Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * subselect.c
4 : * Planning routines for subselects.
5 : *
6 : * This module deals with SubLinks and CTEs, but not subquery RTEs (i.e.,
7 : * not sub-SELECT-in-FROM cases).
8 : *
9 : * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
10 : * Portions Copyright (c) 1994, Regents of the University of California
11 : *
12 : * IDENTIFICATION
13 : * src/backend/optimizer/plan/subselect.c
14 : *
15 : *-------------------------------------------------------------------------
16 : */
17 : #include "postgres.h"
18 :
19 : #include "access/htup_details.h"
20 : #include "catalog/pg_operator.h"
21 : #include "catalog/pg_type.h"
22 : #include "executor/executor.h"
23 : #include "miscadmin.h"
24 : #include "nodes/makefuncs.h"
25 : #include "nodes/nodeFuncs.h"
26 : #include "optimizer/clauses.h"
27 : #include "optimizer/cost.h"
28 : #include "optimizer/optimizer.h"
29 : #include "optimizer/paramassign.h"
30 : #include "optimizer/pathnode.h"
31 : #include "optimizer/planmain.h"
32 : #include "optimizer/planner.h"
33 : #include "optimizer/prep.h"
34 : #include "optimizer/subselect.h"
35 : #include "parser/parse_relation.h"
36 : #include "rewrite/rewriteManip.h"
37 : #include "utils/builtins.h"
38 : #include "utils/lsyscache.h"
39 : #include "utils/syscache.h"
40 :
41 :
42 : typedef struct convert_testexpr_context
43 : {
44 : PlannerInfo *root;
45 : List *subst_nodes; /* Nodes to substitute for Params */
46 : } convert_testexpr_context;
47 :
48 : typedef struct process_sublinks_context
49 : {
50 : PlannerInfo *root;
51 : bool isTopQual;
52 : } process_sublinks_context;
53 :
54 : typedef struct finalize_primnode_context
55 : {
56 : PlannerInfo *root;
57 : Bitmapset *paramids; /* Non-local PARAM_EXEC paramids found */
58 : } finalize_primnode_context;
59 :
60 : typedef struct inline_cte_walker_context
61 : {
62 : const char *ctename; /* name and relative level of target CTE */
63 : int levelsup;
64 : Query *ctequery; /* query to substitute */
65 : } inline_cte_walker_context;
66 :
67 :
68 : static Node *build_subplan(PlannerInfo *root, Plan *plan, Path *path,
69 : PlannerInfo *subroot, List *plan_params,
70 : SubLinkType subLinkType, int subLinkId,
71 : Node *testexpr, List *testexpr_paramids,
72 : bool unknownEqFalse);
73 : static List *generate_subquery_params(PlannerInfo *root, List *tlist,
74 : List **paramIds);
75 : static List *generate_subquery_vars(PlannerInfo *root, List *tlist,
76 : Index varno);
77 : static Node *convert_testexpr(PlannerInfo *root,
78 : Node *testexpr,
79 : List *subst_nodes);
80 : static Node *convert_testexpr_mutator(Node *node,
81 : convert_testexpr_context *context);
82 : static bool subplan_is_hashable(Plan *plan);
83 : static bool subpath_is_hashable(Path *path);
84 : static bool testexpr_is_hashable(Node *testexpr, List *param_ids);
85 : static bool test_opexpr_is_hashable(OpExpr *testexpr, List *param_ids);
86 : static bool hash_ok_operator(OpExpr *expr);
87 : static bool contain_dml(Node *node);
88 : static bool contain_dml_walker(Node *node, void *context);
89 : static bool contain_outer_selfref(Node *node);
90 : static bool contain_outer_selfref_walker(Node *node, Index *depth);
91 : static void inline_cte(PlannerInfo *root, CommonTableExpr *cte);
92 : static bool inline_cte_walker(Node *node, inline_cte_walker_context *context);
93 : static bool simplify_EXISTS_query(PlannerInfo *root, Query *query);
94 : static Query *convert_EXISTS_to_ANY(PlannerInfo *root, Query *subselect,
95 : Node **testexpr, List **paramIds);
96 : static Node *replace_correlation_vars_mutator(Node *node, PlannerInfo *root);
97 : static Node *process_sublinks_mutator(Node *node,
98 : process_sublinks_context *context);
99 : static Bitmapset *finalize_plan(PlannerInfo *root,
100 : Plan *plan,
101 : int gather_param,
102 : Bitmapset *valid_params,
103 : Bitmapset *scan_params);
104 : static bool finalize_primnode(Node *node, finalize_primnode_context *context);
105 : static bool finalize_agg_primnode(Node *node, finalize_primnode_context *context);
106 :
107 :
108 : /*
109 : * Get the datatype/typmod/collation of the first column of the plan's output.
