates a path corresponding to a sequential scan, returning the
924  * pathnode.
925  */
926 Path *
928  Relids required_outer, int parallel_workers)
929 {
930  Path *pathnode = makeNode(Path);
931 
932  pathnode->pathtype = T_SeqScan;
933  pathnode->parent = rel;
934  pathnode->pathtarget = rel->reltarget;
935  pathnode->param_info = get_baserel_parampathinfo(root, rel,
936  required_outer);
937  pathnode->parallel_aware = (parallel_workers > 0);
938  pathnode->parallel_safe = rel->consider_parallel;
939  pathnode->parallel_workers = parallel_workers;
940  pathnode->pathkeys = NIL; /* seqscan has unordered result */
941 
942  cost_seqscan(pathnode, root, rel, pathnode->param_info);
943 
944  return pathnode;
945 }
946 
947 /*
948  * create_samplescan_path
949  * Creates a path node for a sampled table scan.
950  */
951 Path *
953 {
954  Path *pathnode = makeNode(Path);
955 
956  pathnode->pathtype = T_SampleScan;
957  pathnode->parent = rel;
958  pathnode->pathtarget = rel->reltarget;
959  pathnode->param_info = get_baserel_parampathinfo(root, rel,
960  required_outer);
961  pathnode->parallel_aware = false;
962  pathnode->parallel_safe = rel->consider_parallel;
963  pathnode->parallel_workers = 0;
964  pathnode->pathkeys = NIL; /* samplescan has unordered result */
965 
966  cost_samplescan(pathnode, root, rel, pathnode->param_info);
967 
968  return pathnode;
969 }
970 
971 /*
972  * create_index_path
973  * Creates a path node for an index scan.
974  *
975  * 'index' is a usable index.
976  * 'indexclauses' is a list of IndexClause nodes representing clauses
977  * to be enforced as qual conditions in the scan.
978  * 'indexorderbys' is a list of bare expressions (no RestrictInfos)
979  * to be used as index ordering operators in the scan.
980  * 'indexorderbycols' is an integer list of index column numbers (zero based)
981  * the ordering operators can be used with.
982  * 'pathkeys' describes the ordering of the path.
983  * 'indexscandir' is either ForwardScanDirection or BackwardScanDirection.
984  * 'indexonly' is true if an index-only scan is wanted.
985  * 'required_outer' is the set of outer relids for a parameterized path.
986  * 'loop_count' is the number of repetitions of the indexscan to factor into
987  * estimates of caching behavior.
988  * 'partial_path' is true if constructing a parallel index scan path.
989  *
990  * Returns the new path node.
991  */
992 IndexPath *
995  List *indexclauses,
996  List *indexorderbys,
997  List *indexorderbycols,
998  List *pathkeys,
999  ScanDirection indexscandir,
1000  bool indexonly,
1001  Relids required_outer,
1002  double loop_count,
1003  bool partial_path)
1004 {
1005  IndexPath *pathnode = makeNode(IndexPath);
1006  RelOptInfo *rel = index->rel;
1007 
1008  pathnode->path.pathtype = indexonly ? T_IndexOnlyScan : T_IndexScan;
1009  pathnode->path.parent = rel;
1010  pathnode->path.pathtarget = rel->reltarget;
1011  pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1012  required_outer);
1013  pathnode->path.parallel_aware = false;
1014  pathnode->path.parallel_safe = rel->consider_parallel;
1015  pathnode->path.parallel_workers = 0;
1016  pathnode->path.pathkeys = pathkeys;
1017 
1018  pathnode->indexinfo = index;
1019  pathnode->indexclauses = indexclauses;
1020  pathnode->indexorderbys = indexorderbys;
1021  pathnode->indexorderbycols = indexorderbycols;
1022  pathnode->indexscandir = indexscandir;
1023 
1024  cost_index(pathnode, root, loop_count, partial_path);
1025 
1026  return pathnode;
1027 }
1028 
1029 /*
1030  * create_bitmap_heap_path
1031  * Creates a path node for a bitmap scan.
1032  *
1033  * 'bitmapqual' is a tree of IndexPath, BitmapAndPath, and BitmapOrPath nodes.
1034  * 'required_outer' is the set of outer relids for a parameterized path.
1035  * 'loop_count' is the number of repetitions of the indexscan to factor into
1036  * estimates of caching behavior.
1037  *
1038  * loop_count should match the value used when creating the component
1039  * IndexPaths.
1040  */
1043  RelOptInfo *rel,
1044  Path *bitmapqual,
1045  Relids required_outer,
1046  double loop_count,
1047  int parallel_degree)
1048 {
1049  BitmapHeapPath *pathnode = makeNode(BitmapHeapPath);
1050 
1051  pathnode->path.pathtype = T_BitmapHeapScan;
1052  pathnode->path.parent = rel;
1053  pathnode->path.pathtarget = rel->reltarget;
1054  pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1055  required_outer);
1056  pathnode->path.parallel_aware = (parallel_degree > 0);
1057  pathnode->path.parallel_safe = rel->consider_parallel;
1058  pathnode->path.parallel_workers = parallel_degree;
1059  pathnode->path.pathkeys = NIL; /* always unordered */
1060 
1061  pathnode->bitmapqual = bitmapqual;
1062 
1063  cost_bitmap_heap_scan(&pathnode->path, root, rel,
1064  pathnode->path.param_info,
1065  bitmapqual, loop_count);
1066 
1067  return pathnode;
1068 }
1069 
1070 /*
1071  * create_bitmap_and_path
1072  * Creates a path node representing a BitmapAnd.
1073  */
1074 BitmapAndPath *
1076  RelOptInfo *rel,
1077  List *bitmapquals)
1078 {
1079  BitmapAndPath *pathnode = makeNode(BitmapAndPath);
1080  Relids required_outer = NULL;
1081  ListCell *lc;
1082 
1083  pathnode->path.pathtype = T_BitmapAnd;
1084  pathnode->path.parent = rel;
1085  pathnode->path.pathtarget = rel->reltarget;
1086 
1087  /*
1088  * Identify the required outer rels as the union of what the child paths
1089  * depend on. (Alternatively, we could insist that the caller pass this
1090  * in, but it's more convenient and reliable to compute it here.)
1091  */
1092  foreach(lc, bitmapquals)
1093  {
1094  Path *bitmapqual = (Path *) lfirst(lc);
1095 
1096  required_outer = bms_add_members(required_outer,
1097  PATH_REQ_OUTER(bitmapqual));
1098  }
1099  pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1100  required_outer);
1101 
1102  /*
1103  * Currently, a BitmapHeapPath, BitmapAndPath, or BitmapOrPath will be
1104  * parallel-safe if and only if rel->consider_parallel is set. So, we can
1105  * set the flag for this path based only on the relation-level flag,
1106  * without actually iterating over the list of children.
1107  */
1108  pathnode->path.parallel_aware = false;
1109  pathnode->path.parallel_safe = rel->consider_parallel;
1110  pathnode->path.parallel_workers = 0;
1111 
1112  pathnode->path.pathkeys = NIL; /* always unordered */
1113 
1114  pathnode->bitmapquals = bitmapquals;
1115 
1116  /* this sets bitmapselectivity as well as the regular cost fields: */
1117  cost_bitmap_and_node(pathnode, root);
1118 
1119  return pathnode;
1120 }
1121 
1122 /*
1123  * create_bitmap_or_path
1124  * Creates a path node representing a BitmapOr.
1125  */
1126 BitmapOrPath *
1128  RelOptInfo *rel,
1129  List *bitmapquals)
1130 {
1131  BitmapOrPath *pathnode = makeNode(BitmapOrPath);
1132  Relids required_outer = NULL;
1133  ListCell *lc;
1134 
1135  pathnode->path.pathtype = T_BitmapOr;
1136  pathnode->path.parent = rel;
1137  pathnode->path.pathtarget = rel->reltarget;
1138 
1139  /*
1140  * Identify the required outer rels as the union of what the child paths
1141  * depend on. (Alternatively, we could insist that the caller pass this
1142  * in, but it's more convenient and reliable to compute it here.)
1143  */
1144  foreach(lc, bitmapquals)
1145  {
1146  Path *bitmapqual = (Path *) lfirst(lc);
1147 
1148  required_outer = bms_add_members(required_outer,
1149  PATH_REQ_OUTER(bitmapqual));
1150  }
1151  pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1152  required_outer);
1153 
1154  /*
1155  * Currently, a BitmapHeapPath, BitmapAndPath, or BitmapOrPath will be
1156  * parallel-safe if and only if rel->consider_parallel is set. So, we can
1157  * set the flag for this path based only on the relation-level flag,
1158  * without actually iterating over the list of children.
1159  */
1160  pathnode->path.parallel_aware = false;
1161  pathnode->path.parallel_safe = rel->consider_parallel;
1162  pathnode->path.parallel_workers = 0;
1163 
1164  pathnode->path.pathkeys = NIL; /* always unordered */
1165 
1166  pathnode->bitmapquals = bitmapquals;
1167 
1168  /* this sets bitmapselectivity as well as the regular cost fields: */
1169  cost_bitmap_or_node(pathnode, root);
1170 
1171  return pathnode;
1172 }
1173 
1174 /*
1175  * create_tidscan_path
1176  * Creates a path corresponding to a scan by TID, returning the pathnode.
1177  */
1178 TidPath *
1180  Relids required_outer)
1181 {
1182  TidPath *pathnode = makeNode(TidPath);
1183 
1184  pathnode->path.pathtype = T_TidScan;
1185  pathnode->path.parent = rel;
1186  pathnode->path.pathtarget = rel->reltarget;
1187  pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1188  required_outer);
1189  pathnode->path.parallel_aware = false;
1190  pathnode->path.parallel_safe = rel->consider_parallel;
1191  pathnode->path.parallel_workers = 0;
1192  pathnode->path.pathkeys = NIL; /* always unordered */
1193 
1194  pathnode->tidquals = tidquals;
1195 
1196  cost_tidscan(&pathnode->path, root, rel, tidquals,
1197  pathnode->path.param_info);
1198 
1199  return pathnode;
1200 }
1201 
1202 /*
1203  * create_tidrangescan_path
1204  * Creates a path corresponding to a scan by a range of TIDs, returning
1205  * the pathnode.
1206  */
1207 TidRangePath *
1209  List *tidrangequals, Relids required_outer)
1210 {
1211  TidRangePath *pathnode = makeNode(TidRangePath);
1212 
1213  pathnode->path.pathtype = T_TidRangeScan;
1214  pathnode->path.parent = rel;
1215  pathnode->path.pathtarget = rel->reltarget;
1216  pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1217  required_outer);
1218  pathnode->path.parallel_aware = false;
1219  pathnode->path.parallel_safe = rel->consider_parallel;
1220  pathnode->path.parallel_workers = 0;
1221  pathnode->path.pathkeys = NIL; /* always unordered */
1222 
1223  pathnode->tidrangequals = tidrangequals;
1224 
1225  cost_tidrangescan(&pathnode->path, root, rel, tidrangequals,
1226  pathnode->path.param_info);
1227 
1228  return pathnode;
1229 }
1230 
1231 /*
1232  * create_append_path
1233  * Creates a path corresponding to an Append plan, returning the
1234  * pathnode.
1235  *
1236  * Note that we must handle subpaths = NIL, representing a dummy access path.
1237  * Also, there are callers that pass root = NULL.
1238  *
1239  * 'rows', when passed as a non-negative number, will be used to overwrite the
1240  * returned path's row estimate. Otherwise, the row estimate is calculated
1241  * by totalling the row estimates from the 'subpaths' list.
1242  */
1243 AppendPath *
1245  RelOptInfo *rel,
1246  List *subpaths, List *partial_subpaths,
1247  List *pathkeys, Relids required_outer,
1248  int parallel_workers, bool parallel_aware,
1249  double rows)
1250 {
1251  AppendPath *pathnode = makeNode(AppendPath);
1252  ListCell *l;
1253 
1254  Assert(!parallel_aware || parallel_workers > 0);
1255 
1256  pathnode->path.pathtype = T_Append;
1257  pathnode->path.parent = rel;
1258  pathnode->path.pathtarget = rel->reltarget;
1259 
1260  /*
1261  * If this is for a baserel (not a join or non-leaf partition), we prefer
1262  * to apply get_baserel_parampathinfo to construct a full ParamPathInfo
1263  * for the path. This supports building a Memoize path atop this path,
1264  * and if this is a partitioned table the info may be useful for run-time
1265  * pruning (cf make_partition_pruneinfo()).
1266  *
1267  * However, if we don't have "root" then that won't work and we fall back
1268  * on the simpler get_appendrel_parampathinfo. There's no point in doing
1269  * the more expensive thing for a dummy path, either.
1270  */
1271  if (rel->reloptkind == RELOPT_BASEREL && root && subpaths != NIL)
1272  pathnode->path.param_info = get_baserel_parampathinfo(root,
1273  rel,
1274  required_outer);
1275  else
1276  pathnode->path.param_info = get_appendrel_parampathinfo(rel,
1277  required_outer);
1278 
1279  pathnode->path.parallel_aware = parallel_aware;
1280  pathnode->path.parallel_safe = rel->consider_parallel;
1281  pathnode->path.parallel_workers = parallel_workers;
1282  pathnode->path.pathkeys = pathkeys;
1283 
1284  /*
1285  * For parallel append, non-partial paths are sorted by descending total
1286  * costs. That way, the total time to finish all non-partial paths is
1287  * minimized. Also, the partial paths are sorted by descending startup
1288  * costs. There may be some paths that require to do startup work by a
1289  * single worker. In such case, it's better for workers to choose the
1290  * expensive ones first, whereas the leader should choose the cheapest
1291  * startup plan.
1292  */
1293  if (pathnode->path.parallel_aware)
1294  {
1295  /*
1296  * We mustn't fiddle with the order of subpaths when the Append has
1297  * pathkeys. The order they're listed in is critical to keeping the
1298  * pathkeys valid.
1299  */
1300  Assert(pathkeys == NIL);
1301 
1303  list_sort(partial_subpaths, append_startup_cost_compare);
1304  }
1305  pathnode->first_partial_path = list_length(subpaths);
1306  pathnode->subpaths = list_concat(subpaths, partial_subpaths);
1307 
1308  /*
1309  * Apply query-wide LIMIT if known and path is for sole base relation.
1310  * (Handling this at this low level is a bit klugy.)
1311  */
1312  if (root != NULL && bms_equal(rel->relids, root->all_query_rels))
1313  pathnode->limit_tuples = root->limit_tuples;
1314  else
1315  pathnode->limit_tuples = -1.0;
1316 
1317  foreach(l, pathnode->subpaths)
1318  {
1319  Path *subpath = (Path *) lfirst(l);
1320 
1321  pathnode->path.parallel_safe = pathnode->path.parallel_safe &&
1322  subpath->parallel_safe;
1323 
1324  /* All child paths must have same parameterization */
1325  Assert(bms_equal(PATH_REQ_OUTER(subpath), required_outer));
1326  }
1327 
1328  Assert(!parallel_aware || pathnode->path.parallel_safe);
1329 
1330  /*
1331  * If there's exactly one child path then the output of the Append is
1332  * necessarily ordered the same as the child's, so we can inherit the
1333  * child's pathkeys if any, overriding whatever the caller might've said.
1334  * Furthermore, if the child's parallel awareness matches the Append's,
1335  * then the Append is a no-op and will be discarded later (in setrefs.c).
1336  * Then we can inherit the child's size and cost too, effectively charging
1337  * zero for the Append. Otherwise, we must do the normal costsize
1338  * calculation.
1339  */
1340  if (list_length(pathnode->subpaths) == 1)
1341  {
1342  Path *child = (Path *) linitial(pathnode->subpaths);
1343 
1344  if (child->parallel_aware == parallel_aware)
1345  {
1346  pathnode->path.rows = child->rows;
1347  pathnode->path.startup_cost = child->startup_cost;
1348  pathnode->path.total_cost = child->total_cost;
1349  }
1350  else
1351  cost_append(pathnode);
1352  /* Must do this last, else cost_append complains */
1353  pathnode->path.pathkeys = child->pathkeys;
1354  }
1355  else
1356  cost_append(pathnode);
1357 
1358  /* If the caller provided a row estimate, override the computed value. */
1359  if (rows >= 0)
1360  pathnode->path.rows = rows;
1361 
1362  return pathnode;
1363 }
1364 
1365 /*
1366  * append_total_cost_compare
1367  * list_sort comparator for sorting append child paths
1368  * by total_cost descending
1369  *
1370  * For equal total costs, we fall back to comparing startup costs; if those
1371  * are equal too, break ties using bms_compare on the paths' relids.
1372  * (This is to avoid getting unpredictable results from list_sort.)
1373  */
1374 static int
1376 {
1377  Path *path1 = (Path *) lfirst(a);
1378  Path *path2 = (Path *) lfirst(b);
1379  int cmp;
1380 
1381  cmp = compare_path_costs(path1, path2, TOTAL_COST);
1382  if (cmp != 0)
1383  return -cmp;
1384  return bms_compare(path1->parent->relids, path2->parent->relids);
1385 }
1386 
1387 /*
1388  * append_startup_cost_compare
1389  * list_sort comparator for sorting append child paths
1390  * by startup_cost descending
1391  *
1392  * For equal startup costs, we fall back to comparing total costs; if those
1393  * are equal too, break ties using bms_compare on the paths' relids.
1394  * (This is to avoid getting unpredictable results from list_sort.)
1395  */
1396 static int
1398 {
1399  Path *path1 = (Path *) lfirst(a);
1400  Path *path2 = (Path *) lfirst(b);
1401  int cmp;
1402 
1403  cmp = compare_path_costs(path1, path2, STARTUP_COST);
1404  if (cmp != 0)
1405  return -cmp;
1406  return bms_compare(path1->parent->relids, path2->parent->relids);
1407 }
1408 
1409 /*
1410  * create_merge_append_path
1411  * Creates a path corresponding to a MergeAppend plan, returning the
1412  * pathnode.
1413  */
1416  RelOptInfo *rel,
1417  List *subpaths,
1418  List *pathkeys,
1419  Relids required_outer)
1420 {
1422  Cost input_startup_cost;
1423  Cost input_total_cost;
1424  ListCell *l;
1425 
1426  pathnode->path.pathtype = T_MergeAppend;
1427  pathnode->path.parent = rel;
1428  pathnode->path.pathtarget = rel->reltarget;
1429  pathnode->path.param_info = get_appendrel_parampathinfo(rel,
1430  required_outer);
1431  pathnode->path.parallel_aware = false;
1432  pathnode->path.parallel_safe = rel->consider_parallel;
1433  pathnode->path.parallel_workers = 0;
1434  pathnode->path.pathkeys = pathkeys;
1435  pathnode->subpaths = subpaths;
1436 
1437  /*
1438  * Apply query-wide LIMIT if known and path is for sole base relation.
1439  * (Handling this at this low level is a bit klugy.)
1440  */
1441  if (bms_equal(rel->relids, root->all_query_rels))
1442  pathnode->limit_tuples = root->limit_tuples;
1443  else
1444  pathnode->limit_tuples = -1.0;
1445 
1446  /*
1447  * Add up the sizes and costs of the input paths.
1448  */
1449  pathnode->path.rows = 0;
1450  input_startup_cost = 0;
1451  input_total_cost = 0;
1452  foreach(l, subpaths)
1453  {
1454  Path *subpath = (Path *) lfirst(l);
1455 
1456  pathnode->path.rows += subpath->rows;
1457  pathnode->path.parallel_safe = pathnode->path.parallel_safe &&
1458  subpath->parallel_safe;
1459 
1460  if (pathkeys_contained_in(pathkeys, subpath->pathkeys))
1461  {
1462  /* Subpath is adequately ordered, we won't need to sort it */
1463  input_startup_cost += subpath->startup_cost;
1464  input_total_cost += subpath->total_cost;
1465  }
1466  else
1467  {
1468  /* We'll need to insert a Sort node, so include cost for that */
1469  Path sort_path; /* dummy for result of cost_sort */
1470 
1471  cost_sort(&sort_path,
1472  root,
1473  pathkeys,
1474  subpath->total_cost,
1475  subpath->rows,
1476  subpath->pathtarget->width,
1477  0.0,
1478  work_mem,
1479  pathnode->limit_tuples);
1480  input_startup_cost += sort_path.startup_cost;
1481  input_total_cost += sort_path.total_cost;
1482  }
1483 
1484  /* All child paths must have same parameterization */
1485  Assert(bms_equal(PATH_REQ_OUTER(subpath), required_outer));
1486  }
1487 
1488  /*
1489  * Now we can compute total costs of the MergeAppend. If there's exactly
1490  * one child path and its parallel awareness matches that of the
1491  * MergeAppend, then the MergeAppend is a no-op and will be discarded
1492  * later (in setrefs.c); otherwise we do the normal cost calculation.
