1 /*-------------------------------------------------------------------------
2 *
3 * createplan.c
4 * Routines to create the desired plan for processing a query.
5 * Planning is complete, we just need to convert the selected
6 * Path into a Plan.
7 *
8 * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
9 * Portions Copyright (c) 1994, Regents of the University of California
10 *
11 *
12 * IDENTIFICATION
13 * src/backend/optimizer/plan/createplan.c
14 *
15 *-------------------------------------------------------------------------
16 */
17 #include "postgres.h"
18
19 #include <limits.h>
20 #include <math.h>
21
22 #include "access/sysattr.h"
23 #include "catalog/pg_class.h"
24 #include "foreign/fdwapi.h"
25 #include "miscadmin.h"
26 #include "nodes/extensible.h"
27 #include "nodes/makefuncs.h"
28 #include "nodes/nodeFuncs.h"
29 #include "optimizer/clauses.h"
30 #include "optimizer/cost.h"
31 #include "optimizer/optimizer.h"
32 #include "optimizer/paramassign.h"
33 #include "optimizer/paths.h"
34 #include "optimizer/placeholder.h"
35 #include "optimizer/plancat.h"
36 #include "optimizer/planmain.h"
37 #include "optimizer/restrictinfo.h"
38 #include "optimizer/subselect.h"
39 #include "optimizer/tlist.h"
40 #include "parser/parse_clause.h"
41 #include "parser/parsetree.h"
42 #include "partitioning/partprune.h"
43 #include "utils/lsyscache.h"
44
45
46 /*
47 * Flag bits that can appear in the flags argument of create_plan_recurse().
48 * These can be OR-ed together.
49 *
50 * CP_EXACT_TLIST specifies that the generated plan node must return exactly
51 * the tlist specified by the path's pathtarget (this overrides both
52 * CP_SMALL_TLIST and CP_LABEL_TLIST, if those are set). Otherwise, the
53 * plan node is allowed to return just the Vars and PlaceHolderVars needed
54 * to evaluate the pathtarget.
55 *
56 * CP_SMALL_TLIST specifies that a narrower tlist is preferred. This is
57 * passed down by parent nodes such as Sort and Hash, which will have to
58 * store the returned tuples.
59 *
60 * CP_LABEL_TLIST specifies that the plan node must return columns matching
61 * any sortgrouprefs specified in its pathtarget, with appropriate
62 * ressortgroupref labels. This is passed down by parent nodes such as Sort
63 * and Group, which need these values to be available in their inputs.
64 *
65 * CP_IGNORE_TLIST specifies that the caller plans to replace the targetlist,
66 * and therefore it doesn't matter a bit what target list gets generated.
67 */
68 #define CP_EXACT_TLIST 0x0001 /* Plan must return specified tlist */
69 #define CP_SMALL_TLIST 0x0002 /* Prefer narrower tlists */
70 #define CP_LABEL_TLIST 0x0004 /* tlist must contain sortgrouprefs */
71 #define CP_IGNORE_TLIST 0x0008 /* caller will replace tlist */
72
73
74 static Plan *create_plan_recurse(PlannerInfo *root, Path *best_path,
75 int flags);
76 static Plan *create_scan_plan(PlannerInfo *root, Path *best_path,
77 int flags);
78 static List *build_path_tlist(PlannerInfo *root, Path *path);
79 static bool use_physical_tlist(PlannerInfo *root, Path *path, int flags);
80 static List *get_gating_quals(PlannerInfo *root, List *quals);
81 static Plan *create_gating_plan(PlannerInfo *root, Path *path, Plan *plan,
82 List *gating_quals);
83 static Plan *create_join_plan(PlannerInfo *root, JoinPath *best_path);
84 static Plan *create_append_plan(PlannerInfo *root, AppendPath *best_path,
85 int flags);
86 static Plan *create_merge_append_plan(PlannerInfo *root, MergeAppendPath *best_path,
87 int flags);
88 static Result *create_group_result_plan(PlannerInfo *root,
89 GroupResultPath *best_path);
90 static ProjectSet *create_project_set_plan(PlannerInfo *root, ProjectSetPath *best_path);
91 static Material *create_material_plan(PlannerInfo *root, MaterialPath *best_path,
92 int flags);
93 static Plan *create_unique_plan(PlannerInfo *root, UniquePath *best_path,
94 int flags);
95 static Gather *create_gather_plan(PlannerInfo *root, GatherPath *best_path);
96 static Plan *create_projection_plan(PlannerInfo *root,
97 ProjectionPath *best_path,
98 int flags);
99 static Plan *inject_projection_plan(Plan *subplan, List *tlist, bool parallel_safe);
100 static Sort *create_sort_plan(PlannerInfo *root, SortPath *best_path, int flags);
101 static Group *create_group_plan(PlannerInfo *root, GroupPath *best_path);
102 static Unique *create_upper_unique_plan(PlannerInfo *root, UpperUniquePath *best_path,
103 int flags);
104 static Agg *create_agg_plan(PlannerInfo *root, AggPath *best_path);
105 static Plan *create_groupingsets_plan(PlannerInfo *root, GroupingSetsPath *best_path);
106 static Result *create_minmaxagg_plan(PlannerInfo *root, MinMaxAggPath *best_path);
107 static WindowAgg *create_windowagg_plan(PlannerInfo *root, WindowAggPath *best_path);
108 static SetOp *create_setop_plan(PlannerInfo *root, SetOpPath *best_path,
109 int flags);
110 static RecursiveUnion *create_recursiveunion_plan(PlannerInfo *root, RecursiveUnionPath *best_path);
111 static LockRows *create_lockrows_plan(PlannerInfo *root, LockRowsPath *best_path,
112 int flags);
113 static ModifyTable *create_modifytable_plan(PlannerInfo *root, ModifyTablePath *best_path);
114 static Limit *create_limit_plan(PlannerInfo *root, LimitPath *best_path,
115 int flags);
116 static SeqScan *create_seqscan_plan(PlannerInfo *root, Path *best_path,
117 List *tlist, List *scan_clauses);
118 static SampleScan *create_samplescan_plan(PlannerInfo *root, Path *best_path,
119 List *tlist, List *scan_clauses);
120 static Scan *create_indexscan_plan(PlannerInfo *root, IndexPath *best_path,
121 List *tlist, List *scan_clauses, bool indexonly);
122 static BitmapHeapScan *create_bitmap_scan_plan(PlannerInfo *root,
123 BitmapHeapPath *best_path,
124 List *tlist, List *scan_clauses);
125 static Plan *create_bitmap_subplan(PlannerInfo *root, Path *bitmapqual,
126 List **qual, List **indexqual, List **indexECs);
127 static void bitmap_subplan_mark_shared(Plan *plan);
128 static TidScan *create_tidscan_plan(PlannerInfo *root, TidPath *best_path,
129 List *tlist, List *scan_clauses);
130 static SubqueryScan *create_subqueryscan_plan(PlannerInfo *root,
131 SubqueryScanPath *best_path,
132 List *tlist, List *scan_clauses);
133 static FunctionScan *create_functionscan_plan(PlannerInfo *root, Path *best_path,
134 List *tlist, List *scan_clauses);
135 static ValuesScan *create_valuesscan_plan(PlannerInfo *root, Path *best_path,
136 List *tlist, List *scan_clauses);
137 static TableFuncScan *create_tablefuncscan_plan(PlannerInfo *root, Path *best_path,
138 List *tlist, List *scan_clauses);
139 static CteScan *create_ctescan_plan(PlannerInfo *root, Path *best_path,
140 List *tlist, List *scan_clauses);
141 static NamedTuplestoreScan *create_namedtuplestorescan_plan(PlannerInfo *root,
142 Path *best_path, List *tlist, List *scan_clauses);
143 static Result *create_resultscan_plan(PlannerInfo *root, Path *best_path,
144 List *tlist, List *scan_clauses);
145 static WorkTableScan *create_worktablescan_plan(PlannerInfo *root, Path *best_path,
146 List *tlist, List *scan_clauses);
147 static ForeignScan *create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path,
148 List *tlist, List *scan_clauses);
149 static CustomScan *create_customscan_plan(PlannerInfo *root,
150 CustomPath *best_path,
151 List *tlist, List *scan_clauses);
152 static NestLoop *create_nestloop_plan(PlannerInfo *root, NestPath *best_path);
153 static MergeJoin *create_mergejoin_plan(PlannerInfo *root, MergePath *best_path);
154 static HashJoin *create_hashjoin_plan(PlannerInfo *root, HashPath *best_path);
155 static Node *replace_nestloop_params(PlannerInfo *root, Node *expr);
156 static Node *replace_nestloop_params_mutator(Node *node, PlannerInfo *root);
157 static void fix_indexqual_references(PlannerInfo *root, IndexPath *index_path,
158 List **stripped_indexquals_p,
159 List **fixed_indexquals_p);
160 static List *fix_indexorderby_references(PlannerInfo *root, IndexPath *index_path);
161 static Node *fix_indexqual_clause(PlannerInfo *root,
162 IndexOptInfo *index, int indexcol,
163 Node *clause, List *indexcolnos);
164 static Node *fix_indexqual_operand(Node *node, IndexOptInfo *index, int indexcol);
165 static List *get_switched_clauses(List *clauses, Relids outerrelids);
166 static List *order_qual_clauses(PlannerInfo *root, List *clauses);
167 static void copy_generic_path_info(Plan *dest, Path *src);
168 static void copy_plan_costsize(Plan *dest, Plan *src);
169 static void label_sort_with_costsize(PlannerInfo *root, Sort *plan,
170 double limit_tuples);
171 static SeqScan *make_seqscan(List *qptlist, List *qpqual, Index scanrelid);
172 static SampleScan *make_samplescan(List *qptlist, List *qpqual, Index scanrelid,
173 TableSampleClause *tsc);
174 static IndexScan *make_indexscan(List *qptlist, List *qpqual, Index scanrelid,
175 Oid indexid, List *indexqual, List *indexqualorig,
176 List *indexorderby, List *indexorderbyorig,
177 List *indexorderbyops,
178 ScanDirection indexscandir);
179 static IndexOnlyScan *make_indexonlyscan(List *qptlist, List *qpqual,
180 Index scanrelid, Oid indexid,
181 List *indexqual, List *indexorderby,
182 List *indextlist,
183 ScanDirection indexscandir);
184 static BitmapIndexScan *make_bitmap_indexscan(Index scanrelid, Oid indexid,
185 List *indexqual,
186 List *indexqualorig);
187 static BitmapHeapScan *make_bitmap_heapscan(List *qptlist,
188 List *qpqual,
189 Plan *lefttree,
190 List *bitmapqualorig,
191 Index scanrelid);
192 static TidScan *make_tidscan(List *qptlist, List *qpqual, Index scanrelid,
193 List *tidquals);
194 static SubqueryScan *make_subqueryscan(List *qptlist,
195 List *qpqual,
196 Index scanrelid,
197 Plan *subplan);
198 static FunctionScan *make_functionscan(List *qptlist, List *qpqual,
199 Index scanrelid, List *functions, bool funcordinality);
200 static ValuesScan *make_valuesscan(List *qptlist, List *qpqual,
201 Index scanrelid, List *values_lists);
202 static TableFuncScan *make_tablefuncscan(List *qptlist, List *qpqual,
203 Index scanrelid, TableFunc *tablefunc);
204 static CteScan *make_ctescan(List *qptlist, List *qpqual,
205 Index scanrelid, int ctePlanId, int cteParam);
206 static NamedTuplestoreScan *make_namedtuplestorescan(List *qptlist, List *qpqual,
207 Index scanrelid, char *enrname);
208 static WorkTableScan *make_worktablescan(List *qptlist, List *qpqual,
209 Index scanrelid, int wtParam);
210 static RecursiveUnion *make_recursive_union(List *tlist,
211 Plan *lefttree,
212 Plan *righttree,
213 int wtParam,
214 List *distinctList,
215 long numGroups);
216 static BitmapAnd *make_bitmap_and(List *bitmapplans);
217 static BitmapOr *make_bitmap_or(List *bitmapplans);
218 static NestLoop *make_nestloop(List *tlist,
219 List *joinclauses, List *otherclauses, List *nestParams,
220 Plan *lefttree, Plan *righttree,
221 JoinType jointype, bool inner_unique);
222 static HashJoin *make_hashjoin(List *tlist,
223 List *joinclauses, List *otherclauses,
224 List *hashclauses,
225 List *hashoperators, List *hashcollations,
226 List *hashkeys,
227 Plan *lefttree, Plan *righttree,
228 JoinType jointype, bool inner_unique);
229 static Hash *make_hash(Plan *lefttree,
230 List *hashkeys,
231 Oid skewTable,
232 AttrNumber skewColumn,
233 bool skewInherit);
234 static MergeJoin *make_mergejoin(List *tlist,
235 List *joinclauses, List *otherclauses,
236 List *mergeclauses,
237 Oid *mergefamilies,
238 Oid *mergecollations,
239 int *mergestrategies,
240 bool *mergenullsfirst,
241 Plan *lefttree, Plan *righttree,
242 JoinType jointype, bool inner_unique,
243 bool skip_mark_restore);
244 static Sort *make_sort(Plan *lefttree, int numCols,
245 AttrNumber *sortColIdx, Oid *sortOperators,
246 Oid *collations, bool *nullsFirst);
247 static Plan *prepare_sort_from_pathkeys(Plan *lefttree, List *pathkeys,
248 Relids relids,
249 const AttrNumber *reqColIdx,
250 bool adjust_tlist_in_place,
251 int *p_numsortkeys,
252 AttrNumber **p_sortColIdx,
253 Oid **p_sortOperators,
254 Oid **p_collations,
255 bool **p_nullsFirst);
256 static EquivalenceMember *find_ec_member_for_tle(EquivalenceClass *ec,
257 TargetEntry *tle,
258 Relids relids);
259 static Sort *make_sort_from_pathkeys(Plan *lefttree, List *pathkeys,
260 Relids relids);
261 static Sort *make_sort_from_groupcols(List *groupcls,
262 AttrNumber *grpColIdx,
263 Plan *lefttree);
264 static Material *make_material(Plan *lefttree);
265 static WindowAgg *make_windowagg(List *tlist, Index winref,
266 int partNumCols, AttrNumber *partColIdx, Oid *partOperators, Oid *partCollations,
267 int ordNumCols, AttrNumber *ordColIdx, Oid *ordOperators, Oid *ordCollations,
268 int frameOptions, Node *startOffset, Node *endOffset,
269 Oid startInRangeFunc, Oid endInRangeFunc,
270 Oid inRangeColl, bool inRangeAsc, bool inRangeNullsFirst,
271 Plan *lefttree);
272 static Group *make_group(List *tlist, List *qual, int numGroupCols,
273 AttrNumber *grpColIdx, Oid *grpOperators, Oid *grpCollations,
274 Plan *lefttree);
275 static Unique *make_unique_from_sortclauses(Plan *lefttree, List *distinctList);
276 static Unique *make_unique_from_pathkeys(Plan *lefttree,
277 List *pathkeys, int numCols);
278 static Gather *make_gather(List *qptlist, List *qpqual,
279 int nworkers, int rescan_param, bool single_copy, Plan *subplan);
280 static SetOp *make_setop(SetOpCmd cmd, SetOpStrategy strategy, Plan *lefttree,
281 List *distinctList, AttrNumber flagColIdx, int firstFlag,
282 long numGroups);
283 static LockRows *make_lockrows(Plan *lefttree, List *rowMarks, int epqParam);
284 static Result *make_result(List *tlist, Node *resconstantqual, Plan *subplan);
285 static ProjectSet *make_project_set(List *tlist, Plan *subplan);
286 static ModifyTable *make_modifytable(PlannerInfo *root,
287 CmdType operation, bool canSetTag,
288 Index nominalRelation, Index rootRelation,
289 bool partColsUpdated,
290 List *resultRelations, List *subplans, List *subroots,
291 List *withCheckOptionLists, List *returningLists,
292 List *rowMarks, OnConflictExpr *onconflict, int epqParam);
293 static GatherMerge *create_gather_merge_plan(PlannerInfo *root,
294 GatherMergePath *best_path);
295
296
297 /*
298 * create_plan
299 * Creates the access plan for a query by recursively processing the
300 * desired tree of pathnodes, starting at the node 'best_path'. For
301 * every pathnode found, we create a corresponding plan node containing
302 * appropriate id, target list, and qualification information.
303 *
304 * The tlists and quals in the plan tree are still in planner format,
305 * ie, Vars still correspond to the parser's numbering. This will be
306 * fixed later by setrefs.c.
307 *
308 * best_path is the best access path
309 *
310 * Returns a Plan tree.
311 */
312 Plan *
create_plan(PlannerInfo * root,Path * best_path)313 create_plan(PlannerInfo *root, Path *best_path)
314 {
315 Plan *plan;
316
317 /* plan_params should not be in use in current query level */
318 Assert(root->plan_params == NIL);
319
320 /* Initialize this module's workspace in PlannerInfo */
321 root->curOuterRels = NULL;
322 root->curOuterParams = NIL;
323
324 /* Recursively process the path tree, demanding the correct tlist result */
325 plan = create_plan_recurse(root, best_path, CP_EXACT_TLIST);
326
327 /*
328 * Make sure the topmost plan node's targetlist exposes the original
329 * column names and other decorative info. Targetlists generated within
330 * the planner don't bother with that stuff, but we must have it on the
331 * top-level tlist seen at execution time. However, ModifyTable plan
332 * nodes don't have a tlist matching the querytree targetlist.
333 */
334 if (!IsA(plan, ModifyTable))
335 apply_tlist_labeling(plan->targetlist, root->processed_tlist);
336
337 /*
338 * Attach any initPlans created in this query level to the topmost plan
339 * node. (In principle the initplans could go in any plan node at or
340 * above where they're referenced, but there seems no reason to put them
341 * any lower than the topmost node for the query level. Also, see
342 * comments for SS_finalize_plan before you try to change this.)
343 */
344 SS_attach_initplans(root, plan);
345
346 /* Check we successfully assigned all NestLoopParams to plan nodes */
347 if (root->curOuterParams != NIL)
348 elog(ERROR, "failed to assign all NestLoopParams to plan nodes");
349
350 /*
351 * Reset plan_params to ensure param IDs used for nestloop params are not
352 * re-used later
353 */
354 root->plan_params = NIL;
355
356 return plan;
357 }
358
359 /*
360 * create_plan_recurse
361 * Recursive guts of create_plan().
362 */
363 static Plan *
create_plan_recurse(PlannerInfo * root,Path * best_path,int flags)364 create_plan_recurse(PlannerInfo *root, Path *best_path, int flags)
365 {
366 Plan *plan;
367
368 /* Guard against stack overflow due to overly complex plans */
369 check_stack_depth();
370
371 switch (best_path->pathtype)
372 {
373 case T_SeqScan:
374 case T_SampleScan:
375 case T_IndexScan:
376 case T_IndexOnlyScan:
377 case T_BitmapHeapScan:
378 case T_TidScan:
379 case T_SubqueryScan:
380 case T_FunctionScan:
381 case T_TableFuncScan:
382 case T_ValuesScan:
383 case T_CteScan:
384 case T_WorkTableScan:
385 case T_NamedTuplestoreScan:
386 case T_ForeignScan:
387 case T_CustomScan:
388 plan = create_scan_plan(root, best_path, flags);
389 break;
390 case T_HashJoin:
391 case T_MergeJoin:
392 case T_NestLoop:
393 plan = create_join_plan(root,
394 (JoinPath *) best_path);
395 break;
396 case T_Append:
397 plan = create_append_plan(root,
398 (AppendPath *) best_path,
399 flags);
400 break;
401 case T_MergeAppend:
402 plan = create_merge_append_plan(root,
403 (MergeAppendPath *) best_path,
404 flags);
405 break;
406 case T_Result:
407 if (IsA(best_path, ProjectionPath))
408 {
409 plan = create_projection_plan(root,
410 (ProjectionPath *) best_path,
411 flags);
412 }
413 else if (IsA(best_path, MinMaxAggPath))
414 {
415 plan = (Plan *) create_minmaxagg_plan(root,
416 (MinMaxAggPath *) best_path);
417 }
418 else if (IsA(best_path, GroupResultPath))
419 {
420 plan = (Plan *) create_group_result_plan(root,
421 (GroupResultPath *) best_path);
422 }
423 else
424 {
425 /* Simple RTE_RESULT base relation */
426 Assert(IsA(best_path, Path));
427 plan = create_scan_plan(root, best_path, flags);
428 }
429 break;
430 case T_ProjectSet:
431 plan = (Plan *) create_project_set_plan(root,
432 (ProjectSetPath *) best_path);
433 break;
434 case T_Material:
435 plan = (Plan *) create_material_plan(root,
436 (MaterialPath *) best_path,
437 flags);
438 break;
439 case T_Unique:
440 if (IsA(best_path, UpperUniquePath))
441 {
442 plan = (Plan *) create_upper_unique_plan(root,
443 (UpperUniquePath *) best_path,
444 flags);
445 }
446 else
447 {
448 Assert(IsA(best_path, UniquePath));
449 plan = create_unique_plan(root,
450 (UniquePath *) best_path,
451 flags);
452 }
453 break;
454 case T_Gather:
455 plan = (Plan *) create_gather_plan(root,
456 (GatherPath *) best_path);
457 break;
458 case T_Sort:
459 plan = (Plan *) create_sort_plan(root,
460 (SortPath *) best_path,
461 flags);
462 break;
463 case T_Group:
464 plan = (Plan *) create_group_plan(root,
465 (GroupPath *) best_path);
466 break;
467 case T_Agg:
468 if (IsA(best_path, GroupingSetsPath))
469 plan = create_groupingsets_plan(root,
470 (GroupingSetsPath *) best_path);
471 else
472 {
473 Assert(IsA(best_path, AggPath));
474 plan = (Plan *) create_agg_plan(root,
475 (AggPath *) best_path);
476 }
477 break;
478 case T_WindowAgg:
479 plan = (Plan *) create_windowagg_plan(root,
480 (WindowAggPath *) best_path);
481 break;
482 case T_SetOp:
483 plan = (Plan *) create_setop_plan(root,
484 (SetOpPath *) best_path,
485 flags);
486 break;
487 case T_RecursiveUnion:
488 plan = (Plan *) create_recursiveunion_plan(root,
489 (RecursiveUnionPath *) best_path);
490 break;
491 case T_LockRows:
492 plan = (Plan *) create_lockrows_plan(root,
493 (LockRowsPath *) best_path,
494 flags);
495 break;
496 case T_ModifyTable:
497 plan = (Plan *) create_modifytable_plan(root,
498 (ModifyTablePath *) best_path);
499 break;
500 case T_Limit:
501 plan = (Plan *) create_limit_plan(root,
502 (LimitPath *) best_path,
503 flags);
504 break;
505 case T_GatherMerge:
506 plan = (Plan *) create_gather_merge_plan(root,
507 (GatherMergePath *) best_path);
508 break;
509 default:
510 elog(ERROR, "unrecognized node type: %d",
511 (int) best_path->pathtype);
512 plan = NULL; /* keep compiler quiet */
513 break;
514 }
515
516 return plan;
517 }
518
519 /*
520 * create_scan_plan
521 * Create a scan plan for the parent relation of 'best_path'.
522 */
523 static Plan *
create_scan_plan(PlannerInfo * root,Path * best_path,int flags)524 create_scan_plan(PlannerInfo *root, Path *best_path, int flags)
525 {
526 RelOptInfo *rel = best_path->parent;
527 List *scan_clauses;
528 List *gating_clauses;
529 List *tlist;
530 Plan *plan;
531
532 /*
533 * Extract the relevant restriction clauses from the parent relation. The
534 * executor must apply all these restrictions during the scan, except for
535 * pseudoconstants which we'll take care of below.
536 *
537 * If this is a plain indexscan or index-only scan, we need not consider
538 * restriction clauses that are implied by the index's predicate, so use
539 * indrestrictinfo not baserestrictinfo. Note that we can't do that for
540 * bitmap indexscans, since there's not necessarily a single index
541 * involved; but it doesn't matter since create_bitmap_scan_plan() will be
542 * able to get rid of such clauses anyway via predicate proof.
543 */
544 switch (best_path->pathtype)
545 {
546 case T_IndexScan:
547 case T_IndexOnlyScan:
548 scan_clauses = castNode(IndexPath, best_path)->indexinfo->indrestrictinfo;
549 break;
550 default:
551 scan_clauses = rel->baserestrictinfo;
552 break;
553 }
554
555 /*
556 * If this is a parameterized scan, we also need to enforce all the join
557 * clauses available from the outer relation(s).
558 *
559 * For paranoia's sake, don't modify the stored baserestrictinfo list.
560 */
561 if (best_path->param_info)
562 scan_clauses = list_concat(list_copy(scan_clauses),
563 best_path->param_info->ppi_clauses);
564
565 /*
566 * Detect whether we have any pseudoconstant quals to deal with. Then, if
567 * we'll need a gating Result node, it will be able to project, so there
568 * are no requirements on the child's tlist.
569 */
570 gating_clauses = get_gating_quals(root, scan_clauses);
571 if (gating_clauses)
572 flags = 0;
573
574 /*
575 * For table scans, rather than using the relation targetlist (which is
576 * only those Vars actually needed by the query), we prefer to generate a
577 * tlist containing all Vars in order. This will allow the executor to
578 * optimize away projection of the table tuples, if possible.
579 *
580 * But if the caller is going to ignore our tlist anyway, then don't
581 * bother generating one at all. We use an exact equality test here, so
582 * that this only applies when CP_IGNORE_TLIST is the only flag set.
583 */
584 if (flags == CP_IGNORE_TLIST)
585 {
586 tlist = NULL;
587 }
588 else if (use_physical_tlist(root, best_path, flags))
589 {
590 if (best_path->pathtype == T_IndexOnlyScan)
591 {
592 /* For index-only scan, the preferred tlist is the index's */
593 tlist = copyObject(((IndexPath *) best_path)->indexinfo->indextlist);
594
595 /*
596 * Transfer sortgroupref data to the replacement tlist, if
597 * requested (use_physical_tlist checked that this will work).
598 */
599 if (flags & CP_LABEL_TLIST)
600 apply_pathtarget_labeling_to_tlist(tlist, best_path->pathtarget);
601 }
602 else
603 {
604 tlist = build_physical_tlist(root, rel);
605 if (tlist == NIL)
606 {
607 /* Failed because of dropped cols, so use regular method */
608 tlist = build_path_tlist(root, best_path);
609 }
610 else
611 {
612 /* As above, transfer sortgroupref data to replacement tlist */
613 if (flags & CP_LABEL_TLIST)
614 apply_pathtarget_labeling_to_tlist(tlist, best_path->pathtarget);
615 }
616 }
617 }
618 else
619 {
620 tlist = build_path_tlist(root, best_path);
621 }
622
623 switch (best_path->pathtype)
624 {
625 case T_SeqScan:
626 plan = (Plan *) create_seqscan_plan(root,
627 best_path,
628 tlist,
629 scan_clauses);
630 break;
631
632 case T_SampleScan:
633 plan = (Plan *) create_samplescan_plan(root,
634 best_path,
635 tlist,
636 scan_clauses);
637 break;
638
639 case T_IndexScan:
640 plan = (Plan *) create_indexscan_plan(root,
641 (IndexPath *) best_path,
642 tlist,
643 scan_clauses,
644 false);
645 break;
646
647 case T_IndexOnlyScan:
648 plan = (Plan *) create_indexscan_plan(root,
649 (IndexPath *) best_path,
650 tlist,
651 scan_clauses,
652 true);
653 break;
654
655 case T_BitmapHeapScan:
656 plan = (Plan *) create_bitmap_scan_plan(root,
657 (BitmapHeapPath *) best_path,
658 tlist,
659 scan_clauses);
660 break;
661
662 case T_TidScan:
663 plan = (Plan *) create_tidscan_plan(root,
664 (TidPath *) best_path,
665 tlist,
666 scan_clauses);
667 break;
668
669 case T_SubqueryScan:
670 plan = (Plan *) create_subqueryscan_plan(root,
671 (SubqueryScanPath *) best_path,
672 tlist,
673 scan_clauses);
674 break;
675
676 case T_FunctionScan:
677 plan = (Plan *) create_functionscan_plan(root,
678 best_path,
679 tlist,
680 scan_clauses);
681 break;
682
683 case T_TableFuncScan:
684 plan = (Plan *) create_tablefuncscan_plan(root,
685 best_path,
686 tlist,
687 scan_clauses);
688 break;
689
690 case T_ValuesScan:
691 plan = (Plan *) create_valuesscan_plan(root,
692 best_path,
693 tlist,
694 scan_clauses);
695 break;
696
697 case T_CteScan:
698 plan = (Plan *) create_ctescan_plan(root,
699 best_path,
700 tlist,
701 scan_clauses);
702 break;
703
704 case T_NamedTuplestoreScan:
705 plan = (Plan *) create_namedtuplestorescan_plan(root,
706 best_path,
707 tlist,
708 scan_clauses);
709 break;
710
711 case T_Result:
712 plan = (Plan *) create_resultscan_plan(root,
713 best_path,
714 tlist,
715 scan_clauses);
716 break;
717
718 case T_WorkTableScan:
719 plan = (Plan *) create_worktablescan_plan(root,
720 best_path,
721 tlist,
722 scan_clauses);
723 break;
724
725 case T_ForeignScan:
726 plan = (Plan *) create_foreignscan_plan(root,
727 (ForeignPath *) best_path,
728 tlist,
729 scan_clauses);
730 break;
731
732 case T_CustomScan:
733 plan = (Plan *) create_customscan_plan(root,
734 (CustomPath *) best_path,
735 tlist,
736 scan_clauses);
737 break;
738
739 default:
740 elog(ERROR, "unrecognized node type: %d",
741 (int) best_path->pathtype);
742 plan = NULL; /* keep compiler quiet */
743 break;
744 }
745
746 /*
747 * If there are any pseudoconstant clauses attached to this node, insert a
748 * gating Result node that evaluates the pseudoconstants as one-time
749 * quals.
750 */
751 if (gating_clauses)
752 plan = create_gating_plan(root, best_path, plan, gating_clauses);
753
754 return plan;
755 }
756
757 /*
758 * Build a target list (ie, a list of TargetEntry) for the Path's output.
759 *
760 * This is almost just make_tlist_from_pathtarget(), but we also have to
761 * deal with replacing nestloop params.
762 */
763 static List *
build_path_tlist(PlannerInfo * root,Path * path)764 build_path_tlist(PlannerInfo *root, Path *path)
765 {
766 List *tlist = NIL;
767 Index *sortgrouprefs = path->pathtarget->sortgrouprefs;
768 int resno = 1;
769 ListCell *v;
770
771 foreach(v, path->pathtarget->exprs)
772 {
773 Node *node = (Node *) lfirst(v);
774 TargetEntry *tle;
775
776 /*
777 * If it's a parameterized path, there might be lateral references in
778 * the tlist, which need to be replaced with Params. There's no need
779 * to remake the TargetEntry nodes, so apply this to each list item
780 * separately.
781 */
782 if (path->param_info)
783 node = replace_nestloop_params(root, node);
784
785 tle = makeTargetEntry((Expr *) node,
786 resno,
787 NULL,
788 false);
789 if (sortgrouprefs)
790 tle->ressortgroupref = sortgrouprefs[resno - 1];
791
792 tlist = lappend(tlist, tle);
793 resno++;
794 }
795 return tlist;
796 }
797
798 /*
799 * use_physical_tlist
800 * Decide whether to use a tlist matching relation structure,
801 * rather than only those Vars actually referenced.
802 */
803 static bool
use_physical_tlist(PlannerInfo * root,Path * path,int flags)804 use_physical_tlist(PlannerInfo *root, Path *path, int flags)
805 {
806 RelOptInfo *rel = path->parent;
807 int i;
808 ListCell *lc;
809
810 /*
811 * Forget it if either exact tlist or small tlist is demanded.
812 */
813 if (flags & (CP_EXACT_TLIST | CP_SMALL_TLIST))
814 return false;
815
816 /*
817 * We can do this for real relation scans, subquery scans, function scans,
818 * tablefunc scans, values scans, and CTE scans (but not for, eg, joins).
819 */
820 if (rel->rtekind != RTE_RELATION &&
821 rel->rtekind != RTE_SUBQUERY &&
822 rel->rtekind != RTE_FUNCTION &&
823 rel->rtekind != RTE_TABLEFUNC &&
824 rel->rtekind != RTE_VALUES &&
825 rel->rtekind != RTE_CTE)
826 return false;
827
828 /*
829 * Can't do it with inheritance cases either (mainly because Append
830 * doesn't project; this test may be unnecessary now that
831 * create_append_plan instructs its children to return an exact tlist).