110 : *
111 : * This information is stored for ARRAY_SUBLINK execution and for
112 : * exprType()/exprTypmod()/exprCollation(), which have no way to get at the
113 : * plan associated with a SubPlan node. We really only need the info for
114 : * EXPR_SUBLINK and ARRAY_SUBLINK subplans, but for consistency we save it
115 : * always.
116 : */
117 : static void
118 38610 : get_first_col_type(Plan *plan, Oid *coltype, int32 *coltypmod,
119 : Oid *colcollation)
120 : {
121 : /* In cases such as EXISTS, tlist might be empty; arbitrarily use VOID */
122 38610 : if (plan->targetlist)
123 : {
124 36274 : TargetEntry *tent = linitial_node(TargetEntry, plan->targetlist);
125 :
126 36274 : if (!tent->resjunk)
127 : {
128 36274 : *coltype = exprType((Node *) tent->expr);
129 36274 : *coltypmod = exprTypmod((Node *) tent->expr);
130 36274 : *colcollation = exprCollation((Node *) tent->expr);
131 36274 : return;
132 : }
133 : }
134 2336 : *coltype = VOIDOID;
135 2336 : *coltypmod = -1;
136 2336 : *colcollation = InvalidOid;
137 : }
138 :
139 : /*
140 : * Convert a SubLink (as created by the parser) into a SubPlan.
141 : *
142 : * We are given the SubLink's contained query, type, ID, and testexpr. We are
143 : * also told if this expression appears at top level of a WHERE/HAVING qual.
144 : *
145 : * Note: we assume that the testexpr has been AND/OR flattened (actually,
146 : * it's been through eval_const_expressions), but not converted to
147 : * implicit-AND form; and any SubLinks in it should already have been
148 : * converted to SubPlans. The subquery is as yet untouched, however.
149 : *
150 : * The result is whatever we need to substitute in place of the SubLink node
151 : * in the executable expression. If we're going to do the subplan as a
152 : * regular subplan, this will be the constructed SubPlan node. If we're going
153 : * to do the subplan as an InitPlan, the SubPlan node instead goes into
154 : * root->init_plans, and what we return here is an expression tree
155 : * representing the InitPlan's result: usually just a Param node representing
156 : * a single scalar result, but possibly a row comparison tree containing
157 : * multiple Param nodes, or for a MULTIEXPR subquery a simple NULL constant
158 : * (since the real output Params are elsewhere in the tree, and the MULTIEXPR
159 : * subquery itself is in a resjunk tlist entry whose value is uninteresting).
160 : */
161 : static Node *
162 34672 : make_subplan(PlannerInfo *root, Query *orig_subquery,
163 : SubLinkType subLinkType, int subLinkId,
164 : Node *testexpr, bool isTopQual)
165 : {
166 : Query *subquery;
167 34672 : bool simple_exists = false;
168 : double tuple_fraction;
169 : PlannerInfo *subroot;
170 : RelOptInfo *final_rel;
171 : Path *best_path;
172 : Plan *plan;
173 : List *plan_params;
174 : Node *result;
175 :
176 : /*
177 : * Copy the source Query node. This is a quick and dirty kluge to resolve
178 : * the fact that the parser can generate trees with multiple links to the
179 : * same sub-Query node, but the planner wants to scribble on the Query.
180 : * Try to clean this up when we do querytree redesign...
181 : */
182 34672 : subquery = copyObject(orig_subquery);
183 :
184 : /*
185 : * If it's an EXISTS subplan, we might be able to simplify it.
186 : */
187 34672 : if (subLinkType == EXISTS_SUBLINK)
188 2098 : simple_exists = simplify_EXISTS_query(root, subquery);
189 :
190 : /*
191 : * For an EXISTS subplan, tell lower-level planner to expect that only the
192 : * first tuple will be retrieved. For ALL and ANY subplans, we will be
193 : * able to stop evaluating if the test condition fails or matches, so very
194 : * often not all the tuples will be retrieved; for lack of a better idea,
195 : * specify 50% retrieval. For EXPR, MULTIEXPR, and ROWCOMPARE subplans,
196 : * use default behavior (we're only expecting one row out, anyway).
197 : *
198 : * NOTE: if you change these numbers, also change cost_subplan() in
199 : * path/costsize.c.