1493  */
1494  if (list_length(subpaths) == 1 &&
1495  ((Path *) linitial(subpaths))->parallel_aware ==
1496  pathnode->path.parallel_aware)
1497  {
1498  pathnode->path.startup_cost = input_startup_cost;
1499  pathnode->path.total_cost = input_total_cost;
1500  }
1501  else
1502  cost_merge_append(&pathnode->path, root,
1503  pathkeys, list_length(subpaths),
1504  input_startup_cost, input_total_cost,
1505  pathnode->path.rows);
1506 
1507  return pathnode;
1508 }
1509 
1510 /*
1511  * create_group_result_path
1512  * Creates a path representing a Result-and-nothing-else plan.
1513  *
1514  * This is only used for degenerate grouping cases, in which we know we
1515  * need to produce one result row, possibly filtered by a HAVING qual.
1516  */
1519  PathTarget *target, List *havingqual)
1520 {
1522 
1523  pathnode->path.pathtype = T_Result;
1524  pathnode->path.parent = rel;
1525  pathnode->path.pathtarget = target;
1526  pathnode->path.param_info = NULL; /* there are no other rels... */
1527  pathnode->path.parallel_aware = false;
1528  pathnode->path.parallel_safe = rel->consider_parallel;
1529  pathnode->path.parallel_workers = 0;
1530  pathnode->path.pathkeys = NIL;
1531  pathnode->quals = havingqual;
1532 
1533  /*
1534  * We can't quite use cost_resultscan() because the quals we want to
1535  * account for are not baserestrict quals of the rel. Might as well just
1536  * hack it here.
1537  */
1538  pathnode->path.rows = 1;
1539  pathnode->path.startup_cost = target->cost.startup;
1540  pathnode->path.total_cost = target->cost.startup +
1541  cpu_tuple_cost + target->cost.per_tuple;
1542 
1543  /*
1544  * Add cost of qual, if any --- but we ignore its selectivity, since our
1545  * rowcount estimate should be 1 no matter what the qual is.
1546  */
1547  if (havingqual)
1548  {
1549  QualCost qual_cost;
1550 
1551  cost_qual_eval(&qual_cost, havingqual, root);
1552  /* havingqual is evaluated once at startup */
1553  pathnode->path.startup_cost += qual_cost.startup + qual_cost.per_tuple;
1554  pathnode->path.total_cost += qual_cost.startup + qual_cost.per_tuple;
1555  }
1556 
1557  return pathnode;
1558 }
1559 
1560 /*
1561  * create_material_path
1562  * Creates a path corresponding to a Material plan, returning the
1563  * pathnode.
1564  */
1565 MaterialPath *
1567 {
1568  MaterialPath *pathnode = makeNode(MaterialPath);
1569 
1570  Assert(subpath->parent == rel);
1571 
1572  pathnode->path.pathtype = T_Material;
1573  pathnode->path.parent = rel;
1574  pathnode->path.pathtarget = rel->reltarget;
1575  pathnode->path.param_info = subpath->param_info;
1576  pathnode->path.parallel_aware = false;
1577  pathnode->path.parallel_safe = rel->consider_parallel &&
1578  subpath->parallel_safe;
1579  pathnode->path.parallel_workers = subpath->parallel_workers;
1580  pathnode->path.pathkeys = subpath->pathkeys;
1581 
1582  pathnode->subpath = subpath;
1583 
1584  cost_material(&pathnode->path,
1585  subpath->startup_cost,
1586  subpath->total_cost,
1587  subpath->rows,
1588  subpath->pathtarget->width);
1589 
1590  return pathnode;
1591 }
1592 
1593 /*
1594  * create_memoize_path
1595  * Creates a path corresponding to a Memoize plan, returning the pathnode.
1596  */
1597 MemoizePath *
1599  List *param_exprs, List *hash_operators,
1600  bool singlerow, bool binary_mode, double calls)
1601 {
1602  MemoizePath *pathnode = makeNode(MemoizePath);
1603 
1604  Assert(subpath->parent == rel);
1605 
1606  pathnode->path.pathtype = T_Memoize;
1607  pathnode->path.parent = rel;
1608  pathnode->path.pathtarget = rel->reltarget;
1609  pathnode->path.param_info = subpath->param_info;
1610  pathnode->path.parallel_aware = false;
1611  pathnode->path.parallel_safe = rel->consider_parallel &&
1612  subpath->parallel_safe;
1613  pathnode->path.parallel_workers = subpath->parallel_workers;
1614  pathnode->path.pathkeys = subpath->pathkeys;
1615 
1616  pathnode->subpath = subpath;
1617  pathnode->hash_operators = hash_operators;
1618  pathnode->param_exprs = param_exprs;
1619  pathnode->singlerow = singlerow;
1620  pathnode->binary_mode = binary_mode;
1621  pathnode->calls = calls;
1622 
1623  /*
1624  * For now we set est_entries to 0. cost_memoize_rescan() does all the
1625  * hard work to determine how many cache entries there are likely to be,
1626  * so it seems best to leave it up to that function to fill this field in.
1627  * If left at 0, the executor will make a guess at a good value.
1628  */
1629  pathnode->est_entries = 0;
1630 
1631  /*
1632  * Add a small additional charge for caching the first entry. All the
1633  * harder calculations for rescans are performed in cost_memoize_rescan().
1634  */
1635  pathnode->path.startup_cost = subpath->startup_cost + cpu_tuple_cost;
1636  pathnode->path.total_cost = subpath->total_cost + cpu_tuple_cost;
1637  pathnode->path.rows = subpath->rows;
1638 
1639  return pathnode;
1640 }
1641 
1642 /*
1643  * create_unique_path
1644  * Creates a path representing elimination of distinct rows from the
1645  * input data. Distinct-ness is defined according to the needs of the
1646  * semijoin represented by sjinfo. If it is not possible to identify
1647  * how to make the data unique, NULL is returned.
1648  *
1649  * If used at all, this is likely to be called repeatedly on the same rel;
1650  * and the input subpath should always be the same (the cheapest_total path
1651  * for the rel). So we cache the result.
1652  */
1653 UniquePath *
1655  SpecialJoinInfo *sjinfo)
1656 {
1657  UniquePath *pathnode;
1658  Path sort_path; /* dummy for result of cost_sort */
1659  Path agg_path; /* dummy for result of cost_agg */
1660  MemoryContext oldcontext;
1661  int numCols;
1662 
1663  /* Caller made a mistake if subpath isn't cheapest_total ... */
1665  Assert(subpath->parent == rel);
1666  /* ... or if SpecialJoinInfo is the wrong one */
1667  Assert(sjinfo->jointype == JOIN_SEMI);
1668  Assert(bms_equal(rel->relids, sjinfo->syn_righthand));
1669 
1670  /* If result already cached, return it */
1671  if (rel->cheapest_unique_path)
1672  return (UniquePath *) rel->cheapest_unique_path;
1673 
1674  /* If it's not possible to unique-ify, return NULL */
1675  if (!(sjinfo->semi_can_btree || sjinfo->semi_can_hash))
1676  return NULL;
1677 
1678  /*
1679  * When called during GEQO join planning, we are in a short-lived memory
1680  * context. We must make sure that the path and any subsidiary data
1681  * structures created for a baserel survive the GEQO cycle, else the
1682  * baserel is trashed for future GEQO cycles. On the other hand, when we
1683  * are creating those for a joinrel during GEQO, we don't want them to
1684  * clutter the main planning context. Upshot is that the best solution is
1685  * to explicitly allocate memory in the same context the given RelOptInfo
1686  * is in.
1687  */
1688  oldcontext = MemoryContextSwitchTo(GetMemoryChunkContext(rel));
1689 
1690  pathnode = makeNode(UniquePath);
1691 
1692  pathnode->path.pathtype = T_Unique;
1693  pathnode->path.parent = rel;
1694  pathnode->path.pathtarget = rel->reltarget;
1695  pathnode->path.param_info = subpath->param_info;
1696  pathnode->path.parallel_aware = false;
1697  pathnode->path.parallel_safe = rel->consider_parallel &&
1698  subpath->parallel_safe;
1699  pathnode->path.parallel_workers = subpath->parallel_workers;
1700 
1701  /*
1702  * Assume the output is unsorted, since we don't necessarily have pathkeys
1703  * to represent it. (This might get overridden below.)
1704  */
1705  pathnode->path.pathkeys = NIL;
1706 
1707  pathnode->subpath = subpath;
1708 
1709  /*
1710  * Under GEQO and when planning child joins, the sjinfo might be
1711  * short-lived, so we'd better make copies of data structures we extract
1712  * from it.
1713  */
1714  pathnode->in_operators = copyObject(sjinfo->semi_operators);
1715  pathnode->uniq_exprs = copyObject(sjinfo->semi_rhs_exprs);
1716 
1717  /*
1718  * If the input is a relation and it has a unique index that proves the
1719  * semi_rhs_exprs are unique, then we don't need to do anything. Note
1720  * that relation_has_unique_index_for automatically considers restriction
1721  * clauses for the rel, as well.
1722  */
1723  if (rel->rtekind == RTE_RELATION && sjinfo->semi_can_btree &&
1725  sjinfo->semi_rhs_exprs,
1726  sjinfo->semi_operators))
1727  {
1728  pathnode->umethod = UNIQUE_PATH_NOOP;
1729  pathnode->path.rows = rel->rows;
1730  pathnode->path.startup_cost = subpath->startup_cost;
1731  pathnode->path.total_cost = subpath->total_cost;
1732  pathnode->path.pathkeys = subpath->pathkeys;
1733 
1734  rel->cheapest_unique_path = (Path *) pathnode;
1735 
1736  MemoryContextSwitchTo(oldcontext);
1737 
1738  return pathnode;
1739  }
1740 
1741  /*
1742  * If the input is a subquery whose output must be unique already, then we
1743  * don't need to do anything. The test for uniqueness has to consider
1744  * exactly which columns we are extracting; for example "SELECT DISTINCT
1745  * x,y" doesn't guarantee that x alone is distinct. So we cannot check for
1746  * this optimization unless semi_rhs_exprs consists only of simple Vars
1747  * referencing subquery outputs. (Possibly we could do something with
1748  * expressions in the subquery outputs, too, but for now keep it simple.)
1749  */
1750  if (rel->rtekind == RTE_SUBQUERY)
1751  {
1752  RangeTblEntry *rte = planner_rt_fetch(rel->relid, root);
1753 
1755  {
1756  List *sub_tlist_colnos;
1757 
1758  sub_tlist_colnos = translate_sub_tlist(sjinfo->semi_rhs_exprs,
1759  rel->relid);
1760 
1761  if (sub_tlist_colnos &&
1763  sub_tlist_colnos,
1764  sjinfo->semi_operators))
1765  {
1766  pathnode->umethod = UNIQUE_PATH_NOOP;
1767  pathnode->path.rows = rel->rows;
1768  pathnode->path.startup_cost = subpath->startup_cost;
1769  pathnode->path.total_cost = subpath->total_cost;
1770  pathnode->path.pathkeys = subpath->pathkeys;
1771 
1772  rel->cheapest_unique_path = (Path *) pathnode;
1773 
1774  MemoryContextSwitchTo(oldcontext);
1775 
1776  return pathnode;
1777  }
1778  }
1779  }
1780 
1781  /* Estimate number of output rows */
1782  pathnode->path.rows = estimate_num_groups(root,
1783  sjinfo->semi_rhs_exprs,
1784  rel->rows,
1785  NULL,
1786  NULL);
1787  numCols = list_length(sjinfo->semi_rhs_exprs);
1788 
1789  if (sjinfo->semi_can_btree)
1790  {
1791  /*
1792  * Estimate cost for sort+unique implementation
1793  */
1794  cost_sort(&sort_path, root, NIL,
1795  subpath->total_cost,
1796  rel->rows,
1797  subpath->pathtarget->width,
1798  0.0,
1799  work_mem,
1800  -1.0);
1801 
1802  /*
1803  * Charge one cpu_operator_cost per comparison per input tuple. We
1804  * assume all columns get compared at most of the tuples. (XXX
1805  * probably this is an overestimate.) This should agree with
1806  * create_upper_unique_path.
1807  */
1808  sort_path.total_cost += cpu_operator_cost * rel->rows * numCols;
1809  }
1810 
1811  if (sjinfo->semi_can_hash)
1812  {
1813  /*
1814  * Estimate the overhead per hashtable entry at 64 bytes (same as in
1815  * planner.c).
1816  */
1817  int hashentrysize = subpath->pathtarget->width + 64;
1818 
1819  if (hashentrysize * pathnode->path.rows > get_hash_memory_limit())
1820  {
1821  /*
1822  * We should not try to hash. Hack the SpecialJoinInfo to
1823  * remember this, in case we come through here again.
1824  */
1825  sjinfo->semi_can_hash = false;
1826  }
1827  else
1828  cost_agg(&agg_path, root,
1829  AGG_HASHED, NULL,
1830  numCols, pathnode->path.rows,
1831  NIL,
1832  subpath->startup_cost,
1833  subpath->total_cost,
1834  rel->rows,
1835  subpath->pathtarget->width);
1836  }
1837 
1838  if (sjinfo->semi_can_btree && sjinfo->semi_can_hash)
1839  {
1840  if (agg_path.total_cost < sort_path.total_cost)
1841  pathnode->umethod = UNIQUE_PATH_HASH;
1842  else
1843  pathnode->umethod = UNIQUE_PATH_SORT;
1844  }
1845  else if (sjinfo->semi_can_btree)
1846  pathnode->umethod = UNIQUE_PATH_SORT;
1847  else if (sjinfo->semi_can_hash)
1848  pathnode->umethod = UNIQUE_PATH_HASH;
1849  else
1850  {
1851  /* we can get here only if we abandoned hashing above */
1852  MemoryContextSwitchTo(oldcontext);
1853  return NULL;
1854  }
1855 
1856  if (pathnode->umethod == UNIQUE_PATH_HASH)
1857  {
1858  pathnode->path.startup_cost = agg_path.startup_cost;
1859  pathnode->path.total_cost = agg_path.total_cost;
1860  }
1861  else
1862  {
1863  pathnode->path.startup_cost = sort_path.startup_cost;
1864  pathnode->path.total_cost = sort_path.total_cost;
1865  }
1866 
1867  rel->cheapest_unique_path = (Path *) pathnode;
1868 
1869  MemoryContextSwitchTo(oldcontext);
1870 
1871  return pathnode;
1872 }
1873 
1874 /*
1875  * create_gather_merge_path
1876  *
1877  * Creates a path corresponding to a gather merge scan, returning
1878  * the pathnode.
1879  */
1882  PathTarget *target, List *pathkeys,
1883  Relids required_outer, double *rows)
1884 {
1886  Cost input_startup_cost = 0;
1887  Cost input_total_cost = 0;
1888 
1889  Assert(subpath->parallel_safe);
1890  Assert(pathkeys);
1891 
1892  pathnode->path.pathtype = T_GatherMerge;
1893  pathnode->path.parent = rel;
1894  pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1895  required_outer);
1896  pathnode->path.parallel_aware = false;
1897 
1898  pathnode->subpath = subpath;
1899  pathnode->num_workers = subpath->parallel_workers;
1900  pathnode->path.pathkeys = pathkeys;
1901  pathnode->path.pathtarget = target ? target : rel->reltarget;
1902  pathnode->path.rows += subpath->rows;
1903 
1904  if (pathkeys_contained_in(pathkeys, subpath->pathkeys))
1905  {
1906  /* Subpath is adequately ordered, we won't need to sort it */
1907  input_startup_cost += subpath->startup_cost;
1908  input_total_cost += subpath->total_cost;
1909  }
1910  else
1911  {
1912  /* We'll need to insert a Sort node, so include cost for that */
1913  Path sort_path; /* dummy for result of cost_sort */
1914 
1915  cost_sort(&sort_path,
1916  root,
1917  pathkeys,
1918  subpath->total_cost,
1919  subpath->rows,
1920  subpath->pathtarget->width,
1921  0.0,
1922  work_mem,
1923  -1);
1924  input_startup_cost += sort_path.startup_cost;
1925  input_total_cost += sort_path.total_cost;
1926  }
1927 
1928  cost_gather_merge(pathnode, root, rel, pathnode->path.param_info,
1929  input_startup_cost, input_total_cost, rows);
1930 
1931  return pathnode;
1932 }
1933 
1934 /*
1935  * translate_sub_tlist - get subquery column numbers represented by tlist
1936  *
1937  * The given targetlist usually contains only Vars referencing the given relid.
1938  * Extract their varattnos (ie, the column numbers of the subquery) and return
1939  * as an integer List.
1940  *
1941  * If any of the tlist items is not a simple Var, we cannot determine whether
1942  * the subquery's uniqueness condition (if any) matches ours, so punt and
1943  * return NIL.
1944  */
1945 static List *
1946 translate_sub_tlist(List *tlist, int relid)
1947 {
1948  List *result = NIL;
1949  ListCell *l;
1950 
1951  foreach(l, tlist)
1952  {
1953  Var *var = (Var *) lfirst(l);
1954 
1955  if (!var || !IsA(var, Var) ||
1956  var->varno != relid)
1957  return NIL; /* punt */
1958 
1959  result = lappend_int(result, var->varattno);
1960  }
1961  return result;
1962 }
1963 
1964 /*
1965  * create_gather_path
1966  * Creates a path corresponding to a gather scan, returning the
1967  * pathnode.
1968  *
1969  * 'rows' may optionally be set to override row estimates from other sources.
1970  */
1971 GatherPath *
1973  PathTarget *target, Relids required_outer, double *rows)
1974 {
1975  GatherPath *pathnode = makeNode(GatherPath);
1976 
1977  Assert(subpath->parallel_safe);
1978 
1979  pathnode->path.pathtype = T_Gather;
1980  pathnode->path.parent = rel;
1981  pathnode->path.pathtarget = target;
1982  pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
1983  required_outer);
1984  pathnode->path.parallel_aware = false;
1985  pathnode->path.parallel_safe = false;
1986  pathnode->path.parallel_workers = 0;
1987  pathnode->path.pathkeys = NIL; /* Gather has unordered result */
1988 
1989  pathnode->subpath = subpath;
1990  pathnode->num_workers = subpath->parallel_workers;
1991  pathnode->single_copy = false;
1992 
1993  if (pathnode->num_workers == 0)
1994  {
1995  pathnode->path.pathkeys = subpath->pathkeys;
1996  pathnode->num_workers = 1;
1997  pathnode->single_copy = true;
1998  }
1999 
2000  cost_gather(pathnode, root, rel, pathnode->path.param_info, rows);
2001 
2002  return pathnode;
2003 }
2004 
2005 /*
2006  * create_subqueryscan_path
2007  * Creates a path corresponding to a scan of a subquery,
2008  * returning the pathnode.
2009  *
2010  * Caller must pass trivial_pathtarget = true if it believes rel->reltarget to
2011  * be trivial, ie just a fetch of all the subquery output columns in order.
2012  * While we could determine that here, the caller can usually do it more
2013  * efficiently (or at least amortize it over multiple calls).
2014  */
2017  bool trivial_pathtarget,
2018  List *pathkeys, Relids required_outer)
2019 {
2021 
2022  pathnode->path.pathtype = T_SubqueryScan;
2023  pathnode->path.parent = rel;
2024  pathnode->path.pathtarget = rel->reltarget;
2025  pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
2026  required_outer);
2027  pathnode->path.parallel_aware = false;
2028  pathnode->path.parallel_safe = rel->consider_parallel &&
2029  subpath->parallel_safe;
2030  pathnode->path.parallel_workers = subpath->parallel_workers;
2031  pathnode->path.pathkeys = pathkeys;
2032  pathnode->subpath = subpath;
2033 
2034  cost_subqueryscan(pathnode, root, rel, pathnode->path.param_info,
2035  trivial_pathtarget);
2036 
2037  return pathnode;
2038 }
2039 
2040 /*
2041  * create_functionscan_path
2042  * Creates a path corresponding to a sequential scan of a function,
2043  * returning the pathnode.
2044  */
2045 Path *
2047  List *pathkeys, Relids required_outer)
2048 {
2049  Path *pathnode = makeNode(Path);
2050 
2051  pathnode->pathtype = T_FunctionScan;
2052  pathnode->parent = rel;
2053  pathnode->pathtarget = rel->reltarget;
2054  pathnode->param_info = get_baserel_parampathinfo(root, rel,
2055  required_outer);
2056  pathnode->parallel_aware = false;
2057  pathnode->parallel_safe = rel->consider_parallel;
2058  pathnode->parallel_workers = 0;
2059  pathnode->pathkeys = pathkeys;
2060 
2061  cost_functionscan(pathnode, root, rel, pathnode->param_info);
2062 
2063  return pathnode;
2064 }
2065 
2066 /*
2067  * create_tablefuncscan_path
2068  * Creates a path corresponding to a sequential scan of a table function,
2069  * returning the pathnode.