832 */
833 if (rel->reloptkind != RELOPT_BASEREL)
834 return false;
835
836 /*
837 * Also, don't do it to a CustomPath; the premise that we're extracting
838 * columns from a simple physical tuple is unlikely to hold for those.
839 * (When it does make sense, the custom path creator can set up the path's
840 * pathtarget that way.)
841 */
842 if (IsA(path, CustomPath))
843 return false;
844
845 /*
846 * If a bitmap scan's tlist is empty, keep it as-is. This may allow the
847 * executor to skip heap page fetches, and in any case, the benefit of
848 * using a physical tlist instead would be minimal.
849 */
850 if (IsA(path, BitmapHeapPath) &&
851 path->pathtarget->exprs == NIL)
852 return false;
853
854 /*
855 * Can't do it if any system columns or whole-row Vars are requested.
856 * (This could possibly be fixed but would take some fragile assumptions
857 * in setrefs.c, I think.)
858 */
859 for (i = rel->min_attr; i <= 0; i++)
860 {
861 if (!bms_is_empty(rel->attr_needed[i - rel->min_attr]))
862 return false;
863 }
864
865 /*
866 * Can't do it if the rel is required to emit any placeholder expressions,
867 * either.
868 */
869 foreach(lc, root->placeholder_list)
870 {
871 PlaceHolderInfo *phinfo = (PlaceHolderInfo *) lfirst(lc);
872
873 if (bms_nonempty_difference(phinfo->ph_needed, rel->relids) &&
874 bms_is_subset(phinfo->ph_eval_at, rel->relids))
875 return false;
876 }
877
878 /*
879 * Also, can't do it if CP_LABEL_TLIST is specified and path is requested
880 * to emit any sort/group columns that are not simple Vars. (If they are
881 * simple Vars, they should appear in the physical tlist, and
882 * apply_pathtarget_labeling_to_tlist will take care of getting them
883 * labeled again.) We also have to check that no two sort/group columns
884 * are the same Var, else that element of the physical tlist would need
885 * conflicting ressortgroupref labels.
886 */
887 if ((flags & CP_LABEL_TLIST) && path->pathtarget->sortgrouprefs)
888 {
889 Bitmapset *sortgroupatts = NULL;
890
891 i = 0;
892 foreach(lc, path->pathtarget->exprs)
893 {
894 Expr *expr = (Expr *) lfirst(lc);
895
896 if (path->pathtarget->sortgrouprefs[i])
897 {
898 if (expr && IsA(expr, Var))
899 {
900 int attno = ((Var *) expr)->varattno;
901
902 attno -= FirstLowInvalidHeapAttributeNumber;
903 if (bms_is_member(attno, sortgroupatts))
904 return false;
905 sortgroupatts = bms_add_member(sortgroupatts, attno);
906 }
907 else
908 return false;
909 }
910 i++;
911 }
912 }
913
914 return true;
915 }
916
917 /*
918 * get_gating_quals
919 * See if there are pseudoconstant quals in a node's quals list
920 *
921 * If the node's quals list includes any pseudoconstant quals,
922 * return just those quals.
923 */
924 static List *
get_gating_quals(PlannerInfo * root,List * quals)925 get_gating_quals(PlannerInfo *root, List *quals)
926 {
927 /* No need to look if we know there are no pseudoconstants */
928 if (!root->hasPseudoConstantQuals)
929 return NIL;
930
931 /* Sort into desirable execution order while still in RestrictInfo form */
932 quals = order_qual_clauses(root, quals);
933
934 /* Pull out any pseudoconstant quals from the RestrictInfo list */
935 return extract_actual_clauses(quals, true);
936 }
937
938 /*
939 * create_gating_plan
940 * Deal with pseudoconstant qual clauses
941 *
942 * Add a gating Result node atop the already-built plan.
943 */
944 static Plan *
create_gating_plan(PlannerInfo * root,Path * path,Plan * plan,List * gating_quals)945 create_gating_plan(PlannerInfo *root, Path *path, Plan *plan,
946 List *gating_quals)
947 {
948 Plan *gplan;
949 Plan *splan;
950
951 Assert(gating_quals);
952
953 /*
954 * We might have a trivial Result plan already. Stacking one Result atop
955 * another is silly, so if that applies, just discard the input plan.
956 * (We're assuming its targetlist is uninteresting; it should be either
957 * the same as the result of build_path_tlist, or a simplified version.)
958 */
959 splan = plan;
960 if (IsA(plan, Result))
961 {
962 Result *rplan = (Result *) plan;
963
964 if (rplan->plan.lefttree == NULL &&
965 rplan->resconstantqual == NULL)
966 splan = NULL;
967 }
968
969 /*
970 * Since we need a Result node anyway, always return the path's requested
971 * tlist; that's never a wrong choice, even if the parent node didn't ask
972 * for CP_EXACT_TLIST.
973 */
974 gplan = (Plan *) make_result(build_path_tlist(root, path),
975 (Node *) gating_quals,
976 splan);
977
978 /*
979 * Notice that we don't change cost or size estimates when doing gating.
980 * The costs of qual eval were already included in the subplan's cost.
981 * Leaving the size alone amounts to assuming that the gating qual will
982 * succeed, which is the conservative estimate for planning upper queries.
983 * We certainly don't want to assume the output size is zero (unless the
984 * gating qual is actually constant FALSE, and that case is dealt with in
985 * clausesel.c). Interpolating between the two cases is silly, because it
986 * doesn't reflect what will really happen at runtime, and besides which
987 * in most cases we have only a very bad idea of the probability of the
988 * gating qual being true.
989 */
990 copy_plan_costsize(gplan, plan);
991
992 /* Gating quals could be unsafe, so better use the Path's safety flag */
993 gplan->parallel_safe = path->parallel_safe;
994
995 return gplan;
996 }
997
998 /*
999 * create_join_plan
1000 * Create a join plan for 'best_path' and (recursively) plans for its
1001 * inner and outer paths.
1002 */
1003 static Plan *
create_join_plan(PlannerInfo * root,JoinPath * best_path)1004 create_join_plan(PlannerInfo *root, JoinPath *best_path)
1005 {
1006 Plan *plan;
1007 List *gating_clauses;
1008
1009 switch (best_path->path.pathtype)
1010 {
1011 case T_MergeJoin:
1012 plan = (Plan *) create_mergejoin_plan(root,
1013 (MergePath *) best_path);
1014 break;
1015 case T_HashJoin:
1016 plan = (Plan *) create_hashjoin_plan(root,
1017 (HashPath *) best_path);
1018 break;
1019 case T_NestLoop:
1020 plan = (Plan *) create_nestloop_plan(root,
1021 (NestPath *) best_path);
1022 break;
1023 default:
1024 elog(ERROR, "unrecognized node type: %d",
1025 (int) best_path->path.pathtype);
1026 plan = NULL; /* keep compiler quiet */
1027 break;
1028 }
1029
1030 /*
1031 * If there are any pseudoconstant clauses attached to this node, insert a
1032 * gating Result node that evaluates the pseudoconstants as one-time
1033 * quals.
1034 */
1035 gating_clauses = get_gating_quals(root, best_path->joinrestrictinfo);
1036 if (gating_clauses)
1037 plan = create_gating_plan(root, (Path *) best_path, plan,
1038 gating_clauses);
1039
1040 #ifdef NOT_USED
1041
1042 /*
1043 * * Expensive function pullups may have pulled local predicates * into
1044 * this path node. Put them in the qpqual of the plan node. * JMH,
1045 * 6/15/92
1046 */
1047 if (get_loc_restrictinfo(best_path) != NIL)
1048 set_qpqual((Plan) plan,
1049 list_concat(get_qpqual((Plan) plan),
1050 get_actual_clauses(get_loc_restrictinfo(best_path))));
1051 #endif
1052
1053 return plan;
1054 }
1055
1056 /*
1057 * create_append_plan
1058 * Create an Append plan for 'best_path' and (recursively) plans
1059 * for its subpaths.
1060 *
1061 * Returns a Plan node.
1062 */
1063 static Plan *
create_append_plan(PlannerInfo * root,AppendPath * best_path,int flags)1064 create_append_plan(PlannerInfo *root, AppendPath *best_path, int flags)
1065 {
1066 Append *plan;
1067 List *tlist = build_path_tlist(root, &best_path->path);
1068 int orig_tlist_length = list_length(tlist);
1069 bool tlist_was_changed = false;
1070 List *pathkeys = best_path->path.pathkeys;
1071 List *subplans = NIL;
1072 ListCell *subpaths;
1073 RelOptInfo *rel = best_path->path.parent;
1074 PartitionPruneInfo *partpruneinfo = NULL;
1075 int nodenumsortkeys = 0;
1076 AttrNumber *nodeSortColIdx = NULL;
1077 Oid *nodeSortOperators = NULL;
1078 Oid *nodeCollations = NULL;
1079 bool *nodeNullsFirst = NULL;
1080
1081 /*
1082 * The subpaths list could be empty, if every child was proven empty by
1083 * constraint exclusion. In that case generate a dummy plan that returns
1084 * no rows.
1085 *
1086 * Note that an AppendPath with no members is also generated in certain
1087 * cases where there was no appending construct at all, but we know the
1088 * relation is empty (see set_dummy_rel_pathlist and mark_dummy_rel).
1089 */
1090 if (best_path->subpaths == NIL)
1091 {
1092 /* Generate a Result plan with constant-FALSE gating qual */
1093 Plan *plan;
1094
1095 plan = (Plan *) make_result(tlist,
1096 (Node *) list_make1(makeBoolConst(false,
1097 false)),
1098 NULL);
1099
1100 copy_generic_path_info(plan, (Path *) best_path);
1101
1102 return plan;
1103 }
1104
1105 /*
1106 * Otherwise build an Append plan. Note that if there's just one child,
1107 * the Append is pretty useless; but we wait till setrefs.c to get rid of
1108 * it. Doing so here doesn't work because the varno of the child scan
1109 * plan won't match the parent-rel Vars it'll be asked to emit.
1110 *
1111 * We don't have the actual creation of the Append node split out into a
1112 * separate make_xxx function. This is because we want to run
1113 * prepare_sort_from_pathkeys on it before we do so on the individual
1114 * child plans, to make cross-checking the sort info easier.
1115 */
1116 plan = makeNode(Append);
1117 plan->plan.targetlist = tlist;
1118 plan->plan.qual = NIL;
1119 plan->plan.lefttree = NULL;
1120 plan->plan.righttree = NULL;
1121
1122 if (pathkeys != NIL)
1123 {
1124 /*
1125 * Compute sort column info, and adjust the Append's tlist as needed.
1126 * Because we pass adjust_tlist_in_place = true, we may ignore the
1127 * function result; it must be the same plan node. However, we then
1128 * need to detect whether any tlist entries were added.
1129 */
1130 (void) prepare_sort_from_pathkeys((Plan *) plan, pathkeys,
1131 best_path->path.parent->relids,
1132 NULL,
1133 true,
1134 &nodenumsortkeys,
1135 &nodeSortColIdx,
1136 &nodeSortOperators,
1137 &nodeCollations,
1138 &nodeNullsFirst);
1139 tlist_was_changed = (orig_tlist_length != list_length(plan->plan.targetlist));
1140 }
1141
1142 /* Build the plan for each child */
1143 foreach(subpaths, best_path->subpaths)
1144 {
1145 Path *subpath = (Path *) lfirst(subpaths);
1146 Plan *subplan;
1147
1148 /* Must insist that all children return the same tlist */
1149 subplan = create_plan_recurse(root, subpath, CP_EXACT_TLIST);
1150
1151 /*
1152 * For ordered Appends, we must insert a Sort node if subplan isn't
1153 * sufficiently ordered.
1154 */
1155 if (pathkeys != NIL)
1156 {
1157 int numsortkeys;
1158 AttrNumber *sortColIdx;
1159 Oid *sortOperators;
1160 Oid *collations;
1161 bool *nullsFirst;
1162
1163 /*
1164 * Compute sort column info, and adjust subplan's tlist as needed.
1165 * We must apply prepare_sort_from_pathkeys even to subplans that
1166 * don't need an explicit sort, to make sure they are returning
1167 * the same sort key columns the Append expects.
1168 */
1169 subplan = prepare_sort_from_pathkeys(subplan, pathkeys,
1170 subpath->parent->relids,
1171 nodeSortColIdx,
1172 false,
1173 &numsortkeys,
1174 &sortColIdx,
1175 &sortOperators,
1176 &collations,
1177 &nullsFirst);
1178
1179 /*
1180 * Check that we got the same sort key information. We just
1181 * Assert that the sortops match, since those depend only on the
1182 * pathkeys; but it seems like a good idea to check the sort
1183 * column numbers explicitly, to ensure the tlists match up.
1184 */
1185 Assert(numsortkeys == nodenumsortkeys);
1186 if (memcmp(sortColIdx, nodeSortColIdx,
1187 numsortkeys * sizeof(AttrNumber)) != 0)
1188 elog(ERROR, "Append child's targetlist doesn't match Append");
1189 Assert(memcmp(sortOperators, nodeSortOperators,
1190 numsortkeys * sizeof(Oid)) == 0);
1191 Assert(memcmp(collations, nodeCollations,
1192 numsortkeys * sizeof(Oid)) == 0);
1193 Assert(memcmp(nullsFirst, nodeNullsFirst,
1194 numsortkeys * sizeof(bool)) == 0);
1195
1196 /* Now, insert a Sort node if subplan isn't sufficiently ordered */
1197 if (!pathkeys_contained_in(pathkeys, subpath->pathkeys))
1198 {
1199 Sort *sort = make_sort(subplan, numsortkeys,
1200 sortColIdx, sortOperators,
1201 collations, nullsFirst);
1202
1203 label_sort_with_costsize(root, sort, best_path->limit_tuples);
1204 subplan = (Plan *) sort;
1205 }
1206 }
1207
1208 subplans = lappend(subplans, subplan);
1209 }
1210
1211 /*
1212 * If any quals exist, they may be useful to perform further partition
1213 * pruning during execution. Gather information needed by the executor to
1214 * do partition pruning.
1215 */
1216 if (enable_partition_pruning &&
1217 rel->reloptkind == RELOPT_BASEREL &&
1218 best_path->partitioned_rels != NIL)
1219 {
1220 List *prunequal;
1221
1222 prunequal = extract_actual_clauses(rel->baserestrictinfo, false);
1223
1224 if (best_path->path.param_info)
1225 {
1226 List *prmquals = best_path->path.param_info->ppi_clauses;
1227
1228 prmquals = extract_actual_clauses(prmquals, false);
1229 prmquals = (List *) replace_nestloop_params(root,
1230 (Node *) prmquals);
1231
1232 prunequal = list_concat(prunequal, prmquals);
1233 }
1234
1235 if (prunequal != NIL)
1236 partpruneinfo =
1237 make_partition_pruneinfo(root, rel,
1238 best_path->subpaths,
1239 best_path->partitioned_rels,
1240 prunequal);
1241 }
1242
1243 plan->appendplans = subplans;
1244 plan->first_partial_plan = best_path->first_partial_path;
1245 plan->part_prune_info = partpruneinfo;
1246
1247 copy_generic_path_info(&plan->plan, (Path *) best_path);
1248
1249 /*
1250 * If prepare_sort_from_pathkeys added sort columns, but we were told to
1251 * produce either the exact tlist or a narrow tlist, we should get rid of
1252 * the sort columns again. We must inject a projection node to do so.
1253 */
1254 if (tlist_was_changed && (flags & (CP_EXACT_TLIST | CP_SMALL_TLIST)))
1255 {
1256 tlist = list_truncate(list_copy(plan->plan.targetlist),
1257 orig_tlist_length);
1258 return inject_projection_plan((Plan *) plan, tlist,
1259 plan->plan.parallel_safe);
1260 }
1261 else
1262 return (Plan *) plan;
1263 }
1264
1265 /*
1266 * create_merge_append_plan
1267 * Create a MergeAppend plan for 'best_path' and (recursively) plans
1268 * for its subpaths.
1269 *
1270 * Returns a Plan node.
1271 */
1272 static Plan *
create_merge_append_plan(PlannerInfo * root,MergeAppendPath * best_path,int flags)1273 create_merge_append_plan(PlannerInfo *root, MergeAppendPath *best_path,
1274 int flags)
1275 {
1276 MergeAppend *node = makeNode(MergeAppend);
1277 Plan *plan = &node->plan;
1278 List *tlist = build_path_tlist(root, &best_path->path);
1279 int orig_tlist_length = list_length(tlist);
1280 bool tlist_was_changed;
1281 List *pathkeys = best_path->path.pathkeys;
1282 List *subplans = NIL;
1283 ListCell *subpaths;
1284 RelOptInfo *rel = best_path->path.parent;
1285 PartitionPruneInfo *partpruneinfo = NULL;
1286
1287 /*
1288 * We don't have the actual creation of the MergeAppend node split out
1289 * into a separate make_xxx function. This is because we want to run
1290 * prepare_sort_from_pathkeys on it before we do so on the individual
1291 * child plans, to make cross-checking the sort info easier.
1292 */
1293 copy_generic_path_info(plan, (Path *) best_path);
1294 plan->targetlist = tlist;
1295 plan->qual = NIL;
1296 plan->lefttree = NULL;
1297 plan->righttree = NULL;
1298
1299 /*
1300 * Compute sort column info, and adjust MergeAppend's tlist as needed.
1301 * Because we pass adjust_tlist_in_place = true, we may ignore the
1302 * function result; it must be the same plan node. However, we then need
1303 * to detect whether any tlist entries were added.
1304 */
1305 (void) prepare_sort_from_pathkeys(plan, pathkeys,
1306 best_path->path.parent->relids,
1307 NULL,
1308 true,
1309 &node->numCols,
1310 &node->sortColIdx,
1311 &node->sortOperators,
1312 &node->collations,
1313 &node->nullsFirst);
1314 tlist_was_changed = (orig_tlist_length != list_length(plan->targetlist));
1315
1316 /*
1317 * Now prepare the child plans. We must apply prepare_sort_from_pathkeys
1318 * even to subplans that don't need an explicit sort, to make sure they
1319 * are returning the same sort key columns the MergeAppend expects.
1320 */
1321 foreach(subpaths, best_path->subpaths)
1322 {
1323 Path *subpath = (Path *) lfirst(subpaths);
1324 Plan *subplan;
1325 int numsortkeys;
1326 AttrNumber *sortColIdx;
1327 Oid *sortOperators;
1328 Oid *collations;
1329 bool *nullsFirst;
1330
1331 /* Build the child plan */
1332 /* Must insist that all children return the same tlist */
1333 subplan = create_plan_recurse(root, subpath, CP_EXACT_TLIST);
1334
1335 /* Compute sort column info, and adjust subplan's tlist as needed */
1336 subplan = prepare_sort_from_pathkeys(subplan, pathkeys,
1337 subpath->parent->relids,
1338 node->sortColIdx,
1339 false,
1340 &numsortkeys,
1341 &sortColIdx,
1342 &sortOperators,
1343 &collations,
1344 &nullsFirst);
1345
1346 /*
1347 * Check that we got the same sort key information. We just Assert
1348 * that the sortops match, since those depend only on the pathkeys;
1349 * but it seems like a good idea to check the sort column numbers
1350 * explicitly, to ensure the tlists really do match up.
1351 */
1352 Assert(numsortkeys == node->numCols);
1353 if (memcmp(sortColIdx, node->sortColIdx,
1354 numsortkeys * sizeof(AttrNumber)) != 0)
1355 elog(ERROR, "MergeAppend child's targetlist doesn't match MergeAppend");
1356 Assert(memcmp(sortOperators, node->sortOperators,
1357 numsortkeys * sizeof(Oid)) == 0);
1358 Assert(memcmp(collations, node->collations,
1359 numsortkeys * sizeof(Oid)) == 0);
1360 Assert(memcmp(nullsFirst, node->nullsFirst,
1361 numsortkeys * sizeof(bool)) == 0);
1362
1363 /* Now, insert a Sort node if subplan isn't sufficiently ordered */
1364 if (!pathkeys_contained_in(pathkeys, subpath->pathkeys))
1365 {
1366 Sort *sort = make_sort(subplan, numsortkeys,
1367 sortColIdx, sortOperators,
1368 collations, nullsFirst);
1369
1370 label_sort_with_costsize(root, sort, best_path->limit_tuples);
1371 subplan = (Plan *) sort;
1372 }
1373
1374 subplans = lappend(subplans, subplan);
1375 }
1376
1377 /*
1378 * If any quals exist, they may be useful to perform further partition
1379 * pruning during execution. Gather information needed by the executor to
1380 * do partition pruning.
1381 */
1382 if (enable_partition_pruning &&
1383 rel->reloptkind == RELOPT_BASEREL &&
1384 best_path->partitioned_rels != NIL)
1385 {
1386 List *prunequal;
1387
1388 prunequal = extract_actual_clauses(rel->baserestrictinfo, false);
1389
1390 if (best_path->path.param_info)
1391 {
1392 List *prmquals = best_path->path.param_info->ppi_clauses;
1393
1394 prmquals = extract_actual_clauses(prmquals, false);
1395 prmquals = (List *) replace_nestloop_params(root,
1396 (Node *) prmquals);
1397
1398 prunequal = list_concat(prunequal, prmquals);
1399 }
1400
1401 if (prunequal != NIL)
1402 partpruneinfo = make_partition_pruneinfo(root, rel,
1403 best_path->subpaths,
1404 best_path->partitioned_rels,
1405 prunequal);
1406 }
1407
1408 node->mergeplans = subplans;
1409 node->part_prune_info = partpruneinfo;
1410
1411 /*
1412 * If prepare_sort_from_pathkeys added sort columns, but we were told to
1413 * produce either the exact tlist or a narrow tlist, we should get rid of
1414 * the sort columns again. We must inject a projection node to do so.
1415 */
1416 if (tlist_was_changed && (flags & (CP_EXACT_TLIST | CP_SMALL_TLIST)))
1417 {
1418 tlist = list_truncate(list_copy(plan->targetlist), orig_tlist_length);
1419 return inject_projection_plan(plan, tlist, plan->parallel_safe);
1420 }
1421 else
1422 return plan;
1423 }
1424
1425 /*
1426 * create_group_result_plan
1427 * Create a Result plan for 'best_path'.
1428 * This is only used for degenerate grouping cases.
1429 *
1430 * Returns a Plan node.
1431 */
1432 static Result *
create_group_result_plan(PlannerInfo * root,GroupResultPath * best_path)1433 create_group_result_plan(PlannerInfo *root, GroupResultPath *best_path)
1434 {
1435 Result *plan;
1436 List *tlist;
1437 List *quals;
1438
1439 tlist = build_path_tlist(root, &best_path->path);
1440
1441 /* best_path->quals is just bare clauses */
1442 quals = order_qual_clauses(root, best_path->quals);
1443
1444 plan = make_result(tlist, (Node *) quals, NULL);
1445
1446 copy_generic_path_info(&plan->plan, (Path *) best_path);
1447
1448 return plan;
1449 }
1450
1451 /*
1452 * create_project_set_plan
1453 * Create a ProjectSet plan for 'best_path'.
1454 *
1455 * Returns a Plan node.
1456 */
1457 static ProjectSet *
create_project_set_plan(PlannerInfo * root,ProjectSetPath * best_path)1458 create_project_set_plan(PlannerInfo *root, ProjectSetPath *best_path)
1459 {
1460 ProjectSet *plan;
1461 Plan *subplan;
1462 List *tlist;
1463
1464 /* Since we intend to project, we don't need to constrain child tlist */
1465 subplan = create_plan_recurse(root, best_path->subpath, 0);
1466
1467 tlist = build_path_tlist(root, &best_path->path);
1468
1469 plan = make_project_set(tlist, subplan);
1470
1471 copy_generic_path_info(&plan->plan, (Path *) best_path);
1472
1473 return plan;
1474 }
1475
1476 /*
1477 * create_material_plan
1478 * Create a Material plan for 'best_path' and (recursively) plans
1479 * for its subpaths.
1480 *
1481 * Returns a Plan node.
1482 */
1483 static Material *
create_material_plan(PlannerInfo * root,MaterialPath * best_path,int flags)1484 create_material_plan(PlannerInfo *root, MaterialPath *best_path, int flags)
1485 {
1486 Material *plan;
1487 Plan *subplan;
1488
1489 /*
1490 * We don't want any excess columns in the materialized tuples, so request
1491 * a smaller tlist. Otherwise, since Material doesn't project, tlist
1492 * requirements pass through.
1493 */
1494 subplan = create_plan_recurse(root, best_path->subpath,
1495 flags | CP_SMALL_TLIST);
1496
1497 plan = make_material(subplan);
1498
1499 copy_generic_path_info(&plan->plan, (Path *) best_path);
1500
1501 return plan;
1502 }
1503
1504 /*
1505 * create_unique_plan
1506 * Create a Unique plan for 'best_path' and (recursively) plans
1507 * for its subpaths.
1508 *
1509 * Returns a Plan node.
1510 */
1511 static Plan *
create_unique_plan(PlannerInfo * root,UniquePath * best_path,int flags)1512 create_unique_plan(PlannerInfo *root, UniquePath *best_path, int flags)
1513 {
1514 Plan *plan;
1515 Plan *subplan;
1516 List *in_operators;
1517 List *uniq_exprs;
1518 List *newtlist;
1519 int nextresno;
1520 bool newitems;
1521 int numGroupCols;
1522 AttrNumber *groupColIdx;
1523 Oid *groupCollations;
1524 int groupColPos;
1525 ListCell *l;
1526
1527 /* Unique doesn't project, so tlist requirements pass through */
1528 subplan = create_plan_recurse(root, best_path->subpath, flags);
1529
1530 /* Done if we don't need to do any actual unique-ifying */
1531 if (best_path->umethod == UNIQUE_PATH_NOOP)
1532 return subplan;
1533
1534 /*
1535 * As constructed, the subplan has a "flat" tlist containing just the Vars
1536 * needed here and at upper levels. The values we are supposed to
1537 * unique-ify may be expressions in these variables. We have to add any
1538 * such expressions to the subplan's tlist.
1539 *
1540 * The subplan may have a "physical" tlist if it is a simple scan plan. If
1541 * we're going to sort, this should be reduced to the regular tlist, so
1542 * that we don't sort more data than we need to. For hashing, the tlist
1543 * should be left as-is if we don't need to add any expressions; but if we
1544 * do have to add expressions, then a projection step will be needed at
1545 * runtime anyway, so we may as well remove unneeded items. Therefore
1546 * newtlist starts from build_path_tlist() not just a copy of the
1547 * subplan's tlist; and we don't install it into the subplan unless we are
1548 * sorting or stuff has to be added.
1549 */
1550 in_operators = best_path->in_operators;
1551 uniq_exprs = best_path->uniq_exprs;
1552
1553 /* initialize modified subplan tlist as just the "required" vars */
1554 newtlist = build_path_tlist(root, &best_path->path);
1555 nextresno = list_length(newtlist) + 1;
1556 newitems = false;
1557
1558 foreach(l, uniq_exprs)
1559 {
1560 Expr *uniqexpr = lfirst(l);
1561 TargetEntry *tle;
1562
1563 tle = tlist_member(uniqexpr, newtlist);
1564 if (!tle)
1565 {
1566 tle = makeTargetEntry((Expr *) uniqexpr,
1567 nextresno,
1568 NULL,
1569 false);
1570 newtlist = lappend(newtlist, tle);
1571 nextresno++;
1572 newitems = true;
1573 }
1574 }
1575
1576 /* Use change_plan_targetlist in case we need to insert a Result node */
1577 if (newitems || best_path->umethod == UNIQUE_PATH_SORT)
1578 subplan = change_plan_targetlist(subplan, newtlist,
1579 best_path->path.parallel_safe);
1580
1581 /*
1582 * Build control information showing which subplan output columns are to
1583 * be examined by the grouping step. Unfortunately we can't merge this
1584 * with the previous loop, since we didn't then know which version of the
1585 * subplan tlist we'd end up using.
1586 */
1587 newtlist = subplan->targetlist;
1588 numGroupCols = list_length(uniq_exprs);
1589 groupColIdx = (AttrNumber *) palloc(numGroupCols * sizeof(AttrNumber));
1590 groupCollations = (Oid *) palloc(numGroupCols * sizeof(Oid));
1591
1592 groupColPos = 0;
1593 foreach(l, uniq_exprs)
1594 {
1595 Expr *uniqexpr = lfirst(l);
1596 TargetEntry *tle;
1597
1598 tle = tlist_member(uniqexpr, newtlist);
1599 if (!tle) /* shouldn't happen */
1600 elog(ERROR, "failed to find unique expression in subplan tlist");
1601 groupColIdx[groupColPos] = tle->resno;
1602 groupCollations[groupColPos] = exprCollation((Node *) tle->expr);
1603 groupColPos++;
1604 }
1605
1606 if (best_path->umethod == UNIQUE_PATH_HASH)
1607 {
1608 Oid *groupOperators;
1609
1610 /*
1611 * Get the hashable equality operators for the Agg node to use.
1612 * Normally these are the same as the IN clause operators, but if
1613 * those are cross-type operators then the equality operators are the
1614 * ones for the IN clause operators' RHS datatype.
1615 */
1616 groupOperators = (Oid *) palloc(numGroupCols * sizeof(Oid));
1617 groupColPos = 0;
1618 foreach(l, in_operators)
1619 {
1620 Oid in_oper = lfirst_oid(l);
1621 Oid eq_oper;
1622
1623 if (!get_compatible_hash_operators(in_oper, NULL, &eq_oper))
1624 elog(ERROR, "could not find compatible hash operator for operator %u",
1625 in_oper);
1626 groupOperators[groupColPos++] = eq_oper;
1627 }
1628
1629 /*
1630 * Since the Agg node is going to project anyway, we can give it the
1631 * minimum output tlist, without any stuff we might have added to the
1632 * subplan tlist.
1633 */
1634 plan = (Plan *) make_agg(build_path_tlist(root, &best_path->path),
1635 NIL,
1636 AGG_HASHED,
1637 AGGSPLIT_SIMPLE,
1638 numGroupCols,
1639 groupColIdx,
1640 groupOperators,
1641 groupCollations,
1642 NIL,
1643 NIL,
1644 best_path->path.rows,
1645 subplan);
1646 }
1647 else
1648 {
1649 List *sortList = NIL;
1650 Sort *sort;
1651
1652 /* Create an ORDER BY list to sort the input compatibly */
1653 groupColPos = 0;
1654 foreach(l, in_operators)
1655 {
1656 Oid in_oper = lfirst_oid(l);
1657 Oid sortop;
1658 Oid eqop;
1659 TargetEntry *tle;
1660 SortGroupClause *sortcl;
1661
1662 sortop = get_ordering_op_for_equality_op(in_oper, false);
1663 if (!OidIsValid(sortop)) /* shouldn't happen */
1664 elog(ERROR, "could not find ordering operator for equality operator %u",
1665 in_oper);
1666
1667 /*
1668 * The Unique node will need equality operators. Normally these
1669 * are the same as the IN clause operators, but if those are
1670 * cross-type operators then the equality operators are the ones
1671 * for the IN clause operators' RHS datatype.
1672 */
1673 eqop = get_equality_op_for_ordering_op(sortop, NULL);
1674 if (!OidIsValid(eqop)) /* shouldn't happen */
1675 elog(ERROR, "could not find equality operator for ordering operator %u",
1676 sortop);
1677
1678 tle = get_tle_by_resno(subplan->targetlist,
1679 groupColIdx[groupColPos]);
1680 Assert(tle != NULL);
1681
1682 sortcl = makeNode(SortGroupClause);
1683 sortcl->tleSortGroupRef = assignSortGroupRef(tle,
1684 subplan->targetlist);
1685 sortcl->eqop = eqop;
1686 sortcl->sortop = sortop;
1687 sortcl->nulls_first = false;
1688 sortcl->hashable = false; /* no need to make this accurate */
1689 sortList = lappend(sortList, sortcl);
1690 groupColPos++;
1691 }
1692 sort = make_sort_from_sortclauses(sortList, subplan);
1693 label_sort_with_costsize(root, sort, -1.0);
1694 plan = (Plan *) make_unique_from_sortclauses((Plan *) sort, sortList);
1695 }
1696
1697 /* Copy cost data from Path to Plan */
1698 copy_generic_path_info(plan, &best_path->path);
1699
1700 return plan;
1701 }
1702
1703 /*
1704 * create_gather_plan
1705 *
1706 * Create a Gather plan for 'best_path' and (recursively) plans
1707 * for its subpaths.
1708 */
1709 static Gather *
create_gather_plan(PlannerInfo * root,GatherPath * best_path)1710 create_gather_plan(PlannerInfo *root, GatherPath *best_path)
1711 {
1712 Gather *gather_plan;
1713 Plan *subplan;
1714 List *tlist;
1715
1716 /*
1717 * Although the Gather node can project, we prefer to push down such work
1718 * to its child node, so demand an exact tlist from the child.