200 : *
201 : * XXX If an ANY subplan is uncorrelated, build_subplan may decide to hash
202 : * its output. In that case it would've been better to specify full
203 : * retrieval. At present, however, we can only check hashability after
204 : * we've made the subplan :-(. (Determining whether it'll fit in hash_mem
205 : * is the really hard part.) Therefore, we don't want to be too
206 : * optimistic about the percentage of tuples retrieved, for fear of
207 : * selecting a plan that's bad for the materialization case.
208 : */
209 34672 : if (subLinkType == EXISTS_SUBLINK)
210 2098 : tuple_fraction = 1.0; /* just like a LIMIT 1 */
211 32574 : else if (subLinkType == ALL_SUBLINK ||
212 : subLinkType == ANY_SUBLINK)
213 492 : tuple_fraction = 0.5; /* 50% */
214 : else
215 32082 : tuple_fraction = 0.0; /* default behavior */
216 :
217 : /* plan_params should not be in use in current query level */
218 : Assert(root->plan_params == NIL);
219 :
220 : /* Generate Paths for the subquery */
221 34672 : subroot = subquery_planner(root->glob, subquery, root, false,
222 : tuple_fraction, NULL);
223 :
224 : /* Isolate the params needed by this specific subplan */
225 34672 : plan_params = root->plan_params;
226 34672 : root->plan_params = NIL;
227 :
228 : /*
229 : * Select best Path and turn it into a Plan. At least for now, there
230 : * seems no reason to postpone doing that.
231 : */
232 34672 : final_rel = fetch_upper_rel(subroot, UPPERREL_FINAL, NULL);
233 34672 : best_path = get_cheapest_fractional_path(final_rel, tuple_fraction);
234 :
235 34672 : plan = create_plan(subroot, best_path);
236 :
237 : /* And convert to SubPlan or InitPlan format. */
238 34672 : result = build_subplan(root, plan, best_path,
239 : subroot, plan_params,
240 : subLinkType, subLinkId,
241 : testexpr, NIL, isTopQual);
242 :
243 : /*
244 : * If it's a correlated EXISTS with an unimportant targetlist, we might be
245 : * able to transform it to the equivalent of an IN and then implement it
246 : * by hashing. We don't have enough information yet to tell which way is
247 : * likely to be better (it depends on the expected number of executions of
248 : * the EXISTS qual, and we are much too early in planning the outer query
249 : * to be able to guess that). So we generate both plans, if possible, and
250 : * leave it to setrefs.c to decide which to use.
251 : */
252 34672 : if (simple_exists && IsA(result, SubPlan))
253 : {
254 : Node *newtestexpr;
255 : List *paramIds;
256 :
257 : /* Make a second copy of the original subquery */
258 1814 : subquery = copyObject(orig_subquery);
259 : /* and re-simplify */
260 1814 : simple_exists = simplify_EXISTS_query(root, subquery);
261 : Assert(simple_exists);
262 : /* See if it can be converted to an ANY query */
263 1814 : subquery = convert_EXISTS_to_ANY(root, subquery,
264 : &newtestexpr, ¶mIds);
265 1814 : if (subquery)
266 : {
267 : /* Generate Paths for the ANY subquery; we'll need all rows */
268 1500 : subroot = subquery_planner(root->glob, subquery, root, false, 0.0,
269 : NULL);
270 :
271 : /* Isolate the params needed by this specific subplan */
272 1500 : plan_params = root->plan_params;
273 1500 : root->plan_params = NIL;
274 :
275 : /* Select best Path */
276 1500 : final_rel = fetch_upper_rel(subroot, UPPERREL_FINAL, NULL);
277 1500 : best_path = final_rel->cheapest_total_path;
278 :
279 : /* Now we can check if it'll fit in hash_mem */
280 1500 : if (subpath_is_hashable(best_path))
281 : {
282 : SubPlan *hashplan;
283 : AlternativeSubPlan *asplan;
284 :
285 : /* OK, finish planning the ANY subquery */
286 1500 : plan = create_plan(subroot, best_path);
287 :
288 : /* ... and convert to SubPlan format */
289 1500 : hashplan = castNode(SubPlan,
290 : build_subplan(root, plan, best_path,
291 : subroot, plan_params,
292 : ANY_SUBLINK, 0,
293 : newtestexpr,
294 : paramIds,
295 : true));
296 : /* Check we got what we expected */
297 : Assert(hashplan->parParam == NIL);
298 : Assert(hashplan->useHashTable);
299 :
300 : /* Leave it to setrefs.c to decide which plan to use */
301 1500 : asplan = makeNode(AlternativeSubPlan);
302 1500 : asplan->subplans = list_make2(result, hashplan);
303 1500 : result = (Node *) asplan;
304 1500 : root->hasAlternativeSubPlans = true;
305 : }
306 : }
307 : }
308 :
309 34672 : return result;
310 : }
311 :
312 : /*
313 : * Build a SubPlan node given the raw inputs --- subroutine for make_subplan
314 : *
315 : * Returns either the SubPlan, or a replacement expression if we decide to
316 : * make it an InitPlan, as explained in the comments for make_subplan.