2070  */
2071 Path *
2073  Relids required_outer)
2074 {
2075  Path *pathnode = makeNode(Path);
2076 
2077  pathnode->pathtype = T_TableFuncScan;
2078  pathnode->parent = rel;
2079  pathnode->pathtarget = rel->reltarget;
2080  pathnode->param_info = get_baserel_parampathinfo(root, rel,
2081  required_outer);
2082  pathnode->parallel_aware = false;
2083  pathnode->parallel_safe = rel->consider_parallel;
2084  pathnode->parallel_workers = 0;
2085  pathnode->pathkeys = NIL; /* result is always unordered */
2086 
2087  cost_tablefuncscan(pathnode, root, rel, pathnode->param_info);
2088 
2089  return pathnode;
2090 }
2091 
2092 /*
2093  * create_valuesscan_path
2094  * Creates a path corresponding to a scan of a VALUES list,
2095  * returning the pathnode.
2096  */
2097 Path *
2099  Relids required_outer)
2100 {
2101  Path *pathnode = makeNode(Path);
2102 
2103  pathnode->pathtype = T_ValuesScan;
2104  pathnode->parent = rel;
2105  pathnode->pathtarget = rel->reltarget;
2106  pathnode->param_info = get_baserel_parampathinfo(root, rel,
2107  required_outer);
2108  pathnode->parallel_aware = false;
2109  pathnode->parallel_safe = rel->consider_parallel;
2110  pathnode->parallel_workers = 0;
2111  pathnode->pathkeys = NIL; /* result is always unordered */
2112 
2113  cost_valuesscan(pathnode, root, rel, pathnode->param_info);
2114 
2115  return pathnode;
2116 }
2117 
2118 /*
2119  * create_ctescan_path
2120  * Creates a path corresponding to a scan of a non-self-reference CTE,
2121  * returning the pathnode.
2122  */
2123 Path *
2125  List *pathkeys, Relids required_outer)
2126 {
2127  Path *pathnode = makeNode(Path);
2128 
2129  pathnode->pathtype = T_CteScan;
2130  pathnode->parent = rel;
2131  pathnode->pathtarget = rel->reltarget;
2132  pathnode->param_info = get_baserel_parampathinfo(root, rel,
2133  required_outer);
2134  pathnode->parallel_aware = false;
2135  pathnode->parallel_safe = rel->consider_parallel;
2136  pathnode->parallel_workers = 0;
2137  pathnode->pathkeys = pathkeys;
2138 
2139  cost_ctescan(pathnode, root, rel, pathnode->param_info);
2140 
2141  return pathnode;
2142 }
2143 
2144 /*
2145  * create_namedtuplestorescan_path
2146  * Creates a path corresponding to a scan of a named tuplestore, returning
2147  * the pathnode.
2148  */
2149 Path *
2151  Relids required_outer)
2152 {
2153  Path *pathnode = makeNode(Path);
2154 
2155  pathnode->pathtype = T_NamedTuplestoreScan;
2156  pathnode->parent = rel;
2157  pathnode->pathtarget = rel->reltarget;
2158  pathnode->param_info = get_baserel_parampathinfo(root, rel,
2159  required_outer);
2160  pathnode->parallel_aware = false;
2161  pathnode->parallel_safe = rel->consider_parallel;
2162  pathnode->parallel_workers = 0;
2163  pathnode->pathkeys = NIL; /* result is always unordered */
2164 
2165  cost_namedtuplestorescan(pathnode, root, rel, pathnode->param_info);
2166 
2167  return pathnode;
2168 }
2169 
2170 /*
2171  * create_resultscan_path
2172  * Creates a path corresponding to a scan of an RTE_RESULT relation,
2173  * returning the pathnode.
2174  */
2175 Path *
2177  Relids required_outer)
2178 {
2179  Path *pathnode = makeNode(Path);
2180 
2181  pathnode->pathtype = T_Result;
2182  pathnode->parent = rel;
2183  pathnode->pathtarget = rel->reltarget;
2184  pathnode->param_info = get_baserel_parampathinfo(root, rel,
2185  required_outer);
2186  pathnode->parallel_aware = false;
2187  pathnode->parallel_safe = rel->consider_parallel;
2188  pathnode->parallel_workers = 0;
2189  pathnode->pathkeys = NIL; /* result is always unordered */
2190 
2191  cost_resultscan(pathnode, root, rel, pathnode->param_info);
2192 
2193  return pathnode;
2194 }
2195 
2196 /*
2197  * create_worktablescan_path
2198  * Creates a path corresponding to a scan of a self-reference CTE,
2199  * returning the pathnode.
2200  */
2201 Path *
2203  Relids required_outer)
2204 {
2205  Path *pathnode = makeNode(Path);
2206 
2207  pathnode->pathtype = T_WorkTableScan;
2208  pathnode->parent = rel;
2209  pathnode->pathtarget = rel->reltarget;
2210  pathnode->param_info = get_baserel_parampathinfo(root, rel,
2211  required_outer);
2212  pathnode->parallel_aware = false;
2213  pathnode->parallel_safe = rel->consider_parallel;
2214  pathnode->parallel_workers = 0;
2215  pathnode->pathkeys = NIL; /* result is always unordered */
2216 
2217  /* Cost is the same as for a regular CTE scan */
2218  cost_ctescan(pathnode, root, rel, pathnode->param_info);
2219 
2220  return pathnode;
2221 }
2222 
2223 /*
2224  * create_foreignscan_path
2225  * Creates a path corresponding to a scan of a foreign base table,
2226  * returning the pathnode.
2227  *
2228  * This function is never called from core Postgres; rather, it's expected
2229  * to be called by the GetForeignPaths function of a foreign data wrapper.
2230  * We make the FDW supply all fields of the path, since we do not have any way
2231  * to calculate them in core. However, there is a usually-sane default for
2232  * the pathtarget (rel->reltarget), so we let a NULL for "target" select that.
2233  */
2234 ForeignPath *
2236  PathTarget *target,
2237  double rows, Cost startup_cost, Cost total_cost,
2238  List *pathkeys,
2239  Relids required_outer,
2240  Path *fdw_outerpath,
2241  List *fdw_restrictinfo,
2242  List *fdw_private)
2243 {
2244  ForeignPath *pathnode = makeNode(ForeignPath);
2245 
2246  /* Historically some FDWs were confused about when to use this */
2247  Assert(IS_SIMPLE_REL(rel));
2248 
2249  pathnode->path.pathtype = T_ForeignScan;
2250  pathnode->path.parent = rel;
2251  pathnode->path.pathtarget = target ? target : rel->reltarget;
2252  pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
2253  required_outer);
2254  pathnode->path.parallel_aware = false;
2255  pathnode->path.parallel_safe = rel->consider_parallel;
2256  pathnode->path.parallel_workers = 0;
2257  pathnode->path.rows = rows;
2258  pathnode->path.startup_cost = startup_cost;
2259  pathnode->path.total_cost = total_cost;
2260  pathnode->path.pathkeys = pathkeys;
2261 
2262  pathnode->fdw_outerpath = fdw_outerpath;
2263  pathnode->fdw_restrictinfo = fdw_restrictinfo;
2264  pathnode->fdw_private = fdw_private;
2265 
2266  return pathnode;
2267 }
2268 
2269 /*
2270  * create_foreign_join_path
2271  * Creates a path corresponding to a scan of a foreign join,
2272  * returning the pathnode.
2273  *
2274  * This function is never called from core Postgres; rather, it's expected
2275  * to be called by the GetForeignJoinPaths function of a foreign data wrapper.
2276  * We make the FDW supply all fields of the path, since we do not have any way
2277  * to calculate them in core. However, there is a usually-sane default for
2278  * the pathtarget (rel->reltarget), so we let a NULL for "target" select that.
2279  */
2280 ForeignPath *
2282  PathTarget *target,
2283  double rows, Cost startup_cost, Cost total_cost,
2284  List *pathkeys,
2285  Relids required_outer,
2286  Path *fdw_outerpath,
2287  List *fdw_restrictinfo,
2288  List *fdw_private)
2289 {
2290  ForeignPath *pathnode = makeNode(ForeignPath);
2291 
2292  /*
2293  * We should use get_joinrel_parampathinfo to handle parameterized paths,
2294  * but the API of this function doesn't support it, and existing
2295  * extensions aren't yet trying to build such paths anyway. For the
2296  * moment just throw an error if someone tries it; eventually we should
2297  * revisit this.
2298  */
2299  if (!bms_is_empty(required_outer) || !bms_is_empty(rel->lateral_relids))
2300  elog(ERROR, "parameterized foreign joins are not supported yet");
2301 
2302  pathnode->path.pathtype = T_ForeignScan;
2303  pathnode->path.parent = rel;
2304  pathnode->path.pathtarget = target ? target : rel->reltarget;
2305  pathnode->path.param_info = NULL; /* XXX see above */
2306  pathnode->path.parallel_aware = false;
2307  pathnode->path.parallel_safe = rel->consider_parallel;
2308  pathnode->path.parallel_workers = 0;
2309  pathnode->path.rows = rows;
2310  pathnode->path.startup_cost = startup_cost;
2311  pathnode->path.total_cost = total_cost;
2312  pathnode->path.pathkeys = pathkeys;
2313 
2314  pathnode->fdw_outerpath = fdw_outerpath;
2315  pathnode->fdw_restrictinfo = fdw_restrictinfo;
2316  pathnode->fdw_private = fdw_private;
2317 
2318  return pathnode;
2319 }
2320 
2321 /*
2322  * create_foreign_upper_path
2323  * Creates a path corresponding to an upper relation that's computed
2324  * directly by an FDW, returning the pathnode.
2325  *
2326  * This function is never called from core Postgres; rather, it's expected to
2327  * be called by the GetForeignUpperPaths function of a foreign data wrapper.
2328  * We make the FDW supply all fields of the path, since we do not have any way
2329  * to calculate them in core. However, there is a usually-sane default for
2330  * the pathtarget (rel->reltarget), so we let a NULL for "target" select that.
2331  */
2332 ForeignPath *
2334  PathTarget *target,
2335  double rows, Cost startup_cost, Cost total_cost,
2336  List *pathkeys,
2337  Path *fdw_outerpath,
2338  List *fdw_restrictinfo,
2339  List *fdw_private)
2340 {
2341  ForeignPath *pathnode = makeNode(ForeignPath);
2342 
2343  /*
2344  * Upper relations should never have any lateral references, since joining
2345  * is complete.
2346  */
2348 
2349  pathnode->path.pathtype = T_ForeignScan;
2350  pathnode->path.parent = rel;
2351  pathnode->path.pathtarget = target ? target : rel->reltarget;
2352  pathnode->path.param_info = NULL;
2353  pathnode->path.parallel_aware = false;
2354  pathnode->path.parallel_safe = rel->consider_parallel;
2355  pathnode->path.parallel_workers = 0;
2356  pathnode->path.rows = rows;
2357  pathnode->path.startup_cost = startup_cost;
2358  pathnode->path.total_cost = total_cost;
2359  pathnode->path.pathkeys = pathkeys;
2360 
2361  pathnode->fdw_outerpath = fdw_outerpath;
2362  pathnode->fdw_restrictinfo = fdw_restrictinfo;
2363  pathnode->fdw_private = fdw_private;
2364 
2365  return pathnode;
2366 }
2367 
2368 /*
2369  * calc_nestloop_required_outer
2370  * Compute the required_outer set for a nestloop join path
2371  *
2372  * Note: when considering a child join, the inputs nonetheless use top-level
2373  * parent relids
2374  *
2375  * Note: result must not share storage with either input
2376  */
2377 Relids
2379  Relids outer_paramrels,
2380  Relids innerrelids,
2381  Relids inner_paramrels)
2382 {
2383  Relids required_outer;
2384 
2385  /* inner_path can require rels from outer path, but not vice versa */
2386  Assert(!bms_overlap(outer_paramrels, innerrelids));
2387  /* easy case if inner path is not parameterized */
2388  if (!inner_paramrels)
2389  return bms_copy(outer_paramrels);
2390  /* else, form the union ... */
2391  required_outer = bms_union(outer_paramrels, inner_paramrels);
2392  /* ... and remove any mention of now-satisfied outer rels */
2393  required_outer = bms_del_members(required_outer,
2394  outerrelids);
2395  return required_outer;
2396 }
2397 
2398 /*
2399  * calc_non_nestloop_required_outer
2400  * Compute the required_outer set for a merge or hash join path
2401  *
2402  * Note: result must not share storage with either input
2403  */
2404 Relids
2405 calc_non_nestloop_required_outer(Path *outer_path, Path *inner_path)
2406 {
2407  Relids outer_paramrels = PATH_REQ_OUTER(outer_path);
2408  Relids inner_paramrels = PATH_REQ_OUTER(inner_path);
2409  Relids innerrelids PG_USED_FOR_ASSERTS_ONLY;
2410  Relids outerrelids PG_USED_FOR_ASSERTS_ONLY;
2411  Relids required_outer;
2412 
2413  /*
2414  * Any parameterization of the input paths refers to topmost parents of
2415  * the relevant relations, because reparameterize_path_by_child() hasn't
2416  * been called yet. So we must consider topmost parents of the relations
2417  * being joined, too, while checking for disallowed parameterization
2418  * cases.
2419  */
2420  if (inner_path->parent->top_parent_relids)
2421  innerrelids = inner_path->parent->top_parent_relids;
2422  else
2423  innerrelids = inner_path->parent->relids;
2424 
2425  if (outer_path->parent->top_parent_relids)
2426  outerrelids = outer_path->parent->top_parent_relids;
2427  else
2428  outerrelids = outer_path->parent->relids;
2429 
2430  /* neither path can require rels from the other */
2431  Assert(!bms_overlap(outer_paramrels, innerrelids));
2432  Assert(!bms_overlap(inner_paramrels, outerrelids));
2433  /* form the union ... */
2434  required_outer = bms_union(outer_paramrels, inner_paramrels);
2435  /* we do not need an explicit test for empty; bms_union gets it right */
2436  return required_outer;
2437 }
2438 
2439 /*
2440  * create_nestloop_path
2441  * Creates a pathnode corresponding to a nestloop join between two
2442  * relations.
2443  *
2444  * 'joinrel' is the join relation.
2445  * 'jointype' is the type of join required
2446  * 'workspace' is the result from initial_cost_nestloop
2447  * 'extra' contains various information about the join
2448  * 'outer_path' is the outer path
2449  * 'inner_path' is the inner path
2450  * 'restrict_clauses' are the RestrictInfo nodes to apply at the join
2451  * 'pathkeys' are the path keys of the new join path
2452  * 'required_outer' is the set of required outer rels
2453  *
2454  * Returns the resulting path node.
2455  */
2456 NestPath *
2458  RelOptInfo *joinrel,
2459  JoinType jointype,
2460  JoinCostWorkspace *workspace,
2461  JoinPathExtraData *extra,
2462  Path *outer_path,
2463  Path *inner_path,
2464  List *restrict_clauses,
2465  List *pathkeys,
2466  Relids required_outer)
2467 {
2468  NestPath *pathnode = makeNode(NestPath);
2469  Relids inner_req_outer = PATH_REQ_OUTER(inner_path);
2470  Relids outerrelids;
2471 
2472  /*
2473  * Paths are parameterized by top-level parents, so run parameterization
2474  * tests on the parent relids.
2475  */
2476  if (outer_path->parent->top_parent_relids)
2477  outerrelids = outer_path->parent->top_parent_relids;
2478  else
2479  outerrelids = outer_path->parent->relids;
2480 
2481  /*
2482  * If the inner path is parameterized by the outer, we must drop any
2483  * restrict_clauses that are due to be moved into the inner path. We have
2484  * to do this now, rather than postpone the work till createplan time,
2485  * because the restrict_clauses list can affect the size and cost
2486  * estimates for this path. We detect such clauses by checking for serial
2487  * number match to clauses already enforced in the inner path.
2488  */
2489  if (bms_overlap(inner_req_outer, outerrelids))
2490  {
2491  Bitmapset *enforced_serials = get_param_path_clause_serials(inner_path);
2492  List *jclauses = NIL;
2493  ListCell *lc;
2494 
2495  foreach(lc, restrict_clauses)
2496  {
2497  RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
2498 
2499  if (!bms_is_member(rinfo->rinfo_serial, enforced_serials))
2500  jclauses = lappend(jclauses, rinfo);
2501  }
2502  restrict_clauses = jclauses;
2503  }
2504 
2505  pathnode->jpath.path.pathtype = T_NestLoop;
2506  pathnode->jpath.path.parent = joinrel;
2507  pathnode->jpath.path.pathtarget = joinrel->reltarget;
2508  pathnode->jpath.path.param_info =
2510  joinrel,
2511  outer_path,
2512  inner_path,
2513  extra->sjinfo,
2514  required_outer,
2515  &restrict_clauses);
2516  pathnode->jpath.path.parallel_aware = false;
2517  pathnode->jpath.path.parallel_safe = joinrel->consider_parallel &&
2518  outer_path->parallel_safe && inner_path->parallel_safe;
2519  /* This is a foolish way to estimate parallel_workers, but for now... */
2520  pathnode->jpath.path.parallel_workers = outer_path->parallel_workers;
2521  pathnode->jpath.path.pathkeys = pathkeys;
2522  pathnode->jpath.jointype = jointype;
2523  pathnode->jpath.inner_unique = extra->inner_unique;
2524  pathnode->jpath.outerjoinpath = outer_path;
2525  pathnode->jpath.innerjoinpath = inner_path;
2526  pathnode->jpath.joinrestrictinfo = restrict_clauses;
2527 
2528  final_cost_nestloop(root, pathnode, workspace, extra);
2529 
2530  return pathnode;
2531 }
2532 
2533 /*
2534  * create_mergejoin_path
2535  * Creates a pathnode corresponding to a mergejoin join between
2536  * two relations
2537  *
2538  * 'joinrel' is the join relation
2539  * 'jointype' is the type of join required
2540  * 'workspace' is the result from initial_cost_mergejoin
2541  * 'extra' contains various information about the join
2542  * 'outer_path' is the outer path
2543  * 'inner_path' is the inner path
2544  * 'restrict_clauses' are the RestrictInfo nodes to apply at the join
2545  * 'pathkeys' are the path keys of the new join path
2546  * 'required_outer' is the set of required outer rels
2547  * 'mergeclauses' are the RestrictInfo nodes to use as merge clauses
2548  * (this should be a subset of the restrict_clauses list)
2549  * 'outersortkeys' are the sort varkeys for the outer relation
2550  * 'innersortkeys' are the sort varkeys for the inner relation
2551  */
2552 MergePath *
2554  RelOptInfo *joinrel,
2555  JoinType jointype,
2556  JoinCostWorkspace *workspace,
2557  JoinPathExtraData *extra,
2558  Path *outer_path,
2559  Path *inner_path,
2560  List *restrict_clauses,
2561  List *pathkeys,
2562  Relids required_outer,
2563  List *mergeclauses,
2564  List *outersortkeys,
2565  List *innersortkeys)
2566 {
2567  MergePath *pathnode = makeNode(MergePath);
2568 
2569  pathnode->jpath.path.pathtype = T_MergeJoin;
2570  pathnode->jpath.path.parent = joinrel;
2571  pathnode->jpath.path.pathtarget = joinrel->reltarget;
2572  pathnode->jpath.path.param_info =
2574  joinrel,
2575  outer_path,
2576  inner_path,
2577  extra->sjinfo,
2578  required_outer,
2579  &restrict_clauses);
2580  pathnode->jpath.path.parallel_aware = false;
2581  pathnode->jpath.path.parallel_safe = joinrel->consider_parallel &&
2582  outer_path->parallel_safe && inner_path->parallel_safe;
2583  /* This is a foolish way to estimate parallel_workers, but for now... */
2584  pathnode->jpath.path.parallel_workers = outer_path->parallel_workers;
2585  pathnode->jpath.path.pathkeys = pathkeys;
2586  pathnode->jpath.jointype = jointype;
2587  pathnode->jpath.inner_unique = extra->inner_unique;
2588  pathnode->jpath.outerjoinpath = outer_path;
2589  pathnode->jpath.innerjoinpath = inner_path;
2590  pathnode->jpath.joinrestrictinfo = restrict_clauses;
2591  pathnode->path_mergeclauses = mergeclauses;
2592  pathnode->outersortkeys = outersortkeys;
2593  pathnode->innersortkeys = innersortkeys;
2594  /* pathnode->skip_mark_restore will be set by final_cost_mergejoin */
2595  /* pathnode->materialize_inner will be set by final_cost_mergejoin */
2596 
2597  final_cost_mergejoin(root, pathnode, workspace, extra);
2598 
2599  return pathnode;
2600 }
2601 
2602 /*
2603  * create_hashjoin_path
2604  * Creates a pathnode corresponding to a hash join between two relations.