1719 */
1720 subplan = create_plan_recurse(root, best_path->subpath, CP_EXACT_TLIST);
1721
1722 tlist = build_path_tlist(root, &best_path->path);
1723
1724 gather_plan = make_gather(tlist,
1725 NIL,
1726 best_path->num_workers,
1727 assign_special_exec_param(root),
1728 best_path->single_copy,
1729 subplan);
1730
1731 copy_generic_path_info(&gather_plan->plan, &best_path->path);
1732
1733 /* use parallel mode for parallel plans. */
1734 root->glob->parallelModeNeeded = true;
1735
1736 return gather_plan;
1737 }
1738
1739 /*
1740 * create_gather_merge_plan
1741 *
1742 * Create a Gather Merge plan for 'best_path' and (recursively)
1743 * plans for its subpaths.
1744 */
1745 static GatherMerge *
create_gather_merge_plan(PlannerInfo * root,GatherMergePath * best_path)1746 create_gather_merge_plan(PlannerInfo *root, GatherMergePath *best_path)
1747 {
1748 GatherMerge *gm_plan;
1749 Plan *subplan;
1750 List *pathkeys = best_path->path.pathkeys;
1751 List *tlist = build_path_tlist(root, &best_path->path);
1752
1753 /* As with Gather, it's best to project away columns in the workers. */
1754 subplan = create_plan_recurse(root, best_path->subpath, CP_EXACT_TLIST);
1755
1756 /* Create a shell for a GatherMerge plan. */
1757 gm_plan = makeNode(GatherMerge);
1758 gm_plan->plan.targetlist = tlist;
1759 gm_plan->num_workers = best_path->num_workers;
1760 copy_generic_path_info(&gm_plan->plan, &best_path->path);
1761
1762 /* Assign the rescan Param. */
1763 gm_plan->rescan_param = assign_special_exec_param(root);
1764
1765 /* Gather Merge is pointless with no pathkeys; use Gather instead. */
1766 Assert(pathkeys != NIL);
1767
1768 /* Compute sort column info, and adjust subplan's tlist as needed */
1769 subplan = prepare_sort_from_pathkeys(subplan, pathkeys,
1770 best_path->subpath->parent->relids,
1771 gm_plan->sortColIdx,
1772 false,
1773 &gm_plan->numCols,
1774 &gm_plan->sortColIdx,
1775 &gm_plan->sortOperators,
1776 &gm_plan->collations,
1777 &gm_plan->nullsFirst);
1778
1779
1780 /* Now, insert a Sort node if subplan isn't sufficiently ordered */
1781 if (!pathkeys_contained_in(pathkeys, best_path->subpath->pathkeys))
1782 subplan = (Plan *) make_sort(subplan, gm_plan->numCols,
1783 gm_plan->sortColIdx,
1784 gm_plan->sortOperators,
1785 gm_plan->collations,
1786 gm_plan->nullsFirst);
1787
1788 /* Now insert the subplan under GatherMerge. */
1789 gm_plan->plan.lefttree = subplan;
1790
1791 /* use parallel mode for parallel plans. */
1792 root->glob->parallelModeNeeded = true;
1793
1794 return gm_plan;
1795 }
1796
1797 /*
1798 * create_projection_plan
1799 *
1800 * Create a plan tree to do a projection step and (recursively) plans
1801 * for its subpaths. We may need a Result node for the projection,
1802 * but sometimes we can just let the subplan do the work.
1803 */
1804 static Plan *
create_projection_plan(PlannerInfo * root,ProjectionPath * best_path,int flags)1805 create_projection_plan(PlannerInfo *root, ProjectionPath *best_path, int flags)
1806 {
1807 Plan *plan;
1808 Plan *subplan;
1809 List *tlist;
1810 bool needs_result_node = false;
1811
1812 /*
1813 * Convert our subpath to a Plan and determine whether we need a Result
1814 * node.
1815 *
1816 * In most cases where we don't need to project, creation_projection_path
1817 * will have set dummypp, but not always. First, some createplan.c
1818 * routines change the tlists of their nodes. (An example is that
1819 * create_merge_append_plan might add resjunk sort columns to a
1820 * MergeAppend.) Second, create_projection_path has no way of knowing
1821 * what path node will be placed on top of the projection path and
1822 * therefore can't predict whether it will require an exact tlist. For
1823 * both of these reasons, we have to recheck here.
1824 */
1825 if (use_physical_tlist(root, &best_path->path, flags))
1826 {
1827 /*
1828 * Our caller doesn't really care what tlist we return, so we don't
1829 * actually need to project. However, we may still need to ensure
1830 * proper sortgroupref labels, if the caller cares about those.
1831 */
1832 subplan = create_plan_recurse(root, best_path->subpath, 0);
1833 tlist = subplan->targetlist;
1834 if (flags & CP_LABEL_TLIST)
1835 apply_pathtarget_labeling_to_tlist(tlist,
1836 best_path->path.pathtarget);
1837 }
1838 else if (is_projection_capable_path(best_path->subpath))
1839 {
1840 /*
1841 * Our caller requires that we return the exact tlist, but no separate
1842 * result node is needed because the subpath is projection-capable.
1843 * Tell create_plan_recurse that we're going to ignore the tlist it
1844 * produces.
1845 */
1846 subplan = create_plan_recurse(root, best_path->subpath,
1847 CP_IGNORE_TLIST);
1848 Assert(is_projection_capable_plan(subplan));
1849 tlist = build_path_tlist(root, &best_path->path);
1850 }
1851 else
1852 {
1853 /*
1854 * It looks like we need a result node, unless by good fortune the
1855 * requested tlist is exactly the one the child wants to produce.
1856 */
1857 subplan = create_plan_recurse(root, best_path->subpath, 0);
1858 tlist = build_path_tlist(root, &best_path->path);
1859 needs_result_node = !tlist_same_exprs(tlist, subplan->targetlist);
1860 }
1861
1862 /*
1863 * If we make a different decision about whether to include a Result node
1864 * than create_projection_path did, we'll have made slightly wrong cost
1865 * estimates; but label the plan with the cost estimates we actually used,
1866 * not "corrected" ones. (XXX this could be cleaned up if we moved more
1867 * of the sortcolumn setup logic into Path creation, but that would add
1868 * expense to creating Paths we might end up not using.)
1869 */
1870 if (!needs_result_node)
1871 {
1872 /* Don't need a separate Result, just assign tlist to subplan */
1873 plan = subplan;
1874 plan->targetlist = tlist;
1875
1876 /* Label plan with the estimated costs we actually used */
1877 plan->startup_cost = best_path->path.startup_cost;
1878 plan->total_cost = best_path->path.total_cost;
1879 plan->plan_rows = best_path->path.rows;
1880 plan->plan_width = best_path->path.pathtarget->width;
1881 plan->parallel_safe = best_path->path.parallel_safe;
1882 /* ... but don't change subplan's parallel_aware flag */
1883 }
1884 else
1885 {
1886 /* We need a Result node */
1887 plan = (Plan *) make_result(tlist, NULL, subplan);
1888
1889 copy_generic_path_info(plan, (Path *) best_path);
1890 }
1891
1892 return plan;
1893 }
1894
1895 /*
1896 * inject_projection_plan
1897 * Insert a Result node to do a projection step.
1898 *
1899 * This is used in a few places where we decide on-the-fly that we need a
1900 * projection step as part of the tree generated for some Path node.
1901 * We should try to get rid of this in favor of doing it more honestly.
1902 *
1903 * One reason it's ugly is we have to be told the right parallel_safe marking
1904 * to apply (since the tlist might be unsafe even if the child plan is safe).
1905 */
1906 static Plan *
inject_projection_plan(Plan * subplan,List * tlist,bool parallel_safe)1907 inject_projection_plan(Plan *subplan, List *tlist, bool parallel_safe)
1908 {
1909 Plan *plan;
1910
1911 plan = (Plan *) make_result(tlist, NULL, subplan);
1912
1913 /*
1914 * In principle, we should charge tlist eval cost plus cpu_per_tuple per
1915 * row for the Result node. But the former has probably been factored in
1916 * already and the latter was not accounted for during Path construction,
1917 * so being formally correct might just make the EXPLAIN output look less
1918 * consistent not more so. Hence, just copy the subplan's cost.
1919 */
1920 copy_plan_costsize(plan, subplan);
1921 plan->parallel_safe = parallel_safe;
1922
1923 return plan;
1924 }
1925
1926 /*
1927 * change_plan_targetlist
1928 * Externally available wrapper for inject_projection_plan.
1929 *
1930 * This is meant for use by FDW plan-generation functions, which might
1931 * want to adjust the tlist computed by some subplan tree. In general,
1932 * a Result node is needed to compute the new tlist, but we can optimize
1933 * some cases.
1934 *
1935 * In most cases, tlist_parallel_safe can just be passed as the parallel_safe
1936 * flag of the FDW's own Path node.
1937 */
1938 Plan *
change_plan_targetlist(Plan * subplan,List * tlist,bool tlist_parallel_safe)1939 change_plan_targetlist(Plan *subplan, List *tlist, bool tlist_parallel_safe)
1940 {
1941 /*
1942 * If the top plan node can't do projections and its existing target list
1943 * isn't already what we need, we need to add a Result node to help it
1944 * along.
1945 */
1946 if (!is_projection_capable_plan(subplan) &&
1947 !tlist_same_exprs(tlist, subplan->targetlist))
1948 subplan = inject_projection_plan(subplan, tlist,
1949 subplan->parallel_safe &&
1950 tlist_parallel_safe);
1951 else
1952 {
1953 /* Else we can just replace the plan node's tlist */
1954 subplan->targetlist = tlist;
1955 subplan->parallel_safe &= tlist_parallel_safe;
1956 }
1957 return subplan;
1958 }
1959
1960 /*
1961 * create_sort_plan
1962 *
1963 * Create a Sort plan for 'best_path' and (recursively) plans
1964 * for its subpaths.
1965 */
1966 static Sort *
create_sort_plan(PlannerInfo * root,SortPath * best_path,int flags)1967 create_sort_plan(PlannerInfo *root, SortPath *best_path, int flags)
1968 {
1969 Sort *plan;
1970 Plan *subplan;
1971
1972 /*
1973 * We don't want any excess columns in the sorted tuples, so request a
1974 * smaller tlist. Otherwise, since Sort doesn't project, tlist
1975 * requirements pass through.
1976 */
1977 subplan = create_plan_recurse(root, best_path->subpath,
1978 flags | CP_SMALL_TLIST);
1979
1980 /*
1981 * make_sort_from_pathkeys() indirectly calls find_ec_member_for_tle(),
1982 * which will ignore any child EC members that don't belong to the given
1983 * relids. Thus, if this sort path is based on a child relation, we must
1984 * pass its relids.
1985 */
1986 plan = make_sort_from_pathkeys(subplan, best_path->path.pathkeys,
1987 IS_OTHER_REL(best_path->subpath->parent) ?
1988 best_path->path.parent->relids : NULL);
1989
1990 copy_generic_path_info(&plan->plan, (Path *) best_path);
1991
1992 return plan;
1993 }
1994
1995 /*
1996 * create_group_plan
1997 *
1998 * Create a Group plan for 'best_path' and (recursively) plans
1999 * for its subpaths.
2000 */
2001 static Group *
create_group_plan(PlannerInfo * root,GroupPath * best_path)2002 create_group_plan(PlannerInfo *root, GroupPath *best_path)
2003 {
2004 Group *plan;
2005 Plan *subplan;
2006 List *tlist;
2007 List *quals;
2008
2009 /*
2010 * Group can project, so no need to be terribly picky about child tlist,
2011 * but we do need grouping columns to be available
2012 */
2013 subplan = create_plan_recurse(root, best_path->subpath, CP_LABEL_TLIST);
2014
2015 tlist = build_path_tlist(root, &best_path->path);
2016
2017 quals = order_qual_clauses(root, best_path->qual);
2018
2019 plan = make_group(tlist,
2020 quals,
2021 list_length(best_path->groupClause),
2022 extract_grouping_cols(best_path->groupClause,
2023 subplan->targetlist),
2024 extract_grouping_ops(best_path->groupClause),
2025 extract_grouping_collations(best_path->groupClause,
2026 subplan->targetlist),
2027 subplan);
2028
2029 copy_generic_path_info(&plan->plan, (Path *) best_path);
2030
2031 return plan;
2032 }
2033
2034 /*
2035 * create_upper_unique_plan
2036 *
2037 * Create a Unique plan for 'best_path' and (recursively) plans
2038 * for its subpaths.
2039 */
2040 static Unique *
create_upper_unique_plan(PlannerInfo * root,UpperUniquePath * best_path,int flags)2041 create_upper_unique_plan(PlannerInfo *root, UpperUniquePath *best_path, int flags)
2042 {
2043 Unique *plan;
2044 Plan *subplan;
2045
2046 /*
2047 * Unique doesn't project, so tlist requirements pass through; moreover we
2048 * need grouping columns to be labeled.
2049 */
2050 subplan = create_plan_recurse(root, best_path->subpath,
2051 flags | CP_LABEL_TLIST);
2052
2053 plan = make_unique_from_pathkeys(subplan,
2054 best_path->path.pathkeys,
2055 best_path->numkeys);
2056
2057 copy_generic_path_info(&plan->plan, (Path *) best_path);
2058
2059 return plan;
2060 }
2061
2062 /*
2063 * create_agg_plan
2064 *
2065 * Create an Agg plan for 'best_path' and (recursively) plans
2066 * for its subpaths.
2067 */
2068 static Agg *
create_agg_plan(PlannerInfo * root,AggPath * best_path)2069 create_agg_plan(PlannerInfo *root, AggPath *best_path)
2070 {
2071 Agg *plan;
2072 Plan *subplan;
2073 List *tlist;
2074 List *quals;
2075
2076 /*
2077 * Agg can project, so no need to be terribly picky about child tlist, but
2078 * we do need grouping columns to be available
2079 */
2080 subplan = create_plan_recurse(root, best_path->subpath, CP_LABEL_TLIST);
2081
2082 tlist = build_path_tlist(root, &best_path->path);
2083
2084 quals = order_qual_clauses(root, best_path->qual);
2085
2086 plan = make_agg(tlist, quals,
2087 best_path->aggstrategy,
2088 best_path->aggsplit,
2089 list_length(best_path->groupClause),
2090 extract_grouping_cols(best_path->groupClause,
2091 subplan->targetlist),
2092 extract_grouping_ops(best_path->groupClause),
2093 extract_grouping_collations(best_path->groupClause,
2094 subplan->targetlist),
2095 NIL,
2096 NIL,
2097 best_path->numGroups,
2098 subplan);
2099
2100 copy_generic_path_info(&plan->plan, (Path *) best_path);
2101
2102 return plan;
2103 }
2104
2105 /*
2106 * Given a groupclause for a collection of grouping sets, produce the
2107 * corresponding groupColIdx.
2108 *
2109 * root->grouping_map maps the tleSortGroupRef to the actual column position in
2110 * the input tuple. So we get the ref from the entries in the groupclause and
2111 * look them up there.
2112 */
2113 static AttrNumber *
remap_groupColIdx(PlannerInfo * root,List * groupClause)2114 remap_groupColIdx(PlannerInfo *root, List *groupClause)
2115 {
2116 AttrNumber *grouping_map = root->grouping_map;
2117 AttrNumber *new_grpColIdx;
2118 ListCell *lc;
2119 int i;
2120
2121 Assert(grouping_map);
2122
2123 new_grpColIdx = palloc0(sizeof(AttrNumber) * list_length(groupClause));
2124
2125 i = 0;
2126 foreach(lc, groupClause)
2127 {
2128 SortGroupClause *clause = lfirst(lc);
2129
2130 new_grpColIdx[i++] = grouping_map[clause->tleSortGroupRef];
2131 }
2132
2133 return new_grpColIdx;
2134 }
2135
2136 /*
2137 * create_groupingsets_plan
2138 * Create a plan for 'best_path' and (recursively) plans
2139 * for its subpaths.
2140 *
2141 * What we emit is an Agg plan with some vestigial Agg and Sort nodes
2142 * hanging off the side. The top Agg implements the last grouping set
2143 * specified in the GroupingSetsPath, and any additional grouping sets
2144 * each give rise to a subsidiary Agg and Sort node in the top Agg's
2145 * "chain" list. These nodes don't participate in the plan directly,
2146 * but they are a convenient way to represent the required data for
2147 * the extra steps.
2148 *
2149 * Returns a Plan node.
2150 */
2151 static Plan *
create_groupingsets_plan(PlannerInfo * root,GroupingSetsPath * best_path)2152 create_groupingsets_plan(PlannerInfo *root, GroupingSetsPath *best_path)
2153 {
2154 Agg *plan;
2155 Plan *subplan;
2156 List *rollups = best_path->rollups;
2157 AttrNumber *grouping_map;
2158 int maxref;
2159 List *chain;
2160 ListCell *lc;
2161
2162 /* Shouldn't get here without grouping sets */
2163 Assert(root->parse->groupingSets);
2164 Assert(rollups != NIL);
2165
2166 /*
2167 * Agg can project, so no need to be terribly picky about child tlist, but
2168 * we do need grouping columns to be available
2169 */
2170 subplan = create_plan_recurse(root, best_path->subpath, CP_LABEL_TLIST);
2171
2172 /*
2173 * Compute the mapping from tleSortGroupRef to column index in the child's
2174 * tlist. First, identify max SortGroupRef in groupClause, for array
2175 * sizing.
2176 */
2177 maxref = 0;
2178 foreach(lc, root->parse->groupClause)
2179 {
2180 SortGroupClause *gc = (SortGroupClause *) lfirst(lc);
2181
2182 if (gc->tleSortGroupRef > maxref)
2183 maxref = gc->tleSortGroupRef;
2184 }
2185
2186 grouping_map = (AttrNumber *) palloc0((maxref + 1) * sizeof(AttrNumber));
2187
2188 /* Now look up the column numbers in the child's tlist */
2189 foreach(lc, root->parse->groupClause)
2190 {
2191 SortGroupClause *gc = (SortGroupClause *) lfirst(lc);
2192 TargetEntry *tle = get_sortgroupclause_tle(gc, subplan->targetlist);
2193
2194 grouping_map[gc->tleSortGroupRef] = tle->resno;
2195 }
2196
2197 /*
2198 * During setrefs.c, we'll need the grouping_map to fix up the cols lists
2199 * in GroupingFunc nodes. Save it for setrefs.c to use.
2200 *
2201 * This doesn't work if we're in an inheritance subtree (see notes in
2202 * create_modifytable_plan). Fortunately we can't be because there would
2203 * never be grouping in an UPDATE/DELETE; but let's Assert that.
2204 */
2205 Assert(root->inhTargetKind == INHKIND_NONE);
2206 Assert(root->grouping_map == NULL);
2207 root->grouping_map = grouping_map;
2208
2209 /*
2210 * Generate the side nodes that describe the other sort and group
2211 * operations besides the top one. Note that we don't worry about putting
2212 * accurate cost estimates in the side nodes; only the topmost Agg node's
2213 * costs will be shown by EXPLAIN.
2214 */
2215 chain = NIL;
2216 if (list_length(rollups) > 1)
2217 {
2218 ListCell *lc2 = lnext(list_head(rollups));
2219 bool is_first_sort = ((RollupData *) linitial(rollups))->is_hashed;
2220
2221 for_each_cell(lc, lc2)
2222 {
2223 RollupData *rollup = lfirst(lc);
2224 AttrNumber *new_grpColIdx;
2225 Plan *sort_plan = NULL;
2226 Plan *agg_plan;
2227 AggStrategy strat;
2228
2229 new_grpColIdx = remap_groupColIdx(root, rollup->groupClause);
2230
2231 if (!rollup->is_hashed && !is_first_sort)
2232 {
2233 sort_plan = (Plan *)
2234 make_sort_from_groupcols(rollup->groupClause,
2235 new_grpColIdx,
2236 subplan);
2237 }
2238
2239 if (!rollup->is_hashed)
2240 is_first_sort = false;
2241
2242 if (rollup->is_hashed)
2243 strat = AGG_HASHED;
2244 else if (list_length(linitial(rollup->gsets)) == 0)
2245 strat = AGG_PLAIN;
2246 else
2247 strat = AGG_SORTED;
2248
2249 agg_plan = (Plan *) make_agg(NIL,
2250 NIL,
2251 strat,
2252 AGGSPLIT_SIMPLE,
2253 list_length((List *) linitial(rollup->gsets)),
2254 new_grpColIdx,
2255 extract_grouping_ops(rollup->groupClause),
2256 extract_grouping_collations(rollup->groupClause, subplan->targetlist),
2257 rollup->gsets,
2258 NIL,
2259 rollup->numGroups,
2260 sort_plan);
2261
2262 /*
2263 * Remove stuff we don't need to avoid bloating debug output.
2264 */
2265 if (sort_plan)
2266 {
2267 sort_plan->targetlist = NIL;
2268 sort_plan->lefttree = NULL;
2269 }
2270
2271 chain = lappend(chain, agg_plan);
2272 }
2273 }
2274
2275 /*
2276 * Now make the real Agg node
2277 */
2278 {
2279 RollupData *rollup = linitial(rollups);
2280 AttrNumber *top_grpColIdx;
2281 int numGroupCols;
2282
2283 top_grpColIdx = remap_groupColIdx(root, rollup->groupClause);
2284
2285 numGroupCols = list_length((List *) linitial(rollup->gsets));
2286
2287 plan = make_agg(build_path_tlist(root, &best_path->path),
2288 best_path->qual,
2289 best_path->aggstrategy,
2290 AGGSPLIT_SIMPLE,
2291 numGroupCols,
2292 top_grpColIdx,
2293 extract_grouping_ops(rollup->groupClause),
2294 extract_grouping_collations(rollup->groupClause, subplan->targetlist),
2295 rollup->gsets,
2296 chain,
2297 rollup->numGroups,
2298 subplan);
2299
2300 /* Copy cost data from Path to Plan */
2301 copy_generic_path_info(&plan->plan, &best_path->path);
2302 }
2303
2304 return (Plan *) plan;
2305 }
2306
2307 /*
2308 * create_minmaxagg_plan
2309 *
2310 * Create a Result plan for 'best_path' and (recursively) plans
2311 * for its subpaths.
2312 */
2313 static Result *
create_minmaxagg_plan(PlannerInfo * root,MinMaxAggPath * best_path)2314 create_minmaxagg_plan(PlannerInfo *root, MinMaxAggPath *best_path)
2315 {
2316 Result *plan;
2317 List *tlist;
2318 ListCell *lc;
2319
2320 /* Prepare an InitPlan for each aggregate's subquery. */
2321 foreach(lc, best_path->mmaggregates)
2322 {
2323 MinMaxAggInfo *mminfo = (MinMaxAggInfo *) lfirst(lc);
2324 PlannerInfo *subroot = mminfo->subroot;
2325 Query *subparse = subroot->parse;
2326 Plan *plan;
2327
2328 /*
2329 * Generate the plan for the subquery. We already have a Path, but we
2330 * have to convert it to a Plan and attach a LIMIT node above it.
2331 * Since we are entering a different planner context (subroot),
2332 * recurse to create_plan not create_plan_recurse.
2333 */
2334 plan = create_plan(subroot, mminfo->path);
2335
2336 plan = (Plan *) make_limit(plan,
2337 subparse->limitOffset,
2338 subparse->limitCount);
2339
2340 /* Must apply correct cost/width data to Limit node */
2341 plan->startup_cost = mminfo->path->startup_cost;
2342 plan->total_cost = mminfo->pathcost;
2343 plan->plan_rows = 1;
2344 plan->plan_width = mminfo->path->pathtarget->width;
2345 plan->parallel_aware = false;
2346 plan->parallel_safe = mminfo->path->parallel_safe;
2347
2348 /* Convert the plan into an InitPlan in the outer query. */
2349 SS_make_initplan_from_plan(root, subroot, plan, mminfo->param);
2350 }
2351
2352 /* Generate the output plan --- basically just a Result */
2353 tlist = build_path_tlist(root, &best_path->path);
2354
2355 plan = make_result(tlist, (Node *) best_path->quals, NULL);
2356
2357 copy_generic_path_info(&plan->plan, (Path *) best_path);
2358
2359 /*
2360 * During setrefs.c, we'll need to replace references to the Agg nodes
2361 * with InitPlan output params. (We can't just do that locally in the
2362 * MinMaxAgg node, because path nodes above here may have Agg references
2363 * as well.) Save the mmaggregates list to tell setrefs.c to do that.
2364 *
2365 * This doesn't work if we're in an inheritance subtree (see notes in
2366 * create_modifytable_plan). Fortunately we can't be because there would
2367 * never be aggregates in an UPDATE/DELETE; but let's Assert that.
2368 */
2369 Assert(root->inhTargetKind == INHKIND_NONE);
2370 Assert(root->minmax_aggs == NIL);
2371 root->minmax_aggs = best_path->mmaggregates;
2372
2373 return plan;
2374 }
2375
2376 /*
2377 * create_windowagg_plan
2378 *
2379 * Create a WindowAgg plan for 'best_path' and (recursively) plans
2380 * for its subpaths.
2381 */
2382 static WindowAgg *
create_windowagg_plan(PlannerInfo * root,WindowAggPath * best_path)2383 create_windowagg_plan(PlannerInfo *root, WindowAggPath *best_path)
2384 {
2385 WindowAgg *plan;
2386 WindowClause *wc = best_path->winclause;
2387 int numPart = list_length(wc->partitionClause);
2388 int numOrder = list_length(wc->orderClause);
2389 Plan *subplan;
2390 List *tlist;
2391 int partNumCols;
2392 AttrNumber *partColIdx;
2393 Oid *partOperators;
2394 Oid *partCollations;
2395 int ordNumCols;
2396 AttrNumber *ordColIdx;
2397 Oid *ordOperators;
2398 Oid *ordCollations;
2399 ListCell *lc;
2400
2401 /*
2402 * Choice of tlist here is motivated by the fact that WindowAgg will be
2403 * storing the input rows of window frames in a tuplestore; it therefore
2404 * behooves us to request a small tlist to avoid wasting space. We do of
2405 * course need grouping columns to be available.
2406 */
2407 subplan = create_plan_recurse(root, best_path->subpath,
2408 CP_LABEL_TLIST | CP_SMALL_TLIST);
2409
2410 tlist = build_path_tlist(root, &best_path->path);
2411
2412 /*
2413 * Convert SortGroupClause lists into arrays of attr indexes and equality
2414 * operators, as wanted by executor. (Note: in principle, it's possible
2415 * to drop some of the sort columns, if they were proved redundant by
2416 * pathkey logic. However, it doesn't seem worth going out of our way to
2417 * optimize such cases. In any case, we must *not* remove the ordering
2418 * column for RANGE OFFSET cases, as the executor needs that for in_range
2419 * tests even if it's known to be equal to some partitioning column.)
2420 */
2421 partColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numPart);
2422 partOperators = (Oid *) palloc(sizeof(Oid) * numPart);
2423 partCollations = (Oid *) palloc(sizeof(Oid) * numPart);
2424
2425 partNumCols = 0;
2426 foreach(lc, wc->partitionClause)
2427 {
2428 SortGroupClause *sgc = (SortGroupClause *) lfirst(lc);
2429 TargetEntry *tle = get_sortgroupclause_tle(sgc, subplan->targetlist);
2430
2431 Assert(OidIsValid(sgc->eqop));
2432 partColIdx[partNumCols] = tle->resno;
2433 partOperators[partNumCols] = sgc->eqop;
2434 partCollations[partNumCols] = exprCollation((Node *) tle->expr);
2435 partNumCols++;
2436 }
2437
2438 ordColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numOrder);
2439 ordOperators = (Oid *) palloc(sizeof(Oid) * numOrder);
2440 ordCollations = (Oid *) palloc(sizeof(Oid) * numOrder);
2441
2442 ordNumCols = 0;
2443 foreach(lc, wc->orderClause)
2444 {
2445 SortGroupClause *sgc = (SortGroupClause *) lfirst(lc);
2446 TargetEntry *tle = get_sortgroupclause_tle(sgc, subplan->targetlist);
2447
2448 Assert(OidIsValid(sgc->eqop));
2449 ordColIdx[ordNumCols] = tle->resno;
2450 ordOperators[ordNumCols] = sgc->eqop;
2451 ordCollations[ordNumCols] = exprCollation((Node *) tle->expr);
2452 ordNumCols++;
2453 }
2454
2455 /* And finally we can make the WindowAgg node */
2456 plan = make_windowagg(tlist,
2457 wc->winref,
2458 partNumCols,
2459 partColIdx,
2460 partOperators,
2461 partCollations,
2462 ordNumCols,
2463 ordColIdx,
2464 ordOperators,
2465 ordCollations,
2466 wc->frameOptions,
2467 wc->startOffset,
2468 wc->endOffset,
2469 wc->startInRangeFunc,
2470 wc->endInRangeFunc,
2471 wc->inRangeColl,
2472 wc->inRangeAsc,
2473 wc->inRangeNullsFirst,
2474 subplan);
2475
2476 copy_generic_path_info(&plan->plan, (Path *) best_path);
2477
2478 return plan;
2479 }
2480
2481 /*
2482 * create_setop_plan
2483 *
2484 * Create a SetOp plan for 'best_path' and (recursively) plans
2485 * for its subpaths.
2486 */
2487 static SetOp *
create_setop_plan(PlannerInfo * root,SetOpPath * best_path,int flags)2488 create_setop_plan(PlannerInfo *root, SetOpPath *best_path, int flags)
2489 {
2490 SetOp *plan;
2491 Plan *subplan;
2492 long numGroups;
2493
2494 /*
2495 * SetOp doesn't project, so tlist requirements pass through; moreover we
2496 * need grouping columns to be labeled.
2497 */
2498 subplan = create_plan_recurse(root, best_path->subpath,
2499 flags | CP_LABEL_TLIST);
2500
2501 /* Convert numGroups to long int --- but 'ware overflow! */
2502 numGroups = (long) Min(best_path->numGroups, (double) LONG_MAX);
2503
2504 plan = make_setop(best_path->cmd,
2505 best_path->strategy,
2506 subplan,
2507 best_path->distinctList,
2508 best_path->flagColIdx,
2509 best_path->firstFlag,
2510 numGroups);
2511
2512 copy_generic_path_info(&plan->plan, (Path *) best_path);
2513
2514 return plan;
2515 }
2516
2517 /*
2518 * create_recursiveunion_plan
2519 *
2520 * Create a RecursiveUnion plan for 'best_path' and (recursively) plans
2521 * for its subpaths.
2522 */
2523 static RecursiveUnion *
create_recursiveunion_plan(PlannerInfo * root,RecursiveUnionPath * best_path)2524 create_recursiveunion_plan(PlannerInfo *root, RecursiveUnionPath *best_path)
2525 {
2526 RecursiveUnion *plan;
2527 Plan *leftplan;
2528 Plan *rightplan;
2529 List *tlist;
2530 long numGroups;
2531
2532 /* Need both children to produce same tlist, so force it */
2533 leftplan = create_plan_recurse(root, best_path->leftpath, CP_EXACT_TLIST);
2534 rightplan = create_plan_recurse(root, best_path->rightpath, CP_EXACT_TLIST);
2535
2536 tlist = build_path_tlist(root, &best_path->path);
2537
2538 /* Convert numGroups to long int --- but 'ware overflow! */
2539 numGroups = (long) Min(best_path->numGroups, (double) LONG_MAX);
2540
2541 plan = make_recursive_union(tlist,
2542 leftplan,
2543 rightplan,
2544 best_path->wtParam,
2545 best_path->distinctList,
2546 numGroups);
2547
2548 copy_generic_path_info(&plan->plan, (Path *) best_path);
2549
2550 return plan;
2551 }
2552
2553 /*
2554 * create_lockrows_plan
2555 *
2556 * Create a LockRows plan for 'best_path' and (recursively) plans
2557 * for its subpaths.
2558 */
2559 static LockRows *
create_lockrows_plan(PlannerInfo * root,LockRowsPath * best_path,int flags)2560 create_lockrows_plan(PlannerInfo *root, LockRowsPath *best_path,
2561 int flags)
2562 {
2563 LockRows *plan;
2564 Plan *subplan;
2565
2566 /* LockRows doesn't project, so tlist requirements pass through */
2567 subplan = create_plan_recurse(root, best_path->subpath, flags);
2568
2569 plan = make_lockrows(subplan, best_path->rowMarks, best_path->epqParam);
2570
2571 copy_generic_path_info(&plan->plan, (Path *) best_path);
2572
2573 return plan;
2574 }
2575
2576 /*
2577 * create_modifytable_plan
2578 * Create a ModifyTable plan for 'best_path'.