317 : */
318 : static Node *
319 36172 : build_subplan(PlannerInfo *root, Plan *plan, Path *path,
320 : PlannerInfo *subroot, List *plan_params,
321 : SubLinkType subLinkType, int subLinkId,
322 : Node *testexpr, List *testexpr_paramids,
323 : bool unknownEqFalse)
324 : {
325 : Node *result;
326 : SubPlan *splan;
327 : bool isInitPlan;
328 : ListCell *lc;
329 :
330 : /*
331 : * Initialize the SubPlan node. Note plan_id, plan_name, and cost fields
332 : * are set further down.
333 : */
334 36172 : splan = makeNode(SubPlan);
335 36172 : splan->subLinkType = subLinkType;
336 36172 : splan->testexpr = NULL;
337 36172 : splan->paramIds = NIL;
338 36172 : get_first_col_type(plan, &splan->firstColType, &splan->firstColTypmod,
339 : &splan->firstColCollation);
340 36172 : splan->useHashTable = false;
341 36172 : splan->unknownEqFalse = unknownEqFalse;
342 36172 : splan->parallel_safe = plan->parallel_safe;
343 36172 : splan->setParam = NIL;
344 36172 : splan->parParam = NIL;
345 36172 : splan->args = NIL;
346 :
347 : /*
348 : * Make parParam and args lists of param IDs and expressions that current
349 : * query level will pass to this child plan.
350 : */
351 76440 : foreach(lc, plan_params)
352 : {
353 40268 : PlannerParamItem *pitem = (PlannerParamItem *) lfirst(lc);
354 40268 : Node *arg = pitem->item;
355 :
356 : /*
357 : * The Var, PlaceHolderVar, Aggref or GroupingFunc has already been
358 : * adjusted to have the correct varlevelsup, phlevelsup, or
359 : * agglevelsup.
360 : *
361 : * If it's a PlaceHolderVar, Aggref or GroupingFunc, its arguments
362 : * might contain SubLinks, which have not yet been processed (see the
363 : * comments for SS_replace_correlation_vars). Do that now.
364 : */
365 40268 : if (IsA(arg, PlaceHolderVar) ||
366 40256 : IsA(arg, Aggref) ||
367 40204 : IsA(arg, GroupingFunc))
368 128 : arg = SS_process_sublinks(root, arg, false);
369 :
370 40268 : splan->parParam = lappend_int(splan->parParam, pitem->paramId);
371 40268 : splan->args = lappend(splan->args, arg);
372 : }
373 :
374 : /*
375 : * Un-correlated or undirect correlated plans of EXISTS, EXPR, ARRAY,
376 : * ROWCOMPARE, or MULTIEXPR types can be used as initPlans. For EXISTS,
377 : * EXPR, or ARRAY, we return a Param referring to the result of evaluating
378 : * the initPlan. For ROWCOMPARE, we must modify the testexpr tree to
379 : * contain PARAM_EXEC Params instead of the PARAM_SUBLINK Params emitted
380 : * by the parser, and then return that tree. For MULTIEXPR, we return a
381 : * null constant: the resjunk targetlist item containing the SubLink does
382 : * not need to return anything useful, since the referencing Params are
383 : * elsewhere.