2605  *
2606  * 'joinrel' is the join relation
2607  * 'jointype' is the type of join required
2608  * 'workspace' is the result from initial_cost_hashjoin
2609  * 'extra' contains various information about the join
2610  * 'outer_path' is the cheapest outer path
2611  * 'inner_path' is the cheapest inner path
2612  * 'parallel_hash' to select Parallel Hash of inner path (shared hash table)
2613  * 'restrict_clauses' are the RestrictInfo nodes to apply at the join
2614  * 'required_outer' is the set of required outer rels
2615  * 'hashclauses' are the RestrictInfo nodes to use as hash clauses
2616  * (this should be a subset of the restrict_clauses list)
2617  */
2618 HashPath *
2620  RelOptInfo *joinrel,
2621  JoinType jointype,
2622  JoinCostWorkspace *workspace,
2623  JoinPathExtraData *extra,
2624  Path *outer_path,
2625  Path *inner_path,
2626  bool parallel_hash,
2627  List *restrict_clauses,
2628  Relids required_outer,
2629  List *hashclauses)
2630 {
2631  HashPath *pathnode = makeNode(HashPath);
2632 
2633  pathnode->jpath.path.pathtype = T_HashJoin;
2634  pathnode->jpath.path.parent = joinrel;
2635  pathnode->jpath.path.pathtarget = joinrel->reltarget;
2636  pathnode->jpath.path.param_info =
2638  joinrel,
2639  outer_path,
2640  inner_path,
2641  extra->sjinfo,
2642  required_outer,
2643  &restrict_clauses);
2644  pathnode->jpath.path.parallel_aware =
2645  joinrel->consider_parallel && parallel_hash;
2646  pathnode->jpath.path.parallel_safe = joinrel->consider_parallel &&
2647  outer_path->parallel_safe && inner_path->parallel_safe;
2648  /* This is a foolish way to estimate parallel_workers, but for now... */
2649  pathnode->jpath.path.parallel_workers = outer_path->parallel_workers;
2650 
2651  /*
2652  * A hashjoin never has pathkeys, since its output ordering is
2653  * unpredictable due to possible batching. XXX If the inner relation is
2654  * small enough, we could instruct the executor that it must not batch,
2655  * and then we could assume that the output inherits the outer relation's
2656  * ordering, which might save a sort step. However there is considerable
2657  * downside if our estimate of the inner relation size is badly off. For
2658  * the moment we don't risk it. (Note also that if we wanted to take this
2659  * seriously, joinpath.c would have to consider many more paths for the
2660  * outer rel than it does now.)
2661  */
2662  pathnode->jpath.path.pathkeys = NIL;
2663  pathnode->jpath.jointype = jointype;
2664  pathnode->jpath.inner_unique = extra->inner_unique;
2665  pathnode->jpath.outerjoinpath = outer_path;
2666  pathnode->jpath.innerjoinpath = inner_path;
2667  pathnode->jpath.joinrestrictinfo = restrict_clauses;
2668  pathnode->path_hashclauses = hashclauses;
2669  /* final_cost_hashjoin will fill in pathnode->num_batches */
2670 
2671  final_cost_hashjoin(root, pathnode, workspace, extra);
2672 
2673  return pathnode;
2674 }
2675 
2676 /*
2677  * create_projection_path
2678  * Creates a pathnode that represents performing a projection.
2679  *
2680  * 'rel' is the parent relation associated with the result
2681  * 'subpath' is the path representing the source of data
2682  * 'target' is the PathTarget to be computed
2683  */
2686  RelOptInfo *rel,
2687  Path *subpath,
2688  PathTarget *target)
2689 {
2690  ProjectionPath *pathnode = makeNode(ProjectionPath);
2691  PathTarget *oldtarget;
2692 
2693  /*
2694  * We mustn't put a ProjectionPath directly above another; it's useless
2695  * and will confuse create_projection_plan. Rather than making sure all
2696  * callers handle that, let's implement it here, by stripping off any
2697  * ProjectionPath in what we're given. Given this rule, there won't be
2698  * more than one.
2699  */
2700  if (IsA(subpath, ProjectionPath))
2701  {
2702  ProjectionPath *subpp = (ProjectionPath *) subpath;
2703 
2704  Assert(subpp->path.parent == rel);
2705  subpath = subpp->subpath;
2707  }
2708 
2709  pathnode->path.pathtype = T_Result;
2710  pathnode->path.parent = rel;
2711  pathnode->path.pathtarget = target;
2712  /* For now, assume we are above any joins, so no parameterization */
2713  pathnode->path.param_info = NULL;
2714  pathnode->path.parallel_aware = false;
2715  pathnode->path.parallel_safe = rel->consider_parallel &&
2716  subpath->parallel_safe &&
2717  is_parallel_safe(root, (Node *) target->exprs);
2718  pathnode->path.parallel_workers = subpath->parallel_workers;
2719  /* Projection does not change the sort order */
2720  pathnode->path.pathkeys = subpath->pathkeys;
2721 
2722  pathnode->subpath = subpath;
2723 
2724  /*
2725  * We might not need a separate Result node. If the input plan node type
2726  * can project, we can just tell it to project something else. Or, if it
2727  * can't project but the desired target has the same expression list as
2728  * what the input will produce anyway, we can still give it the desired
2729  * tlist (possibly changing its ressortgroupref labels, but nothing else).
2730  * Note: in the latter case, create_projection_plan has to recheck our
2731  * conclusion; see comments therein.
2732  */
2733  oldtarget = subpath->pathtarget;
2735  equal(oldtarget->exprs, target->exprs))
2736  {
2737  /* No separate Result node needed */
2738  pathnode->dummypp = true;
2739 
2740  /*
2741  * Set cost of plan as subpath's cost, adjusted for tlist replacement.
2742  */
2743  pathnode->path.rows = subpath->rows;
2744  pathnode->path.startup_cost = subpath->startup_cost +
2745  (target->cost.startup - oldtarget->cost.startup);
2746  pathnode->path.total_cost = subpath->total_cost +
2747  (target->cost.startup - oldtarget->cost.startup) +
2748  (target->cost.per_tuple - oldtarget->cost.per_tuple) * subpath->rows;
2749  }
2750  else
2751  {
2752  /* We really do need the Result node */
2753  pathnode->dummypp = false;
2754 
2755  /*
2756  * The Result node's cost is cpu_tuple_cost per row, plus the cost of
2757  * evaluating the tlist. There is no qual to worry about.
2758  */
2759  pathnode->path.rows = subpath->rows;
2760  pathnode->path.startup_cost = subpath->startup_cost +
2761  target->cost.startup;
2762  pathnode->path.total_cost = subpath->total_cost +
2763  target->cost.startup +
2764  (cpu_tuple_cost + target->cost.per_tuple) * subpath->rows;
2765  }
2766 
2767  return pathnode;
2768 }
2769 
2770 /*
2771  * apply_projection_to_path
2772  * Add a projection step, or just apply the target directly to given path.
2773  *
2774  * This has the same net effect as create_projection_path(), except that if
2775  * a separate Result plan node isn't needed, we just replace the given path's
2776  * pathtarget with the desired one. This must be used only when the caller
2777  * knows that the given path isn't referenced elsewhere and so can be modified
2778  * in-place.
2779  *
2780  * If the input path is a GatherPath or GatherMergePath, we try to push the
2781  * new target down to its input as well; this is a yet more invasive
2782  * modification of the input path, which create_projection_path() can't do.
2783  *
2784  * Note that we mustn't change the source path's parent link; so when it is
2785  * add_path'd to "rel" things will be a bit inconsistent. So far that has
2786  * not caused any trouble.
2787  *
2788  * 'rel' is the parent relation associated with the result
2789  * 'path' is the path representing the source of data
2790  * 'target' is the PathTarget to be computed
2791  */
2792 Path *
2794  RelOptInfo *rel,
2795  Path *path,
2796  PathTarget *target)
2797 {
2798  QualCost oldcost;
2799 
2800  /*
2801  * If given path can't project, we might need a Result node, so make a
2802  * separate ProjectionPath.
2803  */
2804  if (!is_projection_capable_path(path))
2805  return (Path *) create_projection_path(root, rel, path, target);
2806 
2807  /*
2808  * We can just jam the desired tlist into the existing path, being sure to
2809  * update its cost estimates appropriately.
2810  */
2811  oldcost = path->pathtarget->cost;
2812  path->pathtarget = target;
2813 
2814  path->startup_cost += target->cost.startup - oldcost.startup;
2815  path->total_cost += target->cost.startup - oldcost.startup +
2816  (target->cost.per_tuple - oldcost.per_tuple) * path->rows;
2817 
2818  /*
2819  * If the path happens to be a Gather or GatherMerge path, we'd like to
2820  * arrange for the subpath to return the required target list so that
2821  * workers can help project. But if there is something that is not
2822  * parallel-safe in the target expressions, then we can't.
2823  */
2824  if ((IsA(path, GatherPath) || IsA(path, GatherMergePath)) &&
2825  is_parallel_safe(root, (Node *) target->exprs))
2826  {
2827  /*
2828  * We always use create_projection_path here, even if the subpath is
2829  * projection-capable, so as to avoid modifying the subpath in place.
2830  * It seems unlikely at present that there could be any other
2831  * references to the subpath, but better safe than sorry.
2832  *
2833  * Note that we don't change the parallel path's cost estimates; it
2834  * might be appropriate to do so, to reflect the fact that the bulk of
2835  * the target evaluation will happen in workers.
2836  */
2837  if (IsA(path, GatherPath))
2838  {
2839  GatherPath *gpath = (GatherPath *) path;
2840 
2841  gpath->subpath = (Path *)
2843  gpath->subpath->parent,
2844  gpath->subpath,
2845  target);
2846  }
2847  else
2848  {
2849  GatherMergePath *gmpath = (GatherMergePath *) path;
2850 
2851  gmpath->subpath = (Path *)
2853  gmpath->subpath->parent,
2854  gmpath->subpath,
2855  target);
2856  }
2857  }
2858  else if (path->parallel_safe &&
2859  !is_parallel_safe(root, (Node *) target->exprs))
2860  {
2861  /*
2862  * We're inserting a parallel-restricted target list into a path
2863  * currently marked parallel-safe, so we have to mark it as no longer
2864  * safe.
2865  */
2866  path->parallel_safe = false;
2867  }
2868 
2869  return path;
2870 }
2871 
2872 /*
2873  * create_set_projection_path
2874  * Creates a pathnode that represents performing a projection that
2875  * includes set-returning functions.
2876  *
2877  * 'rel' is the parent relation associated with the result
2878  * 'subpath' is the path representing the source of data
2879  * 'target' is the PathTarget to be computed
2880  */
2883  RelOptInfo *rel,
2884  Path *subpath,
2885  PathTarget *target)
2886 {
2887  ProjectSetPath *pathnode = makeNode(ProjectSetPath);
2888  double tlist_rows;
2889  ListCell *lc;
2890 
2891  pathnode->path.pathtype = T_ProjectSet;
2892  pathnode->path.parent = rel;
2893  pathnode->path.pathtarget = target;
2894  /* For now, assume we are above any joins, so no parameterization */
2895  pathnode->path.param_info = NULL;
2896  pathnode->path.parallel_aware = false;
2897  pathnode->path.parallel_safe = rel->consider_parallel &&
2898  subpath->parallel_safe &&
2899  is_parallel_safe(root, (Node *) target->exprs);
2900  pathnode->path.parallel_workers = subpath->parallel_workers;
2901  /* Projection does not change the sort order XXX? */
2902  pathnode->path.pathkeys = subpath->pathkeys;
2903 
2904  pathnode->subpath = subpath;
2905 
2906  /*
2907  * Estimate number of rows produced by SRFs for each row of input; if
2908  * there's more than one in this node, use the maximum.
2909  */
2910  tlist_rows = 1;
2911  foreach(lc, target->exprs)
2912  {
2913  Node *node = (Node *) lfirst(lc);
2914  double itemrows;
2915 
2916  itemrows = expression_returns_set_rows(root, node);
2917  if (tlist_rows < itemrows)
2918  tlist_rows = itemrows;
2919  }
2920 
2921  /*
2922  * In addition to the cost of evaluating the tlist, charge cpu_tuple_cost
2923  * per input row, and half of cpu_tuple_cost for each added output row.
2924  * This is slightly bizarre maybe, but it's what 9.6 did; we may revisit
2925  * this estimate later.
2926  */
2927  pathnode->path.rows = subpath->rows * tlist_rows;
2928  pathnode->path.startup_cost = subpath->startup_cost +
2929  target->cost.startup;
2930  pathnode->path.total_cost = subpath->total_cost +
2931  target->cost.startup +
2932  (cpu_tuple_cost + target->cost.per_tuple) * subpath->rows +
2933  (pathnode->path.rows - subpath->rows) * cpu_tuple_cost / 2;
2934 
2935  return pathnode;
2936 }
2937 
2938 /*
2939  * create_incremental_sort_path
2940  * Creates a pathnode that represents performing an incremental sort.
2941  *
2942  * 'rel' is the parent relation associated with the result
2943  * 'subpath' is the path representing the source of data
2944  * 'pathkeys' represents the desired sort order
2945  * 'presorted_keys' is the number of keys by which the input path is
2946  * already sorted
2947  * 'limit_tuples' is the estimated bound on the number of output tuples,
2948  * or -1 if no LIMIT or couldn't estimate
2949  */
2952  RelOptInfo *rel,
2953  Path *subpath,
2954  List *pathkeys,
2955  int presorted_keys,
2956  double limit_tuples)
2957 {
2959  SortPath *pathnode = &sort->spath;
2960 
2961  pathnode->path.pathtype = T_IncrementalSort;
2962  pathnode->path.parent = rel;
2963  /* Sort doesn't project, so use source path's pathtarget */
2964  pathnode->path.pathtarget = subpath->pathtarget;
2965  /* For now, assume we are above any joins, so no parameterization */
2966  pathnode->path.param_info = NULL;
2967  pathnode->path.parallel_aware = false;
2968  pathnode->path.parallel_safe = rel->consider_parallel &&
2969  subpath->parallel_safe;
2970  pathnode->path.parallel_workers = subpath->parallel_workers;
2971  pathnode->path.pathkeys = pathkeys;
2972 
2973  pathnode->subpath = subpath;
2974 
2975  cost_incremental_sort(&pathnode->path,
2976  root, pathkeys, presorted_keys,
2977  subpath->startup_cost,
2978  subpath->total_cost,
2979  subpath->rows,
2980  subpath->pathtarget->width,
2981  0.0, /* XXX comparison_cost shouldn't be 0? */
2982  work_mem, limit_tuples);
2983 
2984  sort->nPresortedCols = presorted_keys;
2985 
2986  return sort;
2987 }
2988 
2989 /*
2990  * create_sort_path
2991  * Creates a pathnode that represents performing an explicit sort.
2992  *
2993  * 'rel' is the parent relation associated with the result
2994  * 'subpath' is the path representing the source of data
2995  * 'pathkeys' represents the desired sort order
2996  * 'limit_tuples' is the estimated bound on the number of output tuples,
2997  * or -1 if no LIMIT or couldn't estimate
2998  */
2999 SortPath *
3001  RelOptInfo *rel,
3002  Path *subpath,
3003  List *pathkeys,
3004  double limit_tuples)
3005 {
3006  SortPath *pathnode = makeNode(SortPath);
3007 
3008  pathnode->path.pathtype = T_Sort;
3009  pathnode->path.parent = rel;
3010  /* Sort doesn't project, so use source path's pathtarget */
3011  pathnode->path.pathtarget = subpath->pathtarget;
3012  /* For now, assume we are above any joins, so no parameterization */
3013  pathnode->path.param_info = NULL;
3014  pathnode->path.parallel_aware = false;
3015  pathnode->path.parallel_safe = rel->consider_parallel &&
3016  subpath->parallel_safe;
3017  pathnode->path.parallel_workers = subpath->parallel_workers;
3018  pathnode->path.pathkeys = pathkeys;
3019 
3020  pathnode->subpath = subpath;
3021 
3022  cost_sort(&pathnode->path, root, pathkeys,
3023  subpath->total_cost,
3024  subpath->rows,
3025  subpath->pathtarget->width,
3026  0.0, /* XXX comparison_cost shouldn't be 0? */
3027  work_mem, limit_tuples);
3028 
3029  return pathnode;
3030 }
3031 
3032 /*
3033  * create_group_path
3034  * Creates a pathnode that represents performing grouping of presorted input
3035  *
3036  * 'rel' is the parent relation associated with the result
3037  * 'subpath' is the path representing the source of data
3038  * 'target' is the PathTarget to be computed
3039  * 'groupClause' is a list of SortGroupClause's representing the grouping
3040  * 'qual' is the HAVING quals if any
3041  * 'numGroups' is the estimated number of groups
3042  */
3043 GroupPath *
3045  RelOptInfo *rel,
3046  Path *subpath,
3047  List *groupClause,
3048  List *qual,
3049  double numGroups)
3050 {
3051  GroupPath *pathnode = makeNode(GroupPath);
3052  PathTarget *target = rel->reltarget;
3053 
3054  pathnode->path.pathtype = T_Group;
3055  pathnode->path.parent = rel;
3056  pathnode->path.pathtarget = target;
3057  /* For now, assume we are above any joins, so no parameterization */
3058  pathnode->path.param_info = NULL;
3059  pathnode->path.parallel_aware = false;
3060  pathnode->path.parallel_safe = rel->consider_parallel &&
3061  subpath->parallel_safe;
3062  pathnode->path.parallel_workers = subpath->parallel_workers;
3063  /* Group doesn't change sort ordering */
3064  pathnode->path.pathkeys = subpath->pathkeys;
3065 
3066  pathnode->subpath = subpath;
3067 
3068  pathnode->groupClause = groupClause;
3069  pathnode->qual = qual;
3070 
3071  cost_group(&pathnode->path, root,
3072  list_length(groupClause),
3073  numGroups,
3074  qual,
3075  subpath->startup_cost, subpath->total_cost,
3076  subpath->rows);
3077 
3078  /* add tlist eval cost for each output row */
3079  pathnode->path.startup_cost += target->cost.startup;
3080  pathnode->path.total_cost += target->cost.startup +
3081  target->cost.per_tuple * pathnode->path.rows;
3082 
3083  return pathnode;
3084 }
3085 
3086 /*
3087  * create_upper_unique_path
3088  * Creates a pathnode that represents performing an explicit Unique step
3089  * on presorted input.
3090  *
3091  * This produces a Unique plan node, but the use-case is so different from
3092  * create_unique_path that it doesn't seem worth trying to merge the two.
3093  *
3094  * 'rel' is the parent relation associated with the result
3095  * 'subpath' is the path representing the source of data
3096  * 'numCols' is the number of grouping columns
3097  * 'numGroups' is the estimated number of groups
3098  *
3099  * The input path must be sorted on the grouping columns, plus possibly
3100  * additional columns; so the first numCols pathkeys are the grouping columns
3101  */
3104  RelOptInfo *rel,
3105  Path *subpath,
3106  int numCols,
3107  double numGroups)
3108 {
3110 
3111  pathnode->path.pathtype = T_Unique;
3112  pathnode->path.parent = rel;
3113  /* Unique doesn't project, so use source path's pathtarget */
3114  pathnode->path.pathtarget = subpath->pathtarget;
3115  /* For now, assume we are above any joins, so no parameterization */
3116  pathnode->path.param_info = NULL;
3117  pathnode->path.parallel_aware = false;
3118  pathnode->path.parallel_safe = rel->consider_parallel &&
3119  subpath->parallel_safe;
3120  pathnode->path.parallel_workers = subpath->parallel_workers;
3121  /* Unique doesn't change the input ordering */
3122  pathnode->path.pathkeys = subpath->pathkeys;
3123 
3124  pathnode->subpath = subpath;
3125  pathnode->numkeys = numCols;
3126 
3127  /*
3128  * Charge one cpu_operator_cost per comparison per input tuple. We assume
3129  * all columns get compared at most of the tuples. (XXX probably this is
3130  * an overestimate.)