2579 *
2580 * Returns a Plan node.
2581 */
2582 static ModifyTable *
create_modifytable_plan(PlannerInfo * root,ModifyTablePath * best_path)2583 create_modifytable_plan(PlannerInfo *root, ModifyTablePath *best_path)
2584 {
2585 ModifyTable *plan;
2586 List *subplans = NIL;
2587 ListCell *subpaths,
2588 *subroots;
2589
2590 /* Build the plan for each input path */
2591 forboth(subpaths, best_path->subpaths,
2592 subroots, best_path->subroots)
2593 {
2594 Path *subpath = (Path *) lfirst(subpaths);
2595 PlannerInfo *subroot = (PlannerInfo *) lfirst(subroots);
2596 Plan *subplan;
2597
2598 /*
2599 * In an inherited UPDATE/DELETE, reference the per-child modified
2600 * subroot while creating Plans from Paths for the child rel. This is
2601 * a kluge, but otherwise it's too hard to ensure that Plan creation
2602 * functions (particularly in FDWs) don't depend on the contents of
2603 * "root" matching what they saw at Path creation time. The main
2604 * downside is that creation functions for Plans that might appear
2605 * below a ModifyTable cannot expect to modify the contents of "root"
2606 * and have it "stick" for subsequent processing such as setrefs.c.
2607 * That's not great, but it seems better than the alternative.
2608 */
2609 subplan = create_plan_recurse(subroot, subpath, CP_EXACT_TLIST);
2610
2611 /* Transfer resname/resjunk labeling, too, to keep executor happy */
2612 apply_tlist_labeling(subplan->targetlist, subroot->processed_tlist);
2613
2614 subplans = lappend(subplans, subplan);
2615 }
2616
2617 plan = make_modifytable(root,
2618 best_path->operation,
2619 best_path->canSetTag,
2620 best_path->nominalRelation,
2621 best_path->rootRelation,
2622 best_path->partColsUpdated,
2623 best_path->resultRelations,
2624 subplans,
2625 best_path->subroots,
2626 best_path->withCheckOptionLists,
2627 best_path->returningLists,
2628 best_path->rowMarks,
2629 best_path->onconflict,
2630 best_path->epqParam);
2631
2632 copy_generic_path_info(&plan->plan, &best_path->path);
2633
2634 return plan;
2635 }
2636
2637 /*
2638 * create_limit_plan
2639 *
2640 * Create a Limit plan for 'best_path' and (recursively) plans
2641 * for its subpaths.
2642 */
2643 static Limit *
create_limit_plan(PlannerInfo * root,LimitPath * best_path,int flags)2644 create_limit_plan(PlannerInfo *root, LimitPath *best_path, int flags)
2645 {
2646 Limit *plan;
2647 Plan *subplan;
2648
2649 /* Limit doesn't project, so tlist requirements pass through */
2650 subplan = create_plan_recurse(root, best_path->subpath, flags);
2651
2652 plan = make_limit(subplan,
2653 best_path->limitOffset,
2654 best_path->limitCount);
2655
2656 copy_generic_path_info(&plan->plan, (Path *) best_path);
2657
2658 return plan;
2659 }
2660
2661
2662 /*****************************************************************************
2663 *
2664 * BASE-RELATION SCAN METHODS
2665 *
2666 *****************************************************************************/
2667
2668
2669 /*
2670 * create_seqscan_plan
2671 * Returns a seqscan plan for the base relation scanned by 'best_path'
2672 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
2673 */
2674 static SeqScan *
create_seqscan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)2675 create_seqscan_plan(PlannerInfo *root, Path *best_path,
2676 List *tlist, List *scan_clauses)
2677 {
2678 SeqScan *scan_plan;
2679 Index scan_relid = best_path->parent->relid;
2680
2681 /* it should be a base rel... */
2682 Assert(scan_relid > 0);
2683 Assert(best_path->parent->rtekind == RTE_RELATION);
2684
2685 /* Sort clauses into best execution order */
2686 scan_clauses = order_qual_clauses(root, scan_clauses);
2687
2688 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
2689 scan_clauses = extract_actual_clauses(scan_clauses, false);
2690
2691 /* Replace any outer-relation variables with nestloop params */
2692 if (best_path->param_info)
2693 {
2694 scan_clauses = (List *)
2695 replace_nestloop_params(root, (Node *) scan_clauses);
2696 }
2697
2698 scan_plan = make_seqscan(tlist,
2699 scan_clauses,
2700 scan_relid);
2701
2702 copy_generic_path_info(&scan_plan->plan, best_path);
2703
2704 return scan_plan;
2705 }
2706
2707 /*
2708 * create_samplescan_plan
2709 * Returns a samplescan plan for the base relation scanned by 'best_path'
2710 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
2711 */
2712 static SampleScan *
create_samplescan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)2713 create_samplescan_plan(PlannerInfo *root, Path *best_path,
2714 List *tlist, List *scan_clauses)
2715 {
2716 SampleScan *scan_plan;
2717 Index scan_relid = best_path->parent->relid;
2718 RangeTblEntry *rte;
2719 TableSampleClause *tsc;
2720
2721 /* it should be a base rel with a tablesample clause... */
2722 Assert(scan_relid > 0);
2723 rte = planner_rt_fetch(scan_relid, root);
2724 Assert(rte->rtekind == RTE_RELATION);
2725 tsc = rte->tablesample;
2726 Assert(tsc != NULL);
2727
2728 /* Sort clauses into best execution order */
2729 scan_clauses = order_qual_clauses(root, scan_clauses);
2730
2731 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
2732 scan_clauses = extract_actual_clauses(scan_clauses, false);
2733
2734 /* Replace any outer-relation variables with nestloop params */
2735 if (best_path->param_info)
2736 {
2737 scan_clauses = (List *)
2738 replace_nestloop_params(root, (Node *) scan_clauses);
2739 tsc = (TableSampleClause *)
2740 replace_nestloop_params(root, (Node *) tsc);
2741 }
2742
2743 scan_plan = make_samplescan(tlist,
2744 scan_clauses,
2745 scan_relid,
2746 tsc);
2747
2748 copy_generic_path_info(&scan_plan->scan.plan, best_path);
2749
2750 return scan_plan;
2751 }
2752
2753 /*
2754 * create_indexscan_plan
2755 * Returns an indexscan plan for the base relation scanned by 'best_path'
2756 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
2757 *
2758 * We use this for both plain IndexScans and IndexOnlyScans, because the
2759 * qual preprocessing work is the same for both. Note that the caller tells
2760 * us which to build --- we don't look at best_path->path.pathtype, because
2761 * create_bitmap_subplan needs to be able to override the prior decision.
2762 */
2763 static Scan *
create_indexscan_plan(PlannerInfo * root,IndexPath * best_path,List * tlist,List * scan_clauses,bool indexonly)2764 create_indexscan_plan(PlannerInfo *root,
2765 IndexPath *best_path,
2766 List *tlist,
2767 List *scan_clauses,
2768 bool indexonly)
2769 {
2770 Scan *scan_plan;
2771 List *indexclauses = best_path->indexclauses;
2772 List *indexorderbys = best_path->indexorderbys;
2773 Index baserelid = best_path->path.parent->relid;
2774 Oid indexoid = best_path->indexinfo->indexoid;
2775 List *qpqual;
2776 List *stripped_indexquals;
2777 List *fixed_indexquals;
2778 List *fixed_indexorderbys;
2779 List *indexorderbyops = NIL;
2780 ListCell *l;
2781
2782 /* it should be a base rel... */
2783 Assert(baserelid > 0);
2784 Assert(best_path->path.parent->rtekind == RTE_RELATION);
2785
2786 /*
2787 * Extract the index qual expressions (stripped of RestrictInfos) from the
2788 * IndexClauses list, and prepare a copy with index Vars substituted for
2789 * table Vars. (This step also does replace_nestloop_params on the
2790 * fixed_indexquals.)
2791 */
2792 fix_indexqual_references(root, best_path,
2793 &stripped_indexquals,
2794 &fixed_indexquals);
2795
2796 /*
2797 * Likewise fix up index attr references in the ORDER BY expressions.
2798 */
2799 fixed_indexorderbys = fix_indexorderby_references(root, best_path);
2800
2801 /*
2802 * The qpqual list must contain all restrictions not automatically handled
2803 * by the index, other than pseudoconstant clauses which will be handled
2804 * by a separate gating plan node. All the predicates in the indexquals
2805 * will be checked (either by the index itself, or by nodeIndexscan.c),
2806 * but if there are any "special" operators involved then they must be
2807 * included in qpqual. The upshot is that qpqual must contain
2808 * scan_clauses minus whatever appears in indexquals.
2809 *
2810 * is_redundant_with_indexclauses() detects cases where a scan clause is
2811 * present in the indexclauses list or is generated from the same
2812 * EquivalenceClass as some indexclause, and is therefore redundant with
2813 * it, though not equal. (The latter happens when indxpath.c prefers a
2814 * different derived equality than what generate_join_implied_equalities
2815 * picked for a parameterized scan's ppi_clauses.) Note that it will not
2816 * match to lossy index clauses, which is critical because we have to
2817 * include the original clause in qpqual in that case.
2818 *
2819 * In some situations (particularly with OR'd index conditions) we may
2820 * have scan_clauses that are not equal to, but are logically implied by,
2821 * the index quals; so we also try a predicate_implied_by() check to see
2822 * if we can discard quals that way. (predicate_implied_by assumes its
2823 * first input contains only immutable functions, so we have to check
2824 * that.)
2825 *
2826 * Note: if you change this bit of code you should also look at
2827 * extract_nonindex_conditions() in costsize.c.
2828 */
2829 qpqual = NIL;
2830 foreach(l, scan_clauses)
2831 {
2832 RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
2833
2834 if (rinfo->pseudoconstant)
2835 continue; /* we may drop pseudoconstants here */
2836 if (is_redundant_with_indexclauses(rinfo, indexclauses))
2837 continue; /* dup or derived from same EquivalenceClass */
2838 if (!contain_mutable_functions((Node *) rinfo->clause) &&
2839 predicate_implied_by(list_make1(rinfo->clause), stripped_indexquals,
2840 false))
2841 continue; /* provably implied by indexquals */
2842 qpqual = lappend(qpqual, rinfo);
2843 }
2844
2845 /* Sort clauses into best execution order */
2846 qpqual = order_qual_clauses(root, qpqual);
2847
2848 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
2849 qpqual = extract_actual_clauses(qpqual, false);
2850
2851 /*
2852 * We have to replace any outer-relation variables with nestloop params in
2853 * the indexqualorig, qpqual, and indexorderbyorig expressions. A bit
2854 * annoying to have to do this separately from the processing in
2855 * fix_indexqual_references --- rethink this when generalizing the inner
2856 * indexscan support. But note we can't really do this earlier because
2857 * it'd break the comparisons to predicates above ... (or would it? Those
2858 * wouldn't have outer refs)
2859 */
2860 if (best_path->path.param_info)
2861 {
2862 stripped_indexquals = (List *)
2863 replace_nestloop_params(root, (Node *) stripped_indexquals);
2864 qpqual = (List *)
2865 replace_nestloop_params(root, (Node *) qpqual);
2866 indexorderbys = (List *)
2867 replace_nestloop_params(root, (Node *) indexorderbys);
2868 }
2869
2870 /*
2871 * If there are ORDER BY expressions, look up the sort operators for their
2872 * result datatypes.
2873 */
2874 if (indexorderbys)
2875 {
2876 ListCell *pathkeyCell,
2877 *exprCell;
2878
2879 /*
2880 * PathKey contains OID of the btree opfamily we're sorting by, but
2881 * that's not quite enough because we need the expression's datatype
2882 * to look up the sort operator in the operator family.
2883 */
2884 Assert(list_length(best_path->path.pathkeys) == list_length(indexorderbys));
2885 forboth(pathkeyCell, best_path->path.pathkeys, exprCell, indexorderbys)
2886 {
2887 PathKey *pathkey = (PathKey *) lfirst(pathkeyCell);
2888 Node *expr = (Node *) lfirst(exprCell);
2889 Oid exprtype = exprType(expr);
2890 Oid sortop;
2891
2892 /* Get sort operator from opfamily */
2893 sortop = get_opfamily_member(pathkey->pk_opfamily,
2894 exprtype,
2895 exprtype,
2896 pathkey->pk_strategy);
2897 if (!OidIsValid(sortop))
2898 elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
2899 pathkey->pk_strategy, exprtype, exprtype, pathkey->pk_opfamily);
2900 indexorderbyops = lappend_oid(indexorderbyops, sortop);
2901 }
2902 }
2903
2904 /* Finally ready to build the plan node */
2905 if (indexonly)
2906 scan_plan = (Scan *) make_indexonlyscan(tlist,
2907 qpqual,
2908 baserelid,
2909 indexoid,
2910 fixed_indexquals,
2911 fixed_indexorderbys,
2912 best_path->indexinfo->indextlist,
2913 best_path->indexscandir);
2914 else
2915 scan_plan = (Scan *) make_indexscan(tlist,
2916 qpqual,
2917 baserelid,
2918 indexoid,
2919 fixed_indexquals,
2920 stripped_indexquals,
2921 fixed_indexorderbys,
2922 indexorderbys,
2923 indexorderbyops,
2924 best_path->indexscandir);
2925
2926 copy_generic_path_info(&scan_plan->plan, &best_path->path);
2927
2928 return scan_plan;
2929 }
2930
2931 /*
2932 * create_bitmap_scan_plan
2933 * Returns a bitmap scan plan for the base relation scanned by 'best_path'
2934 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
2935 */
2936 static BitmapHeapScan *
create_bitmap_scan_plan(PlannerInfo * root,BitmapHeapPath * best_path,List * tlist,List * scan_clauses)2937 create_bitmap_scan_plan(PlannerInfo *root,
2938 BitmapHeapPath *best_path,
2939 List *tlist,
2940 List *scan_clauses)
2941 {
2942 Index baserelid = best_path->path.parent->relid;
2943 Plan *bitmapqualplan;
2944 List *bitmapqualorig;
2945 List *indexquals;
2946 List *indexECs;
2947 List *qpqual;
2948 ListCell *l;
2949 BitmapHeapScan *scan_plan;
2950
2951 /* it should be a base rel... */
2952 Assert(baserelid > 0);
2953 Assert(best_path->path.parent->rtekind == RTE_RELATION);
2954
2955 /* Process the bitmapqual tree into a Plan tree and qual lists */
2956 bitmapqualplan = create_bitmap_subplan(root, best_path->bitmapqual,
2957 &bitmapqualorig, &indexquals,
2958 &indexECs);
2959
2960 if (best_path->path.parallel_aware)
2961 bitmap_subplan_mark_shared(bitmapqualplan);
2962
2963 /*
2964 * The qpqual list must contain all restrictions not automatically handled
2965 * by the index, other than pseudoconstant clauses which will be handled
2966 * by a separate gating plan node. All the predicates in the indexquals
2967 * will be checked (either by the index itself, or by
2968 * nodeBitmapHeapscan.c), but if there are any "special" operators
2969 * involved then they must be added to qpqual. The upshot is that qpqual
2970 * must contain scan_clauses minus whatever appears in indexquals.
2971 *
2972 * This loop is similar to the comparable code in create_indexscan_plan(),
2973 * but with some differences because it has to compare the scan clauses to
2974 * stripped (no RestrictInfos) indexquals. See comments there for more
2975 * info.
2976 *
2977 * In normal cases simple equal() checks will be enough to spot duplicate
2978 * clauses, so we try that first. We next see if the scan clause is
2979 * redundant with any top-level indexqual by virtue of being generated
2980 * from the same EC. After that, try predicate_implied_by().
2981 *
2982 * Unlike create_indexscan_plan(), the predicate_implied_by() test here is
2983 * useful for getting rid of qpquals that are implied by index predicates,
2984 * because the predicate conditions are included in the "indexquals"
2985 * returned by create_bitmap_subplan(). Bitmap scans have to do it that
2986 * way because predicate conditions need to be rechecked if the scan
2987 * becomes lossy, so they have to be included in bitmapqualorig.
2988 */
2989 qpqual = NIL;
2990 foreach(l, scan_clauses)
2991 {
2992 RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
2993 Node *clause = (Node *) rinfo->clause;
2994
2995 if (rinfo->pseudoconstant)
2996 continue; /* we may drop pseudoconstants here */
2997 if (list_member(indexquals, clause))
2998 continue; /* simple duplicate */
2999 if (rinfo->parent_ec && list_member_ptr(indexECs, rinfo->parent_ec))
3000 continue; /* derived from same EquivalenceClass */
3001 if (!contain_mutable_functions(clause) &&
3002 predicate_implied_by(list_make1(clause), indexquals, false))
3003 continue; /* provably implied by indexquals */
3004 qpqual = lappend(qpqual, rinfo);
3005 }
3006
3007 /* Sort clauses into best execution order */
3008 qpqual = order_qual_clauses(root, qpqual);
3009
3010 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3011 qpqual = extract_actual_clauses(qpqual, false);
3012
3013 /*
3014 * When dealing with special operators, we will at this point have
3015 * duplicate clauses in qpqual and bitmapqualorig. We may as well drop
3016 * 'em from bitmapqualorig, since there's no point in making the tests
3017 * twice.
3018 */
3019 bitmapqualorig = list_difference_ptr(bitmapqualorig, qpqual);
3020
3021 /*
3022 * We have to replace any outer-relation variables with nestloop params in
3023 * the qpqual and bitmapqualorig expressions. (This was already done for
3024 * expressions attached to plan nodes in the bitmapqualplan tree.)
3025 */
3026 if (best_path->path.param_info)
3027 {
3028 qpqual = (List *)
3029 replace_nestloop_params(root, (Node *) qpqual);
3030 bitmapqualorig = (List *)
3031 replace_nestloop_params(root, (Node *) bitmapqualorig);
3032 }
3033
3034 /* Finally ready to build the plan node */
3035 scan_plan = make_bitmap_heapscan(tlist,
3036 qpqual,
3037 bitmapqualplan,
3038 bitmapqualorig,
3039 baserelid);
3040
3041 copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
3042
3043 return scan_plan;
3044 }
3045
3046 /*
3047 * Given a bitmapqual tree, generate the Plan tree that implements it
3048 *
3049 * As byproducts, we also return in *qual and *indexqual the qual lists
3050 * (in implicit-AND form, without RestrictInfos) describing the original index
3051 * conditions and the generated indexqual conditions. (These are the same in
3052 * simple cases, but when special index operators are involved, the former
3053 * list includes the special conditions while the latter includes the actual
3054 * indexable conditions derived from them.) Both lists include partial-index
3055 * predicates, because we have to recheck predicates as well as index
3056 * conditions if the bitmap scan becomes lossy.
3057 *
3058 * In addition, we return a list of EquivalenceClass pointers for all the
3059 * top-level indexquals that were possibly-redundantly derived from ECs.
3060 * This allows removal of scan_clauses that are redundant with such quals.
3061 * (We do not attempt to detect such redundancies for quals that are within
3062 * OR subtrees. This could be done in a less hacky way if we returned the
3063 * indexquals in RestrictInfo form, but that would be slower and still pretty
3064 * messy, since we'd have to build new RestrictInfos in many cases.)
3065 */
3066 static Plan *
create_bitmap_subplan(PlannerInfo * root,Path * bitmapqual,List ** qual,List ** indexqual,List ** indexECs)3067 create_bitmap_subplan(PlannerInfo *root, Path *bitmapqual,
3068 List **qual, List **indexqual, List **indexECs)
3069 {
3070 Plan *plan;
3071
3072 if (IsA(bitmapqual, BitmapAndPath))
3073 {
3074 BitmapAndPath *apath = (BitmapAndPath *) bitmapqual;
3075 List *subplans = NIL;
3076 List *subquals = NIL;
3077 List *subindexquals = NIL;
3078 List *subindexECs = NIL;
3079 ListCell *l;
3080
3081 /*
3082 * There may well be redundant quals among the subplans, since a
3083 * top-level WHERE qual might have gotten used to form several
3084 * different index quals. We don't try exceedingly hard to eliminate
3085 * redundancies, but we do eliminate obvious duplicates by using
3086 * list_concat_unique.
3087 */
3088 foreach(l, apath->bitmapquals)
3089 {
3090 Plan *subplan;
3091 List *subqual;
3092 List *subindexqual;
3093 List *subindexEC;
3094
3095 subplan = create_bitmap_subplan(root, (Path *) lfirst(l),
3096 &subqual, &subindexqual,
3097 &subindexEC);
3098 subplans = lappend(subplans, subplan);
3099 subquals = list_concat_unique(subquals, subqual);
3100 subindexquals = list_concat_unique(subindexquals, subindexqual);
3101 /* Duplicates in indexECs aren't worth getting rid of */
3102 subindexECs = list_concat(subindexECs, subindexEC);
3103 }
3104 plan = (Plan *) make_bitmap_and(subplans);
3105 plan->startup_cost = apath->path.startup_cost;
3106 plan->total_cost = apath->path.total_cost;
3107 plan->plan_rows =
3108 clamp_row_est(apath->bitmapselectivity * apath->path.parent->tuples);
3109 plan->plan_width = 0; /* meaningless */
3110 plan->parallel_aware = false;
3111 plan->parallel_safe = apath->path.parallel_safe;
3112 *qual = subquals;
3113 *indexqual = subindexquals;
3114 *indexECs = subindexECs;
3115 }
3116 else if (IsA(bitmapqual, BitmapOrPath))
3117 {
3118 BitmapOrPath *opath = (BitmapOrPath *) bitmapqual;
3119 List *subplans = NIL;
3120 List *subquals = NIL;
3121 List *subindexquals = NIL;
3122 bool const_true_subqual = false;
3123 bool const_true_subindexqual = false;
3124 ListCell *l;
3125
3126 /*
3127 * Here, we only detect qual-free subplans. A qual-free subplan would
3128 * cause us to generate "... OR true ..." which we may as well reduce
3129 * to just "true". We do not try to eliminate redundant subclauses
3130 * because (a) it's not as likely as in the AND case, and (b) we might
3131 * well be working with hundreds or even thousands of OR conditions,
3132 * perhaps from a long IN list. The performance of list_append_unique
3133 * would be unacceptable.
3134 */
3135 foreach(l, opath->bitmapquals)
3136 {
3137 Plan *subplan;
3138 List *subqual;
3139 List *subindexqual;
3140 List *subindexEC;
3141
3142 subplan = create_bitmap_subplan(root, (Path *) lfirst(l),
3143 &subqual, &subindexqual,
3144 &subindexEC);
3145 subplans = lappend(subplans, subplan);
3146 if (subqual == NIL)
3147 const_true_subqual = true;
3148 else if (!const_true_subqual)
3149 subquals = lappend(subquals,
3150 make_ands_explicit(subqual));
3151 if (subindexqual == NIL)
3152 const_true_subindexqual = true;
3153 else if (!const_true_subindexqual)
3154 subindexquals = lappend(subindexquals,
3155 make_ands_explicit(subindexqual));
3156 }
3157
3158 /*
3159 * In the presence of ScalarArrayOpExpr quals, we might have built
3160 * BitmapOrPaths with just one subpath; don't add an OR step.
3161 */
3162 if (list_length(subplans) == 1)
3163 {
3164 plan = (Plan *) linitial(subplans);
3165 }
3166 else
3167 {
3168 plan = (Plan *) make_bitmap_or(subplans);
3169 plan->startup_cost = opath->path.startup_cost;
3170 plan->total_cost = opath->path.total_cost;
3171 plan->plan_rows =
3172 clamp_row_est(opath->bitmapselectivity * opath->path.parent->tuples);
3173 plan->plan_width = 0; /* meaningless */
3174 plan->parallel_aware = false;
3175 plan->parallel_safe = opath->path.parallel_safe;
3176 }
3177
3178 /*
3179 * If there were constant-TRUE subquals, the OR reduces to constant
3180 * TRUE. Also, avoid generating one-element ORs, which could happen
3181 * due to redundancy elimination or ScalarArrayOpExpr quals.
3182 */
3183 if (const_true_subqual)
3184 *qual = NIL;
3185 else if (list_length(subquals) <= 1)
3186 *qual = subquals;
3187 else
3188 *qual = list_make1(make_orclause(subquals));
3189 if (const_true_subindexqual)
3190 *indexqual = NIL;
3191 else if (list_length(subindexquals) <= 1)
3192 *indexqual = subindexquals;
3193 else
3194 *indexqual = list_make1(make_orclause(subindexquals));
3195 *indexECs = NIL;
3196 }
3197 else if (IsA(bitmapqual, IndexPath))
3198 {
3199 IndexPath *ipath = (IndexPath *) bitmapqual;
3200 IndexScan *iscan;
3201 List *subquals;
3202 List *subindexquals;
3203 List *subindexECs;
3204 ListCell *l;
3205
3206 /* Use the regular indexscan plan build machinery... */
3207 iscan = castNode(IndexScan,
3208 create_indexscan_plan(root, ipath,
3209 NIL, NIL, false));
3210 /* then convert to a bitmap indexscan */
3211 plan = (Plan *) make_bitmap_indexscan(iscan->scan.scanrelid,
3212 iscan->indexid,
3213 iscan->indexqual,
3214 iscan->indexqualorig);
3215 /* and set its cost/width fields appropriately */
3216 plan->startup_cost = 0.0;
3217 plan->total_cost = ipath->indextotalcost;
3218 plan->plan_rows =
3219 clamp_row_est(ipath->indexselectivity * ipath->path.parent->tuples);
3220 plan->plan_width = 0; /* meaningless */
3221 plan->parallel_aware = false;
3222 plan->parallel_safe = ipath->path.parallel_safe;
3223 /* Extract original index clauses, actual index quals, relevant ECs */
3224 subquals = NIL;
3225 subindexquals = NIL;
3226 subindexECs = NIL;
3227 foreach(l, ipath->indexclauses)
3228 {
3229 IndexClause *iclause = (IndexClause *) lfirst(l);
3230 RestrictInfo *rinfo = iclause->rinfo;
3231
3232 Assert(!rinfo->pseudoconstant);
3233 subquals = lappend(subquals, rinfo->clause);
3234 subindexquals = list_concat(subindexquals,
3235 get_actual_clauses(iclause->indexquals));
3236 if (rinfo->parent_ec)
3237 subindexECs = lappend(subindexECs, rinfo->parent_ec);
3238 }
3239 /* We can add any index predicate conditions, too */
3240 foreach(l, ipath->indexinfo->indpred)
3241 {
3242 Expr *pred = (Expr *) lfirst(l);
3243
3244 /*
3245 * We know that the index predicate must have been implied by the
3246 * query condition as a whole, but it may or may not be implied by
3247 * the conditions that got pushed into the bitmapqual. Avoid
3248 * generating redundant conditions.
3249 */
3250 if (!predicate_implied_by(list_make1(pred), subquals, false))
3251 {
3252 subquals = lappend(subquals, pred);
3253 subindexquals = lappend(subindexquals, pred);
3254 }
3255 }
3256 *qual = subquals;
3257 *indexqual = subindexquals;
3258 *indexECs = subindexECs;
3259 }
3260 else
3261 {
3262 elog(ERROR, "unrecognized node type: %d", nodeTag(bitmapqual));
3263 plan = NULL; /* keep compiler quiet */
3264 }
3265
3266 return plan;
3267 }
3268
3269 /*
3270 * create_tidscan_plan
3271 * Returns a tidscan plan for the base relation scanned by 'best_path'
3272 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3273 */
3274 static TidScan *
create_tidscan_plan(PlannerInfo * root,TidPath * best_path,List * tlist,List * scan_clauses)3275 create_tidscan_plan(PlannerInfo *root, TidPath *best_path,
3276 List *tlist, List *scan_clauses)
3277 {
3278 TidScan *scan_plan;
3279 Index scan_relid = best_path->path.parent->relid;
3280 List *tidquals = best_path->tidquals;
3281
3282 /* it should be a base rel... */
3283 Assert(scan_relid > 0);
3284 Assert(best_path->path.parent->rtekind == RTE_RELATION);
3285
3286 /*
3287 * The qpqual list must contain all restrictions not enforced by the
3288 * tidquals list. Since tidquals has OR semantics, we have to be careful
3289 * about matching it up to scan_clauses. It's convenient to handle the
3290 * single-tidqual case separately from the multiple-tidqual case. In the
3291 * single-tidqual case, we look through the scan_clauses while they are
3292 * still in RestrictInfo form, and drop any that are redundant with the
3293 * tidqual.
3294 *
3295 * In normal cases simple pointer equality checks will be enough to spot
3296 * duplicate RestrictInfos, so we try that first.
3297 *
3298 * Another common case is that a scan_clauses entry is generated from the
3299 * same EquivalenceClass as some tidqual, and is therefore redundant with
3300 * it, though not equal.
3301 *
3302 * Unlike indexpaths, we don't bother with predicate_implied_by(); the
3303 * number of cases where it could win are pretty small.
3304 */
3305 if (list_length(tidquals) == 1)
3306 {
3307 List *qpqual = NIL;
3308 ListCell *l;
3309
3310 foreach(l, scan_clauses)
3311 {
3312 RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
3313
3314 if (rinfo->pseudoconstant)
3315 continue; /* we may drop pseudoconstants here */
3316 if (list_member_ptr(tidquals, rinfo))
3317 continue; /* simple duplicate */
3318 if (is_redundant_derived_clause(rinfo, tidquals))
3319 continue; /* derived from same EquivalenceClass */
3320 qpqual = lappend(qpqual, rinfo);
3321 }
3322 scan_clauses = qpqual;
3323 }
3324
3325 /* Sort clauses into best execution order */
3326 scan_clauses = order_qual_clauses(root, scan_clauses);
3327
3328 /* Reduce RestrictInfo lists to bare expressions; ignore pseudoconstants */
3329 tidquals = extract_actual_clauses(tidquals, false);
3330 scan_clauses = extract_actual_clauses(scan_clauses, false);
3331
3332 /*
3333 * If we have multiple tidquals, it's more convenient to remove duplicate
3334 * scan_clauses after stripping the RestrictInfos. In this situation,
3335 * because the tidquals represent OR sub-clauses, they could not have come
3336 * from EquivalenceClasses so we don't have to worry about matching up
3337 * non-identical clauses. On the other hand, because tidpath.c will have
3338 * extracted those sub-clauses from some OR clause and built its own list,
3339 * we will certainly not have pointer equality to any scan clause. So
3340 * convert the tidquals list to an explicit OR clause and see if we can
3341 * match it via equal() to any scan clause.
3342 */
3343 if (list_length(tidquals) > 1)
3344 scan_clauses = list_difference(scan_clauses,
3345 list_make1(make_orclause(tidquals)));
3346
3347 /* Replace any outer-relation variables with nestloop params */
3348 if (best_path->path.param_info)
3349 {
3350 tidquals = (List *)
3351 replace_nestloop_params(root, (Node *) tidquals);
3352 scan_clauses = (List *)
3353 replace_nestloop_params(root, (Node *) scan_clauses);
3354 }
3355
3356 scan_plan = make_tidscan(tlist,
3357 scan_clauses,
3358 scan_relid,
3359 tidquals);
3360
3361 copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
3362
3363 return scan_plan;
3364 }
3365
3366 /*
3367 * create_subqueryscan_plan
3368 * Returns a subqueryscan plan for the base relation scanned by 'best_path'
3369 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3370 */
3371 static SubqueryScan *
create_subqueryscan_plan(PlannerInfo * root,SubqueryScanPath * best_path,List * tlist,List * scan_clauses)3372 create_subqueryscan_plan(PlannerInfo *root, SubqueryScanPath *best_path,
3373 List *tlist, List *scan_clauses)
3374 {
3375 SubqueryScan *scan_plan;
3376 RelOptInfo *rel = best_path->path.parent;
3377 Index scan_relid = rel->relid;
3378 Plan *subplan;
3379
3380 /* it should be a subquery base rel... */
3381 Assert(scan_relid > 0);
3382 Assert(rel->rtekind == RTE_SUBQUERY);
3383
3384 /*
3385 * Recursively create Plan from Path for subquery. Since we are entering
3386 * a different planner context (subroot), recurse to create_plan not
3387 * create_plan_recurse.