3131  */
3132  pathnode->path.startup_cost = subpath->startup_cost;
3133  pathnode->path.total_cost = subpath->total_cost +
3134  cpu_operator_cost * subpath->rows * numCols;
3135  pathnode->path.rows = numGroups;
3136 
3137  return pathnode;
3138 }
3139 
3140 /*
3141  * create_agg_path
3142  * Creates a pathnode that represents performing aggregation/grouping
3143  *
3144  * 'rel' is the parent relation associated with the result
3145  * 'subpath' is the path representing the source of data
3146  * 'target' is the PathTarget to be computed
3147  * 'aggstrategy' is the Agg node's basic implementation strategy
3148  * 'aggsplit' is the Agg node's aggregate-splitting mode
3149  * 'groupClause' is a list of SortGroupClause's representing the grouping
3150  * 'qual' is the HAVING quals if any
3151  * 'aggcosts' contains cost info about the aggregate functions to be computed
3152  * 'numGroups' is the estimated number of groups (1 if not grouping)
3153  */
3154 AggPath *
3156  RelOptInfo *rel,
3157  Path *subpath,
3158  PathTarget *target,
3159  AggStrategy aggstrategy,
3160  AggSplit aggsplit,
3161  List *groupClause,
3162  List *qual,
3163  const AggClauseCosts *aggcosts,
3164  double numGroups)
3165 {
3166  AggPath *pathnode = makeNode(AggPath);
3167 
3168  pathnode->path.pathtype = T_Agg;
3169  pathnode->path.parent = rel;
3170  pathnode->path.pathtarget = target;
3171  /* For now, assume we are above any joins, so no parameterization */
3172  pathnode->path.param_info = NULL;
3173  pathnode->path.parallel_aware = false;
3174  pathnode->path.parallel_safe = rel->consider_parallel &&
3175  subpath->parallel_safe;
3176  pathnode->path.parallel_workers = subpath->parallel_workers;
3177 
3178  if (aggstrategy == AGG_SORTED)
3179  {
3180  /*
3181  * Attempt to preserve the order of the subpath. Additional pathkeys
3182  * may have been added in adjust_group_pathkeys_for_groupagg() to
3183  * support ORDER BY / DISTINCT aggregates. Pathkeys added there
3184  * belong to columns within the aggregate function, so we must strip
3185  * these additional pathkeys off as those columns are unavailable
3186  * above the aggregate node.
3187  */
3188  if (list_length(subpath->pathkeys) > root->num_groupby_pathkeys)
3189  pathnode->path.pathkeys = list_copy_head(subpath->pathkeys,
3190  root->num_groupby_pathkeys);
3191  else
3192  pathnode->path.pathkeys = subpath->pathkeys; /* preserves order */
3193  }
3194  else
3195  pathnode->path.pathkeys = NIL; /* output is unordered */
3196 
3197  pathnode->subpath = subpath;
3198 
3199  pathnode->aggstrategy = aggstrategy;
3200  pathnode->aggsplit = aggsplit;
3201  pathnode->numGroups = numGroups;
3202  pathnode->transitionSpace = aggcosts ? aggcosts->transitionSpace : 0;
3203  pathnode->groupClause = groupClause;
3204  pathnode->qual = qual;
3205 
3206  cost_agg(&pathnode->path, root,
3207  aggstrategy, aggcosts,
3208  list_length(groupClause), numGroups,
3209  qual,
3210  subpath->startup_cost, subpath->total_cost,
3211  subpath->rows, subpath->pathtarget->width);
3212 
3213  /* add tlist eval cost for each output row */
3214  pathnode->path.startup_cost += target->cost.startup;
3215  pathnode->path.total_cost += target->cost.startup +
3216  target->cost.per_tuple * pathnode->path.rows;
3217 
3218  return pathnode;
3219 }
3220 
3221 /*
3222  * create_groupingsets_path
3223  * Creates a pathnode that represents performing GROUPING SETS aggregation
3224  *
3225  * GroupingSetsPath represents sorted grouping with one or more grouping sets.
3226  * The input path's result must be sorted to match the last entry in
3227  * rollup_groupclauses.
3228  *
3229  * 'rel' is the parent relation associated with the result
3230  * 'subpath' is the path representing the source of data
3231  * 'target' is the PathTarget to be computed
3232  * 'having_qual' is the HAVING quals if any
3233  * 'rollups' is a list of RollupData nodes
3234  * 'agg_costs' contains cost info about the aggregate functions to be computed
3235  */
3238  RelOptInfo *rel,
3239  Path *subpath,
3240  List *having_qual,
3241  AggStrategy aggstrategy,
3242  List *rollups,
3243  const AggClauseCosts *agg_costs)
3244 {
3246  PathTarget *target = rel->reltarget;
3247  ListCell *lc;
3248  bool is_first = true;
3249  bool is_first_sort = true;
3250 
3251  /* The topmost generated Plan node will be an Agg */
3252  pathnode->path.pathtype = T_Agg;
3253  pathnode->path.parent = rel;
3254  pathnode->path.pathtarget = target;
3255  pathnode->path.param_info = subpath->param_info;
3256  pathnode->path.parallel_aware = false;
3257  pathnode->path.parallel_safe = rel->consider_parallel &&
3258  subpath->parallel_safe;
3259  pathnode->path.parallel_workers = subpath->parallel_workers;
3260  pathnode->subpath = subpath;
3261 
3262  /*
3263  * Simplify callers by downgrading AGG_SORTED to AGG_PLAIN, and AGG_MIXED
3264  * to AGG_HASHED, here if possible.
3265  */
3266  if (aggstrategy == AGG_SORTED &&
3267  list_length(rollups) == 1 &&
3268  ((RollupData *) linitial(rollups))->groupClause == NIL)
3269  aggstrategy = AGG_PLAIN;
3270 
3271  if (aggstrategy == AGG_MIXED &&
3272  list_length(rollups) == 1)
3273  aggstrategy = AGG_HASHED;
3274 
3275  /*
3276  * Output will be in sorted order by group_pathkeys if, and only if, there
3277  * is a single rollup operation on a non-empty list of grouping
3278  * expressions.
3279  */
3280  if (aggstrategy == AGG_SORTED && list_length(rollups) == 1)
3281  pathnode->path.pathkeys = root->group_pathkeys;
3282  else
3283  pathnode->path.pathkeys = NIL;
3284 
3285  pathnode->aggstrategy = aggstrategy;
3286  pathnode->rollups = rollups;
3287  pathnode->qual = having_qual;
3288  pathnode->transitionSpace = agg_costs ? agg_costs->transitionSpace : 0;
3289 
3290  Assert(rollups != NIL);
3291  Assert(aggstrategy != AGG_PLAIN || list_length(rollups) == 1);
3292  Assert(aggstrategy != AGG_MIXED || list_length(rollups) > 1);
3293 
3294  foreach(lc, rollups)
3295  {
3296  RollupData *rollup = lfirst(lc);
3297  List *gsets = rollup->gsets;
3298  int numGroupCols = list_length(linitial(gsets));
3299 
3300  /*
3301  * In AGG_SORTED or AGG_PLAIN mode, the first rollup takes the
3302  * (already-sorted) input, and following ones do their own sort.
3303  *
3304  * In AGG_HASHED mode, there is one rollup for each grouping set.
3305  *
3306  * In AGG_MIXED mode, the first rollups are hashed, the first
3307  * non-hashed one takes the (already-sorted) input, and following ones
3308  * do their own sort.
3309  */
3310  if (is_first)
3311  {
3312  cost_agg(&pathnode->path, root,
3313  aggstrategy,
3314  agg_costs,
3315  numGroupCols,
3316  rollup->numGroups,
3317  having_qual,
3318  subpath->startup_cost,
3319  subpath->total_cost,
3320  subpath->rows,
3321  subpath->pathtarget->width);
3322  is_first = false;
3323  if (!rollup->is_hashed)
3324  is_first_sort = false;
3325  }
3326  else
3327  {
3328  Path sort_path; /* dummy for result of cost_sort */
3329  Path agg_path; /* dummy for result of cost_agg */
3330 
3331  if (rollup->is_hashed || is_first_sort)
3332  {
3333  /*
3334  * Account for cost of aggregation, but don't charge input
3335  * cost again
3336  */
3337  cost_agg(&agg_path, root,
3338  rollup->is_hashed ? AGG_HASHED : AGG_SORTED,
3339  agg_costs,
3340  numGroupCols,
3341  rollup->numGroups,
3342  having_qual,
3343  0.0, 0.0,
3344  subpath->rows,
3345  subpath->pathtarget->width);
3346  if (!rollup->is_hashed)
3347  is_first_sort = false;
3348  }
3349  else
3350  {
3351  /* Account for cost of sort, but don't charge input cost again */
3352  cost_sort(&sort_path, root, NIL,
3353  0.0,
3354  subpath->rows,
3355  subpath->pathtarget->width,
3356  0.0,
3357  work_mem,
3358  -1.0);
3359 
3360  /* Account for cost of aggregation */
3361 
3362  cost_agg(&agg_path, root,
3363  AGG_SORTED,
3364  agg_costs,
3365  numGroupCols,
3366  rollup->numGroups,
3367  having_qual,
3368  sort_path.startup_cost,
3369  sort_path.total_cost,
3370  sort_path.rows,
3371  subpath->pathtarget->width);
3372  }
3373 
3374  pathnode->path.total_cost += agg_path.total_cost;
3375  pathnode->path.rows += agg_path.rows;
3376  }
3377  }
3378 
3379  /* add tlist eval cost for each output row */
3380  pathnode->path.startup_cost += target->cost.startup;
3381  pathnode->path.total_cost += target->cost.startup +
3382  target->cost.per_tuple * pathnode->path.rows;
3383 
3384  return pathnode;
3385 }
3386 
3387 /*
3388  * create_minmaxagg_path
3389  * Creates a pathnode that represents computation of MIN/MAX aggregates
3390  *
3391  * 'rel' is the parent relation associated with the result
3392  * 'target' is the PathTarget to be computed
3393  * 'mmaggregates' is a list of MinMaxAggInfo structs
3394  * 'quals' is the HAVING quals if any
3395  */
3396 MinMaxAggPath *
3398  RelOptInfo *rel,
3399  PathTarget *target,
3400  List *mmaggregates,
3401  List *quals)
3402 {
3403  MinMaxAggPath *pathnode = makeNode(MinMaxAggPath);
3404  Cost initplan_cost;
3405  ListCell *lc;
3406 
3407  /* The topmost generated Plan node will be a Result */
3408  pathnode->path.pathtype = T_Result;
3409  pathnode->path.parent = rel;
3410  pathnode->path.pathtarget = target;
3411  /* For now, assume we are above any joins, so no parameterization */
3412  pathnode->path.param_info = NULL;
3413  pathnode->path.parallel_aware = false;
3414  pathnode->path.parallel_safe = true; /* might change below */
3415  pathnode->path.parallel_workers = 0;
3416  /* Result is one unordered row */
3417  pathnode->path.rows = 1;
3418  pathnode->path.pathkeys = NIL;
3419 
3420  pathnode->mmaggregates = mmaggregates;
3421  pathnode->quals = quals;
3422 
3423  /* Calculate cost of all the initplans, and check parallel safety */
3424  initplan_cost = 0;
3425  foreach(lc, mmaggregates)
3426  {
3427  MinMaxAggInfo *mminfo = (MinMaxAggInfo *) lfirst(lc);
3428 
3429  initplan_cost += mminfo->pathcost;
3430  if (!mminfo->path->parallel_safe)
3431  pathnode->path.parallel_safe = false;
3432  }
3433 
3434  /* add tlist eval cost for each output row, plus cpu_tuple_cost */
3435  pathnode->path.startup_cost = initplan_cost + target->cost.startup;
3436  pathnode->path.total_cost = initplan_cost + target->cost.startup +
3437  target->cost.per_tuple + cpu_tuple_cost;
3438 
3439  /*
3440  * Add cost of qual, if any --- but we ignore its selectivity, since our
3441  * rowcount estimate should be 1 no matter what the qual is.
3442  */
3443  if (quals)
3444  {
3445  QualCost qual_cost;
3446 
3447  cost_qual_eval(&qual_cost, quals, root);
3448  pathnode->path.startup_cost += qual_cost.startup;
3449  pathnode->path.total_cost += qual_cost.startup + qual_cost.per_tuple;
3450  }
3451 
3452  /*
3453  * If the initplans were all parallel-safe, also check safety of the
3454  * target and quals. (The Result node itself isn't parallelizable, but if
3455  * we are in a subquery then it can be useful for the outer query to know
3456  * that this one is parallel-safe.)
3457  */
3458  if (pathnode->path.parallel_safe)
3459  pathnode->path.parallel_safe =
3460  is_parallel_safe(root, (Node *) target->exprs) &&
3461  is_parallel_safe(root, (Node *) quals);
3462 
3463  return pathnode;
3464 }
3465 
3466 /*
3467  * create_windowagg_path
3468  * Creates a pathnode that represents computation of window functions
3469  *
3470  * 'rel' is the parent relation associated with the result
3471  * 'subpath' is the path representing the source of data
3472  * 'target' is the PathTarget to be computed
3473  * 'windowFuncs' is a list of WindowFunc structs
3474  * 'runCondition' is a list of OpExprs to short-circuit WindowAgg execution
3475  * 'winclause' is a WindowClause that is common to all the WindowFuncs
3476  * 'qual' WindowClause.runconditions from lower-level WindowAggPaths.
3477  * Must always be NIL when topwindow == false
3478  * 'topwindow' pass as true only for the top-level WindowAgg. False for all
3479  * intermediate WindowAggs.
3480  *
3481  * The input must be sorted according to the WindowClause's PARTITION keys
3482  * plus ORDER BY keys.
3483  */
3484 WindowAggPath *
3486  RelOptInfo *rel,
3487  Path *subpath,
3488  PathTarget *target,
3489  List *windowFuncs,
3490  List *runCondition,
3491  WindowClause *winclause,
3492  List *qual,
3493  bool topwindow)
3494 {
3495  WindowAggPath *pathnode = makeNode(WindowAggPath);
3496 
3497  /* qual can only be set for the topwindow */
3498  Assert(qual == NIL || topwindow);
3499 
3500  pathnode->path.pathtype = T_WindowAgg;
3501  pathnode->path.parent = rel;
3502  pathnode->path.pathtarget = target;
3503  /* For now, assume we are above any joins, so no parameterization */
3504  pathnode->path.param_info = NULL;
3505  pathnode->path.parallel_aware = false;
3506  pathnode->path.parallel_safe = rel->consider_parallel &&
3507  subpath->parallel_safe;
3508  pathnode->path.parallel_workers = subpath->parallel_workers;
3509  /* WindowAgg preserves the input sort order */
3510  pathnode->path.pathkeys = subpath->pathkeys;
3511 
3512  pathnode->subpath = subpath;
3513  pathnode->winclause = winclause;
3514  pathnode->qual = qual;
3515  pathnode->runCondition = runCondition;
3516  pathnode->topwindow = topwindow;
3517 
3518  /*
3519  * For costing purposes, assume that there are no redundant partitioning
3520  * or ordering columns; it's not worth the trouble to deal with that
3521  * corner case here. So we just pass the unmodified list lengths to
3522  * cost_windowagg.
3523  */
3524  cost_windowagg(&pathnode->path, root,
3525  windowFuncs,
3526  winclause,
3527  subpath->startup_cost,
3528  subpath->total_cost,
3529  subpath->rows);
3530 
3531  /* add tlist eval cost for each output row */
3532  pathnode->path.startup_cost += target->cost.startup;
3533  pathnode->path.total_cost += target->cost.startup +
3534  target->cost.per_tuple * pathnode->path.rows;
3535 
3536  return pathnode;
3537 }
3538 
3539 /*
3540  * create_setop_path
3541  * Creates a pathnode that represents computation of INTERSECT or EXCEPT
3542  *
3543  * 'rel' is the parent relation associated with the result
3544  * 'subpath' is the path representing the source of data
3545  * 'cmd' is the specific semantics (INTERSECT or EXCEPT, with/without ALL)
3546  * 'strategy' is the implementation strategy (sorted or hashed)
3547  * 'distinctList' is a list of SortGroupClause's representing the grouping
3548  * 'flagColIdx' is the column number where the flag column will be, if any
3549  * 'firstFlag' is the flag value for the first input relation when hashing;
3550  * or -1 when sorting
3551  * 'numGroups' is the estimated number of distinct groups
3552  * 'outputRows' is the estimated number of output rows
3553  */
3554 SetOpPath *
3556  RelOptInfo *rel,
3557  Path *subpath,
3558  SetOpCmd cmd,
3559  SetOpStrategy strategy,
3560  List *distinctList,
3561  AttrNumber flagColIdx,
3562  int firstFlag,
3563  double numGroups,
3564  double outputRows)
3565 {
3566  SetOpPath *pathnode = makeNode(SetOpPath);
3567 
3568  pathnode->path.pathtype = T_SetOp;
3569  pathnode->path.parent = rel;
3570  /* SetOp doesn't project, so use source path's pathtarget */
3571  pathnode->path.pathtarget = subpath->pathtarget;
3572  /* For now, assume we are above any joins, so no parameterization */
3573  pathnode->path.param_info = NULL;
3574  pathnode->path.parallel_aware = false;
3575  pathnode->path.parallel_safe = rel->consider_parallel &&
3576  subpath->parallel_safe;
3577  pathnode->path.parallel_workers = subpath->parallel_workers;
3578  /* SetOp preserves the input sort order if in sort mode */
3579  pathnode->path.pathkeys =
3580  (strategy == SETOP_SORTED) ? subpath->pathkeys : NIL;
3581 
3582  pathnode->subpath = subpath;
3583  pathnode->cmd = cmd;
3584  pathnode->strategy = strategy;
3585  pathnode->distinctList = distinctList;
3586  pathnode->flagColIdx = flagColIdx;
3587  pathnode->firstFlag = firstFlag;
3588  pathnode->numGroups = numGroups;
3589 
3590  /*
3591  * Charge one cpu_operator_cost per comparison per input tuple. We assume
3592  * all columns get compared at most of the tuples.
3593  */
3594  pathnode->path.startup_cost = subpath->startup_cost;
3595  pathnode->path.total_cost = subpath->total_cost +
3596  cpu_operator_cost * subpath->rows * list_length(distinctList);
3597  pathnode->path.rows = outputRows;
3598 
3599  return pathnode;
3600 }
3601 
3602 /*
3603  * create_recursiveunion_path
3604  * Creates a pathnode that represents a recursive UNION node
3605  *
3606  * 'rel' is the parent relation associated with the result
3607  * 'leftpath' is the source of data for the non-recursive term
3608  * 'rightpath' is the source of data for the recursive term
3609  * 'target' is the PathTarget to be computed
3610  * 'distinctList' is a list of SortGroupClause's representing the grouping
3611  * 'wtParam' is the ID of Param representing work table
3612  * 'numGroups' is the estimated number of groups
3613  *
3614  * For recursive UNION ALL, distinctList is empty and numGroups is zero
3615  */
3618  RelOptInfo *rel,
3619  Path *leftpath,
3620  Path *rightpath,
3621  PathTarget *target,
3622  List *distinctList,
3623  int wtParam,
3624  double numGroups)
3625 {
3627 
3628  pathnode->path.pathtype = T_RecursiveUnion;
3629  pathnode->path.parent = rel;
3630  pathnode->path.pathtarget = target;
3631  /* For now, assume we are above any joins, so no parameterization */
3632  pathnode->path.param_info = NULL;
3633  pathnode->path.parallel_aware = false;
3634  pathnode->path.parallel_safe = rel->consider_parallel &&
3635  leftpath->parallel_safe && rightpath->parallel_safe;
3636  /* Foolish, but we'll do it like joins for now: */
3637  pathnode->path.parallel_workers = leftpath->parallel_workers;
3638  /* RecursiveUnion result is always unsorted */
3639  pathnode->path.pathkeys = NIL;
3640 
3641  pathnode->leftpath = leftpath;
3642  pathnode->rightpath = rightpath;
3643  pathnode->distinctList = distinctList;
3644  pathnode->wtParam = wtParam;
3645  pathnode->numGroups = numGroups;
3646 
3647  cost_recursive_union(&pathnode->path, leftpath, rightpath);
3648 
3649  return pathnode;
3650 }
3651 
3652 /*
3653  * create_lockrows_path
3654  * Creates a pathnode that represents acquiring row locks
3655  *
3656  * 'rel' is the parent relation associated with the result
3657  * 'subpath' is the path representing the source of data
3658  * 'rowMarks' is a list of PlanRowMark's
3659  * 'epqParam' is the ID of Param for EvalPlanQual re-eval
3660  */
3661 LockRowsPath *
3663  Path *subpath, List *rowMarks, int epqParam)
3664 {
3665  LockRowsPath *pathnode = makeNode(LockRowsPath);
3666 
3667  pathnode->path.pathtype = T_LockRows;
3668  pathnode->path.parent = rel;
3669  /* LockRows doesn't project, so use source path's pathtarget */
3670  pathnode->path.pathtarget = subpath->pathtarget;
3671  /* For now, assume we are above any joins, so no parameterization */
3672  pathnode->path.param_info = NULL;
3673  pathnode->path.parallel_aware = false;
3674  pathnode->path.parallel_safe = false;
3675  pathnode->path.parallel_workers = 0;
3676  pathnode->path.rows = subpath->rows;
3677 
3678  /*
3679  * The result cannot be assumed sorted, since locking might cause the sort
3680  * key columns to be replaced with new values.
3681  */
3682  pathnode->path.pathkeys = NIL;
3683 
3684  pathnode->subpath = subpath;
3685  pathnode->rowMarks = rowMarks;
3686  pathnode->epqParam = epqParam;
3687 
3688  /*
3689  * We should charge something extra for the costs of row locking and
3690  * possible refetches, but it's hard to say how much. For now, use
3691  * cpu_tuple_cost per row.
3692  */
3693  pathnode->path.startup_cost = subpath->startup_cost;
3694  pathnode->path.total_cost = subpath->total_cost +
3695  cpu_tuple_cost * subpath->rows;
3696 
3697  return pathnode;
3698 }
3699 
3700 /*
3701  * create_modifytable_path
3702  * Creates a pathnode that represents performing INSERT/UPDATE/DELETE/MERGE
3703  * mods
3704  *
3705  * 'rel' is the parent relation associated with the result
3706  * 'subpath' is a Path producing source data
3707  * 'operation' is the operation type
3708  * 'canSetTag' is true if we set the command tag/es_processed
3709  * 'nominalRelation' is the parent RT index for use of EXPLAIN
3710  * 'rootRelation' is the partitioned/inherited table root RTI, or 0 if none
3711  * 'partColsUpdated' is true if any partitioning columns are being updated,
3712  * either from the target relation or a descendent partitioned table.
3713  * 'resultRelations' is an integer list of actual RT indexes of target rel(s)
3714  * 'updateColnosLists' is a list of UPDATE target column number lists
3715  * (one sublist per rel); or NIL if not an UPDATE
3716  * 'withCheckOptionLists' is a list of WCO lists (one per rel)
3717  * 'returningLists' is a list of RETURNING tlists (one per rel)
3718  * 'rowMarks' is a list of PlanRowMarks (non-locking only)
3719  * 'onconflict' is the ON CONFLICT clause, or NULL
3720  * 'epqParam' is the ID of Param for EvalPlanQual re-eval
3721  * 'mergeActionLists' is a list of lists of MERGE actions (one per rel)
3722  * 'mergeJoinConditions' is a list of join conditions for MERGE (one per rel)
3723  */
3726  Path *subpath,
3727  CmdType operation, bool canSetTag,
3728  Index nominalRelation, Index rootRelation,
3729  bool partColsUpdated,
3730  List *resultRelations,
3731  List *updateColnosLists,
3732  List *withCheckOptionLists, List *returningLists,
3733  List *rowMarks, OnConflictExpr *onconflict,
3734  List *mergeActionLists, List *mergeJoinConditions,
3735  int epqParam)
3736 {
3738 
3739  Assert(operation == CMD_MERGE ||
3740  (operation == CMD_UPDATE ?
3741  list_length(resultRelations) == list_length(updateColnosLists) :
3742  updateColnosLists == NIL));
3743  Assert(withCheckOptionLists == NIL ||
3744  list_length(resultRelations) == list_length(withCheckOptionLists));
3745  Assert(returningLists == NIL ||
3746  list_length(resultRelations) == list_length(returningLists));
3747 
3748  pathnode->path.pathtype = T_ModifyTable;
3749  pathnode->path.parent = rel;
3750  /* pathtarget is not interesting, just make it minimally valid */
3751  pathnode->path.pathtarget = rel->reltarget;
3752  /* For now, assume we are above any joins, so no parameterization */
3753  pathnode->path.param_info = NULL;
3754  pathnode->path.parallel_aware = false;
3755  pathnode->path.parallel_safe = false;
3756  pathnode->path.parallel_workers = 0;
3757  pathnode->path.pathkeys = NIL;
3758 
3759  /*
3760  * Compute cost & rowcount as subpath cost & rowcount (if RETURNING)
3761  *
3762  * Currently, we don't charge anything extra for the actual table
3763  * modification work, nor for the WITH CHECK OPTIONS or RETURNING
3764  * expressions if any. It would only be window dressing, since
3765  * ModifyTable is always a top-level node and there is no way for the
3766  * costs to change any higher-level planning choices. But we might want
3767  * to make it look better sometime.
3768  */
3769  pathnode->path.startup_cost = subpath->startup_cost;
3770  pathnode->path.total_cost = subpath->total_cost;
3771  if (returningLists != NIL)
3772  {
3773  pathnode->path.rows = subpath->rows;
3774 
3775  /*
3776  * Set width to match the subpath output. XXX this is totally wrong:
3777  * we should return an average of the RETURNING tlist widths. But
3778  * it's what happened historically, and improving it is a task for
3779  * another day. (Again, it's mostly window dressing.)
3780  */
3781  pathnode->path.pathtarget->width = subpath->pathtarget->width;
3782  }
3783  else
3784  {
3785  pathnode->path.rows = 0;
3786  pathnode->path.pathtarget->width = 0;
3787  }
3788 
3789  pathnode->subpath = subpath;
3790  pathnode->operation = operation;
3791  pathnode->canSetTag = canSetTag;
3792  pathnode->nominalRelation = nominalRelation;
3793  pathnode->rootRelation = rootRelation;
3794  pathnode->partColsUpdated = partColsUpdated;
3795  pathnode->resultRelations = resultRelations;
3796  pathnode->updateColnosLists = updateColnosLists;
3797  pathnode->withCheckOptionLists = withCheckOptionLists;
3798  pathnode->returningLists = returningLists;
3799  pathnode->rowMarks = rowMarks;
3800  pathnode->onconflict = onconflict;
3801  pathnode->epqParam = epqParam;
3802  pathnode->mergeActionLists = mergeActionLists;
3803  pathnode->mergeJoinConditions = mergeJoinConditions;
3804 
3805  return pathnode;
3806 }
3807 
3808 /*
3809  * create_limit_path
3810  * Creates a pathnode that represents performing LIMIT/OFFSET
3811  *
3812  * In addition to providing the actual OFFSET and LIMIT expressions,
3813  * the caller must provide estimates of their values for costing purposes.
3814  * The estimates are as computed by preprocess_limit(), ie, 0 represents
3815  * the clause not being present, and -1 means it's present but we could
3816  * not estimate its value.
3817  *
3818  * 'rel' is the parent relation associated with the result
3819  * 'subpath' is the path representing the source of data
3820  * 'limitOffset' is the actual OFFSET expression, or NULL
3821  * 'limitCount' is the actual LIMIT expression, or NULL
3822  * 'offset_est' is the estimated value of the OFFSET expression
3823  * 'count_est' is the estimated value of the LIMIT expression
3824  */
3825 LimitPath *
3827  Path *subpath,
3828  Node *limitOffset, Node *limitCount,
3829  LimitOption limitOption,
3830  int64 offset_est, int64 count_est)
3831 {
3832  LimitPath *pathnode = makeNode(LimitPath);
3833 
3834  pathnode->path.pathtype = T_Limit;
3835  pathnode->path.parent = rel;
3836  /* Limit doesn't project, so use source path's pathtarget */
3837  pathnode->path.pathtarget = subpath->pathtarget;
3838  /* For now, assume we are above any joins, so no parameterization */
3839  pathnode->path.param_info = NULL;
3840  pathnode->path.parallel_aware = false;
3841  pathnode->path.parallel_safe = rel->consider_parallel &&
3842  subpath->parallel_safe;
3843  pathnode->path.parallel_workers = subpath->parallel_workers;
3844  pathnode->path.rows = subpath->rows;
3845  pathnode->path.startup_cost = subpath->startup_cost;
3846  pathnode->path.total_cost = subpath->total_cost;
3847  pathnode->path.pathkeys = subpath->pathkeys;
3848  pathnode->subpath = subpath;
3849  pathnode->limitOffset = limitOffset;
3850  pathnode->limitCount = limitCount;
3851  pathnode->limitOption = limitOption;
3852 
3853  /*
3854  * Adjust the output rows count and costs according to the offset/limit.
3855  */
3856  adjust_limit_rows_costs(&pathnode->path.rows,
3857  &pathnode->path.startup_cost,
3858  &pathnode->path.total_cost,
3859  offset_est, count_est);
3860 
3861  return pathnode;
3862 }
3863 
3864 /*
3865  * adjust_limit_rows_costs
3866  * Adjust the size and cost estimates for a LimitPath node according to the
3867  * offset/limit.
3868  *
3869  * This is only a cosmetic issue if we are at top level, but if we are
3870  * building a subquery then it's important to report correct info to the outer
3871  * planner.
3872  *
3873  * When the offset or count couldn't be estimated, use 10% of the estimated
3874  * number of rows emitted from the subpath.
3875  *
3876  * XXX we don't bother to add eval costs of the offset/limit expressions
3877  * themselves to the path costs. In theory we should, but in most cases those
3878  * expressions are trivial and it's just not worth the trouble.
3879  */
3880 void
3881 adjust_limit_rows_costs(double *rows, /* in/out parameter */
3882  Cost *startup_cost, /* in/out parameter */
3883  Cost *total_cost, /* in/out parameter */
3884  int64 offset_est,
3885  int64 count_est)
3886 {
3887  double input_rows = *rows;
3888  Cost input_startup_cost = *startup_cost;
3889  Cost input_total_cost = *total_cost;
3890 
3891  if (offset_est != 0)
3892  {
3893  double offset_rows;
3894 
3895  if (offset_est > 0)
3896  offset_rows = (double) offset_est;
3897  else
3898  offset_rows = clamp_row_est(input_rows * 0.10);
3899  if (offset_rows > *rows)
3900  offset_rows = *rows;
3901  if (input_rows > 0)
3902  *startup_cost +=
3903  (input_total_cost - input_startup_cost)
3904  * offset_rows / input_rows;
3905  *rows -= offset_rows;
3906  if (*rows < 1)
3907  *rows = 1;
3908  }
3909 
3910  if (count_est != 0)
3911  {
3912  double count_rows;
3913 
3914  if (count_est > 0)
3915  count_rows = (double) count_est;
3916  else
3917  count_rows = clamp_row_est(input_rows * 0.10);
3918  if (count_rows > *rows)
3919  count_rows = *rows;
3920  if (input_rows > 0)
3921  *total_cost = *startup_cost +
3922  (input_total_cost - input_startup_cost)
3923  * count_rows / input_rows;
3924  *rows = count_rows;
3925  if (*rows < 1)
3926  *rows = 1;
3927  }
3928 }
3929 
3930 
3931 /*
3932  * reparameterize_path
3933  * Attempt to modify a Path to have greater parameterization
3934  *
3935  * We use this to attempt to bring all child paths of an appendrel to the
3936  * same parameterization level, ensuring that they all enforce the same set
3937  * of join quals (and thus that that parameterization can be attributed to
3938  * an append path built from such paths). Currently, only a few path types
3939  * are supported here, though more could be added at need. We return NULL
3940  * if we can't reparameterize the given path.
3941  *
3942  * Note: we intentionally do not pass created paths to add_path(); it would
3943  * possibly try to delete them on the grounds of being cost-inferior to the
3944  * paths they were made from, and we don't want that. Paths made here are
3945  * not necessarily of general-purpose usefulness, but they can be useful
3946  * as members of an append path.
3947  */
3948 Path *
3950  Relids required_outer,
3951  double loop_count)
3952 {
3953  RelOptInfo *rel = path->parent;
3954 
3955  /* Can only increase, not decrease, path's parameterization */
3956  if (!bms_is_subset(PATH_REQ_OUTER(path), required_outer))
3957  return NULL;
3958  switch (path->pathtype)
3959  {
3960  case T_SeqScan:
3961  return create_seqscan_path(root, rel, required_outer, 0);
3962  case T_SampleScan:
3963  return (Path *) create_samplescan_path(root, rel, required_outer);
3964  case T_IndexScan:
3965  case T_IndexOnlyScan:
3966  {
3967  IndexPath *ipath = (IndexPath *) path;
3968  IndexPath *newpath = makeNode(IndexPath);
3969 
3970  /*
3971  * We can't use create_index_path directly, and would not want
3972  * to because it would re-compute the indexqual conditions
3973  * which is wasted effort. Instead we hack things a bit:
3974  * flat-copy the path node, revise its param_info, and redo
3975  * the cost estimate.
3976  */
3977  memcpy(newpath, ipath, sizeof(IndexPath));
3978  newpath->path.param_info =
3979  get_baserel_parampathinfo(root, rel, required_outer);
3980  cost_index(newpath, root, loop_count, false);
3981  return (Path *) newpath;
3982  }
3983  case T_BitmapHeapScan:
3984  {
3985  BitmapHeapPath *bpath = (BitmapHeapPath *) path;
3986 
3987  return (Path *) create_bitmap_heap_path(root,
3988  rel,
3989  bpath->bitmapqual,
3990  required_outer,
3991  loop_count, 0);
3992  }
3993  case T_SubqueryScan:
3994  {
3995  SubqueryScanPath *spath = (SubqueryScanPath *) path;
3996  Path *subpath = spath->subpath;
3997  bool trivial_pathtarget;
3998 
3999  /*
4000  * If existing node has zero extra cost, we must have decided
4001  * its target is trivial. (The converse is not true, because
4002  * it might have a trivial target but quals to enforce; but in
4003  * that case the new node will too, so it doesn't matter
4004  * whether we get the right answer here.)
4005  */
4006  trivial_pathtarget =
4007  (subpath->total_cost == spath->path.total_cost);
4008 
4009  return (Path *) create_subqueryscan_path(root,
4010  rel,
4011  subpath,
4012  trivial_pathtarget,
4013  spath->path.pathkeys,
4014  required_outer);
4015  }
4016  case T_Result:
4017  /* Supported only for RTE_RESULT scan paths */
4018  if (IsA(path, Path))
4019  return create_resultscan_path(root, rel, required_outer);
4020  break;
4021  case T_Append:
4022  {
4023  AppendPath *apath = (AppendPath *) path;
4024  List *childpaths = NIL;
4025  List *partialpaths = NIL;
4026  int i;
4027  ListCell *lc;
4028 
4029  /* Reparameterize the children */
4030  i = 0;
4031  foreach(lc, apath->subpaths)
4032  {
4033  Path *spath = (Path *) lfirst(lc);
4034 
4035  spath = reparameterize_path(root, spath,
4036  required_outer,
4037  loop_count);
4038  if (spath == NULL)
4039  return NULL;
4040  /* We have to re-split the regular and partial paths */
4041  if (i < apath->first_partial_path)
4042  childpaths = lappend(childpaths, spath);
4043  else
4044  partialpaths = lappend(partialpaths, spath);
4045  i++;
4046  }
4047  return (Path *)
4048  create_append_path(root, rel, childpaths, partialpaths,
4049  apath->path.pathkeys, required_outer,
4050  apath->path.parallel_workers,
4051  apath->path.parallel_aware,
4052  -1);
4053  }
4054  case T_Material:
4055  {
4056  MaterialPath *mpath = (MaterialPath *) path;
4057  Path *spath = mpath->subpath;
4058 
4059  spath = reparameterize_path(root, spath,
4060  required_outer,
4061  loop_count);
4062  if (spath == NULL)
4063  return NULL;
4064  return (Path *) create_material_path(rel, spath);
4065  }
4066  case T_Memoize:
4067  {
4068  MemoizePath *mpath = (MemoizePath *) path;
4069  Path *spath = mpath->subpath;
4070 
4071  spath = reparameterize_path(root, spath,
4072  required_outer,
4073  loop_count);
4074  if (spath == NULL)
4075  return NULL;
4076  return (Path *) create_memoize_path(root, rel,
4077  spath,
4078  mpath->param_exprs,
4079  mpath->hash_operators,
4080  mpath->singlerow,
4081  mpath->binary_mode,
4082  mpath->calls);
4083  }
4084  default:
4085  break;
4086  }
4087  return NULL;
4088 }
4089 
4090 /*
4091  * reparameterize_path_by_child
4092  * Given a path parameterized by the parent of the given child relation,
4093  * translate the path to be parameterized by the given child relation.
4094  *
4095  * Most fields in the path are not changed, but any expressions must be
4096  * adjusted to refer to the correct varnos, and any subpaths must be
4097  * recursively reparameterized. Other fields that refer to specific relids
4098  * also need adjustment.
4099  *
4100  * The cost, number of rows, width and parallel path properties depend upon
4101  * path->parent, which does not change during the translation. So we need
4102  * not change those.
4103  *
4104  * Currently, only a few path types are supported here, though more could be
4105  * added at need. We return NULL if we can't reparameterize the given path.
4106  *
4107  * Note that this function can change referenced RangeTblEntries, RelOptInfos
4108  * and IndexOptInfos as well as the Path structures. Therefore, it's only safe
4109  * to call during create_plan(), when we have made a final choice of which Path
4110  * to use for each RangeTblEntry/RelOptInfo/IndexOptInfo.
4111  *
4112  * Keep this code in sync with path_is_reparameterizable_by_child()!
4113  */
4114 Path *
4116  RelOptInfo *child_rel)
4117 {
4118  Path *new_path;
4119  ParamPathInfo *new_ppi;
4120  ParamPathInfo *old_ppi;
4121  Relids required_outer;
4122 
4123 #define ADJUST_CHILD_ATTRS(node) \
4124  ((node) = (void *) adjust_appendrel_attrs_multilevel(root, \
4125  (Node *) (node), \
4126  child_rel, \
4127  child_rel->top_parent))
4128 
4129 #define REPARAMETERIZE_CHILD_PATH(path) \
4130 do { \
4131  (path) = reparameterize_path_by_child(root, (path), child_rel); \
4132  if ((path) == NULL) \
4133  return NULL; \
4134 } while(0)
4135 
4136 #define REPARAMETERIZE_CHILD_PATH_LIST(pathlist) \
4137 do { \
4138  if ((pathlist) != NIL) \
4139  { \
4140  (pathlist) = reparameterize_pathlist_by_child(root, (pathlist), \
4141  child_rel); \
4142  if ((pathlist) == NIL) \
4143  return NULL; \
4144  } \
4145 } while(0)
4146 
4147  /*
4148  * If the path is not parameterized by the parent of the given relation,
4149  * it doesn't need reparameterization.
4150  */
4151  if (!path->param_info ||
4152  !bms_overlap(PATH_REQ_OUTER(path), child_rel->top_parent_relids))
4153  return path;
4154 
4155  /*
4156  * If possible, reparameterize the given path.
4157  *
4158  * This function is currently only applied to the inner side of a nestloop
4159  * join that is being partitioned by the partitionwise-join code. Hence,
4160  * we need only support path types that plausibly arise in that context.
4161  * (In particular, supporting sorted path types would be a waste of code
4162  * and cycles: even if we translated them here, they'd just lose in
4163  * subsequent cost comparisons.) If we do see an unsupported path type,
4164  * that just means we won't be able to generate a partitionwise-join plan
4165  * using that path type.
4166  */
4167  switch (nodeTag(path))
4168  {
4169  case T_Path:
4170  new_path = path;
4171  ADJUST_CHILD_ATTRS(new_path->parent->baserestrictinfo);
4172  if (path->pathtype == T_SampleScan)
4173  {
4174  Index scan_relid = path->parent->relid;
4175  RangeTblEntry *rte;
4176 
4177  /* it should be a base rel with a tablesample clause... */
4178  Assert(scan_relid > 0);
4179  rte = planner_rt_fetch(scan_relid, root);
4180  Assert(rte->rtekind == RTE_RELATION);
4181  Assert(rte->tablesample != NULL);
4182 
4184  }
4185  break;
4186 
4187  case T_IndexPath:
4188  {
4189  IndexPath *ipath = (IndexPath *) path;
4190 
4193  new_path = (Path *) ipath;
4194  }
4195  break;
4196 
4197  case T_BitmapHeapPath:
4198  {
4199  BitmapHeapPath *bhpath = (BitmapHeapPath *) path;
4200 
4201  ADJUST_CHILD_ATTRS(bhpath->path.parent->baserestrictinfo);
4203  new_path = (Path *) bhpath;
4204  }
4205  break;
4206 
4207  case T_BitmapAndPath:
4208  {
4209  BitmapAndPath *bapath = (BitmapAndPath *) path;
4210 
4212  new_path = (Path *) bapath;
4213  }
4214  break;
4215 
4216  case T_BitmapOrPath:
4217  {
4218  BitmapOrPath *bopath = (BitmapOrPath *) path;
4219 
4221  new_path = (Path *) bopath;
4222  }
4223  break;
4224 
4225  case T_ForeignPath:
4226  {
4227  ForeignPath *fpath = (ForeignPath *) path;
4229 
4230  ADJUST_CHILD_ATTRS(fpath->path.parent->baserestrictinfo);
4231  if (fpath->fdw_outerpath)
4233  if (fpath->fdw_restrictinfo)
4235 
4236  /* Hand over to FDW if needed. */
4237  rfpc_func =
4238  path->parent->fdwroutine->ReparameterizeForeignPathByChild;
4239  if (rfpc_func)
4240  fpath->fdw_private = rfpc_func(root, fpath->fdw_private,
4241  child_rel);
4242  new_path = (Path *) fpath;
4243  }
4244  break;
4245 
4246  case T_CustomPath:
4247  {
4248  CustomPath *cpath = (CustomPath *) path;
4249 
4250  ADJUST_CHILD_ATTRS(cpath->path.parent->baserestrictinfo);
4252  if (cpath->custom_restrictinfo)
4254  if (cpath->methods &&
4256  cpath->custom_private =
4258  cpath->custom_private,
4259  child_rel);
4260  new_path = (Path *) cpath;
4261  }
4262  break;
4263 
4264  case T_NestPath:
4265  {
4266  NestPath *npath = (NestPath *) path;
4267  JoinPath *jpath = (JoinPath *) npath;
4268 
4272  new_path = (Path *) npath;
4273  }
4274  break;
4275 
4276  case T_MergePath:
4277  {
4278  MergePath *mpath = (MergePath *) path;
4279  JoinPath *jpath = (JoinPath *) mpath;
4280 
4285  new_path = (Path *) mpath;
4286  }
4287  break;
4288 
4289  case T_HashPath:
4290  {
4291  HashPath *hpath = (HashPath *) path;
4292  JoinPath *jpath = (JoinPath *) hpath;
4293 
4298  new_path = (Path *) hpath;
4299  }
4300  break;
4301 
4302  case T_AppendPath:
4303  {
4304  AppendPath *apath = (AppendPath *) path;
4305 
4307  new_path = (Path *) apath;
4308  }
4309  break;
4310 
4311  case T_MaterialPath:
4312  {
4313  MaterialPath *mpath = (MaterialPath *) path;
4314 
4316  new_path = (Path *) mpath;
4317  }
4318  break;
4319 
4320  case T_MemoizePath:
4321  {
4322  MemoizePath *mpath = (MemoizePath *) path;
4323 
4326  new_path = (Path *) mpath;
4327  }
4328  break;
4329 
4330  case T_GatherPath:
4331  {
4332  GatherPath *gpath = (GatherPath *) path;
4333 
4335  new_path = (Path *) gpath;
4336  }
4337  break;
4338 
4339  default:
4340  /* We don't know how to reparameterize this path. */
4341  return NULL;
4342  }
4343 
4344  /*
4345  * Adjust the parameterization information, which refers to the topmost
4346  * parent. The topmost parent can be multiple levels away from the given
4347  * child, hence use multi-level expression adjustment routines.