3388 */
3389 subplan = create_plan(rel->subroot, best_path->subpath);
3390
3391 /* Sort clauses into best execution order */
3392 scan_clauses = order_qual_clauses(root, scan_clauses);
3393
3394 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3395 scan_clauses = extract_actual_clauses(scan_clauses, false);
3396
3397 /* Replace any outer-relation variables with nestloop params */
3398 if (best_path->path.param_info)
3399 {
3400 scan_clauses = (List *)
3401 replace_nestloop_params(root, (Node *) scan_clauses);
3402 process_subquery_nestloop_params(root,
3403 rel->subplan_params);
3404 }
3405
3406 scan_plan = make_subqueryscan(tlist,
3407 scan_clauses,
3408 scan_relid,
3409 subplan);
3410
3411 copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
3412
3413 return scan_plan;
3414 }
3415
3416 /*
3417 * create_functionscan_plan
3418 * Returns a functionscan plan for the base relation scanned by 'best_path'
3419 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3420 */
3421 static FunctionScan *
create_functionscan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3422 create_functionscan_plan(PlannerInfo *root, Path *best_path,
3423 List *tlist, List *scan_clauses)
3424 {
3425 FunctionScan *scan_plan;
3426 Index scan_relid = best_path->parent->relid;
3427 RangeTblEntry *rte;
3428 List *functions;
3429
3430 /* it should be a function base rel... */
3431 Assert(scan_relid > 0);
3432 rte = planner_rt_fetch(scan_relid, root);
3433 Assert(rte->rtekind == RTE_FUNCTION);
3434 functions = rte->functions;
3435
3436 /* Sort clauses into best execution order */
3437 scan_clauses = order_qual_clauses(root, scan_clauses);
3438
3439 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3440 scan_clauses = extract_actual_clauses(scan_clauses, false);
3441
3442 /* Replace any outer-relation variables with nestloop params */
3443 if (best_path->param_info)
3444 {
3445 scan_clauses = (List *)
3446 replace_nestloop_params(root, (Node *) scan_clauses);
3447 /* The function expressions could contain nestloop params, too */
3448 functions = (List *) replace_nestloop_params(root, (Node *) functions);
3449 }
3450
3451 scan_plan = make_functionscan(tlist, scan_clauses, scan_relid,
3452 functions, rte->funcordinality);
3453
3454 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3455
3456 return scan_plan;
3457 }
3458
3459 /*
3460 * create_tablefuncscan_plan
3461 * Returns a tablefuncscan plan for the base relation scanned by 'best_path'
3462 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3463 */
3464 static TableFuncScan *
create_tablefuncscan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3465 create_tablefuncscan_plan(PlannerInfo *root, Path *best_path,
3466 List *tlist, List *scan_clauses)
3467 {
3468 TableFuncScan *scan_plan;
3469 Index scan_relid = best_path->parent->relid;
3470 RangeTblEntry *rte;
3471 TableFunc *tablefunc;
3472
3473 /* it should be a function base rel... */
3474 Assert(scan_relid > 0);
3475 rte = planner_rt_fetch(scan_relid, root);
3476 Assert(rte->rtekind == RTE_TABLEFUNC);
3477 tablefunc = rte->tablefunc;
3478
3479 /* Sort clauses into best execution order */
3480 scan_clauses = order_qual_clauses(root, scan_clauses);
3481
3482 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3483 scan_clauses = extract_actual_clauses(scan_clauses, false);
3484
3485 /* Replace any outer-relation variables with nestloop params */
3486 if (best_path->param_info)
3487 {
3488 scan_clauses = (List *)
3489 replace_nestloop_params(root, (Node *) scan_clauses);
3490 /* The function expressions could contain nestloop params, too */
3491 tablefunc = (TableFunc *) replace_nestloop_params(root, (Node *) tablefunc);
3492 }
3493
3494 scan_plan = make_tablefuncscan(tlist, scan_clauses, scan_relid,
3495 tablefunc);
3496
3497 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3498
3499 return scan_plan;
3500 }
3501
3502 /*
3503 * create_valuesscan_plan
3504 * Returns a valuesscan plan for the base relation scanned by 'best_path'
3505 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3506 */
3507 static ValuesScan *
create_valuesscan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3508 create_valuesscan_plan(PlannerInfo *root, Path *best_path,
3509 List *tlist, List *scan_clauses)
3510 {
3511 ValuesScan *scan_plan;
3512 Index scan_relid = best_path->parent->relid;
3513 RangeTblEntry *rte;
3514 List *values_lists;
3515
3516 /* it should be a values base rel... */
3517 Assert(scan_relid > 0);
3518 rte = planner_rt_fetch(scan_relid, root);
3519 Assert(rte->rtekind == RTE_VALUES);
3520 values_lists = rte->values_lists;
3521
3522 /* Sort clauses into best execution order */
3523 scan_clauses = order_qual_clauses(root, scan_clauses);
3524
3525 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3526 scan_clauses = extract_actual_clauses(scan_clauses, false);
3527
3528 /* Replace any outer-relation variables with nestloop params */
3529 if (best_path->param_info)
3530 {
3531 scan_clauses = (List *)
3532 replace_nestloop_params(root, (Node *) scan_clauses);
3533 /* The values lists could contain nestloop params, too */
3534 values_lists = (List *)
3535 replace_nestloop_params(root, (Node *) values_lists);
3536 }
3537
3538 scan_plan = make_valuesscan(tlist, scan_clauses, scan_relid,
3539 values_lists);
3540
3541 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3542
3543 return scan_plan;
3544 }
3545
3546 /*
3547 * create_ctescan_plan
3548 * Returns a ctescan plan for the base relation scanned by 'best_path'
3549 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3550 */
3551 static CteScan *
create_ctescan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3552 create_ctescan_plan(PlannerInfo *root, Path *best_path,
3553 List *tlist, List *scan_clauses)
3554 {
3555 CteScan *scan_plan;
3556 Index scan_relid = best_path->parent->relid;
3557 RangeTblEntry *rte;
3558 SubPlan *ctesplan = NULL;
3559 int plan_id;
3560 int cte_param_id;
3561 PlannerInfo *cteroot;
3562 Index levelsup;
3563 int ndx;
3564 ListCell *lc;
3565
3566 Assert(scan_relid > 0);
3567 rte = planner_rt_fetch(scan_relid, root);
3568 Assert(rte->rtekind == RTE_CTE);
3569 Assert(!rte->self_reference);
3570
3571 /*
3572 * Find the referenced CTE, and locate the SubPlan previously made for it.
3573 */
3574 levelsup = rte->ctelevelsup;
3575 cteroot = root;
3576 while (levelsup-- > 0)
3577 {
3578 cteroot = cteroot->parent_root;
3579 if (!cteroot) /* shouldn't happen */
3580 elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
3581 }
3582
3583 /*
3584 * Note: cte_plan_ids can be shorter than cteList, if we are still working
3585 * on planning the CTEs (ie, this is a side-reference from another CTE).
3586 * So we mustn't use forboth here.
3587 */
3588 ndx = 0;
3589 foreach(lc, cteroot->parse->cteList)
3590 {
3591 CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
3592
3593 if (strcmp(cte->ctename, rte->ctename) == 0)
3594 break;
3595 ndx++;
3596 }
3597 if (lc == NULL) /* shouldn't happen */
3598 elog(ERROR, "could not find CTE \"%s\"", rte->ctename);
3599 if (ndx >= list_length(cteroot->cte_plan_ids))
3600 elog(ERROR, "could not find plan for CTE \"%s\"", rte->ctename);
3601 plan_id = list_nth_int(cteroot->cte_plan_ids, ndx);
3602 Assert(plan_id > 0);
3603 foreach(lc, cteroot->init_plans)
3604 {
3605 ctesplan = (SubPlan *) lfirst(lc);
3606 if (ctesplan->plan_id == plan_id)
3607 break;
3608 }
3609 if (lc == NULL) /* shouldn't happen */
3610 elog(ERROR, "could not find plan for CTE \"%s\"", rte->ctename);
3611
3612 /*
3613 * We need the CTE param ID, which is the sole member of the SubPlan's
3614 * setParam list.
3615 */
3616 cte_param_id = linitial_int(ctesplan->setParam);
3617
3618 /* Sort clauses into best execution order */
3619 scan_clauses = order_qual_clauses(root, scan_clauses);
3620
3621 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3622 scan_clauses = extract_actual_clauses(scan_clauses, false);
3623
3624 /* Replace any outer-relation variables with nestloop params */
3625 if (best_path->param_info)
3626 {
3627 scan_clauses = (List *)
3628 replace_nestloop_params(root, (Node *) scan_clauses);
3629 }
3630
3631 scan_plan = make_ctescan(tlist, scan_clauses, scan_relid,
3632 plan_id, cte_param_id);
3633
3634 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3635
3636 return scan_plan;
3637 }
3638
3639 /*
3640 * create_namedtuplestorescan_plan
3641 * Returns a tuplestorescan plan for the base relation scanned by
3642 * 'best_path' with restriction clauses 'scan_clauses' and targetlist
3643 * 'tlist'.
3644 */
3645 static NamedTuplestoreScan *
create_namedtuplestorescan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3646 create_namedtuplestorescan_plan(PlannerInfo *root, Path *best_path,
3647 List *tlist, List *scan_clauses)
3648 {
3649 NamedTuplestoreScan *scan_plan;
3650 Index scan_relid = best_path->parent->relid;
3651 RangeTblEntry *rte;
3652
3653 Assert(scan_relid > 0);
3654 rte = planner_rt_fetch(scan_relid, root);
3655 Assert(rte->rtekind == RTE_NAMEDTUPLESTORE);
3656
3657 /* Sort clauses into best execution order */
3658 scan_clauses = order_qual_clauses(root, scan_clauses);
3659
3660 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3661 scan_clauses = extract_actual_clauses(scan_clauses, false);
3662
3663 /* Replace any outer-relation variables with nestloop params */
3664 if (best_path->param_info)
3665 {
3666 scan_clauses = (List *)
3667 replace_nestloop_params(root, (Node *) scan_clauses);
3668 }
3669
3670 scan_plan = make_namedtuplestorescan(tlist, scan_clauses, scan_relid,
3671 rte->enrname);
3672
3673 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3674
3675 return scan_plan;
3676 }
3677
3678 /*
3679 * create_resultscan_plan
3680 * Returns a Result plan for the RTE_RESULT base relation scanned by
3681 * 'best_path' with restriction clauses 'scan_clauses' and targetlist
3682 * 'tlist'.
3683 */
3684 static Result *
create_resultscan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3685 create_resultscan_plan(PlannerInfo *root, Path *best_path,
3686 List *tlist, List *scan_clauses)
3687 {
3688 Result *scan_plan;
3689 Index scan_relid = best_path->parent->relid;
3690 RangeTblEntry *rte PG_USED_FOR_ASSERTS_ONLY;
3691
3692 Assert(scan_relid > 0);
3693 rte = planner_rt_fetch(scan_relid, root);
3694 Assert(rte->rtekind == RTE_RESULT);
3695
3696 /* Sort clauses into best execution order */
3697 scan_clauses = order_qual_clauses(root, scan_clauses);
3698
3699 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3700 scan_clauses = extract_actual_clauses(scan_clauses, false);
3701
3702 /* Replace any outer-relation variables with nestloop params */
3703 if (best_path->param_info)
3704 {
3705 scan_clauses = (List *)
3706 replace_nestloop_params(root, (Node *) scan_clauses);
3707 }
3708
3709 scan_plan = make_result(tlist, (Node *) scan_clauses, NULL);
3710
3711 copy_generic_path_info(&scan_plan->plan, best_path);
3712
3713 return scan_plan;
3714 }
3715
3716 /*
3717 * create_worktablescan_plan
3718 * Returns a worktablescan plan for the base relation scanned by 'best_path'
3719 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3720 */
3721 static WorkTableScan *
create_worktablescan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3722 create_worktablescan_plan(PlannerInfo *root, Path *best_path,
3723 List *tlist, List *scan_clauses)
3724 {
3725 WorkTableScan *scan_plan;
3726 Index scan_relid = best_path->parent->relid;
3727 RangeTblEntry *rte;
3728 Index levelsup;
3729 PlannerInfo *cteroot;
3730
3731 Assert(scan_relid > 0);
3732 rte = planner_rt_fetch(scan_relid, root);
3733 Assert(rte->rtekind == RTE_CTE);
3734 Assert(rte->self_reference);
3735
3736 /*
3737 * We need to find the worktable param ID, which is in the plan level
3738 * that's processing the recursive UNION, which is one level *below* where
3739 * the CTE comes from.
3740 */
3741 levelsup = rte->ctelevelsup;
3742 if (levelsup == 0) /* shouldn't happen */
3743 elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
3744 levelsup--;
3745 cteroot = root;
3746 while (levelsup-- > 0)
3747 {
3748 cteroot = cteroot->parent_root;
3749 if (!cteroot) /* shouldn't happen */
3750 elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
3751 }
3752 if (cteroot->wt_param_id < 0) /* shouldn't happen */
3753 elog(ERROR, "could not find param ID for CTE \"%s\"", rte->ctename);
3754
3755 /* Sort clauses into best execution order */
3756 scan_clauses = order_qual_clauses(root, scan_clauses);
3757
3758 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3759 scan_clauses = extract_actual_clauses(scan_clauses, false);
3760
3761 /* Replace any outer-relation variables with nestloop params */
3762 if (best_path->param_info)
3763 {
3764 scan_clauses = (List *)
3765 replace_nestloop_params(root, (Node *) scan_clauses);
3766 }
3767
3768 scan_plan = make_worktablescan(tlist, scan_clauses, scan_relid,
3769 cteroot->wt_param_id);
3770
3771 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3772
3773 return scan_plan;
3774 }
3775
3776 /*
3777 * create_foreignscan_plan
3778 * Returns a foreignscan plan for the relation scanned by 'best_path'
3779 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3780 */
3781 static ForeignScan *
create_foreignscan_plan(PlannerInfo * root,ForeignPath * best_path,List * tlist,List * scan_clauses)3782 create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path,
3783 List *tlist, List *scan_clauses)
3784 {
3785 ForeignScan *scan_plan;
3786 RelOptInfo *rel = best_path->path.parent;
3787 Index scan_relid = rel->relid;
3788 Oid rel_oid = InvalidOid;
3789 Plan *outer_plan = NULL;
3790
3791 Assert(rel->fdwroutine != NULL);
3792
3793 /* transform the child path if any */
3794 if (best_path->fdw_outerpath)
3795 outer_plan = create_plan_recurse(root, best_path->fdw_outerpath,
3796 CP_EXACT_TLIST);
3797
3798 /*
3799 * If we're scanning a base relation, fetch its OID. (Irrelevant if
3800 * scanning a join relation.)
3801 */
3802 if (scan_relid > 0)
3803 {
3804 RangeTblEntry *rte;
3805
3806 Assert(rel->rtekind == RTE_RELATION);
3807 rte = planner_rt_fetch(scan_relid, root);
3808 Assert(rte->rtekind == RTE_RELATION);
3809 rel_oid = rte->relid;
3810 }
3811
3812 /*
3813 * Sort clauses into best execution order. We do this first since the FDW
3814 * might have more info than we do and wish to adjust the ordering.
3815 */
3816 scan_clauses = order_qual_clauses(root, scan_clauses);
3817
3818 /*
3819 * Let the FDW perform its processing on the restriction clauses and
3820 * generate the plan node. Note that the FDW might remove restriction
3821 * clauses that it intends to execute remotely, or even add more (if it
3822 * has selected some join clauses for remote use but also wants them
3823 * rechecked locally).
3824 */
3825 scan_plan = rel->fdwroutine->GetForeignPlan(root, rel, rel_oid,
3826 best_path,
3827 tlist, scan_clauses,
3828 outer_plan);
3829
3830 /* Copy cost data from Path to Plan; no need to make FDW do this */
3831 copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
3832
3833 /* Copy foreign server OID; likewise, no need to make FDW do this */
3834 scan_plan->fs_server = rel->serverid;
3835
3836 /*
3837 * Likewise, copy the relids that are represented by this foreign scan. An
3838 * upper rel doesn't have relids set, but it covers all the base relations
3839 * participating in the underlying scan, so use root's all_baserels.
3840 */
3841 if (rel->reloptkind == RELOPT_UPPER_REL)
3842 scan_plan->fs_relids = root->all_baserels;
3843 else
3844 scan_plan->fs_relids = best_path->path.parent->relids;
3845
3846 /*
3847 * If this is a foreign join, and to make it valid to push down we had to
3848 * assume that the current user is the same as some user explicitly named
3849 * in the query, mark the finished plan as depending on the current user.
3850 */
3851 if (rel->useridiscurrent)
3852 root->glob->dependsOnRole = true;
3853
3854 /*
3855 * Replace any outer-relation variables with nestloop params in the qual,
3856 * fdw_exprs and fdw_recheck_quals expressions. We do this last so that
3857 * the FDW doesn't have to be involved. (Note that parts of fdw_exprs or
3858 * fdw_recheck_quals could have come from join clauses, so doing this
3859 * beforehand on the scan_clauses wouldn't work.) We assume
3860 * fdw_scan_tlist contains no such variables.
3861 */
3862 if (best_path->path.param_info)
3863 {
3864 scan_plan->scan.plan.qual = (List *)
3865 replace_nestloop_params(root, (Node *) scan_plan->scan.plan.qual);
3866 scan_plan->fdw_exprs = (List *)
3867 replace_nestloop_params(root, (Node *) scan_plan->fdw_exprs);
3868 scan_plan->fdw_recheck_quals = (List *)
3869 replace_nestloop_params(root,
3870 (Node *) scan_plan->fdw_recheck_quals);
3871 }
3872
3873 /*
3874 * If rel is a base relation, detect whether any system columns are
3875 * requested from the rel. (If rel is a join relation, rel->relid will be
3876 * 0, but there can be no Var with relid 0 in the rel's targetlist or the
3877 * restriction clauses, so we skip this in that case. Note that any such
3878 * columns in base relations that were joined are assumed to be contained
3879 * in fdw_scan_tlist.) This is a bit of a kluge and might go away
3880 * someday, so we intentionally leave it out of the API presented to FDWs.
3881 */
3882 scan_plan->fsSystemCol = false;
3883 if (scan_relid > 0)
3884 {
3885 Bitmapset *attrs_used = NULL;
3886 ListCell *lc;
3887 int i;
3888
3889 /*
3890 * First, examine all the attributes needed for joins or final output.
3891 * Note: we must look at rel's targetlist, not the attr_needed data,
3892 * because attr_needed isn't computed for inheritance child rels.
3893 */
3894 pull_varattnos((Node *) rel->reltarget->exprs, scan_relid, &attrs_used);
3895
3896 /* Add all the attributes used by restriction clauses. */
3897 foreach(lc, rel->baserestrictinfo)
3898 {
3899 RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
3900
3901 pull_varattnos((Node *) rinfo->clause, scan_relid, &attrs_used);
3902 }
3903
3904 /* Now, are any system columns requested from rel? */
3905 for (i = FirstLowInvalidHeapAttributeNumber + 1; i < 0; i++)
3906 {
3907 if (bms_is_member(i - FirstLowInvalidHeapAttributeNumber, attrs_used))
3908 {
3909 scan_plan->fsSystemCol = true;
3910 break;
3911 }
3912 }
3913
3914 bms_free(attrs_used);
3915 }
3916
3917 return scan_plan;
3918 }
3919
3920 /*
3921 * create_customscan_plan
3922 *
3923 * Transform a CustomPath into a Plan.
3924 */
3925 static CustomScan *
create_customscan_plan(PlannerInfo * root,CustomPath * best_path,List * tlist,List * scan_clauses)3926 create_customscan_plan(PlannerInfo *root, CustomPath *best_path,
3927 List *tlist, List *scan_clauses)
3928 {
3929 CustomScan *cplan;
3930 RelOptInfo *rel = best_path->path.parent;
3931 List *custom_plans = NIL;
3932 ListCell *lc;
3933
3934 /* Recursively transform child paths. */
3935 foreach(lc, best_path->custom_paths)
3936 {
3937 Plan *plan = create_plan_recurse(root, (Path *) lfirst(lc),
3938 CP_EXACT_TLIST);
3939
3940 custom_plans = lappend(custom_plans, plan);
3941 }
3942
3943 /*
3944 * Sort clauses into the best execution order, although custom-scan
3945 * provider can reorder them again.
3946 */
3947 scan_clauses = order_qual_clauses(root, scan_clauses);
3948
3949 /*
3950 * Invoke custom plan provider to create the Plan node represented by the
3951 * CustomPath.
3952 */
3953 cplan = castNode(CustomScan,
3954 best_path->methods->PlanCustomPath(root,
3955 rel,
3956 best_path,
3957 tlist,
3958 scan_clauses,
3959 custom_plans));
3960
3961 /*
3962 * Copy cost data from Path to Plan; no need to make custom-plan providers
3963 * do this
3964 */
3965 copy_generic_path_info(&cplan->scan.plan, &best_path->path);
3966
3967 /* Likewise, copy the relids that are represented by this custom scan */
3968 cplan->custom_relids = best_path->path.parent->relids;
3969
3970 /*
3971 * Replace any outer-relation variables with nestloop params in the qual
3972 * and custom_exprs expressions. We do this last so that the custom-plan
3973 * provider doesn't have to be involved. (Note that parts of custom_exprs
3974 * could have come from join clauses, so doing this beforehand on the
3975 * scan_clauses wouldn't work.) We assume custom_scan_tlist contains no
3976 * such variables.
3977 */
3978 if (best_path->path.param_info)
3979 {
3980 cplan->scan.plan.qual = (List *)
3981 replace_nestloop_params(root, (Node *) cplan->scan.plan.qual);
3982 cplan->custom_exprs = (List *)
3983 replace_nestloop_params(root, (Node *) cplan->custom_exprs);
3984 }
3985
3986 return cplan;
3987 }
3988
3989
3990 /*****************************************************************************
3991 *
3992 * JOIN METHODS
3993 *
3994 *****************************************************************************/
3995
3996 static NestLoop *
create_nestloop_plan(PlannerInfo * root,NestPath * best_path)3997 create_nestloop_plan(PlannerInfo *root,
3998 NestPath *best_path)
3999 {
4000 NestLoop *join_plan;
4001 Plan *outer_plan;
4002 Plan *inner_plan;
4003 List *tlist = build_path_tlist(root, &best_path->path);
4004 List *joinrestrictclauses = best_path->joinrestrictinfo;
4005 List *joinclauses;
4006 List *otherclauses;
4007 Relids outerrelids;
4008 List *nestParams;
4009 Relids saveOuterRels = root->curOuterRels;
4010
4011 /* NestLoop can project, so no need to be picky about child tlists */
4012 outer_plan = create_plan_recurse(root, best_path->outerjoinpath, 0);
4013
4014 /* For a nestloop, include outer relids in curOuterRels for inner side */
4015 root->curOuterRels = bms_union(root->curOuterRels,
4016 best_path->outerjoinpath->parent->relids);
4017
4018 inner_plan = create_plan_recurse(root, best_path->innerjoinpath, 0);
4019
4020 /* Restore curOuterRels */
4021 bms_free(root->curOuterRels);
4022 root->curOuterRels = saveOuterRels;
4023
4024 /* Sort join qual clauses into best execution order */
4025 joinrestrictclauses = order_qual_clauses(root, joinrestrictclauses);
4026
4027 /* Get the join qual clauses (in plain expression form) */
4028 /* Any pseudoconstant clauses are ignored here */
4029 if (IS_OUTER_JOIN(best_path->jointype))
4030 {
4031 extract_actual_join_clauses(joinrestrictclauses,
4032 best_path->path.parent->relids,
4033 &joinclauses, &otherclauses);
4034 }
4035 else
4036 {
4037 /* We can treat all clauses alike for an inner join */
4038 joinclauses = extract_actual_clauses(joinrestrictclauses, false);
4039 otherclauses = NIL;
4040 }
4041
4042 /* Replace any outer-relation variables with nestloop params */
4043 if (best_path->path.param_info)
4044 {
4045 joinclauses = (List *)
4046 replace_nestloop_params(root, (Node *) joinclauses);
4047 otherclauses = (List *)
4048 replace_nestloop_params(root, (Node *) otherclauses);
4049 }
4050
4051 /*
4052 * Identify any nestloop parameters that should be supplied by this join
4053 * node, and remove them from root->curOuterParams.
4054 */
4055 outerrelids = best_path->outerjoinpath->parent->relids;
4056 nestParams = identify_current_nestloop_params(root, outerrelids);
4057
4058 join_plan = make_nestloop(tlist,
4059 joinclauses,
4060 otherclauses,
4061 nestParams,
4062 outer_plan,
4063 inner_plan,
4064 best_path->jointype,
4065 best_path->inner_unique);
4066
4067 copy_generic_path_info(&join_plan->join.plan, &best_path->path);
4068
4069 return join_plan;
4070 }
4071
4072 static MergeJoin *
create_mergejoin_plan(PlannerInfo * root,MergePath * best_path)4073 create_mergejoin_plan(PlannerInfo *root,
4074 MergePath *best_path)
4075 {
4076 MergeJoin *join_plan;
4077 Plan *outer_plan;
4078 Plan *inner_plan;
4079 List *tlist = build_path_tlist(root, &best_path->jpath.path);
4080 List *joinclauses;
4081 List *otherclauses;
4082 List *mergeclauses;
4083 List *outerpathkeys;
4084 List *innerpathkeys;
4085 int nClauses;
4086 Oid *mergefamilies;
4087 Oid *mergecollations;
4088 int *mergestrategies;
4089 bool *mergenullsfirst;
4090 PathKey *opathkey;
4091 EquivalenceClass *opeclass;
4092 int i;
4093 ListCell *lc;
4094 ListCell *lop;
4095 ListCell *lip;
4096 Path *outer_path = best_path->jpath.outerjoinpath;
4097 Path *inner_path = best_path->jpath.innerjoinpath;
4098
4099 /*
4100 * MergeJoin can project, so we don't have to demand exact tlists from the
4101 * inputs. However, if we're intending to sort an input's result, it's
4102 * best to request a small tlist so we aren't sorting more data than
4103 * necessary.
4104 */
4105 outer_plan = create_plan_recurse(root, best_path->jpath.outerjoinpath,
4106 (best_path->outersortkeys != NIL) ? CP_SMALL_TLIST : 0);
4107
4108 inner_plan = create_plan_recurse(root, best_path->jpath.innerjoinpath,
4109 (best_path->innersortkeys != NIL) ? CP_SMALL_TLIST : 0);
4110
4111 /* Sort join qual clauses into best execution order */
4112 /* NB: do NOT reorder the mergeclauses */
4113 joinclauses = order_qual_clauses(root, best_path->jpath.joinrestrictinfo);
4114
4115 /* Get the join qual clauses (in plain expression form) */
4116 /* Any pseudoconstant clauses are ignored here */
4117 if (IS_OUTER_JOIN(best_path->jpath.jointype))
4118 {
4119 extract_actual_join_clauses(joinclauses,
4120 best_path->jpath.path.parent->relids,
4121 &joinclauses, &otherclauses);
4122 }
4123 else
4124 {
4125 /* We can treat all clauses alike for an inner join */
4126 joinclauses = extract_actual_clauses(joinclauses, false);
4127 otherclauses = NIL;
4128 }
4129
4130 /*
4131 * Remove the mergeclauses from the list of join qual clauses, leaving the
4132 * list of quals that must be checked as qpquals.
4133 */
4134 mergeclauses = get_actual_clauses(best_path->path_mergeclauses);
4135 joinclauses = list_difference(joinclauses, mergeclauses);
4136
4137 /*
4138 * Replace any outer-relation variables with nestloop params. There
4139 * should not be any in the mergeclauses.
4140 */
4141 if (best_path->jpath.path.param_info)
4142 {
4143 joinclauses = (List *)
4144 replace_nestloop_params(root, (Node *) joinclauses);
4145 otherclauses = (List *)
4146 replace_nestloop_params(root, (Node *) otherclauses);
4147 }
4148
4149 /*
4150 * Rearrange mergeclauses, if needed, so that the outer variable is always
4151 * on the left; mark the mergeclause restrictinfos with correct
4152 * outer_is_left status.
4153 */
4154 mergeclauses = get_switched_clauses(best_path->path_mergeclauses,
4155 best_path->jpath.outerjoinpath->parent->relids);
4156
4157 /*
4158 * Create explicit sort nodes for the outer and inner paths if necessary.
4159 */
4160 if (best_path->outersortkeys)
4161 {
4162 Relids outer_relids = outer_path->parent->relids;
4163 Sort *sort = make_sort_from_pathkeys(outer_plan,
4164 best_path->outersortkeys,
4165 outer_relids);
4166
4167 label_sort_with_costsize(root, sort, -1.0);
4168 outer_plan = (Plan *) sort;
4169 outerpathkeys = best_path->outersortkeys;
4170 }
4171 else
4172 outerpathkeys = best_path->jpath.outerjoinpath->pathkeys;
4173
4174 if (best_path->innersortkeys)
4175 {
4176 Relids inner_relids = inner_path->parent->relids;
4177 Sort *sort = make_sort_from_pathkeys(inner_plan,
4178 best_path->innersortkeys,
4179 inner_relids);
4180
4181 label_sort_with_costsize(root, sort, -1.0);
4182 inner_plan = (Plan *) sort;
4183 innerpathkeys = best_path->innersortkeys;
4184 }
4185 else
4186 innerpathkeys = best_path->jpath.innerjoinpath->pathkeys;
4187
4188 /*
4189 * If specified, add a materialize node to shield the inner plan from the
4190 * need to handle mark/restore.
4191 */
4192 if (best_path->materialize_inner)
4193 {
4194 Plan *matplan = (Plan *) make_material(inner_plan);
4195
4196 /*
4197 * We assume the materialize will not spill to disk, and therefore
4198 * charge just cpu_operator_cost per tuple. (Keep this estimate in
4199 * sync with final_cost_mergejoin.)
4200 */
4201 copy_plan_costsize(matplan, inner_plan);
4202 matplan->total_cost += cpu_operator_cost * matplan->plan_rows;
4203
4204 inner_plan = matplan;
4205 }
4206
4207 /*
4208 * Compute the opfamily/collation/strategy/nullsfirst arrays needed by the
4209 * executor. The information is in the pathkeys for the two inputs, but
4210 * we need to be careful about the possibility of mergeclauses sharing a
4211 * pathkey, as well as the possibility that the inner pathkeys are not in
4212 * an order matching the mergeclauses.
4213 */
4214 nClauses = list_length(mergeclauses);
4215 Assert(nClauses == list_length(best_path->path_mergeclauses));
4216 mergefamilies = (Oid *) palloc(nClauses * sizeof(Oid));
4217 mergecollations = (Oid *) palloc(nClauses * sizeof(Oid));
4218 mergestrategies = (int *) palloc(nClauses * sizeof(int));
4219 mergenullsfirst = (bool *) palloc(nClauses * sizeof(bool));
4220
4221 opathkey = NULL;
4222 opeclass = NULL;
4223 lop = list_head(outerpathkeys);
4224 lip = list_head(innerpathkeys);
4225 i = 0;
4226 foreach(lc, best_path->path_mergeclauses)
4227 {
4228 RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
4229 EquivalenceClass *oeclass;
4230 EquivalenceClass *ieclass;
4231 PathKey *ipathkey = NULL;
4232 EquivalenceClass *ipeclass = NULL;
4233 bool first_inner_match = false;
4234
4235 /* fetch outer/inner eclass from mergeclause */
4236 if (rinfo->outer_is_left)
4237 {
4238 oeclass = rinfo->left_ec;
4239 ieclass = rinfo->right_ec;
4240 }
4241 else
4242 {
4243 oeclass = rinfo->right_ec;
4244 ieclass = rinfo->left_ec;
4245 }
4246 Assert(oeclass != NULL);
4247 Assert(ieclass != NULL);
4248
4249 /*
4250 * We must identify the pathkey elements associated with this clause
4251 * by matching the eclasses (which should give a unique match, since
4252 * the pathkey lists should be canonical). In typical cases the merge
4253 * clauses are one-to-one with the pathkeys, but when dealing with
4254 * partially redundant query conditions, things are more complicated.
4255 *
4256 * lop and lip reference the first as-yet-unmatched pathkey elements.
4257 * If they're NULL then all pathkey elements have been matched.
4258 *
4259 * The ordering of the outer pathkeys should match the mergeclauses,
4260 * by construction (see find_mergeclauses_for_outer_pathkeys()). There
4261 * could be more than one mergeclause for the same outer pathkey, but
4262 * no pathkey may be entirely skipped over.
4263 */
4264 if (oeclass != opeclass) /* multiple matches are not interesting */
4265 {
4266 /* doesn't match the current opathkey, so must match the next */
4267 if (lop == NULL)
4268 elog(ERROR, "outer pathkeys do not match mergeclauses");
4269 opathkey = (PathKey *) lfirst(lop);
4270 opeclass = opathkey->pk_eclass;
4271 lop = lnext(lop);
4272 if (oeclass != opeclass)
4273 elog(ERROR, "outer pathkeys do not match mergeclauses");
4274 }
4275
4276 /*
4277 * The inner pathkeys likewise should not have skipped-over keys, but
4278 * it's possible for a mergeclause to reference some earlier inner
4279 * pathkey if we had redundant pathkeys. For example we might have
4280 * mergeclauses like "o.a = i.x AND o.b = i.y AND o.c = i.x". The
4281 * implied inner ordering is then "ORDER BY x, y, x", but the pathkey
4282 * mechanism drops the second sort by x as redundant, and this code
4283 * must cope.