4348  */
4349  old_ppi = new_path->param_info;
4350  required_outer =
4352  child_rel,
4353  child_rel->top_parent);
4354 
4355  /* If we already have a PPI for this parameterization, just return it */
4356  new_ppi = find_param_path_info(new_path->parent, required_outer);
4357 
4358  /*
4359  * If not, build a new one and link it to the list of PPIs. For the same
4360  * reason as explained in mark_dummy_rel(), allocate new PPI in the same
4361  * context the given RelOptInfo is in.
4362  */
4363  if (new_ppi == NULL)
4364  {
4365  MemoryContext oldcontext;
4366  RelOptInfo *rel = path->parent;
4367 
4368  oldcontext = MemoryContextSwitchTo(GetMemoryChunkContext(rel));
4369 
4370  new_ppi = makeNode(ParamPathInfo);
4371  new_ppi->ppi_req_outer = bms_copy(required_outer);
4372  new_ppi->ppi_rows = old_ppi->ppi_rows;
4373  new_ppi->ppi_clauses = old_ppi->ppi_clauses;
4374  ADJUST_CHILD_ATTRS(new_ppi->ppi_clauses);
4375  new_ppi->ppi_serials = bms_copy(old_ppi->ppi_serials);
4376  rel->ppilist = lappend(rel->ppilist, new_ppi);
4377 
4378  MemoryContextSwitchTo(oldcontext);
4379  }
4380  bms_free(required_outer);
4381 
4382  new_path->param_info = new_ppi;
4383 
4384  /*
4385  * Adjust the path target if the parent of the outer relation is
4386  * referenced in the targetlist. This can happen when only the parent of
4387  * outer relation is laterally referenced in this relation.
4388  */
4389  if (bms_overlap(path->parent->lateral_relids,
4390  child_rel->top_parent_relids))
4391  {
4392  new_path->pathtarget = copy_pathtarget(new_path->pathtarget);
4393  ADJUST_CHILD_ATTRS(new_path->pathtarget->exprs);
4394  }
4395 
4396  return new_path;
4397 }
4398 
4399 /*
4400  * path_is_reparameterizable_by_child
4401  * Given a path parameterized by the parent of the given child relation,
4402  * see if it can be translated to be parameterized by the child relation.
4403  *
4404  * This must return true if and only if reparameterize_path_by_child()
4405  * would succeed on this path. Currently it's sufficient to verify that
4406  * the path and all of its subpaths (if any) are of the types handled by
4407  * that function. However, subpaths that are not parameterized can be
4408  * disregarded since they won't require translation.
4409  */
4410 bool
4412 {
4413 #define REJECT_IF_PATH_NOT_REPARAMETERIZABLE(path) \
4414 do { \
4415  if (!path_is_reparameterizable_by_child(path, child_rel)) \
4416  return false; \
4417 } while(0)
4418 
4419 #define REJECT_IF_PATH_LIST_NOT_REPARAMETERIZABLE(pathlist) \
4420 do { \
4421  if (!pathlist_is_reparameterizable_by_child(pathlist, child_rel)) \
4422  return false; \
4423 } while(0)
4424 
4425  /*
4426  * If the path is not parameterized by the parent of the given relation,
4427  * it doesn't need reparameterization.
4428  */
4429  if (!path->param_info ||
4430  !bms_overlap(PATH_REQ_OUTER(path), child_rel->top_parent_relids))
4431  return true;
4432 
4433  /*
4434  * Check that the path type is one that reparameterize_path_by_child() can
4435  * handle, and recursively check subpaths.
4436  */
4437  switch (nodeTag(path))
4438  {
4439  case T_Path:
4440  case T_IndexPath:
4441  break;
4442 
4443  case T_BitmapHeapPath:
4444  {
4445  BitmapHeapPath *bhpath = (BitmapHeapPath *) path;
4446 
4448  }
4449  break;
4450 
4451  case T_BitmapAndPath:
4452  {
4453  BitmapAndPath *bapath = (BitmapAndPath *) path;
4454 
4456  }
4457  break;
4458 
4459  case T_BitmapOrPath:
4460  {
4461  BitmapOrPath *bopath = (BitmapOrPath *) path;
4462 
4464  }
4465  break;
4466 
4467  case T_ForeignPath:
4468  {
4469  ForeignPath *fpath = (ForeignPath *) path;
4470 
4471  if (fpath->fdw_outerpath)
4473  }
4474  break;
4475 
4476  case T_CustomPath:
4477  {
4478  CustomPath *cpath = (CustomPath *) path;
4479 
4481  }
4482  break;
4483 
4484  case T_NestPath:
4485  case T_MergePath:
4486  case T_HashPath:
4487  {
4488  JoinPath *jpath = (JoinPath *) path;
4489 
4492  }
4493  break;
4494 
4495  case T_AppendPath:
4496  {
4497  AppendPath *apath = (AppendPath *) path;
4498 
4500  }
4501  break;
4502 
4503  case T_MaterialPath:
4504  {
4505  MaterialPath *mpath = (MaterialPath *) path;
4506 
4508  }
4509  break;
4510 
4511  case T_MemoizePath:
4512  {
4513  MemoizePath *mpath = (MemoizePath *) path;
4514 
4516  }
4517  break;
4518 
4519  case T_GatherPath:
4520  {
4521  GatherPath *gpath = (GatherPath *) path;
4522 
4524  }
4525  break;
4526 
4527  default:
4528  /* We don't know how to reparameterize this path. */
4529  return false;
4530  }
4531 
4532  return true;
4533 }
4534 
4535 /*
4536  * reparameterize_pathlist_by_child
4537  * Helper function to reparameterize a list of paths by given child rel.
4538  *
4539  * Returns NIL to indicate failure, so pathlist had better not be NIL.
4540  */
4541 static List *
4543  List *pathlist,
4544  RelOptInfo *child_rel)
4545 {
4546  ListCell *lc;
4547  List *result = NIL;
4548 
4549  foreach(lc, pathlist)
4550  {
4552  child_rel);
4553 
4554  if (path == NULL)
4555  {
4556  list_free(result);
4557  return NIL;
4558  }
4559 
4560  result = lappend(result, path);
4561  }
4562 
4563  return result;
4564 }
4565 
4566 /*
4567  * pathlist_is_reparameterizable_by_child
4568  * Helper function to check if a list of paths can be reparameterized.
4569  */
4570 static bool
4572 {
4573  ListCell *lc;
4574 
4575  foreach(lc, pathlist)
4576  {
4577  Path *path = (Path *) lfirst(lc);
4578 
4579  if (!path_is_reparameterizable_by_child(path, child_rel))
4580  return false;
4581  }
4582 
4583  return true;
4584 }
Datum sort(PG_FUNCTION_ARGS)
Definition: _int_op.c:195
bool query_is_distinct_for(Query *query, List *colnos, List *opids)
Definition: analyzejoins.c:995
bool query_supports_distinctness(Query *query)
Definition: analyzejoins.c:958
Relids adjust_child_relids_multilevel(PlannerInfo *root, Relids relids, RelOptInfo *childrel, RelOptInfo *parentrel)
Definition: appendinfo.c:588
int16 AttrNumber
Definition: attnum.h:21
bool bms_equal(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:142
BMS_Comparison bms_subset_compare(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:445
bool bms_is_subset(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:412
void bms_free(Bitmapset *a)
Definition: bitmapset.c:239
bool bms_is_member(int x, const Bitmapset *a)
Definition: bitmapset.c:510
Bitmapset * bms_union(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:251
Bitmapset * bms_add_members(Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:917
Bitmapset * bms_del_members(Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:1161
bool bms_overlap(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:582
int bms_compare(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:183
Bitmapset * bms_copy(const Bitmapset *a)
Definition: bitmapset.c:122
#define bms_is_empty(a)
Definition: bitmapset.h:118
BMS_Comparison
Definition: bitmapset.h:61
@ BMS_DIFFERENT
Definition: bitmapset.h:65
@ BMS_SUBSET1
Definition: bitmapset.h:63
@ BMS_EQUAL
Definition: bitmapset.h:62
@ BMS_SUBSET2
Definition: bitmapset.h:64
#define PG_USED_FOR_ASSERTS_ONLY
Definition: c.h:182
#define Assert(condition)
Definition: c.h:858
unsigned int Index
Definition: c.h:614
bool is_parallel_safe(PlannerInfo *root, Node *node)
Definition: clauses.c:753
double expression_returns_set_rows(PlannerInfo *root, Node *clause)
Definition: clauses.c:289
double cpu_operator_cost
Definition: costsize.c:123
void final_cost_hashjoin(PlannerInfo *root, HashPath *path, JoinCostWorkspace *workspace, JoinPathExtraData *extra)
Definition: costsize.c:4181
void final_cost_mergejoin(PlannerInfo *root, MergePath *path, JoinCostWorkspace *workspace, JoinPathExtraData *extra)
Definition: costsize.c:3745
void cost_functionscan(Path *path, PlannerInfo *root, RelOptInfo *baserel, ParamPathInfo *param_info)
Definition: costsize.c:1531
void cost_material(Path *path, Cost input_startup_cost, Cost input_total_cost, double tuples, int width)
Definition: costsize.c:2453
void cost_bitmap_heap_scan(Path *path, PlannerInfo *root, RelOptInfo *baserel, ParamPathInfo *param_info, Path *bitmapqual, double loop_count)
Definition: costsize.c:1013
void cost_tidrangescan(Path *path, PlannerInfo *root, RelOptInfo *baserel, List *tidrangequals, ParamPathInfo *param_info)
Definition: costsize.c:1357
void cost_merge_append(Path *path, PlannerInfo *root, List *pathkeys, int n_streams, Cost input_startup_cost, Cost input_total_cost, double tuples)
Definition: costsize.c:2404
void final_cost_nestloop(PlannerInfo *root, NestPath *path, JoinCostWorkspace *workspace, JoinPathExtraData *extra)
Definition: costsize.c:3308
void cost_recursive_union(Path *runion, Path *nrterm, Path *rterm)
Definition: costsize.c:1813
void cost_incremental_sort(Path *path, PlannerInfo *root, List *pathkeys, int presorted_keys, Cost input_startup_cost, Cost input_total_cost, double input_tuples, int width, Cost comparison_cost, int sort_mem, double limit_tuples)
Definition: costsize.c:1986
void cost_tablefuncscan(Path *path, PlannerInfo *root, RelOptInfo *baserel, ParamPathInfo *param_info)
Definition: costsize.c:1592
double cpu_tuple_cost
Definition: costsize.c:121
void cost_samplescan(Path *path, PlannerInfo *root, RelOptInfo *baserel, ParamPathInfo *param_info)
Definition: costsize.c:361
void cost_gather(GatherPath *path, PlannerInfo *root, RelOptInfo *rel, ParamPathInfo *param_info, double *rows)
Definition: costsize.c:436
void cost_agg(Path *path, PlannerInfo *root, AggStrategy aggstrategy, const AggClauseCosts *aggcosts, int numGroupCols, double numGroups, List *quals, Cost input_startup_cost, Cost input_total_cost, double input_tuples, double input_width)
Definition: costsize.c:2650
void cost_namedtuplestorescan(Path *path, PlannerInfo *root, RelOptInfo *baserel, ParamPathInfo *param_info)
Definition: costsize.c:1739
void cost_seqscan(Path *path, PlannerInfo *root, RelOptInfo *baserel, ParamPathInfo *param_info)
Definition: costsize.c:284
void cost_valuesscan(Path *path, PlannerInfo *root, RelOptInfo *baserel, ParamPathInfo *param_info)
Definition: costsize.c:1648
void cost_qual_eval(QualCost *cost, List *quals, PlannerInfo *root)
Definition: costsize.c:4640
void cost_resultscan(Path *path, PlannerInfo *root, RelOptInfo *baserel, ParamPathInfo *param_info)
Definition: costsize.c:1776
void cost_windowagg(Path *path, PlannerInfo *root, List *windowFuncs, WindowClause *winclause, Cost input_startup_cost, Cost input_total_cost, double input_tuples)
Definition: costsize.c:3068
void cost_bitmap_and_node(BitmapAndPath *path, PlannerInfo *root)
Definition: costsize.c:1157
void cost_gather_merge(GatherMergePath *path, PlannerInfo *root, RelOptInfo *rel, ParamPathInfo *param_info, Cost input_startup_cost, Cost input_total_cost, double *rows)
Definition: costsize.c:474
void cost_tidscan(Path *path, PlannerInfo *root, RelOptInfo *baserel, List *tidquals, ParamPathInfo *param_info)
Definition: costsize.c:1249
double clamp_row_est(double nrows)
Definition: costsize.c:202
void cost_subqueryscan(SubqueryScanPath *path, PlannerInfo *root, RelOptInfo *baserel, ParamPathInfo *param_info, bool trivial_pathtarget)
Definition: costsize.c:1451
void cost_append(AppendPath *apath)
Definition: costsize.c:2231
void cost_ctescan(Path *path, PlannerInfo *root, RelOptInfo *baserel, ParamPathInfo *param_info)
Definition: costsize.c:1698
void cost_bitmap_or_node(BitmapOrPath *path, PlannerInfo *root)
Definition: costsize.c:1201
void cost_index(IndexPath *path, PlannerInfo *root, double loop_count, bool partial_path)
Definition: costsize.c:549
void cost_sort(Path *path, PlannerInfo *root, List *pathkeys, Cost input_cost, double tuples, int width, Cost comparison_cost, int sort_mem, double limit_tuples)
Definition: costsize.c:2124
void cost_group(Path *path, PlannerInfo *root, int numGroupCols, double numGroups, List *quals, Cost input_startup_cost, Cost input_total_cost, double input_tuples)
Definition: costsize.c:3163
bool is_projection_capable_path(Path *path)
Definition: createplan.c:7207
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:224
bool equal(const void *a, const void *b)
Definition: equalfuncs.c:223
List *(* ReparameterizeForeignPathByChild_function)(PlannerInfo *root, List *fdw_private, RelOptInfo *child_rel)
Definition: fdwapi.h:182
int work_mem
Definition: globals.c:128
bool relation_has_unique_index_for(PlannerInfo *root, RelOptInfo *rel, List *restrictlist, List *exprlist, List *oprlist)
Definition: indxpath.c:3440
int b
Definition: isn.c:70
int a
Definition: isn.c:69
int i
Definition: isn.c:73
if(TABLE==NULL||TABLE_index==NULL)
Definition: isn.c:77
void list_sort(List *list, list_sort_comparator cmp)
Definition: list.c:1674
List * list_insert_nth(List *list, int pos, void *datum)
Definition: list.c:439
List * lappend(List *list, void *datum)
Definition: list.c:339
List * list_copy_head(const List *oldlist, int len)
Definition: list.c:1593
List * lappend_int(List *list, int datum)
Definition: list.c:357
void list_free(List *list)
Definition: list.c:1546
List * list_concat(List *list1, const List *list2)
Definition: list.c:561
List * lcons(void *datum, List *list)
Definition: list.c:495
Datum subpath(PG_FUNCTION_ARGS)
Definition: ltree_op.c:310
void pfree(void *pointer)
Definition: mcxt.c:1520
MemoryContext GetMemoryChunkContext(void *pointer)
Definition: mcxt.c:707
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:122
size_t get_hash_memory_limit(void)
Definition: nodeHash.c:3595
SetOpCmd
Definition: nodes.h:396
SetOpStrategy
Definition: nodes.h:404
@ SETOP_SORTED
Definition: nodes.h:405
#define IsA(nodeptr, _type_)
Definition: nodes.h:158
#define copyObject(obj)
Definition: nodes.h:224
double Cost
Definition: nodes.h:251
#define nodeTag(nodeptr)
Definition: nodes.h:133
CmdType
Definition: nodes.h:263
@ CMD_MERGE
Definition: nodes.h:269
@ CMD_UPDATE
Definition: nodes.h:266
AggStrategy
Definition: nodes.h:352
@ AGG_SORTED
Definition: nodes.h:354
@ AGG_HASHED
Definition: nodes.h:355
@ AGG_MIXED
Definition: nodes.h:356
@ AGG_PLAIN
Definition: nodes.h:353
AggSplit
Definition: nodes.h:374
LimitOption
Definition: nodes.h:429
#define makeNode(_type_)
Definition: nodes.h:155
JoinType
Definition: nodes.h:288
@ JOIN_SEMI
Definition: nodes.h:307
@ RTE_SUBQUERY
Definition: parsenodes.h:1029
@ RTE_RELATION
Definition: parsenodes.h:1028
bool pathkeys_contained_in(List *keys1, List *keys2)
Definition: pathkeys.c:341
PathKeysComparison compare_pathkeys(List *keys1, List *keys2)
Definition: pathkeys.c:302
#define REPARAMETERIZE_CHILD_PATH_LIST(pathlist)
AppendPath * create_append_path(PlannerInfo *root, RelOptInfo *rel, List *subpaths, List *partial_subpaths, List *pathkeys, Relids required_outer, int parallel_workers, bool parallel_aware, double rows)
Definition: pathnode.c:1244
static int append_startup_cost_compare(const ListCell *a, const ListCell *b)
Definition: pathnode.c:1397
SortPath * create_sort_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, List *pathkeys, double limit_tuples)
Definition: pathnode.c:3000
TidPath * create_tidscan_path(PlannerInfo *root, RelOptInfo *rel, List *tidquals, Relids required_outer)
Definition: pathnode.c:1179
#define REPARAMETERIZE_CHILD_PATH(path)
GroupResultPath * create_group_result_path(PlannerInfo *root, RelOptInfo *rel, PathTarget *target, List *havingqual)
Definition: pathnode.c:1518
NestPath * create_nestloop_path(PlannerInfo *root, RelOptInfo *joinrel, JoinType jointype, JoinCostWorkspace *workspace, JoinPathExtraData *extra, Path *outer_path, Path *inner_path, List *restrict_clauses, List *pathkeys, Relids required_outer)
Definition: pathnode.c:2457
Relids calc_non_nestloop_required_outer(Path *outer_path, Path *inner_path)
Definition: pathnode.c:2405
UniquePath * create_unique_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, SpecialJoinInfo *sjinfo)
Definition: pathnode.c:1654
static PathCostComparison compare_path_costs_fuzzily(Path *path1, Path *path2, double fuzz_factor)
Definition: pathnode.c:164
bool path_is_reparameterizable_by_child(Path *path, RelOptInfo *child_rel)
Definition: pathnode.c:4411
IndexPath * create_index_path(PlannerInfo *root, IndexOptInfo *index, List *indexclauses, List *indexorderbys, List *indexorderbycols, List *pathkeys, ScanDirection indexscandir, bool indexonly, Relids required_outer, double loop_count, bool partial_path)
Definition: pathnode.c:993
LimitPath * create_limit_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, Node *limitOffset, Node *limitCount, LimitOption limitOption, int64 offset_est, int64 count_est)
Definition: pathnode.c:3826
ProjectionPath * create_projection_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, PathTarget *target)
Definition: pathnode.c:2685
GatherMergePath * create_gather_merge_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, PathTarget *target, List *pathkeys, Relids required_outer, double *rows)
Definition: pathnode.c:1881
UpperUniquePath * create_upper_unique_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, int numCols, double numGroups)
Definition: pathnode.c:3103
static bool pathlist_is_reparameterizable_by_child(List *pathlist, RelOptInfo *child_rel)
Definition: pathnode.c:4571
#define STD_FUZZ_FACTOR
Definition: pathnode.c:47
Relids calc_nestloop_required_outer(Relids outerrelids, Relids outer_paramrels, Relids innerrelids, Relids inner_paramrels)
Definition: pathnode.c:2378
Path * create_tablefuncscan_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer)
Definition: pathnode.c:2072
Path * create_namedtuplestorescan_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer)
Definition: pathnode.c:2150