4284 *
4285 * It's also possible for the implied inner-rel ordering to be like
4286 * "ORDER BY x, y, x DESC". We still drop the second instance of x as
4287 * redundant; but this means that the sort ordering of a redundant
4288 * inner pathkey should not be considered significant. So we must
4289 * detect whether this is the first clause matching an inner pathkey.
4290 */
4291 if (lip)
4292 {
4293 ipathkey = (PathKey *) lfirst(lip);
4294 ipeclass = ipathkey->pk_eclass;
4295 if (ieclass == ipeclass)
4296 {
4297 /* successful first match to this inner pathkey */
4298 lip = lnext(lip);
4299 first_inner_match = true;
4300 }
4301 }
4302 if (!first_inner_match)
4303 {
4304 /* redundant clause ... must match something before lip */
4305 ListCell *l2;
4306
4307 foreach(l2, innerpathkeys)
4308 {
4309 if (l2 == lip)
4310 break;
4311 ipathkey = (PathKey *) lfirst(l2);
4312 ipeclass = ipathkey->pk_eclass;
4313 if (ieclass == ipeclass)
4314 break;
4315 }
4316 if (ieclass != ipeclass)
4317 elog(ERROR, "inner pathkeys do not match mergeclauses");
4318 }
4319
4320 /*
4321 * The pathkeys should always match each other as to opfamily and
4322 * collation (which affect equality), but if we're considering a
4323 * redundant inner pathkey, its sort ordering might not match. In
4324 * such cases we may ignore the inner pathkey's sort ordering and use
4325 * the outer's. (In effect, we're lying to the executor about the
4326 * sort direction of this inner column, but it does not matter since
4327 * the run-time row comparisons would only reach this column when
4328 * there's equality for the earlier column containing the same eclass.
4329 * There could be only one value in this column for the range of inner
4330 * rows having a given value in the earlier column, so it does not
4331 * matter which way we imagine this column to be ordered.) But a
4332 * non-redundant inner pathkey had better match outer's ordering too.
4333 */
4334 if (opathkey->pk_opfamily != ipathkey->pk_opfamily ||
4335 opathkey->pk_eclass->ec_collation != ipathkey->pk_eclass->ec_collation)
4336 elog(ERROR, "left and right pathkeys do not match in mergejoin");
4337 if (first_inner_match &&
4338 (opathkey->pk_strategy != ipathkey->pk_strategy ||
4339 opathkey->pk_nulls_first != ipathkey->pk_nulls_first))
4340 elog(ERROR, "left and right pathkeys do not match in mergejoin");
4341
4342 /* OK, save info for executor */
4343 mergefamilies[i] = opathkey->pk_opfamily;
4344 mergecollations[i] = opathkey->pk_eclass->ec_collation;
4345 mergestrategies[i] = opathkey->pk_strategy;
4346 mergenullsfirst[i] = opathkey->pk_nulls_first;
4347 i++;
4348 }
4349
4350 /*
4351 * Note: it is not an error if we have additional pathkey elements (i.e.,
4352 * lop or lip isn't NULL here). The input paths might be better-sorted
4353 * than we need for the current mergejoin.
4354 */
4355
4356 /*
4357 * Now we can build the mergejoin node.
4358 */
4359 join_plan = make_mergejoin(tlist,
4360 joinclauses,
4361 otherclauses,
4362 mergeclauses,
4363 mergefamilies,
4364 mergecollations,
4365 mergestrategies,
4366 mergenullsfirst,
4367 outer_plan,
4368 inner_plan,
4369 best_path->jpath.jointype,
4370 best_path->jpath.inner_unique,
4371 best_path->skip_mark_restore);
4372
4373 /* Costs of sort and material steps are included in path cost already */
4374 copy_generic_path_info(&join_plan->join.plan, &best_path->jpath.path);
4375
4376 return join_plan;
4377 }
4378
4379 static HashJoin *
create_hashjoin_plan(PlannerInfo * root,HashPath * best_path)4380 create_hashjoin_plan(PlannerInfo *root,
4381 HashPath *best_path)
4382 {
4383 HashJoin *join_plan;
4384 Hash *hash_plan;
4385 Plan *outer_plan;
4386 Plan *inner_plan;
4387 List *tlist = build_path_tlist(root, &best_path->jpath.path);
4388 List *joinclauses;
4389 List *otherclauses;
4390 List *hashclauses;
4391 List *hashoperators = NIL;
4392 List *hashcollations = NIL;
4393 List *inner_hashkeys = NIL;
4394 List *outer_hashkeys = NIL;
4395 Oid skewTable = InvalidOid;
4396 AttrNumber skewColumn = InvalidAttrNumber;
4397 bool skewInherit = false;
4398 ListCell *lc;
4399
4400 /*
4401 * HashJoin can project, so we don't have to demand exact tlists from the
4402 * inputs. However, it's best to request a small tlist from the inner
4403 * side, so that we aren't storing more data than necessary. Likewise, if
4404 * we anticipate batching, request a small tlist from the outer side so
4405 * that we don't put extra data in the outer batch files.
4406 */
4407 outer_plan = create_plan_recurse(root, best_path->jpath.outerjoinpath,
4408 (best_path->num_batches > 1) ? CP_SMALL_TLIST : 0);
4409
4410 inner_plan = create_plan_recurse(root, best_path->jpath.innerjoinpath,
4411 CP_SMALL_TLIST);
4412
4413 /* Sort join qual clauses into best execution order */
4414 joinclauses = order_qual_clauses(root, best_path->jpath.joinrestrictinfo);
4415 /* There's no point in sorting the hash clauses ... */
4416
4417 /* Get the join qual clauses (in plain expression form) */
4418 /* Any pseudoconstant clauses are ignored here */
4419 if (IS_OUTER_JOIN(best_path->jpath.jointype))
4420 {
4421 extract_actual_join_clauses(joinclauses,
4422 best_path->jpath.path.parent->relids,
4423 &joinclauses, &otherclauses);
4424 }
4425 else
4426 {
4427 /* We can treat all clauses alike for an inner join */
4428 joinclauses = extract_actual_clauses(joinclauses, false);
4429 otherclauses = NIL;
4430 }
4431
4432 /*
4433 * Remove the hashclauses from the list of join qual clauses, leaving the
4434 * list of quals that must be checked as qpquals.
4435 */
4436 hashclauses = get_actual_clauses(best_path->path_hashclauses);
4437 joinclauses = list_difference(joinclauses, hashclauses);
4438
4439 /*
4440 * Replace any outer-relation variables with nestloop params. There
4441 * should not be any in the hashclauses.
4442 */
4443 if (best_path->jpath.path.param_info)
4444 {
4445 joinclauses = (List *)
4446 replace_nestloop_params(root, (Node *) joinclauses);
4447 otherclauses = (List *)
4448 replace_nestloop_params(root, (Node *) otherclauses);
4449 }
4450
4451 /*
4452 * Rearrange hashclauses, if needed, so that the outer variable is always
4453 * on the left.
4454 */
4455 hashclauses = get_switched_clauses(best_path->path_hashclauses,
4456 best_path->jpath.outerjoinpath->parent->relids);
4457
4458 /*
4459 * If there is a single join clause and we can identify the outer variable
4460 * as a simple column reference, supply its identity for possible use in
4461 * skew optimization. (Note: in principle we could do skew optimization
4462 * with multiple join clauses, but we'd have to be able to determine the
4463 * most common combinations of outer values, which we don't currently have
4464 * enough stats for.)
4465 */
4466 if (list_length(hashclauses) == 1)
4467 {
4468 OpExpr *clause = (OpExpr *) linitial(hashclauses);
4469 Node *node;
4470
4471 Assert(is_opclause(clause));
4472 node = (Node *) linitial(clause->args);
4473 if (IsA(node, RelabelType))
4474 node = (Node *) ((RelabelType *) node)->arg;
4475 if (IsA(node, Var))
4476 {
4477 Var *var = (Var *) node;
4478 RangeTblEntry *rte;
4479
4480 rte = root->simple_rte_array[var->varno];
4481 if (rte->rtekind == RTE_RELATION)
4482 {
4483 skewTable = rte->relid;
4484 skewColumn = var->varattno;
4485 skewInherit = rte->inh;
4486 }
4487 }
4488 }
4489
4490 /*
4491 * Collect hash related information. The hashed expressions are
4492 * deconstructed into outer/inner expressions, so they can be computed
4493 * separately (inner expressions are used to build the hashtable via Hash,
4494 * outer expressions to perform lookups of tuples from HashJoin's outer
4495 * plan in the hashtable). Also collect operator information necessary to
4496 * build the hashtable.
4497 */
4498 foreach(lc, hashclauses)
4499 {
4500 OpExpr *hclause = lfirst_node(OpExpr, lc);
4501
4502 hashoperators = lappend_oid(hashoperators, hclause->opno);
4503 hashcollations = lappend_oid(hashcollations, hclause->inputcollid);
4504 outer_hashkeys = lappend(outer_hashkeys, linitial(hclause->args));
4505 inner_hashkeys = lappend(inner_hashkeys, lsecond(hclause->args));
4506 }
4507
4508 /*
4509 * Build the hash node and hash join node.
4510 */
4511 hash_plan = make_hash(inner_plan,
4512 inner_hashkeys,
4513 skewTable,
4514 skewColumn,
4515 skewInherit);
4516
4517 /*
4518 * Set Hash node's startup & total costs equal to total cost of input
4519 * plan; this only affects EXPLAIN display not decisions.
4520 */
4521 copy_plan_costsize(&hash_plan->plan, inner_plan);
4522 hash_plan->plan.startup_cost = hash_plan->plan.total_cost;
4523
4524 /*
4525 * If parallel-aware, the executor will also need an estimate of the total
4526 * number of rows expected from all participants so that it can size the
4527 * shared hash table.
4528 */
4529 if (best_path->jpath.path.parallel_aware)
4530 {
4531 hash_plan->plan.parallel_aware = true;
4532 hash_plan->rows_total = best_path->inner_rows_total;
4533 }
4534
4535 join_plan = make_hashjoin(tlist,
4536 joinclauses,
4537 otherclauses,
4538 hashclauses,
4539 hashoperators,
4540 hashcollations,
4541 outer_hashkeys,
4542 outer_plan,
4543 (Plan *) hash_plan,
4544 best_path->jpath.jointype,
4545 best_path->jpath.inner_unique);
4546
4547 copy_generic_path_info(&join_plan->join.plan, &best_path->jpath.path);
4548
4549 return join_plan;
4550 }
4551
4552
4553 /*****************************************************************************
4554 *
4555 * SUPPORTING ROUTINES
4556 *
4557 *****************************************************************************/
4558
4559 /*
4560 * replace_nestloop_params
4561 * Replace outer-relation Vars and PlaceHolderVars in the given expression
4562 * with nestloop Params
4563 *
4564 * All Vars and PlaceHolderVars belonging to the relation(s) identified by
4565 * root->curOuterRels are replaced by Params, and entries are added to
4566 * root->curOuterParams if not already present.
4567 */
4568 static Node *
replace_nestloop_params(PlannerInfo * root,Node * expr)4569 replace_nestloop_params(PlannerInfo *root, Node *expr)
4570 {
4571 /* No setup needed for tree walk, so away we go */
4572 return replace_nestloop_params_mutator(expr, root);
4573 }
4574
4575 static Node *
replace_nestloop_params_mutator(Node * node,PlannerInfo * root)4576 replace_nestloop_params_mutator(Node *node, PlannerInfo *root)
4577 {
4578 if (node == NULL)
4579 return NULL;
4580 if (IsA(node, Var))
4581 {
4582 Var *var = (Var *) node;
4583
4584 /* Upper-level Vars should be long gone at this point */
4585 Assert(var->varlevelsup == 0);
4586 /* If not to be replaced, we can just return the Var unmodified */
4587 if (!bms_is_member(var->varno, root->curOuterRels))
4588 return node;
4589 /* Replace the Var with a nestloop Param */
4590 return (Node *) replace_nestloop_param_var(root, var);
4591 }
4592 if (IsA(node, PlaceHolderVar))
4593 {
4594 PlaceHolderVar *phv = (PlaceHolderVar *) node;
4595
4596 /* Upper-level PlaceHolderVars should be long gone at this point */
4597 Assert(phv->phlevelsup == 0);
4598
4599 /*
4600 * Check whether we need to replace the PHV. We use bms_overlap as a
4601 * cheap/quick test to see if the PHV might be evaluated in the outer
4602 * rels, and then grab its PlaceHolderInfo to tell for sure.
4603 */
4604 if (!bms_overlap(phv->phrels, root->curOuterRels) ||
4605 !bms_is_subset(find_placeholder_info(root, phv, false)->ph_eval_at,
4606 root->curOuterRels))
4607 {
4608 /*
4609 * We can't replace the whole PHV, but we might still need to
4610 * replace Vars or PHVs within its expression, in case it ends up
4611 * actually getting evaluated here. (It might get evaluated in
4612 * this plan node, or some child node; in the latter case we don't
4613 * really need to process the expression here, but we haven't got
4614 * enough info to tell if that's the case.) Flat-copy the PHV
4615 * node and then recurse on its expression.
4616 *
4617 * Note that after doing this, we might have different
4618 * representations of the contents of the same PHV in different
4619 * parts of the plan tree. This is OK because equal() will just
4620 * match on phid/phlevelsup, so setrefs.c will still recognize an
4621 * upper-level reference to a lower-level copy of the same PHV.
4622 */
4623 PlaceHolderVar *newphv = makeNode(PlaceHolderVar);
4624
4625 memcpy(newphv, phv, sizeof(PlaceHolderVar));
4626 newphv->phexpr = (Expr *)
4627 replace_nestloop_params_mutator((Node *) phv->phexpr,
4628 root);
4629 return (Node *) newphv;
4630 }
4631 /* Replace the PlaceHolderVar with a nestloop Param */
4632 return (Node *) replace_nestloop_param_placeholdervar(root, phv);
4633 }
4634 return expression_tree_mutator(node,
4635 replace_nestloop_params_mutator,
4636 (void *) root);
4637 }
4638
4639 /*
4640 * fix_indexqual_references
4641 * Adjust indexqual clauses to the form the executor's indexqual
4642 * machinery needs.
4643 *
4644 * We have three tasks here:
4645 * * Select the actual qual clauses out of the input IndexClause list,
4646 * and remove RestrictInfo nodes from the qual clauses.
4647 * * Replace any outer-relation Var or PHV nodes with nestloop Params.
4648 * (XXX eventually, that responsibility should go elsewhere?)
4649 * * Index keys must be represented by Var nodes with varattno set to the
4650 * index's attribute number, not the attribute number in the original rel.
4651 *
4652 * *stripped_indexquals_p receives a list of the actual qual clauses.
4653 *
4654 * *fixed_indexquals_p receives a list of the adjusted quals. This is a copy
4655 * that shares no substructure with the original; this is needed in case there
4656 * are subplans in it (we need two separate copies of the subplan tree, or
4657 * things will go awry).
4658 */
4659 static void
fix_indexqual_references(PlannerInfo * root,IndexPath * index_path,List ** stripped_indexquals_p,List ** fixed_indexquals_p)4660 fix_indexqual_references(PlannerInfo *root, IndexPath *index_path,
4661 List **stripped_indexquals_p, List **fixed_indexquals_p)
4662 {
4663 IndexOptInfo *index = index_path->indexinfo;
4664 List *stripped_indexquals;
4665 List *fixed_indexquals;
4666 ListCell *lc;
4667
4668 stripped_indexquals = fixed_indexquals = NIL;
4669
4670 foreach(lc, index_path->indexclauses)
4671 {
4672 IndexClause *iclause = lfirst_node(IndexClause, lc);
4673 int indexcol = iclause->indexcol;
4674 ListCell *lc2;
4675
4676 foreach(lc2, iclause->indexquals)
4677 {
4678 RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc2);
4679 Node *clause = (Node *) rinfo->clause;
4680
4681 stripped_indexquals = lappend(stripped_indexquals, clause);
4682 clause = fix_indexqual_clause(root, index, indexcol,
4683 clause, iclause->indexcols);
4684 fixed_indexquals = lappend(fixed_indexquals, clause);
4685 }
4686 }
4687
4688 *stripped_indexquals_p = stripped_indexquals;
4689 *fixed_indexquals_p = fixed_indexquals;
4690 }
4691
4692 /*
4693 * fix_indexorderby_references
4694 * Adjust indexorderby clauses to the form the executor's index
4695 * machinery needs.
4696 *
4697 * This is a simplified version of fix_indexqual_references. The input is
4698 * bare clauses and a separate indexcol list, instead of IndexClauses.
4699 */
4700 static List *
fix_indexorderby_references(PlannerInfo * root,IndexPath * index_path)4701 fix_indexorderby_references(PlannerInfo *root, IndexPath *index_path)
4702 {
4703 IndexOptInfo *index = index_path->indexinfo;
4704 List *fixed_indexorderbys;
4705 ListCell *lcc,
4706 *lci;
4707
4708 fixed_indexorderbys = NIL;
4709
4710 forboth(lcc, index_path->indexorderbys, lci, index_path->indexorderbycols)
4711 {
4712 Node *clause = (Node *) lfirst(lcc);
4713 int indexcol = lfirst_int(lci);
4714
4715 clause = fix_indexqual_clause(root, index, indexcol, clause, NIL);
4716 fixed_indexorderbys = lappend(fixed_indexorderbys, clause);
4717 }
4718
4719 return fixed_indexorderbys;
4720 }
4721
4722 /*
4723 * fix_indexqual_clause
4724 * Convert a single indexqual clause to the form needed by the executor.
4725 *
4726 * We replace nestloop params here, and replace the index key variables
4727 * or expressions by index Var nodes.
4728 */
4729 static Node *
fix_indexqual_clause(PlannerInfo * root,IndexOptInfo * index,int indexcol,Node * clause,List * indexcolnos)4730 fix_indexqual_clause(PlannerInfo *root, IndexOptInfo *index, int indexcol,
4731 Node *clause, List *indexcolnos)
4732 {
4733 /*
4734 * Replace any outer-relation variables with nestloop params.
4735 *
4736 * This also makes a copy of the clause, so it's safe to modify it
4737 * in-place below.
4738 */
4739 clause = replace_nestloop_params(root, clause);
4740
4741 if (IsA(clause, OpExpr))
4742 {
4743 OpExpr *op = (OpExpr *) clause;
4744
4745 /* Replace the indexkey expression with an index Var. */
4746 linitial(op->args) = fix_indexqual_operand(linitial(op->args),
4747 index,
4748 indexcol);
4749 }
4750 else if (IsA(clause, RowCompareExpr))
4751 {
4752 RowCompareExpr *rc = (RowCompareExpr *) clause;
4753 ListCell *lca,
4754 *lcai;
4755
4756 /* Replace the indexkey expressions with index Vars. */
4757 Assert(list_length(rc->largs) == list_length(indexcolnos));
4758 forboth(lca, rc->largs, lcai, indexcolnos)
4759 {
4760 lfirst(lca) = fix_indexqual_operand(lfirst(lca),
4761 index,
4762 lfirst_int(lcai));
4763 }
4764 }
4765 else if (IsA(clause, ScalarArrayOpExpr))
4766 {
4767 ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) clause;
4768
4769 /* Replace the indexkey expression with an index Var. */
4770 linitial(saop->args) = fix_indexqual_operand(linitial(saop->args),
4771 index,
4772 indexcol);
4773 }
4774 else if (IsA(clause, NullTest))
4775 {
4776 NullTest *nt = (NullTest *) clause;
4777
4778 /* Replace the indexkey expression with an index Var. */
4779 nt->arg = (Expr *) fix_indexqual_operand((Node *) nt->arg,
4780 index,
4781 indexcol);
4782 }
4783 else
4784 elog(ERROR, "unsupported indexqual type: %d",
4785 (int) nodeTag(clause));
4786
4787 return clause;
4788 }
4789
4790 /*
4791 * fix_indexqual_operand
4792 * Convert an indexqual expression to a Var referencing the index column.
4793 *
4794 * We represent index keys by Var nodes having varno == INDEX_VAR and varattno
4795 * equal to the index's attribute number (index column position).
4796 *
4797 * Most of the code here is just for sanity cross-checking that the given
4798 * expression actually matches the index column it's claimed to.
4799 */
4800 static Node *
fix_indexqual_operand(Node * node,IndexOptInfo * index,int indexcol)4801 fix_indexqual_operand(Node *node, IndexOptInfo *index, int indexcol)
4802 {
4803 Var *result;
4804 int pos;
4805 ListCell *indexpr_item;
4806
4807 /*
4808 * Remove any binary-compatible relabeling of the indexkey
4809 */
4810 if (IsA(node, RelabelType))
4811 node = (Node *) ((RelabelType *) node)->arg;
4812
4813 Assert(indexcol >= 0 && indexcol < index->ncolumns);
4814
4815 if (index->indexkeys[indexcol] != 0)
4816 {
4817 /* It's a simple index column */
4818 if (IsA(node, Var) &&
4819 ((Var *) node)->varno == index->rel->relid &&
4820 ((Var *) node)->varattno == index->indexkeys[indexcol])
4821 {
4822 result = (Var *) copyObject(node);
4823 result->varno = INDEX_VAR;
4824 result->varattno = indexcol + 1;
4825 return (Node *) result;
4826 }
4827 else
4828 elog(ERROR, "index key does not match expected index column");
4829 }
4830
4831 /* It's an index expression, so find and cross-check the expression */
4832 indexpr_item = list_head(index->indexprs);
4833 for (pos = 0; pos < index->ncolumns; pos++)
4834 {
4835 if (index->indexkeys[pos] == 0)
4836 {
4837 if (indexpr_item == NULL)
4838 elog(ERROR, "too few entries in indexprs list");
4839 if (pos == indexcol)
4840 {
4841 Node *indexkey;
4842
4843 indexkey = (Node *) lfirst(indexpr_item);
4844 if (indexkey && IsA(indexkey, RelabelType))
4845 indexkey = (Node *) ((RelabelType *) indexkey)->arg;
4846 if (equal(node, indexkey))
4847 {
4848 result = makeVar(INDEX_VAR, indexcol + 1,
4849 exprType(lfirst(indexpr_item)), -1,
4850 exprCollation(lfirst(indexpr_item)),
4851 0);
4852 return (Node *) result;
4853 }
4854 else
4855 elog(ERROR, "index key does not match expected index column");
4856 }
4857 indexpr_item = lnext(indexpr_item);
4858 }
4859 }
4860
4861 /* Oops... */
4862 elog(ERROR, "index key does not match expected index column");
4863 return NULL; /* keep compiler quiet */
4864 }
4865
4866 /*
4867 * get_switched_clauses
4868 * Given a list of merge or hash joinclauses (as RestrictInfo nodes),
4869 * extract the bare clauses, and rearrange the elements within the
4870 * clauses, if needed, so the outer join variable is on the left and
4871 * the inner is on the right. The original clause data structure is not
4872 * touched; a modified list is returned. We do, however, set the transient
4873 * outer_is_left field in each RestrictInfo to show which side was which.
4874 */
4875 static List *
get_switched_clauses(List * clauses,Relids outerrelids)4876 get_switched_clauses(List *clauses, Relids outerrelids)
4877 {
4878 List *t_list = NIL;
4879 ListCell *l;
4880
4881 foreach(l, clauses)
4882 {
4883 RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(l);
4884 OpExpr *clause = (OpExpr *) restrictinfo->clause;
4885
4886 Assert(is_opclause(clause));
4887 if (bms_is_subset(restrictinfo->right_relids, outerrelids))
4888 {
4889 /*
4890 * Duplicate just enough of the structure to allow commuting the
4891 * clause without changing the original list. Could use
4892 * copyObject, but a complete deep copy is overkill.
4893 */
4894 OpExpr *temp = makeNode(OpExpr);
4895
4896 temp->opno = clause->opno;
4897 temp->opfuncid = InvalidOid;
4898 temp->opresulttype = clause->opresulttype;
4899 temp->opretset = clause->opretset;
4900 temp->opcollid = clause->opcollid;
4901 temp->inputcollid = clause->inputcollid;
4902 temp->args = list_copy(clause->args);
4903 temp->location = clause->location;
4904 /* Commute it --- note this modifies the temp node in-place. */
4905 CommuteOpExpr(temp);
4906 t_list = lappend(t_list, temp);
4907 restrictinfo->outer_is_left = false;
4908 }
4909 else
4910 {
4911 Assert(bms_is_subset(restrictinfo->left_relids, outerrelids));
4912 t_list = lappend(t_list, clause);
4913 restrictinfo->outer_is_left = true;
4914 }
4915 }
4916 return t_list;
4917 }
4918
4919 /*
4920 * order_qual_clauses
4921 * Given a list of qual clauses that will all be evaluated at the same
4922 * plan node, sort the list into the order we want to check the quals
4923 * in at runtime.
4924 *
4925 * When security barrier quals are used in the query, we may have quals with
4926 * different security levels in the list. Quals of lower security_level
4927 * must go before quals of higher security_level, except that we can grant
4928 * exceptions to move up quals that are leakproof. When security level
4929 * doesn't force the decision, we prefer to order clauses by estimated
4930 * execution cost, cheapest first.
4931 *
4932 * Ideally the order should be driven by a combination of execution cost and
4933 * selectivity, but it's not immediately clear how to account for both,
4934 * and given the uncertainty of the estimates the reliability of the decisions
4935 * would be doubtful anyway. So we just order by security level then
4936 * estimated per-tuple cost, being careful not to change the order when
4937 * (as is often the case) the estimates are identical.
4938 *
4939 * Although this will work on either bare clauses or RestrictInfos, it's
4940 * much faster to apply it to RestrictInfos, since it can re-use cost
4941 * information that is cached in RestrictInfos. XXX in the bare-clause
4942 * case, we are also not able to apply security considerations. That is
4943 * all right for the moment, because the bare-clause case doesn't occur
4944 * anywhere that barrier quals could be present, but it would be better to
4945 * get rid of it.
4946 *
4947 * Note: some callers pass lists that contain entries that will later be
4948 * removed; this is the easiest way to let this routine see RestrictInfos
4949 * instead of bare clauses. This is another reason why trying to consider
4950 * selectivity in the ordering would likely do the wrong thing.
4951 */
4952 static List *
order_qual_clauses(PlannerInfo * root,List * clauses)4953 order_qual_clauses(PlannerInfo *root, List *clauses)
4954 {
4955 typedef struct
4956 {
4957 Node *clause;
4958 Cost cost;
4959 Index security_level;
4960 } QualItem;
4961 int nitems = list_length(clauses);
4962 QualItem *items;
4963 ListCell *lc;
4964 int i;
4965 List *result;
4966
4967 /* No need to work hard for 0 or 1 clause */
4968 if (nitems <= 1)
4969 return clauses;
4970
4971 /*
4972 * Collect the items and costs into an array. This is to avoid repeated
4973 * cost_qual_eval work if the inputs aren't RestrictInfos.
4974 */
4975 items = (QualItem *) palloc(nitems * sizeof(QualItem));
4976 i = 0;
4977 foreach(lc, clauses)
4978 {
4979 Node *clause = (Node *) lfirst(lc);
4980 QualCost qcost;
4981
4982 cost_qual_eval_node(&qcost, clause, root);
4983 items[i].clause = clause;
4984 items[i].cost = qcost.per_tuple;
4985 if (IsA(clause, RestrictInfo))
4986 {
4987 RestrictInfo *rinfo = (RestrictInfo *) clause;
4988
4989 /*
4990 * If a clause is leakproof, it doesn't have to be constrained by
4991 * its nominal security level. If it's also reasonably cheap
4992 * (here defined as 10X cpu_operator_cost), pretend it has
4993 * security_level 0, which will allow it to go in front of
4994 * more-expensive quals of lower security levels. Of course, that
4995 * will also force it to go in front of cheaper quals of its own
4996 * security level, which is not so great, but we can alleviate
4997 * that risk by applying the cost limit cutoff.
4998 */
4999 if (rinfo->leakproof && items[i].cost < 10 * cpu_operator_cost)
5000 items[i].security_level = 0;
5001 else
5002 items[i].security_level = rinfo->security_level;
5003 }
5004 else
5005 items[i].security_level = 0;
5006 i++;
5007 }
5008
5009 /*
5010 * Sort. We don't use qsort() because it's not guaranteed stable for
5011 * equal keys. The expected number of entries is small enough that a
5012 * simple insertion sort should be good enough.
5013 */
5014 for (i = 1; i < nitems; i++)
5015 {
5016 QualItem newitem = items[i];
5017 int j;
5018
5019 /* insert newitem into the already-sorted subarray */
5020 for (j = i; j > 0; j--)
5021 {
5022 QualItem *olditem = &items[j - 1];
5023
5024 if (newitem.security_level > olditem->security_level ||
5025 (newitem.security_level == olditem->security_level &&
5026 newitem.cost >= olditem->cost))
5027 break;
5028 items[j] = *olditem;
5029 }
5030 items[j] = newitem;
5031 }
5032
5033 /* Convert back to a list */
5034 result = NIL;
5035 for (i = 0; i < nitems; i++)
5036 result = lappend(result, items[i].clause);
5037
5038 return result;
5039 }
5040
5041 /*
5042 * Copy cost and size info from a Path node to the Plan node created from it.
5043 * The executor usually won't use this info, but it's needed by EXPLAIN.
5044 * Also copy the parallel-related flags, which the executor *will* use.
5045 */
5046 static void
copy_generic_path_info(Plan * dest,Path * src)5047 copy_generic_path_info(Plan *dest, Path *src)
5048 {
5049 dest->startup_cost = src->startup_cost;
5050 dest->total_cost = src->total_cost;
5051 dest->plan_rows = src->rows;
5052 dest->plan_width = src->pathtarget->width;
5053 dest->parallel_aware = src->parallel_aware;
5054 dest->parallel_safe = src->parallel_safe;
5055 }
5056
5057 /*
5058 * Copy cost and size info from a lower plan node to an inserted node.
5059 * (Most callers alter the info after copying it.)
5060 */
5061 static void
copy_plan_costsize(Plan * dest,Plan * src)5062 copy_plan_costsize(Plan *dest, Plan *src)
5063 {
5064 dest->startup_cost = src->startup_cost;
5065 dest->total_cost = src->total_cost;
5066 dest->plan_rows = src->plan_rows;
5067 dest->plan_width = src->plan_width;
5068 /* Assume the inserted node is not parallel-aware. */
5069 dest->parallel_aware = false;
5070 /* Assume the inserted node is parallel-safe, if child plan is. */
5071 dest->parallel_safe = src->parallel_safe;
5072 }
5073
5074 /*
5075 * Some places in this file build Sort nodes that don't have a directly
5076 * corresponding Path node. The cost of the sort is, or should have been,
5077 * included in the cost of the Path node we're working from, but since it's
5078 * not split out, we have to re-figure it using cost_sort(). This is just
5079 * to label the Sort node nicely for EXPLAIN.
5080 *
5081 * limit_tuples is as for cost_sort (in particular, pass -1 if no limit)
5082 */
5083 static void
label_sort_with_costsize(PlannerInfo * root,Sort * plan,double limit_tuples)5084 label_sort_with_costsize(PlannerInfo *root, Sort *plan, double limit_tuples)
5085 {
5086 Plan *lefttree = plan->plan.lefttree;
5087 Path sort_path; /* dummy for result of cost_sort */
5088
5089 cost_sort(&sort_path, root, NIL,
5090 lefttree->total_cost,
5091 lefttree->plan_rows,
5092 lefttree->plan_width,
5093 0.0,
5094 work_mem,
5095 limit_tuples);
5096 plan->plan.startup_cost = sort_path.startup_cost;
5097 plan->plan.total_cost = sort_path.total_cost;
5098 plan->plan.plan_rows = lefttree->plan_rows;
5099 plan->plan.plan_width = lefttree->plan_width;
5100 plan->plan.parallel_aware = false;
5101 plan->plan.parallel_safe = lefttree->parallel_safe;
5102 }
5103
5104 /*
5105 * bitmap_subplan_mark_shared
5106 * Set isshared flag in bitmap subplan so that it will be created in
5107 * shared memory.