#define REJECT_IF_PATH_LIST_NOT_REPARAMETERIZABLE(pathlist)
LockRowsPath * create_lockrows_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, List *rowMarks, int epqParam)
Definition: pathnode.c:3662
Path * reparameterize_path_by_child(PlannerInfo *root, Path *path, RelOptInfo *child_rel)
Definition: pathnode.c:4115
MergePath * create_mergejoin_path(PlannerInfo *root, RelOptInfo *joinrel, JoinType jointype, JoinCostWorkspace *workspace, JoinPathExtraData *extra, Path *outer_path, Path *inner_path, List *restrict_clauses, List *pathkeys, Relids required_outer, List *mergeclauses, List *outersortkeys, List *innersortkeys)
Definition: pathnode.c:2553
static List * reparameterize_pathlist_by_child(PlannerInfo *root, List *pathlist, RelOptInfo *child_rel)
Definition: pathnode.c:4542
GatherPath * create_gather_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, PathTarget *target, Relids required_outer, double *rows)
Definition: pathnode.c:1972
Path * create_resultscan_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer)
Definition: pathnode.c:2176
Path * create_samplescan_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer)
Definition: pathnode.c:952
MemoizePath * create_memoize_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, List *param_exprs, List *hash_operators, bool singlerow, bool binary_mode, double calls)
Definition: pathnode.c:1598
MergeAppendPath * create_merge_append_path(PlannerInfo *root, RelOptInfo *rel, List *subpaths, List *pathkeys, Relids required_outer)
Definition: pathnode.c:1415
void set_cheapest(RelOptInfo *parent_rel)
Definition: pathnode.c:242
Path * reparameterize_path(PlannerInfo *root, Path *path, Relids required_outer, double loop_count)
Definition: pathnode.c:3949
ProjectSetPath * create_set_projection_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, PathTarget *target)
Definition: pathnode.c:2882
SubqueryScanPath * create_subqueryscan_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, bool trivial_pathtarget, List *pathkeys, Relids required_outer)
Definition: pathnode.c:2016
ForeignPath * create_foreignscan_path(PlannerInfo *root, RelOptInfo *rel, PathTarget *target, double rows, Cost startup_cost, Cost total_cost, List *pathkeys, Relids required_outer, Path *fdw_outerpath, List *fdw_restrictinfo, List *fdw_private)
Definition: pathnode.c:2235
ForeignPath * create_foreign_upper_path(PlannerInfo *root, RelOptInfo *rel, PathTarget *target, double rows, Cost startup_cost, Cost total_cost, List *pathkeys, Path *fdw_outerpath, List *fdw_restrictinfo, List *fdw_private)
Definition: pathnode.c:2333
void add_partial_path(RelOptInfo *parent_rel, Path *new_path)
Definition: pathnode.c:747
MaterialPath * create_material_path(RelOptInfo *rel, Path *subpath)
Definition: pathnode.c:1566
Path * create_functionscan_path(PlannerInfo *root, RelOptInfo *rel, List *pathkeys, Relids required_outer)
Definition: pathnode.c:2046
#define ADJUST_CHILD_ATTRS(node)
BitmapOrPath * create_bitmap_or_path(PlannerInfo *root, RelOptInfo *rel, List *bitmapquals)
Definition: pathnode.c:1127
int compare_fractional_path_costs(Path *path1, Path *path2, double fraction)
Definition: pathnode.c:115
GroupPath * create_group_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, List *groupClause, List *qual, double numGroups)
Definition: pathnode.c:3044
PathCostComparison
Definition: pathnode.c:35
@ COSTS_EQUAL
Definition: pathnode.c:36
@ COSTS_BETTER1
Definition: pathnode.c:37
@ COSTS_BETTER2
Definition: pathnode.c:38
@ COSTS_DIFFERENT
Definition: pathnode.c:39
HashPath * create_hashjoin_path(PlannerInfo *root, RelOptInfo *joinrel, JoinType jointype, JoinCostWorkspace *workspace, JoinPathExtraData *extra, Path *outer_path, Path *inner_path, bool parallel_hash, List *restrict_clauses, Relids required_outer, List *hashclauses)
Definition: pathnode.c:2619
bool add_partial_path_precheck(RelOptInfo *parent_rel, Cost total_cost, List *pathkeys)
Definition: pathnode.c:865
GroupingSetsPath * create_groupingsets_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, List *having_qual, AggStrategy aggstrategy, List *rollups, const AggClauseCosts *agg_costs)
Definition: pathnode.c:3237
SetOpPath * create_setop_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, SetOpCmd cmd, SetOpStrategy strategy, List *distinctList, AttrNumber flagColIdx, int firstFlag, double numGroups, double outputRows)
Definition: pathnode.c:3555
#define REJECT_IF_PATH_NOT_REPARAMETERIZABLE(path)
RecursiveUnionPath * create_recursiveunion_path(PlannerInfo *root, RelOptInfo *rel, Path *leftpath, Path *rightpath, PathTarget *target, List *distinctList, int wtParam, double numGroups)
Definition: pathnode.c:3617
IncrementalSortPath * create_incremental_sort_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, List *pathkeys, int presorted_keys, double limit_tuples)
Definition: pathnode.c:2951
MinMaxAggPath * create_minmaxagg_path(PlannerInfo *root, RelOptInfo *rel, PathTarget *target, List *mmaggregates, List *quals)
Definition: pathnode.c:3397
Path * create_worktablescan_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer)
Definition: pathnode.c:2202
#define CONSIDER_PATH_STARTUP_COST(p)
WindowAggPath * create_windowagg_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, PathTarget *target, List *windowFuncs, List *runCondition, WindowClause *winclause, List *qual, bool topwindow)
Definition: pathnode.c:3485
AggPath * create_agg_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, PathTarget *target, AggStrategy aggstrategy, AggSplit aggsplit, List *groupClause, List *qual, const AggClauseCosts *aggcosts, double numGroups)
Definition: pathnode.c:3155
void add_path(RelOptInfo *parent_rel, Path *new_path)
Definition: pathnode.c:420
ModifyTablePath * create_modifytable_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, CmdType operation, bool canSetTag, Index nominalRelation, Index rootRelation, bool partColsUpdated, List *resultRelations, List *updateColnosLists, List *withCheckOptionLists, List *returningLists, List *rowMarks, OnConflictExpr *onconflict, List *mergeActionLists, List *mergeJoinConditions, int epqParam)
Definition: pathnode.c:3725
Path * create_valuesscan_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer)
Definition: pathnode.c:2098
int compare_path_costs(Path *path1, Path *path2, CostSelector criterion)
Definition: pathnode.c:69
Path * apply_projection_to_path(PlannerInfo *root, RelOptInfo *rel, Path *path, PathTarget *target)
Definition: pathnode.c:2793
static int append_total_cost_compare(const ListCell *a, const ListCell *b)
Definition: pathnode.c:1375
BitmapAndPath * create_bitmap_and_path(PlannerInfo *root, RelOptInfo *rel, List *bitmapquals)
Definition: pathnode.c:1075
TidRangePath * create_tidrangescan_path(PlannerInfo *root, RelOptInfo *rel, List *tidrangequals, Relids required_outer)
Definition: pathnode.c:1208
Path * create_seqscan_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer, int parallel_workers)
Definition: pathnode.c:927
void adjust_limit_rows_costs(double *rows, Cost *startup_cost, Cost *total_cost, int64 offset_est, int64 count_est)
Definition: pathnode.c:3881
ForeignPath * create_foreign_join_path(PlannerInfo *root, RelOptInfo *rel, PathTarget *target, double rows, Cost startup_cost, Cost total_cost, List *pathkeys, Relids required_outer, Path *fdw_outerpath, List *fdw_restrictinfo, List *fdw_private)
Definition: pathnode.c:2281
static List * translate_sub_tlist(List *tlist, int relid)
Definition: pathnode.c:1946
Path * create_ctescan_path(PlannerInfo *root, RelOptInfo *rel, List *pathkeys, Relids required_outer)
Definition: pathnode.c:2124
bool add_path_precheck(RelOptInfo *parent_rel, Cost startup_cost, Cost total_cost, List *pathkeys, Relids required_outer)
Definition: pathnode.c:642
BitmapHeapPath * create_bitmap_heap_path(PlannerInfo *root, RelOptInfo *rel, Path *bitmapqual, Relids required_outer, double loop_count, int parallel_degree)
Definition: pathnode.c:1042
#define IS_SIMPLE_REL(rel)
Definition: pathnodes.h:829
@ UNIQUE_PATH_SORT
Definition: pathnodes.h:2011
@ UNIQUE_PATH_NOOP
Definition: pathnodes.h:2009
@ UNIQUE_PATH_HASH
Definition: pathnodes.h:2010
CostSelector
Definition: pathnodes.h:37
@ TOTAL_COST
Definition: pathnodes.h:38
@ STARTUP_COST
Definition: pathnodes.h:38
#define PATH_REQ_OUTER(path)
Definition: pathnodes.h:1658
#define planner_rt_fetch(rti, root)
Definition: pathnodes.h:560
@ RELOPT_BASEREL
Definition: pathnodes.h:817
PathKeysComparison
Definition: paths.h:201
@ PATHKEYS_BETTER2
Definition: paths.h:204
@ PATHKEYS_BETTER1
Definition: paths.h:203
@ PATHKEYS_DIFFERENT
Definition: paths.h:205
@ PATHKEYS_EQUAL
Definition: paths.h:202
#define lfirst(lc)
Definition: pg_list.h:172
static int list_length(const List *l)
Definition: pg_list.h:152
#define NIL
Definition: pg_list.h:68
#define foreach_current_index(var_or_cell)
Definition: pg_list.h:403
#define foreach_delete_current(lst, var_or_cell)
Definition: pg_list.h:391
#define linitial(l)
Definition: pg_list.h:178
MemoryContextSwitchTo(old_ctx)
tree ctl root
Definition: radixtree.h:1884
static int cmp(const chr *x, const chr *y, size_t len)
Definition: regc_locale.c:743
ParamPathInfo * get_baserel_parampathinfo(PlannerInfo *root, RelOptInfo *baserel, Relids required_outer)
Definition: relnode.c:1557
ParamPathInfo * get_appendrel_parampathinfo(RelOptInfo *appendrel, Relids required_outer)
Definition: relnode.c:1868
ParamPathInfo * get_joinrel_parampathinfo(PlannerInfo *root, RelOptInfo *joinrel, Path *outer_path, Path *inner_path, SpecialJoinInfo *sjinfo, Relids required_outer, List **restrict_clauses)
Definition: relnode.c:1671
ParamPathInfo * find_param_path_info(RelOptInfo *rel, Relids required_outer)
Definition: relnode.c:1901
Bitmapset * get_param_path_clause_serials(Path *path)
Definition: relnode.c:1922
ScanDirection
Definition: sdir.h:25
double estimate_num_groups(PlannerInfo *root, List *groupExprs, double input_rows, List **pgset, EstimationInfo *estinfo)
Definition: selfuncs.c:3416
Size transitionSpace
Definition: pathnodes.h:62
Path * subpath
Definition: pathnodes.h:2243
Cardinality numGroups
Definition: pathnodes.h:2246
AggSplit aggsplit
Definition: pathnodes.h:2245
List * groupClause
Definition: pathnodes.h:2248
uint64 transitionSpace
Definition: pathnodes.h:2247
AggStrategy aggstrategy
Definition: pathnodes.h:2244
Path path
Definition: pathnodes.h:2242
List * qual
Definition: pathnodes.h:2249
int first_partial_path
Definition: pathnodes.h:1923
Cardinality limit_tuples
Definition: pathnodes.h:1924
List * subpaths
Definition: pathnodes.h:1921
List * bitmapquals
Definition: pathnodes.h:1786
Path * bitmapqual
Definition: pathnodes.h:1774
List * bitmapquals
Definition: pathnodes.h:1799
struct List *(* ReparameterizeCustomPathByChild)(PlannerInfo *root, List *custom_private, RelOptInfo *child_rel)
Definition: extensible.h:103
const struct CustomPathMethods * methods
Definition: pathnodes.h:1900
List * custom_paths
Definition: pathnodes.h:1897
List * custom_private
Definition: pathnodes.h:1899
List * custom_restrictinfo
Definition: pathnodes.h:1898
Path * fdw_outerpath
Definition: pathnodes.h:1859
List * fdw_restrictinfo
Definition: pathnodes.h:1860
List * fdw_private
Definition: pathnodes.h:1861
bool single_copy
Definition: pathnodes.h:2032
Path * subpath
Definition: pathnodes.h:2031
int num_workers
Definition: pathnodes.h:2033
List * qual
Definition: pathnodes.h:2217
List * groupClause
Definition: pathnodes.h:2216
Path * subpath
Definition: pathnodes.h:2215
Path path
Definition: pathnodes.h:2214
uint64 transitionSpace
Definition: pathnodes.h:2289
AggStrategy aggstrategy
Definition: pathnodes.h:2286
List * path_hashclauses
Definition: pathnodes.h:2141
JoinPath jpath
Definition: pathnodes.h:2140
List * indrestrictinfo
Definition: pathnodes.h:1171
List * indexclauses
Definition: pathnodes.h:1700
ScanDirection indexscandir
Definition: pathnodes.h:1703
Path path
Definition: pathnodes.h:1698
List * indexorderbycols
Definition: pathnodes.h:1702
List * indexorderbys
Definition: pathnodes.h:1701
IndexOptInfo * indexinfo
Definition: pathnodes.h:1699
SpecialJoinInfo * sjinfo
Definition: pathnodes.h:3222
Path * outerjoinpath
Definition: pathnodes.h:2063
Path * innerjoinpath
Definition: pathnodes.h:2064
JoinType jointype
Definition: pathnodes.h:2058
bool inner_unique
Definition: pathnodes.h:2060
List * joinrestrictinfo
Definition: pathnodes.h:2066
Path path
Definition: pathnodes.h:2389
Path * subpath
Definition: pathnodes.h:2390
LimitOption limitOption
Definition: pathnodes.h:2393
Node * limitOffset
Definition: pathnodes.h:2391
Node * limitCount
Definition: pathnodes.h:2392
Definition: pg_list.h:54
Path * subpath
Definition: pathnodes.h:2350
List * rowMarks
Definition: pathnodes.h:2351
Path * subpath
Definition: pathnodes.h:1971
bool singlerow
Definition: pathnodes.h:1985
List * hash_operators
Definition: pathnodes.h:1983
uint32 est_entries
Definition: pathnodes.h:1990
bool binary_mode
Definition: pathnodes.h:1987
Cardinality calls
Definition: pathnodes.h:1989
Path * subpath
Definition: pathnodes.h:1982
List * param_exprs
Definition: pathnodes.h:1984
Cardinality limit_tuples
Definition: pathnodes.h:1946
List * outersortkeys
Definition: pathnodes.h:2123
List * innersortkeys
Definition: pathnodes.h:2124
JoinPath jpath
Definition: pathnodes.h:2121
List * path_mergeclauses
Definition: pathnodes.h:2122
List * quals
Definition: pathnodes.h:2299
List * mmaggregates
Definition: pathnodes.h:2298
bool partColsUpdated
Definition: pathnodes.h:2370
List * returningLists
Definition: pathnodes.h:2374
List * resultRelations
Definition: pathnodes.h:2371
List * withCheckOptionLists
Definition: pathnodes.h:2373
List * mergeJoinConditions
Definition: pathnodes.h:2380
List * updateColnosLists
Definition: pathnodes.h:2372
OnConflictExpr * onconflict
Definition: pathnodes.h:2376
CmdType operation
Definition: pathnodes.h:2366
Index rootRelation
Definition: pathnodes.h:2369
Index nominalRelation
Definition: pathnodes.h:2368
List * mergeActionLists
Definition: pathnodes.h:2378
JoinPath jpath
Definition: pathnodes.h:2081
Definition: nodes.h:129
Cardinality ppi_rows
Definition: pathnodes.h:1569
List * ppi_clauses
Definition: pathnodes.h:1570
Bitmapset * ppi_serials
Definition: pathnodes.h:1571
Relids ppi_req_outer
Definition: pathnodes.h:1568
List * exprs
Definition: pathnodes.h:1522
QualCost cost
Definition: pathnodes.h:1528
List * pathkeys
Definition: pathnodes.h:1654
NodeTag pathtype
Definition: pathnodes.h:1615
Cardinality rows
Definition: pathnodes.h:1649
Cost startup_cost
Definition: pathnodes.h:1650
int parallel_workers
Definition: pathnodes.h:1646
Cost total_cost
Definition: pathnodes.h:1651
bool parallel_aware
Definition: pathnodes.h:1642
bool parallel_safe
Definition: pathnodes.h:1644
Path * subpath
Definition: pathnodes.h:2175
Path * subpath
Definition: pathnodes.h:2163
Cost per_tuple
Definition: pathnodes.h:48
Cost startup
Definition: pathnodes.h:47
struct TableSampleClause * tablesample
Definition: parsenodes.h:1108
Query * subquery
Definition: parsenodes.h:1114
RTEKind rtekind
Definition: parsenodes.h:1057
Cardinality numGroups
Definition: pathnodes.h:2341
bool consider_param_startup
Definition: pathnodes.h:875
List * ppilist
Definition: pathnodes.h:889
Relids relids
Definition: pathnodes.h:861
struct PathTarget * reltarget
Definition: pathnodes.h:883
Index relid
Definition: pathnodes.h:908
bool consider_parallel
Definition: pathnodes.h:877
Relids top_parent_relids
Definition: pathnodes.h:999
Relids lateral_relids
Definition: pathnodes.h:903
List * cheapest_parameterized_paths
Definition: pathnodes.h:894
List * pathlist
Definition: pathnodes.h:888
RelOptKind reloptkind
Definition: pathnodes.h:855
struct Path * cheapest_unique_path
Definition: pathnodes.h:893
struct Path * cheapest_startup_path
Definition: pathnodes.h:891
struct Path * cheapest_total_path
Definition: pathnodes.h:892
bool consider_startup
Definition: pathnodes.h:873
List * partial_pathlist
Definition: pathnodes.h:890
Cardinality rows
Definition: pathnodes.h:867
RTEKind rtekind
Definition: pathnodes.h:912
int rinfo_serial
Definition: pathnodes.h:2625
Cardinality numGroups
Definition: pathnodes.h:2273
List * gsets
Definition: pathnodes.h:2271
bool is_hashed
Definition: pathnodes.h:2275
List * distinctList
Definition: pathnodes.h:2325
Cardinality numGroups
Definition: pathnodes.h:2328
int firstFlag
Definition: pathnodes.h:2327
Path * subpath
Definition: pathnodes.h:2322
SetOpCmd cmd
Definition: pathnodes.h:2323
Path path
Definition: pathnodes.h:2321
SetOpStrategy strategy
Definition: pathnodes.h:2324
AttrNumber flagColIdx
Definition: pathnodes.h:2326
Path path
Definition: pathnodes.h:2188
Path * subpath
Definition: pathnodes.h:2189
List * semi_rhs_exprs
Definition: pathnodes.h:2898
JoinType jointype
Definition: pathnodes.h:2887
Relids syn_righthand
Definition: pathnodes.h:2886
List * semi_operators
Definition: pathnodes.h:2897
List * tidquals
Definition: pathnodes.h:1813
Path path
Definition: pathnodes.h:1812
List * tidrangequals
Definition: pathnodes.h:1825
Path * subpath
Definition: pathnodes.h:2017
List * uniq_exprs
Definition: pathnodes.h:2020
UniquePathMethod umethod
Definition: pathnodes.h:2018
List * in_operators
Definition: pathnodes.h:2019
Definition: primnodes.h:248
AttrNumber varattno
Definition: primnodes.h:260
int varno
Definition: primnodes.h:255
List * runCondition
Definition: pathnodes.h:2311
Path * subpath
Definition: pathnodes.h:2308
WindowClause * winclause
Definition: pathnodes.h:2309
Definition: type.h:95
PathTarget * copy_pathtarget(PathTarget *src)
Definition: tlist.c:657