5108 */
5109 static void
bitmap_subplan_mark_shared(Plan * plan)5110 bitmap_subplan_mark_shared(Plan *plan)
5111 {
5112 if (IsA(plan, BitmapAnd))
5113 bitmap_subplan_mark_shared(
5114 linitial(((BitmapAnd *) plan)->bitmapplans));
5115 else if (IsA(plan, BitmapOr))
5116 {
5117 ((BitmapOr *) plan)->isshared = true;
5118 bitmap_subplan_mark_shared(
5119 linitial(((BitmapOr *) plan)->bitmapplans));
5120 }
5121 else if (IsA(plan, BitmapIndexScan))
5122 ((BitmapIndexScan *) plan)->isshared = true;
5123 else
5124 elog(ERROR, "unrecognized node type: %d", nodeTag(plan));
5125 }
5126
5127 /*****************************************************************************
5128 *
5129 * PLAN NODE BUILDING ROUTINES
5130 *
5131 * In general, these functions are not passed the original Path and therefore
5132 * leave it to the caller to fill in the cost/width fields from the Path,
5133 * typically by calling copy_generic_path_info(). This convention is
5134 * somewhat historical, but it does support a few places above where we build
5135 * a plan node without having an exactly corresponding Path node. Under no
5136 * circumstances should one of these functions do its own cost calculations,
5137 * as that would be redundant with calculations done while building Paths.
5138 *
5139 *****************************************************************************/
5140
5141 static SeqScan *
make_seqscan(List * qptlist,List * qpqual,Index scanrelid)5142 make_seqscan(List *qptlist,
5143 List *qpqual,
5144 Index scanrelid)
5145 {
5146 SeqScan *node = makeNode(SeqScan);
5147 Plan *plan = &node->plan;
5148
5149 plan->targetlist = qptlist;
5150 plan->qual = qpqual;
5151 plan->lefttree = NULL;
5152 plan->righttree = NULL;
5153 node->scanrelid = scanrelid;
5154
5155 return node;
5156 }
5157
5158 static SampleScan *
make_samplescan(List * qptlist,List * qpqual,Index scanrelid,TableSampleClause * tsc)5159 make_samplescan(List *qptlist,
5160 List *qpqual,
5161 Index scanrelid,
5162 TableSampleClause *tsc)
5163 {
5164 SampleScan *node = makeNode(SampleScan);
5165 Plan *plan = &node->scan.plan;
5166
5167 plan->targetlist = qptlist;
5168 plan->qual = qpqual;
5169 plan->lefttree = NULL;
5170 plan->righttree = NULL;
5171 node->scan.scanrelid = scanrelid;
5172 node->tablesample = tsc;
5173
5174 return node;
5175 }
5176
5177 static IndexScan *
make_indexscan(List * qptlist,List * qpqual,Index scanrelid,Oid indexid,List * indexqual,List * indexqualorig,List * indexorderby,List * indexorderbyorig,List * indexorderbyops,ScanDirection indexscandir)5178 make_indexscan(List *qptlist,
5179 List *qpqual,
5180 Index scanrelid,
5181 Oid indexid,
5182 List *indexqual,
5183 List *indexqualorig,
5184 List *indexorderby,
5185 List *indexorderbyorig,
5186 List *indexorderbyops,
5187 ScanDirection indexscandir)
5188 {
5189 IndexScan *node = makeNode(IndexScan);
5190 Plan *plan = &node->scan.plan;
5191
5192 plan->targetlist = qptlist;
5193 plan->qual = qpqual;
5194 plan->lefttree = NULL;
5195 plan->righttree = NULL;
5196 node->scan.scanrelid = scanrelid;
5197 node->indexid = indexid;
5198 node->indexqual = indexqual;
5199 node->indexqualorig = indexqualorig;
5200 node->indexorderby = indexorderby;
5201 node->indexorderbyorig = indexorderbyorig;
5202 node->indexorderbyops = indexorderbyops;
5203 node->indexorderdir = indexscandir;
5204
5205 return node;
5206 }
5207
5208 static IndexOnlyScan *
make_indexonlyscan(List * qptlist,List * qpqual,Index scanrelid,Oid indexid,List * indexqual,List * indexorderby,List * indextlist,ScanDirection indexscandir)5209 make_indexonlyscan(List *qptlist,
5210 List *qpqual,
5211 Index scanrelid,
5212 Oid indexid,
5213 List *indexqual,
5214 List *indexorderby,
5215 List *indextlist,
5216 ScanDirection indexscandir)
5217 {
5218 IndexOnlyScan *node = makeNode(IndexOnlyScan);
5219 Plan *plan = &node->scan.plan;
5220
5221 plan->targetlist = qptlist;
5222 plan->qual = qpqual;
5223 plan->lefttree = NULL;
5224 plan->righttree = NULL;
5225 node->scan.scanrelid = scanrelid;
5226 node->indexid = indexid;
5227 node->indexqual = indexqual;
5228 node->indexorderby = indexorderby;
5229 node->indextlist = indextlist;
5230 node->indexorderdir = indexscandir;
5231
5232 return node;
5233 }
5234
5235 static BitmapIndexScan *
make_bitmap_indexscan(Index scanrelid,Oid indexid,List * indexqual,List * indexqualorig)5236 make_bitmap_indexscan(Index scanrelid,
5237 Oid indexid,
5238 List *indexqual,
5239 List *indexqualorig)
5240 {
5241 BitmapIndexScan *node = makeNode(BitmapIndexScan);
5242 Plan *plan = &node->scan.plan;
5243
5244 plan->targetlist = NIL; /* not used */
5245 plan->qual = NIL; /* not used */
5246 plan->lefttree = NULL;
5247 plan->righttree = NULL;
5248 node->scan.scanrelid = scanrelid;
5249 node->indexid = indexid;
5250 node->indexqual = indexqual;
5251 node->indexqualorig = indexqualorig;
5252
5253 return node;
5254 }
5255
5256 static BitmapHeapScan *
make_bitmap_heapscan(List * qptlist,List * qpqual,Plan * lefttree,List * bitmapqualorig,Index scanrelid)5257 make_bitmap_heapscan(List *qptlist,
5258 List *qpqual,
5259 Plan *lefttree,
5260 List *bitmapqualorig,
5261 Index scanrelid)
5262 {
5263 BitmapHeapScan *node = makeNode(BitmapHeapScan);
5264 Plan *plan = &node->scan.plan;
5265
5266 plan->targetlist = qptlist;
5267 plan->qual = qpqual;
5268 plan->lefttree = lefttree;
5269 plan->righttree = NULL;
5270 node->scan.scanrelid = scanrelid;
5271 node->bitmapqualorig = bitmapqualorig;
5272
5273 return node;
5274 }
5275
5276 static TidScan *
make_tidscan(List * qptlist,List * qpqual,Index scanrelid,List * tidquals)5277 make_tidscan(List *qptlist,
5278 List *qpqual,
5279 Index scanrelid,
5280 List *tidquals)
5281 {
5282 TidScan *node = makeNode(TidScan);
5283 Plan *plan = &node->scan.plan;
5284
5285 plan->targetlist = qptlist;
5286 plan->qual = qpqual;
5287 plan->lefttree = NULL;
5288 plan->righttree = NULL;
5289 node->scan.scanrelid = scanrelid;
5290 node->tidquals = tidquals;
5291
5292 return node;
5293 }
5294
5295 static SubqueryScan *
make_subqueryscan(List * qptlist,List * qpqual,Index scanrelid,Plan * subplan)5296 make_subqueryscan(List *qptlist,
5297 List *qpqual,
5298 Index scanrelid,
5299 Plan *subplan)
5300 {
5301 SubqueryScan *node = makeNode(SubqueryScan);
5302 Plan *plan = &node->scan.plan;
5303
5304 plan->targetlist = qptlist;
5305 plan->qual = qpqual;
5306 plan->lefttree = NULL;
5307 plan->righttree = NULL;
5308 node->scan.scanrelid = scanrelid;
5309 node->subplan = subplan;
5310
5311 return node;
5312 }
5313
5314 static FunctionScan *
make_functionscan(List * qptlist,List * qpqual,Index scanrelid,List * functions,bool funcordinality)5315 make_functionscan(List *qptlist,
5316 List *qpqual,
5317 Index scanrelid,
5318 List *functions,
5319 bool funcordinality)
5320 {
5321 FunctionScan *node = makeNode(FunctionScan);
5322 Plan *plan = &node->scan.plan;
5323
5324 plan->targetlist = qptlist;
5325 plan->qual = qpqual;
5326 plan->lefttree = NULL;
5327 plan->righttree = NULL;
5328 node->scan.scanrelid = scanrelid;
5329 node->functions = functions;
5330 node->funcordinality = funcordinality;
5331
5332 return node;
5333 }
5334
5335 static TableFuncScan *
make_tablefuncscan(List * qptlist,List * qpqual,Index scanrelid,TableFunc * tablefunc)5336 make_tablefuncscan(List *qptlist,
5337 List *qpqual,
5338 Index scanrelid,
5339 TableFunc *tablefunc)
5340 {
5341 TableFuncScan *node = makeNode(TableFuncScan);
5342 Plan *plan = &node->scan.plan;
5343
5344 plan->targetlist = qptlist;
5345 plan->qual = qpqual;
5346 plan->lefttree = NULL;
5347 plan->righttree = NULL;
5348 node->scan.scanrelid = scanrelid;
5349 node->tablefunc = tablefunc;
5350
5351 return node;
5352 }
5353
5354 static ValuesScan *
make_valuesscan(List * qptlist,List * qpqual,Index scanrelid,List * values_lists)5355 make_valuesscan(List *qptlist,
5356 List *qpqual,
5357 Index scanrelid,
5358 List *values_lists)
5359 {
5360 ValuesScan *node = makeNode(ValuesScan);
5361 Plan *plan = &node->scan.plan;
5362
5363 plan->targetlist = qptlist;
5364 plan->qual = qpqual;
5365 plan->lefttree = NULL;
5366 plan->righttree = NULL;
5367 node->scan.scanrelid = scanrelid;
5368 node->values_lists = values_lists;
5369
5370 return node;
5371 }
5372
5373 static CteScan *
make_ctescan(List * qptlist,List * qpqual,Index scanrelid,int ctePlanId,int cteParam)5374 make_ctescan(List *qptlist,
5375 List *qpqual,
5376 Index scanrelid,
5377 int ctePlanId,
5378 int cteParam)
5379 {
5380 CteScan *node = makeNode(CteScan);
5381 Plan *plan = &node->scan.plan;
5382
5383 plan->targetlist = qptlist;
5384 plan->qual = qpqual;
5385 plan->lefttree = NULL;
5386 plan->righttree = NULL;
5387 node->scan.scanrelid = scanrelid;
5388 node->ctePlanId = ctePlanId;
5389 node->cteParam = cteParam;
5390
5391 return node;
5392 }
5393
5394 static NamedTuplestoreScan *
make_namedtuplestorescan(List * qptlist,List * qpqual,Index scanrelid,char * enrname)5395 make_namedtuplestorescan(List *qptlist,
5396 List *qpqual,
5397 Index scanrelid,
5398 char *enrname)
5399 {
5400 NamedTuplestoreScan *node = makeNode(NamedTuplestoreScan);
5401 Plan *plan = &node->scan.plan;
5402
5403 /* cost should be inserted by caller */
5404 plan->targetlist = qptlist;
5405 plan->qual = qpqual;
5406 plan->lefttree = NULL;
5407 plan->righttree = NULL;
5408 node->scan.scanrelid = scanrelid;
5409 node->enrname = enrname;
5410
5411 return node;
5412 }
5413
5414 static WorkTableScan *
make_worktablescan(List * qptlist,List * qpqual,Index scanrelid,int wtParam)5415 make_worktablescan(List *qptlist,
5416 List *qpqual,
5417 Index scanrelid,
5418 int wtParam)
5419 {
5420 WorkTableScan *node = makeNode(WorkTableScan);
5421 Plan *plan = &node->scan.plan;
5422
5423 plan->targetlist = qptlist;
5424 plan->qual = qpqual;
5425 plan->lefttree = NULL;
5426 plan->righttree = NULL;
5427 node->scan.scanrelid = scanrelid;
5428 node->wtParam = wtParam;
5429
5430 return node;
5431 }
5432
5433 ForeignScan *
make_foreignscan(List * qptlist,List * qpqual,Index scanrelid,List * fdw_exprs,List * fdw_private,List * fdw_scan_tlist,List * fdw_recheck_quals,Plan * outer_plan)5434 make_foreignscan(List *qptlist,
5435 List *qpqual,
5436 Index scanrelid,
5437 List *fdw_exprs,
5438 List *fdw_private,
5439 List *fdw_scan_tlist,
5440 List *fdw_recheck_quals,
5441 Plan *outer_plan)
5442 {
5443 ForeignScan *node = makeNode(ForeignScan);
5444 Plan *plan = &node->scan.plan;
5445
5446 /* cost will be filled in by create_foreignscan_plan */
5447 plan->targetlist = qptlist;
5448 plan->qual = qpqual;
5449 plan->lefttree = outer_plan;
5450 plan->righttree = NULL;
5451 node->scan.scanrelid = scanrelid;
5452 node->operation = CMD_SELECT;
5453 /* fs_server will be filled in by create_foreignscan_plan */
5454 node->fs_server = InvalidOid;
5455 node->fdw_exprs = fdw_exprs;
5456 node->fdw_private = fdw_private;
5457 node->fdw_scan_tlist = fdw_scan_tlist;
5458 node->fdw_recheck_quals = fdw_recheck_quals;
5459 /* fs_relids will be filled in by create_foreignscan_plan */
5460 node->fs_relids = NULL;
5461 /* fsSystemCol will be filled in by create_foreignscan_plan */
5462 node->fsSystemCol = false;
5463
5464 return node;
5465 }
5466
5467 static RecursiveUnion *
make_recursive_union(List * tlist,Plan * lefttree,Plan * righttree,int wtParam,List * distinctList,long numGroups)5468 make_recursive_union(List *tlist,
5469 Plan *lefttree,
5470 Plan *righttree,
5471 int wtParam,
5472 List *distinctList,
5473 long numGroups)
5474 {
5475 RecursiveUnion *node = makeNode(RecursiveUnion);
5476 Plan *plan = &node->plan;
5477 int numCols = list_length(distinctList);
5478
5479 plan->targetlist = tlist;
5480 plan->qual = NIL;
5481 plan->lefttree = lefttree;
5482 plan->righttree = righttree;
5483 node->wtParam = wtParam;
5484
5485 /*
5486 * convert SortGroupClause list into arrays of attr indexes and equality
5487 * operators, as wanted by executor
5488 */
5489 node->numCols = numCols;
5490 if (numCols > 0)
5491 {
5492 int keyno = 0;
5493 AttrNumber *dupColIdx;
5494 Oid *dupOperators;
5495 Oid *dupCollations;
5496 ListCell *slitem;
5497
5498 dupColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
5499 dupOperators = (Oid *) palloc(sizeof(Oid) * numCols);
5500 dupCollations = (Oid *) palloc(sizeof(Oid) * numCols);
5501
5502 foreach(slitem, distinctList)
5503 {
5504 SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
5505 TargetEntry *tle = get_sortgroupclause_tle(sortcl,
5506 plan->targetlist);
5507
5508 dupColIdx[keyno] = tle->resno;
5509 dupOperators[keyno] = sortcl->eqop;
5510 dupCollations[keyno] = exprCollation((Node *) tle->expr);
5511 Assert(OidIsValid(dupOperators[keyno]));
5512 keyno++;
5513 }
5514 node->dupColIdx = dupColIdx;
5515 node->dupOperators = dupOperators;
5516 node->dupCollations = dupCollations;
5517 }
5518 node->numGroups = numGroups;
5519
5520 return node;
5521 }
5522
5523 static BitmapAnd *
make_bitmap_and(List * bitmapplans)5524 make_bitmap_and(List *bitmapplans)
5525 {
5526 BitmapAnd *node = makeNode(BitmapAnd);
5527 Plan *plan = &node->plan;
5528
5529 plan->targetlist = NIL;
5530 plan->qual = NIL;
5531 plan->lefttree = NULL;
5532 plan->righttree = NULL;
5533 node->bitmapplans = bitmapplans;
5534
5535 return node;
5536 }
5537
5538 static BitmapOr *
make_bitmap_or(List * bitmapplans)5539 make_bitmap_or(List *bitmapplans)
5540 {
5541 BitmapOr *node = makeNode(BitmapOr);
5542 Plan *plan = &node->plan;
5543
5544 plan->targetlist = NIL;
5545 plan->qual = NIL;
5546 plan->lefttree = NULL;
5547 plan->righttree = NULL;
5548 node->bitmapplans = bitmapplans;
5549
5550 return node;
5551 }
5552
5553 static NestLoop *
make_nestloop(List * tlist,List * joinclauses,List * otherclauses,List * nestParams,Plan * lefttree,Plan * righttree,JoinType jointype,bool inner_unique)5554 make_nestloop(List *tlist,
5555 List *joinclauses,
5556 List *otherclauses,
5557 List *nestParams,
5558 Plan *lefttree,
5559 Plan *righttree,
5560 JoinType jointype,
5561 bool inner_unique)
5562 {
5563 NestLoop *node = makeNode(NestLoop);
5564 Plan *plan = &node->join.plan;
5565
5566 plan->targetlist = tlist;
5567 plan->qual = otherclauses;
5568 plan->lefttree = lefttree;
5569 plan->righttree = righttree;
5570 node->join.jointype = jointype;
5571 node->join.inner_unique = inner_unique;
5572 node->join.joinqual = joinclauses;
5573 node->nestParams = nestParams;
5574
5575 return node;
5576 }
5577
5578 static HashJoin *
make_hashjoin(List * tlist,List * joinclauses,List * otherclauses,List * hashclauses,List * hashoperators,List * hashcollations,List * hashkeys,Plan * lefttree,Plan * righttree,JoinType jointype,bool inner_unique)5579 make_hashjoin(List *tlist,
5580 List *joinclauses,
5581 List *otherclauses,
5582 List *hashclauses,
5583 List *hashoperators,
5584 List *hashcollations,
5585 List *hashkeys,
5586 Plan *lefttree,
5587 Plan *righttree,
5588 JoinType jointype,
5589 bool inner_unique)
5590 {
5591 HashJoin *node = makeNode(HashJoin);
5592 Plan *plan = &node->join.plan;
5593
5594 plan->targetlist = tlist;
5595 plan->qual = otherclauses;
5596 plan->lefttree = lefttree;
5597 plan->righttree = righttree;
5598 node->hashclauses = hashclauses;
5599 node->hashoperators = hashoperators;
5600 node->hashcollations = hashcollations;
5601 node->hashkeys = hashkeys;
5602 node->join.jointype = jointype;
5603 node->join.inner_unique = inner_unique;
5604 node->join.joinqual = joinclauses;
5605
5606 return node;
5607 }
5608
5609 static Hash *
make_hash(Plan * lefttree,List * hashkeys,Oid skewTable,AttrNumber skewColumn,bool skewInherit)5610 make_hash(Plan *lefttree,
5611 List *hashkeys,
5612 Oid skewTable,
5613 AttrNumber skewColumn,
5614 bool skewInherit)
5615 {
5616 Hash *node = makeNode(Hash);
5617 Plan *plan = &node->plan;
5618
5619 plan->targetlist = lefttree->targetlist;
5620 plan->qual = NIL;
5621 plan->lefttree = lefttree;
5622 plan->righttree = NULL;
5623
5624 node->hashkeys = hashkeys;
5625 node->skewTable = skewTable;
5626 node->skewColumn = skewColumn;
5627 node->skewInherit = skewInherit;
5628
5629 return node;
5630 }
5631
5632 static MergeJoin *
make_mergejoin(List * tlist,List * joinclauses,List * otherclauses,List * mergeclauses,Oid * mergefamilies,Oid * mergecollations,int * mergestrategies,bool * mergenullsfirst,Plan * lefttree,Plan * righttree,JoinType jointype,bool inner_unique,bool skip_mark_restore)5633 make_mergejoin(List *tlist,
5634 List *joinclauses,
5635 List *otherclauses,
5636 List *mergeclauses,
5637 Oid *mergefamilies,
5638 Oid *mergecollations,
5639 int *mergestrategies,
5640 bool *mergenullsfirst,
5641 Plan *lefttree,
5642 Plan *righttree,
5643 JoinType jointype,
5644 bool inner_unique,
5645 bool skip_mark_restore)
5646 {
5647 MergeJoin *node = makeNode(MergeJoin);
5648 Plan *plan = &node->join.plan;
5649
5650 plan->targetlist = tlist;
5651 plan->qual = otherclauses;
5652 plan->lefttree = lefttree;
5653 plan->righttree = righttree;
5654 node->skip_mark_restore = skip_mark_restore;
5655 node->mergeclauses = mergeclauses;
5656 node->mergeFamilies = mergefamilies;
5657 node->mergeCollations = mergecollations;
5658 node->mergeStrategies = mergestrategies;
5659 node->mergeNullsFirst = mergenullsfirst;
5660 node->join.jointype = jointype;
5661 node->join.inner_unique = inner_unique;
5662 node->join.joinqual = joinclauses;
5663
5664 return node;
5665 }
5666
5667 /*
5668 * make_sort --- basic routine to build a Sort plan node
5669 *
5670 * Caller must have built the sortColIdx, sortOperators, collations, and
5671 * nullsFirst arrays already.
5672 */
5673 static Sort *
make_sort(Plan * lefttree,int numCols,AttrNumber * sortColIdx,Oid * sortOperators,Oid * collations,bool * nullsFirst)5674 make_sort(Plan *lefttree, int numCols,
5675 AttrNumber *sortColIdx, Oid *sortOperators,
5676 Oid *collations, bool *nullsFirst)
5677 {
5678 Sort *node = makeNode(Sort);
5679 Plan *plan = &node->plan;
5680
5681 plan->targetlist = lefttree->targetlist;
5682 plan->qual = NIL;
5683 plan->lefttree = lefttree;
5684 plan->righttree = NULL;
5685 node->numCols = numCols;
5686 node->sortColIdx = sortColIdx;
5687 node->sortOperators = sortOperators;
5688 node->collations = collations;
5689 node->nullsFirst = nullsFirst;
5690
5691 return node;
5692 }
5693
5694 /*
5695 * prepare_sort_from_pathkeys
5696 * Prepare to sort according to given pathkeys
5697 *
5698 * This is used to set up for Sort, MergeAppend, and Gather Merge nodes. It
5699 * calculates the executor's representation of the sort key information, and
5700 * adjusts the plan targetlist if needed to add resjunk sort columns.
5701 *
5702 * Input parameters:
5703 * 'lefttree' is the plan node which yields input tuples
5704 * 'pathkeys' is the list of pathkeys by which the result is to be sorted
5705 * 'relids' identifies the child relation being sorted, if any
5706 * 'reqColIdx' is NULL or an array of required sort key column numbers
5707 * 'adjust_tlist_in_place' is true if lefttree must be modified in-place
5708 *
5709 * We must convert the pathkey information into arrays of sort key column
5710 * numbers, sort operator OIDs, collation OIDs, and nulls-first flags,
5711 * which is the representation the executor wants. These are returned into
5712 * the output parameters *p_numsortkeys etc.
5713 *
5714 * When looking for matches to an EquivalenceClass's members, we will only
5715 * consider child EC members if they belong to given 'relids'. This protects
5716 * against possible incorrect matches to child expressions that contain no
5717 * Vars.
5718 *
5719 * If reqColIdx isn't NULL then it contains sort key column numbers that
5720 * we should match. This is used when making child plans for a MergeAppend;
5721 * it's an error if we can't match the columns.
5722 *
5723 * If the pathkeys include expressions that aren't simple Vars, we will
5724 * usually need to add resjunk items to the input plan's targetlist to
5725 * compute these expressions, since a Sort or MergeAppend node itself won't
5726 * do any such calculations. If the input plan type isn't one that can do
5727 * projections, this means adding a Result node just to do the projection.
5728 * However, the caller can pass adjust_tlist_in_place = true to force the
5729 * lefttree tlist to be modified in-place regardless of whether the node type
5730 * can project --- we use this for fixing the tlist of MergeAppend itself.
5731 *
5732 * Returns the node which is to be the input to the Sort (either lefttree,
5733 * or a Result stacked atop lefttree).
5734 */
5735 static Plan *
prepare_sort_from_pathkeys(Plan * lefttree,List * pathkeys,Relids relids,const AttrNumber * reqColIdx,bool adjust_tlist_in_place,int * p_numsortkeys,AttrNumber ** p_sortColIdx,Oid ** p_sortOperators,Oid ** p_collations,bool ** p_nullsFirst)5736 prepare_sort_from_pathkeys(Plan *lefttree, List *pathkeys,
5737 Relids relids,
5738 const AttrNumber *reqColIdx,
5739 bool adjust_tlist_in_place,
5740 int *p_numsortkeys,
5741 AttrNumber **p_sortColIdx,
5742 Oid **p_sortOperators,
5743 Oid **p_collations,
5744 bool **p_nullsFirst)
5745 {
5746 List *tlist = lefttree->targetlist;
5747 ListCell *i;
5748 int numsortkeys;
5749 AttrNumber *sortColIdx;
5750 Oid *sortOperators;
5751 Oid *collations;
5752 bool *nullsFirst;
5753
5754 /*
5755 * We will need at most list_length(pathkeys) sort columns; possibly less
5756 */
5757 numsortkeys = list_length(pathkeys);
5758 sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
5759 sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
5760 collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
5761 nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
5762
5763 numsortkeys = 0;
5764
5765 foreach(i, pathkeys)
5766 {
5767 PathKey *pathkey = (PathKey *) lfirst(i);
5768 EquivalenceClass *ec = pathkey->pk_eclass;
5769 EquivalenceMember *em;
5770 TargetEntry *tle = NULL;
5771 Oid pk_datatype = InvalidOid;
5772 Oid sortop;
5773 ListCell *j;
5774
5775 if (ec->ec_has_volatile)
5776 {
5777 /*
5778 * If the pathkey's EquivalenceClass is volatile, then it must
5779 * have come from an ORDER BY clause, and we have to match it to
5780 * that same targetlist entry.
5781 */
5782 if (ec->ec_sortref == 0) /* can't happen */
5783 elog(ERROR, "volatile EquivalenceClass has no sortref");
5784 tle = get_sortgroupref_tle(ec->ec_sortref, tlist);
5785 Assert(tle);
5786 Assert(list_length(ec->ec_members) == 1);
5787 pk_datatype = ((EquivalenceMember *) linitial(ec->ec_members))->em_datatype;
5788 }
5789 else if (reqColIdx != NULL)
5790 {
5791 /*
5792 * If we are given a sort column number to match, only consider
5793 * the single TLE at that position. It's possible that there is
5794 * no such TLE, in which case fall through and generate a resjunk
5795 * targetentry (we assume this must have happened in the parent
5796 * plan as well). If there is a TLE but it doesn't match the
5797 * pathkey's EC, we do the same, which is probably the wrong thing
5798 * but we'll leave it to caller to complain about the mismatch.
5799 */
5800 tle = get_tle_by_resno(tlist, reqColIdx[numsortkeys]);
5801 if (tle)
5802 {
5803 em = find_ec_member_for_tle(ec, tle, relids);
5804 if (em)
5805 {
5806 /* found expr at right place in tlist */
5807 pk_datatype = em->em_datatype;
5808 }
5809 else
5810 tle = NULL;
5811 }
5812 }
5813 else
5814 {
5815 /*
5816 * Otherwise, we can sort by any non-constant expression listed in
5817 * the pathkey's EquivalenceClass. For now, we take the first
5818 * tlist item found in the EC. If there's no match, we'll generate
5819 * a resjunk entry using the first EC member that is an expression
5820 * in the input's vars. (The non-const restriction only matters
5821 * if the EC is below_outer_join; but if it isn't, it won't
5822 * contain consts anyway, else we'd have discarded the pathkey as
5823 * redundant.)
5824 *
5825 * XXX if we have a choice, is there any way of figuring out which
5826 * might be cheapest to execute? (For example, int4lt is likely
5827 * much cheaper to execute than numericlt, but both might appear
5828 * in the same equivalence class...) Not clear that we ever will
5829 * have an interesting choice in practice, so it may not matter.
5830 */
5831 foreach(j, tlist)
5832 {
5833 tle = (TargetEntry *) lfirst(j);
5834 em = find_ec_member_for_tle(ec, tle, relids);
5835 if (em)
5836 {
5837 /* found expr already in tlist */
5838 pk_datatype = em->em_datatype;
5839 break;
5840 }
5841 tle = NULL;
5842 }
5843 }
5844
5845 if (!tle)
5846 {
5847 /*
5848 * No matching tlist item; look for a computable expression. Note
5849 * that we treat Aggrefs as if they were variables; this is
5850 * necessary when attempting to sort the output from an Agg node
5851 * for use in a WindowFunc (since grouping_planner will have
5852 * treated the Aggrefs as variables, too). Likewise, if we find a
5853 * WindowFunc in a sort expression, treat it as a variable.
5854 */
5855 Expr *sortexpr = NULL;
5856
5857 foreach(j, ec->ec_members)
5858 {
5859 EquivalenceMember *em = (EquivalenceMember *) lfirst(j);
5860 List *exprvars;
5861 ListCell *k;
5862
5863 /*
5864 * We shouldn't be trying to sort by an equivalence class that
5865 * contains a constant, so no need to consider such cases any
5866 * further.
5867 */
5868 if (em->em_is_const)
5869 continue;
5870
5871 /*
5872 * Ignore child members unless they belong to the rel being
5873 * sorted.
5874 */
5875 if (em->em_is_child &&
5876 !bms_is_subset(em->em_relids, relids))
5877 continue;
5878
5879 sortexpr = em->em_expr;
5880 exprvars = pull_var_clause((Node *) sortexpr,
5881 PVC_INCLUDE_AGGREGATES |
5882 PVC_INCLUDE_WINDOWFUNCS |
5883 PVC_INCLUDE_PLACEHOLDERS);
5884 foreach(k, exprvars)
5885 {
5886 if (!tlist_member_ignore_relabel(lfirst(k), tlist))
5887 break;
5888 }
5889 list_free(exprvars);
5890 if (!k)
5891 {
5892 pk_datatype = em->em_datatype;
5893 break; /* found usable expression */
5894 }
5895 }
5896 if (!j)
5897 elog(ERROR, "could not find pathkey item to sort");
5898
5899 /*
5900 * Do we need to insert a Result node?
5901 */
5902 if (!adjust_tlist_in_place &&
5903 !is_projection_capable_plan(lefttree))
5904 {
5905 /* copy needed so we don't modify input's tlist below */
5906 tlist = copyObject(tlist);
5907 lefttree = inject_projection_plan(lefttree, tlist,
5908 lefttree->parallel_safe);
5909 }
5910
5911 /* Don't bother testing is_projection_capable_plan again */
5912 adjust_tlist_in_place = true;
5913
5914 /*
5915 * Add resjunk entry to input's tlist
5916 */
5917 tle = makeTargetEntry(sortexpr,
5918 list_length(tlist) + 1,
5919 NULL,
5920 true);
5921 tlist = lappend(tlist, tle);
5922 lefttree->targetlist = tlist; /* just in case NIL before */
5923 }
5924
5925 /*
5926 * Look up the correct sort operator from the PathKey's slightly
5927 * abstracted representation.
5928 */
5929 sortop = get_opfamily_member(pathkey->pk_opfamily,
5930 pk_datatype,
5931 pk_datatype,
5932 pathkey->pk_strategy);
5933 if (!OidIsValid(sortop)) /* should not happen */
5934 elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
5935 pathkey->pk_strategy, pk_datatype, pk_datatype,
5936 pathkey->pk_opfamily);
5937
5938 /* Add the column to the sort arrays */
5939 sortColIdx[numsortkeys] = tle->resno;
5940 sortOperators[numsortkeys] = sortop;
5941 collations[numsortkeys] = ec->ec_collation;
5942 nullsFirst[numsortkeys] = pathkey->pk_nulls_first;
5943 numsortkeys++;
5944 }
5945
5946 /* Return results */
5947 *p_numsortkeys = numsortkeys;
5948 *p_sortColIdx = sortColIdx;
5949 *p_sortOperators = sortOperators;
5950 *p_collations = collations;
5951 *p_nullsFirst = nullsFirst;
5952
5953 return lefttree;
5954 }
5955
5956 /*
5957 * find_ec_member_for_tle
5958 * Locate an EquivalenceClass member matching the given TLE, if any
5959 *
5960 * Child EC members are ignored unless they belong to given 'relids'.
5961 */
5962 static EquivalenceMember *
find_ec_member_for_tle(EquivalenceClass * ec,TargetEntry * tle,Relids relids)5963 find_ec_member_for_tle(EquivalenceClass *ec,
5964 TargetEntry *tle,
5965 Relids relids)
5966 {
5967 Expr *tlexpr;
5968 ListCell *lc;
5969
5970 /* We ignore binary-compatible relabeling on both ends */
5971 tlexpr = tle->expr;
5972 while (tlexpr && IsA(tlexpr, RelabelType))
5973 tlexpr = ((RelabelType *) tlexpr)->arg;
5974
5975 foreach(lc, ec->ec_members)
5976 {
5977 EquivalenceMember *em = (EquivalenceMember *) lfirst(lc);
5978 Expr *emexpr;
5979
5980 /*
5981 * We shouldn't be trying to sort by an equivalence class that
5982 * contains a constant, so no need to consider such cases any further.
5983 */
5984 if (em->em_is_const)
5985 continue;
5986
5987 /*
5988 * Ignore child members unless they belong to the rel being sorted.
5989 */
5990 if (em->em_is_child &&
5991 !bms_is_subset(em->em_relids, relids))
5992 continue;
5993
5994 /* Match if same expression (after stripping relabel) */
5995 emexpr = em->em_expr;
5996 while (emexpr && IsA(emexpr, RelabelType))
5997 emexpr = ((RelabelType *) emexpr)->arg;
5998
5999 if (equal(emexpr, tlexpr))
6000 return em;
6001 }
6002
6003 return NULL;
6004 }
6005
6006 /*
6007 * make_sort_from_pathkeys
6008 * Create sort plan to sort according to given pathkeys
6009 *
6010 * 'lefttree' is the node which yields input tuples
6011 * 'pathkeys' is the list of pathkeys by which the result is to be sorted
6012 * 'relids' is the set of relations required by prepare_sort_from_pathkeys()
6013 */
6014 static Sort *
make_sort_from_pathkeys(Plan * lefttree,List * pathkeys,Relids relids)6015 make_sort_from_pathkeys(Plan *lefttree, List *pathkeys, Relids relids)
6016 {
6017 int numsortkeys;
6018 AttrNumber *sortColIdx;
6019 Oid *sortOperators;
6020 Oid *collations;
6021 bool *nullsFirst;
6022
6023 /* Compute sort column info, and adjust lefttree as needed */
6024 lefttree = prepare_sort_from_pathkeys(lefttree, pathkeys,
6025 relids,
6026 NULL,
6027 false,
6028 &numsortkeys,
6029 &sortColIdx,
6030 &sortOperators,
6031 &collations,
6032 &nullsFirst);
6033
6034 /* Now build the Sort node */
6035 return make_sort(lefttree, numsortkeys,
6036 sortColIdx, sortOperators,
6037 collations, nullsFirst);
6038 }
6039
6040 /*
6041 * make_sort_from_sortclauses
6042 * Create sort plan to sort according to given sortclauses
6043 *
6044 * 'sortcls' is a list of SortGroupClauses
6045 * 'lefttree' is the node which yields input tuples
6046 */
6047 Sort *
make_sort_from_sortclauses(List * sortcls,Plan * lefttree)6048 make_sort_from_sortclauses(List *sortcls, Plan *lefttree)
6049 {
6050 List *sub_tlist = lefttree->targetlist;
6051 ListCell *l;
6052 int numsortkeys;
6053 AttrNumber *sortColIdx;
6054 Oid *sortOperators;
6055 Oid *collations;
6056 bool *nullsFirst;
6057
6058 /* Convert list-ish representation to arrays wanted by executor */
6059 numsortkeys = list_length(sortcls);
6060 sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
6061 sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
6062 collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
6063 nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
6064
6065 numsortkeys = 0;
6066 foreach(l, sortcls)
6067 {
6068 SortGroupClause *sortcl = (SortGroupClause *) lfirst(l);
6069 TargetEntry *tle = get_sortgroupclause_tle(sortcl, sub_tlist);
6070
6071 sortColIdx[numsortkeys] = tle->resno;
6072 sortOperators[numsortkeys] = sortcl->sortop;
6073 collations[numsortkeys] = exprCollation((Node *) tle->expr);
6074 nullsFirst[numsortkeys] = sortcl->nulls_first;
6075 numsortkeys++;
6076 }
6077
6078 return make_sort(lefttree, numsortkeys,
6079 sortColIdx, sortOperators,
6080 collations, nullsFirst);
6081 }
6082
6083 /*
6084 * make_sort_from_groupcols
6085 * Create sort plan to sort based on grouping columns
6086 *
6087 * 'groupcls' is the list of SortGroupClauses
6088 * 'grpColIdx' gives the column numbers to use
6089 *
6090 * This might look like it could be merged with make_sort_from_sortclauses,
6091 * but presently we *must* use the grpColIdx[] array to locate sort columns,
6092 * because the child plan's tlist is not marked with ressortgroupref info
6093 * appropriate to the grouping node. So, only the sort ordering info
6094 * is used from the SortGroupClause entries.
6095 */
6096 static Sort *
make_sort_from_groupcols(List * groupcls,AttrNumber * grpColIdx,Plan * lefttree)6097 make_sort_from_groupcols(List *groupcls,
6098 AttrNumber *grpColIdx,
6099 Plan *lefttree)
6100 {
6101 List *sub_tlist = lefttree->targetlist;
6102 ListCell *l;
6103 int numsortkeys;
6104 AttrNumber *sortColIdx;
6105 Oid *sortOperators;
6106 Oid *collations;
6107 bool *nullsFirst;
6108
6109 /* Convert list-ish representation to arrays wanted by executor */
6110 numsortkeys = list_length(groupcls);
6111 sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
6112 sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
6113 collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
6114 nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
6115
6116 numsortkeys = 0;
6117 foreach(l, groupcls)
6118 {
6119 SortGroupClause *grpcl = (SortGroupClause *) lfirst(l);
6120 TargetEntry *tle = get_tle_by_resno(sub_tlist, grpColIdx[numsortkeys]);
6121
6122 if (!tle)
6123 elog(ERROR, "could not retrieve tle for sort-from-groupcols");
6124
6125 sortColIdx[numsortkeys] = tle->resno;
6126 sortOperators[numsortkeys] = grpcl->sortop;
6127 collations[numsortkeys] = exprCollation((Node *) tle->expr);
6128 nullsFirst[numsortkeys] = grpcl->nulls_first;
6129 numsortkeys++;
6130 }
6131
6132 return make_sort(lefttree, numsortkeys,
6133 sortColIdx, sortOperators,
6134 collations, nullsFirst);
6135 }
6136
6137 static Material *
make_material(Plan * lefttree)6138 make_material(Plan *lefttree)
6139 {
6140 Material *node = makeNode(Material);
6141 Plan *plan = &node->plan;
6142
6143 plan->targetlist = lefttree->targetlist;
6144 plan->qual = NIL;
6145 plan->lefttree = lefttree;
6146 plan->righttree = NULL;
6147
6148 return node;
6149 }
6150
6151 /*
6152 * materialize_finished_plan: stick a Material node atop a completed plan
6153 *
6154 * There are a couple of places where we want to attach a Material node
6155 * after completion of create_plan(), without any MaterialPath path.
6156 * Those places should probably be refactored someday to do this on the
6157 * Path representation, but it's not worth the trouble yet.
6158 */
6159 Plan *
materialize_finished_plan(Plan * subplan)6160 materialize_finished_plan(Plan *subplan)
6161 {
6162 Plan *matplan;
6163 Path matpath; /* dummy for result of cost_material */
6164
6165 matplan = (Plan *) make_material(subplan);
6166
6167 /*
6168 * XXX horrid kluge: if there are any initPlans attached to the subplan,
6169 * move them up to the Material node, which is now effectively the top
6170 * plan node in its query level. This prevents failure in
6171 * SS_finalize_plan(), which see for comments. We don't bother adjusting
6172 * the subplan's cost estimate for this.
6173 */
6174 matplan->initPlan = subplan->initPlan;
6175 subplan->initPlan = NIL;
6176
6177 /* Set cost data */
6178 cost_material(&matpath,
6179 subplan->startup_cost,
6180 subplan->total_cost,
6181 subplan->plan_rows,
6182 subplan->plan_width);
6183 matplan->startup_cost = matpath.startup_cost;
6184 matplan->total_cost = matpath.total_cost;
6185 matplan->plan_rows = subplan->plan_rows;
6186 matplan->plan_width = subplan->plan_width;
6187 matplan->parallel_aware = false;
6188 matplan->parallel_safe = subplan->parallel_safe;
6189
6190 return matplan;
6191 }
6192
6193 Agg *
make_agg(List * tlist,List * qual,AggStrategy aggstrategy,AggSplit aggsplit,int numGroupCols,AttrNumber * grpColIdx,Oid * grpOperators,Oid * grpCollations,List * groupingSets,List * chain,double dNumGroups,Plan * lefttree)6194 make_agg(List *tlist, List *qual,
6195 AggStrategy aggstrategy, AggSplit aggsplit,
6196 int numGroupCols, AttrNumber *grpColIdx, Oid *grpOperators, Oid *grpCollations,
6197 List *groupingSets, List *chain,
6198 double dNumGroups, Plan *lefttree)
6199 {
6200 Agg *node = makeNode(Agg);
6201 Plan *plan = &node->plan;
6202 long numGroups;
6203
6204 /* Reduce to long, but 'ware overflow! */
6205 numGroups = (long) Min(dNumGroups, (double) LONG_MAX);
6206
6207 node->aggstrategy = aggstrategy;
6208 node->aggsplit = aggsplit;
6209 node->numCols = numGroupCols;
6210 node->grpColIdx = grpColIdx;
6211 node->grpOperators = grpOperators;
6212 node->grpCollations = grpCollations;
6213 node->numGroups = numGroups;
6214 node->aggParams = NULL; /* SS_finalize_plan() will fill this */
6215 node->groupingSets = groupingSets;
6216 node->chain = chain;
6217
6218 plan->qual = qual;
6219 plan->targetlist = tlist;
6220 plan->lefttree = lefttree;
6221 plan->righttree = NULL;
6222
6223 return node;
6224 }
6225
6226 static WindowAgg *
make_windowagg(List * tlist,Index winref,int partNumCols,AttrNumber * partColIdx,Oid * partOperators,Oid * partCollations,int ordNumCols,AttrNumber * ordColIdx,Oid * ordOperators,Oid * ordCollations,int frameOptions,Node * startOffset,Node * endOffset,Oid startInRangeFunc,Oid endInRangeFunc,Oid inRangeColl,bool inRangeAsc,bool inRangeNullsFirst,Plan * lefttree)6227 make_windowagg(List *tlist, Index winref,
6228 int partNumCols, AttrNumber *partColIdx, Oid *partOperators, Oid *partCollations,
6229 int ordNumCols, AttrNumber *ordColIdx, Oid *ordOperators, Oid *ordCollations,
6230 int frameOptions, Node *startOffset, Node *endOffset,
6231 Oid startInRangeFunc, Oid endInRangeFunc,
6232 Oid inRangeColl, bool inRangeAsc, bool inRangeNullsFirst,
6233 Plan *lefttree)
6234 {
6235 WindowAgg *node = makeNode(WindowAgg);
6236 Plan *plan = &node->plan;
6237
6238 node->winref = winref;
6239 node->partNumCols = partNumCols;
6240 node->partColIdx = partColIdx;
6241 node->partOperators = partOperators;
6242 node->partCollations = partCollations;
6243 node->ordNumCols = ordNumCols;
6244 node->ordColIdx = ordColIdx;
6245 node->ordOperators = ordOperators;
6246 node->ordCollations = ordCollations;
6247 node->frameOptions = frameOptions;
6248 node->startOffset = startOffset;
6249 node->endOffset = endOffset;
6250 node->startInRangeFunc = startInRangeFunc;
6251 node->endInRangeFunc = endInRangeFunc;
6252 node->inRangeColl = inRangeColl;
6253 node->inRangeAsc = inRangeAsc;
6254 node->inRangeNullsFirst = inRangeNullsFirst;
6255
6256 plan->targetlist = tlist;
6257 plan->lefttree = lefttree;
6258 plan->righttree = NULL;
6259 /* WindowAgg nodes never have a qual clause */
6260 plan->qual = NIL;
6261
6262 return node;
6263 }
6264
6265 static Group *
make_group(List * tlist,List * qual,int numGroupCols,AttrNumber * grpColIdx,Oid * grpOperators,Oid * grpCollations,Plan * lefttree)6266 make_group(List *tlist,
6267 List *qual,
6268 int numGroupCols,
6269 AttrNumber *grpColIdx,
6270 Oid *grpOperators,
6271 Oid *grpCollations,
6272 Plan *lefttree)
6273 {
6274 Group *node = makeNode(Group);
6275 Plan *plan = &node->plan;
6276
6277 node->numCols = numGroupCols;
6278 node->grpColIdx = grpColIdx;
6279 node->grpOperators = grpOperators;
6280 node->grpCollations = grpCollations;
6281
6282 plan->qual = qual;
6283 plan->targetlist = tlist;
6284 plan->lefttree = lefttree;
6285 plan->righttree = NULL;
6286
6287 return node;
6288 }
6289
6290 /*
6291 * distinctList is a list of SortGroupClauses, identifying the targetlist items
6292 * that should be considered by the Unique filter. The input path must
6293 * already be sorted accordingly.
6294 */
6295 static Unique *
make_unique_from_sortclauses(Plan * lefttree,List * distinctList)6296 make_unique_from_sortclauses(Plan *lefttree, List *distinctList)
6297 {
6298 Unique *node = makeNode(Unique);
6299 Plan *plan = &node->plan;
6300 int numCols = list_length(distinctList);
6301 int keyno = 0;
6302 AttrNumber *uniqColIdx;
6303 Oid *uniqOperators;
6304 Oid *uniqCollations;
6305 ListCell *slitem;
6306
6307 plan->targetlist = lefttree->targetlist;
6308 plan->qual = NIL;
6309 plan->lefttree = lefttree;
6310 plan->righttree = NULL;
6311
6312 /*
6313 * convert SortGroupClause list into arrays of attr indexes and equality
6314 * operators, as wanted by executor
6315 */
6316 Assert(numCols > 0);
6317 uniqColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
6318 uniqOperators = (Oid *) palloc(sizeof(Oid) * numCols);
6319 uniqCollations = (Oid *) palloc(sizeof(Oid) * numCols);
6320
6321 foreach(slitem, distinctList)
6322 {
6323 SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
6324 TargetEntry *tle = get_sortgroupclause_tle(sortcl, plan->targetlist);
6325
6326 uniqColIdx[keyno] = tle->resno;
6327 uniqOperators[keyno] = sortcl->eqop;
6328 uniqCollations[keyno] = exprCollation((Node *) tle->expr);
6329 Assert(OidIsValid(uniqOperators[keyno]));
6330 keyno++;
6331 }
6332
6333 node->numCols = numCols;
6334 node->uniqColIdx = uniqColIdx;
6335 node->uniqOperators = uniqOperators;
6336 node->uniqCollations = uniqCollations;
6337
6338 return node;
6339 }
6340
6341 /*
6342 * as above, but use pathkeys to identify the sort columns and semantics
6343 */
6344 static Unique *
make_unique_from_pathkeys(Plan * lefttree,List * pathkeys,int numCols)6345 make_unique_from_pathkeys(Plan *lefttree, List *pathkeys, int numCols)
6346 {
6347 Unique *node = makeNode(Unique);
6348 Plan *plan = &node->plan;
6349 int keyno = 0;
6350 AttrNumber *uniqColIdx;
6351 Oid *uniqOperators;
6352 Oid *uniqCollations;
6353 ListCell *lc;
6354
6355 plan->targetlist = lefttree->targetlist;
6356 plan->qual = NIL;
6357 plan->lefttree = lefttree;
6358 plan->righttree = NULL;
6359
6360 /*
6361 * Convert pathkeys list into arrays of attr indexes and equality
6362 * operators, as wanted by executor. This has a lot in common with
6363 * prepare_sort_from_pathkeys ... maybe unify sometime?
6364 */
6365 Assert(numCols >= 0 && numCols <= list_length(pathkeys));
6366 uniqColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
6367 uniqOperators = (Oid *) palloc(sizeof(Oid) * numCols);
6368 uniqCollations = (Oid *) palloc(sizeof(Oid) * numCols);
6369
6370 foreach(lc, pathkeys)
6371 {
6372 PathKey *pathkey = (PathKey *) lfirst(lc);
6373 EquivalenceClass *ec = pathkey->pk_eclass;
6374 EquivalenceMember *em;
6375 TargetEntry *tle = NULL;
6376 Oid pk_datatype = InvalidOid;
6377 Oid eqop;
6378 ListCell *j;
6379
6380 /* Ignore pathkeys beyond the specified number of columns */
6381 if (keyno >= numCols)
6382 break;
6383
6384 if (ec->ec_has_volatile)
6385 {
6386 /*
6387 * If the pathkey's EquivalenceClass is volatile, then it must
6388 * have come from an ORDER BY clause, and we have to match it to
6389 * that same targetlist entry.
6390 */
6391 if (ec->ec_sortref == 0) /* can't happen */
6392 elog(ERROR, "volatile EquivalenceClass has no sortref");
6393 tle = get_sortgroupref_tle(ec->ec_sortref, plan->targetlist);
6394 Assert(tle);
6395 Assert(list_length(ec->ec_members) == 1);
6396 pk_datatype = ((EquivalenceMember *) linitial(ec->ec_members))->em_datatype;
6397 }
6398 else
6399 {
6400 /*
6401 * Otherwise, we can use any non-constant expression listed in the
6402 * pathkey's EquivalenceClass. For now, we take the first tlist
6403 * item found in the EC.
6404 */
6405 foreach(j, plan->targetlist)
6406 {
6407 tle = (TargetEntry *) lfirst(j);
6408 em = find_ec_member_for_tle(ec, tle, NULL);
6409 if (em)
6410 {
6411 /* found expr already in tlist */
6412 pk_datatype = em->em_datatype;
6413 break;
6414 }
6415 tle = NULL;
6416 }
6417 }
6418
6419 if (!tle)
6420 elog(ERROR, "could not find pathkey item to sort");
6421
6422 /*
6423 * Look up the correct equality operator from the PathKey's slightly
6424 * abstracted representation.
6425 */
6426 eqop = get_opfamily_member(pathkey->pk_opfamily,
6427 pk_datatype,
6428 pk_datatype,
6429 BTEqualStrategyNumber);
6430 if (!OidIsValid(eqop)) /* should not happen */
6431 elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
6432 BTEqualStrategyNumber, pk_datatype, pk_datatype,
6433 pathkey->pk_opfamily);
6434
6435 uniqColIdx[keyno] = tle->resno;
6436 uniqOperators[keyno] = eqop;
6437 uniqCollations[keyno] = ec->ec_collation;
6438
6439 keyno++;
6440 }
6441
6442 node->numCols = numCols;
6443 node->uniqColIdx = uniqColIdx;
6444 node->uniqOperators = uniqOperators;
6445 node->uniqCollations = uniqCollations;
6446
6447 return node;
6448 }
6449
6450 static Gather *
make_gather(List * qptlist,List * qpqual,int nworkers,int rescan_param,bool single_copy,Plan * subplan)6451 make_gather(List *qptlist,
6452 List *qpqual,
6453 int nworkers,
6454 int rescan_param,
6455 bool single_copy,
6456 Plan *subplan)
6457 {
6458 Gather *node = makeNode(Gather);
6459 Plan *plan = &node->plan;
6460
6461 plan->targetlist = qptlist;
6462 plan->qual = qpqual;
6463 plan->lefttree = subplan;
6464 plan->righttree = NULL;
6465 node->num_workers = nworkers;
6466 node->rescan_param = rescan_param;
6467 node->single_copy = single_copy;
6468 node->invisible = false;
6469 node->initParam = NULL;
6470
6471 return node;
6472 }
6473
6474 /*
6475 * distinctList is a list of SortGroupClauses, identifying the targetlist
6476 * items that should be considered by the SetOp filter. The input path must
6477 * already be sorted accordingly.
6478 */
6479 static SetOp *
make_setop(SetOpCmd cmd,SetOpStrategy strategy,Plan * lefttree,List * distinctList,AttrNumber flagColIdx,int firstFlag,long numGroups)6480 make_setop(SetOpCmd cmd, SetOpStrategy strategy, Plan *lefttree,
6481 List *distinctList, AttrNumber flagColIdx, int firstFlag,
6482 long numGroups)
6483 {
6484 SetOp *node = makeNode(SetOp);
6485 Plan *plan = &node->plan;
6486 int numCols = list_length(distinctList);
6487 int keyno = 0;
6488 AttrNumber *dupColIdx;
6489 Oid *dupOperators;
6490 Oid *dupCollations;
6491 ListCell *slitem;
6492
6493 plan->targetlist = lefttree->targetlist;
6494 plan->qual = NIL;
6495 plan->lefttree = lefttree;
6496 plan->righttree = NULL;
6497
6498 /*
6499 * convert SortGroupClause list into arrays of attr indexes and equality
6500 * operators, as wanted by executor
6501 */
6502 dupColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
6503 dupOperators = (Oid *) palloc(sizeof(Oid) * numCols);
6504 dupCollations = (Oid *) palloc(sizeof(Oid) * numCols);
6505
6506 foreach(slitem, distinctList)
6507 {
6508 SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
6509 TargetEntry *tle = get_sortgroupclause_tle(sortcl, plan->targetlist);
6510
6511 dupColIdx[keyno] = tle->resno;
6512 dupOperators[keyno] = sortcl->eqop;
6513 dupCollations[keyno] = exprCollation((Node *) tle->expr);
6514 Assert(OidIsValid(dupOperators[keyno]));
6515 keyno++;
6516 }
6517
6518 node->cmd = cmd;
6519 node->strategy = strategy;
6520 node->numCols = numCols;
6521 node->dupColIdx = dupColIdx;
6522 node->dupOperators = dupOperators;
6523 node->dupCollations = dupCollations;
6524 node->flagColIdx = flagColIdx;
6525 node->firstFlag = firstFlag;
6526 node->numGroups = numGroups;
6527
6528 return node;
6529 }
6530
6531 /*
6532 * make_lockrows
6533 * Build a LockRows plan node
6534 */
6535 static LockRows *
make_lockrows(Plan * lefttree,List * rowMarks,int epqParam)6536 make_lockrows(Plan *lefttree, List *rowMarks, int epqParam)
6537 {
6538 LockRows *node = makeNode(LockRows);
6539 Plan *plan = &node->plan;
6540
6541 plan->targetlist = lefttree->targetlist;
6542 plan->qual = NIL;
6543 plan->lefttree = lefttree;
6544 plan->righttree = NULL;
6545
6546 node->rowMarks = rowMarks;
6547 node->epqParam = epqParam;
6548
6549 return node;
6550 }
6551
6552 /*
6553 * make_limit
6554 * Build a Limit plan node
6555 */
6556 Limit *
make_limit(Plan * lefttree,Node * limitOffset,Node * limitCount)6557 make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount)
6558 {
6559 Limit *node = makeNode(Limit);
6560 Plan *plan = &node->plan;
6561
6562 plan->targetlist = lefttree->targetlist;
6563 plan->qual = NIL;
6564 plan->lefttree = lefttree;
6565 plan->righttree = NULL;
6566
6567 node->limitOffset = limitOffset;
6568 node->limitCount = limitCount;
6569
6570 return node;
6571 }
6572
6573 /*
6574 * make_result
6575 * Build a Result plan node
6576 */
6577 static Result *
make_result(List * tlist,Node * resconstantqual,Plan * subplan)6578 make_result(List *tlist,
6579 Node *resconstantqual,
6580 Plan *subplan)
6581 {
6582 Result *node = makeNode(Result);
6583 Plan *plan = &node->plan;
6584
6585 plan->targetlist = tlist;
6586 plan->qual = NIL;
6587 plan->lefttree = subplan;
6588 plan->righttree = NULL;
6589 node->resconstantqual = resconstantqual;
6590
6591 return node;
6592 }
6593
6594 /*
6595 * make_project_set
6596 * Build a ProjectSet plan node
6597 */
6598 static ProjectSet *
make_project_set(List * tlist,Plan * subplan)6599 make_project_set(List *tlist,
6600 Plan *subplan)
6601 {
6602 ProjectSet *node = makeNode(ProjectSet);
6603 Plan *plan = &node->plan;
6604
6605 plan->targetlist = tlist;
6606 plan->qual = NIL;
6607 plan->lefttree = subplan;
6608 plan->righttree = NULL;
6609
6610 return node;
6611 }
6612
6613 /*
6614 * make_modifytable
6615 * Build a ModifyTable plan node
6616 */
6617 static ModifyTable *
make_modifytable(PlannerInfo * root,CmdType operation,bool canSetTag,Index nominalRelation,Index rootRelation,bool partColsUpdated,List * resultRelations,List * subplans,List * subroots,List * withCheckOptionLists,List * returningLists,List * rowMarks,OnConflictExpr * onconflict,int epqParam)6618 make_modifytable(PlannerInfo *root,
6619 CmdType operation, bool canSetTag,
6620 Index nominalRelation, Index rootRelation,
6621 bool partColsUpdated,
6622 List *resultRelations, List *subplans, List *subroots,
6623 List *withCheckOptionLists, List *returningLists,
6624 List *rowMarks, OnConflictExpr *onconflict, int epqParam)
6625 {
6626 ModifyTable *node = makeNode(ModifyTable);
6627 List *fdw_private_list;
6628 Bitmapset *direct_modify_plans;
6629 ListCell *lc;
6630 ListCell *lc2;
6631 int i;
6632
6633 Assert(list_length(resultRelations) == list_length(subplans));
6634 Assert(list_length(resultRelations) == list_length(subroots));
6635 Assert(withCheckOptionLists == NIL ||
6636 list_length(resultRelations) == list_length(withCheckOptionLists));
6637 Assert(returningLists == NIL ||
6638 list_length(resultRelations) == list_length(returningLists));
6639
6640 node->plan.lefttree = NULL;
6641 node->plan.righttree = NULL;
6642 node->plan.qual = NIL;
6643 /* setrefs.c will fill in the targetlist, if needed */
6644 node->plan.targetlist = NIL;
6645
6646 node->operation = operation;
6647 node->canSetTag = canSetTag;
6648 node->nominalRelation = nominalRelation;
6649 node->rootRelation = rootRelation;
6650 node->partColsUpdated = partColsUpdated;
6651 node->resultRelations = resultRelations;
6652 node->resultRelIndex = -1; /* will be set correctly in setrefs.c */
6653 node->rootResultRelIndex = -1; /* will be set correctly in setrefs.c */
6654 node->plans = subplans;
6655 if (!onconflict)
6656 {
6657 node->onConflictAction = ONCONFLICT_NONE;
6658 node->onConflictSet = NIL;
6659 node->onConflictWhere = NULL;
6660 node->arbiterIndexes = NIL;
6661 node->exclRelRTI = 0;
6662 node->exclRelTlist = NIL;
6663 }
6664 else
6665 {
6666 node->onConflictAction = onconflict->action;
6667 node->onConflictSet = onconflict->onConflictSet;
6668 node->onConflictWhere = onconflict->onConflictWhere;
6669
6670 /*
6671 * If a set of unique index inference elements was provided (an
6672 * INSERT...ON CONFLICT "inference specification"), then infer
6673 * appropriate unique indexes (or throw an error if none are
6674 * available).
6675 */
6676 node->arbiterIndexes = infer_arbiter_indexes(root);
6677
6678 node->exclRelRTI = onconflict->exclRelIndex;
6679 node->exclRelTlist = onconflict->exclRelTlist;
6680 }
6681 node->withCheckOptionLists = withCheckOptionLists;
6682 node->returningLists = returningLists;
6683 node->rowMarks = rowMarks;
6684 node->epqParam = epqParam;
6685
6686 /*
6687 * For each result relation that is a foreign table, allow the FDW to
6688 * construct private plan data, and accumulate it all into a list.
6689 */
6690 fdw_private_list = NIL;
6691 direct_modify_plans = NULL;
6692 i = 0;
6693 forboth(lc, resultRelations, lc2, subroots)
6694 {
6695 Index rti = lfirst_int(lc);
6696 PlannerInfo *subroot = lfirst_node(PlannerInfo, lc2);
6697 FdwRoutine *fdwroutine;
6698 List *fdw_private;
6699 bool direct_modify;
6700
6701 /*
6702 * If possible, we want to get the FdwRoutine from our RelOptInfo for
6703 * the table. But sometimes we don't have a RelOptInfo and must get
6704 * it the hard way. (In INSERT, the target relation is not scanned,
6705 * so it's not a baserel; and there are also corner cases for
6706 * updatable views where the target rel isn't a baserel.)
6707 */
6708 if (rti < subroot->simple_rel_array_size &&
6709 subroot->simple_rel_array[rti] != NULL)
6710 {
6711 RelOptInfo *resultRel = subroot->simple_rel_array[rti];
6712
6713 fdwroutine = resultRel->fdwroutine;
6714 }
6715 else
6716 {
6717 RangeTblEntry *rte = planner_rt_fetch(rti, subroot);
6718
6719 Assert(rte->rtekind == RTE_RELATION);
6720 if (rte->relkind == RELKIND_FOREIGN_TABLE)
6721 fdwroutine = GetFdwRoutineByRelId(rte->relid);
6722 else
6723 fdwroutine = NULL;
6724 }
6725
6726 /*
6727 * Try to modify the foreign table directly if (1) the FDW provides
6728 * callback functions needed for that and (2) there are no local
6729 * structures that need to be run for each modified row: row-level
6730 * triggers on the foreign table, stored generated columns, WITH CHECK
6731 * OPTIONs from parent views.
6732 */
6733 direct_modify = false;
6734 if (fdwroutine != NULL &&
6735 fdwroutine->PlanDirectModify != NULL &&
6736 fdwroutine->BeginDirectModify != NULL &&
6737 fdwroutine->IterateDirectModify != NULL &&
6738 fdwroutine->EndDirectModify != NULL &&
6739 withCheckOptionLists == NIL &&
6740 !has_row_triggers(subroot, rti, operation) &&
6741 !has_stored_generated_columns(subroot, rti))
6742 direct_modify = fdwroutine->PlanDirectModify(subroot, node, rti, i);
6743 if (direct_modify)
6744 direct_modify_plans = bms_add_member(direct_modify_plans, i);
6745
6746 if (!direct_modify &&
6747 fdwroutine != NULL &&
6748 fdwroutine->PlanForeignModify != NULL)
6749 fdw_private = fdwroutine->PlanForeignModify(subroot, node, rti, i);
6750 else
6751 fdw_private = NIL;
6752 fdw_private_list = lappend(fdw_private_list, fdw_private);
6753 i++;
6754 }
6755 node->fdwPrivLists = fdw_private_list;
6756 node->fdwDirectModifyPlans = direct_modify_plans;
6757
6758 return node;
6759 }
6760
6761 /*
6762 * is_projection_capable_path
6763 * Check whether a given Path node is able to do projection.
6764 */
6765 bool
is_projection_capable_path(Path * path)6766 is_projection_capable_path(Path *path)
6767 {
6768 /* Most plan types can project, so just list the ones that can't */
6769 switch (path->pathtype)
6770 {
6771 case T_Hash:
6772 case T_Material:
6773 case T_Sort:
6774 case T_Unique:
6775 case T_SetOp:
6776 case T_LockRows:
6777 case T_Limit:
6778 case T_ModifyTable:
6779 case T_MergeAppend:
6780 case T_RecursiveUnion:
6781 return false;
6782 case T_Append:
6783
6784 /*
6785 * Append can't project, but if an AppendPath is being used to
6786 * represent a dummy path, what will actually be generated is a
6787 * Result which can project.
6788 */
6789 return IS_DUMMY_APPEND(path);
6790 case T_ProjectSet:
6791
6792 /*
6793 * Although ProjectSet certainly projects, say "no" because we
6794 * don't want the planner to randomly replace its tlist with
6795 * something else; the SRFs have to stay at top level. This might
6796 * get relaxed later.
6797 */
6798 return false;
6799 default:
6800 break;
6801 }
6802 return true;
6803 }
6804
6805 /*
6806 * is_projection_capable_plan
6807 * Check whether a given Plan node is able to do projection.
6808 */
6809 bool
is_projection_capable_plan(Plan * plan)6810 is_projection_capable_plan(Plan *plan)
6811 {
6812 /* Most plan types can project, so just list the ones that can't */
6813 switch (nodeTag(plan))
6814 {
6815 case T_Hash:
6816 case T_Material:
6817 case T_Sort:
6818 case T_Unique:
6819 case T_SetOp:
6820 case T_LockRows:
6821 case T_Limit:
6822 case T_ModifyTable:
6823 case T_Append:
6824 case T_MergeAppend:
6825 case T_RecursiveUnion:
6826 return false;
6827 case T_ProjectSet:
6828
6829 /*
6830 * Although ProjectSet certainly projects, say "no" because we
6831 * don't want the planner to randomly replace its tlist with
6832 * something else; the SRFs have to stay at top level. This might
6833 * get relaxed later.
6834 */
6835 return false;
6836 default:
6837 break;
6838 }
6839 return true;
6840 }
6841