384 : */
385 36172 : if (splan->parParam == NIL && subLinkType == EXISTS_SUBLINK)
386 252 : {
387 : Param *prm;
388 :
389 : Assert(testexpr == NULL);
390 252 : prm = generate_new_exec_param(root, BOOLOID, -1, InvalidOid);
391 252 : splan->setParam = list_make1_int(prm->paramid);
392 252 : isInitPlan = true;
393 252 : result = (Node *) prm;
394 : }
395 35920 : else if (splan->parParam == NIL && subLinkType == EXPR_SUBLINK)
396 8610 : {
397 8610 : TargetEntry *te = linitial(plan->targetlist);
398 : Param *prm;
399 :
400 : Assert(!te->resjunk);
401 : Assert(testexpr == NULL);
402 8610 : prm = generate_new_exec_param(root,
403 8610 : exprType((Node *) te->expr),
404 8610 : exprTypmod((Node *) te->expr),
405 8610 : exprCollation((Node *) te->expr));
406 8610 : splan->setParam = list_make1_int(prm->paramid);
407 8610 : isInitPlan = true;
408 8610 : result = (Node *) prm;
409 : }
410 27310 : else if (splan->parParam == NIL && subLinkType == ARRAY_SUBLINK)
411 80 : {
412 80 : TargetEntry *te = linitial(plan->targetlist);
413 : Oid arraytype;
414 : Param *prm;
415 :
416 : Assert(!te->resjunk);
417 : Assert(testexpr == NULL);
418 80 : arraytype = get_promoted_array_type(exprType((Node *) te->expr));
419 80 : if (!OidIsValid(arraytype))
420 0 : elog(ERROR, "could not find array type for datatype %s",
421 : format_type_be(exprType((Node *) te->expr)));
422 80 : prm = generate_new_exec_param(root,
423 : arraytype,
424 80 : exprTypmod((Node *) te->expr),
425 80 : exprCollation((Node *) te->expr));
426 80 : splan->setParam = list_make1_int(prm->paramid);
427 80 : isInitPlan = true;
428 80 : result = (Node *) prm;
429 : }
430 27230 : else if (splan->parParam == NIL && subLinkType == ROWCOMPARE_SUBLINK)
431 18 : {
432 : /* Adjust the Params */
433 : List *params;
434 :
435 : Assert(testexpr != NULL);
436 18 : params = generate_subquery_params(root,
437 : plan->targetlist,
438 : &splan->paramIds);
439 18 : result = convert_testexpr(root,
440 : testexpr,
441 : params);
442 18 : splan->setParam = list_copy(splan->paramIds);
443 18 : isInitPlan = true;
444 :
445 : /*
446 : * The executable expression is returned to become part of the outer
447 : * plan's expression tree; it is not kept in the initplan node.
448 : */
449 : }
450 27212 : else if (subLinkType == MULTIEXPR_SUBLINK)
451 : {
452 : /*
453 : * Whether it's an initplan or not, it needs to set a PARAM_EXEC Param
454 : * for each output column.
455 : */
456 : List *params;
457 :
458 : Assert(testexpr == NULL);
459 132 : params = generate_subquery_params(root,
460 : plan->targetlist,
461 : &splan->setParam);
462 :
463 : /*
464 : * Save the list of replacement Params in the n'th cell of
465 : * root->multiexpr_params; setrefs.c will use it to replace
466 : * PARAM_MULTIEXPR Params.
467 : */
468 264 : while (list_length(root->multiexpr_params) < subLinkId)
469 132 : root->multiexpr_params = lappend(root->multiexpr_params, NIL);
470 132 : lc = list_nth_cell(root->multiexpr_params, subLinkId - 1);
471 : Assert(lfirst(lc) == NIL);
472 132 : lfirst(lc) = params;
473 :
474 : /* It can be an initplan if there are no parParams. */
475 132 : if (splan->parParam == NIL)
476 : {
477 30 : isInitPlan = true;
478 30 : result = (Node *) makeNullConst(RECORDOID, -1, InvalidOid);
479 : }
480 : else
481 : {
482 102 : isInitPlan = false;
483 102 : result = (Node *) splan;
484 : }
485 : }
486 : else
487 : {
488 : /*
489 : * Adjust the Params in the testexpr, unless caller already took care
490 : * of it (as indicated by passing a list of Param IDs).
491 : */
492 27080 : if (testexpr && testexpr_paramids == NIL)
493 504 : {
494 : List *params;
495 :
496 504 : params = generate_subquery_params(root,
497 : plan->targetlist,
498 : &splan->paramIds);
499 504 : splan->testexpr = convert_testexpr(root,
500 : testexpr,
501 : params);
502 : }
503 : else
504 : {
505 26576 : splan->testexpr = testexpr;
506 26576 : splan->paramIds = testexpr_paramids;
507 : }
508 :
509 : /*
510 : * We can't convert subplans of ALL_SUBLINK or ANY_SUBLINK types to
511 : * initPlans, even when they are uncorrelated or undirect correlated,
512 : * because we need to scan the output of the subplan for each outer
513 : * tuple. But if it's a not-direct-correlated IN (= ANY) test, we
514 : * might be able to use a hashtable to avoid comparing all the tuples.
515 : */
516 27080 : if (subLinkType == ANY_SUBLINK &&
517 3890 : splan->parParam == NIL &&
518 3832 : subplan_is_hashable(plan) &&
519 1916 : testexpr_is_hashable(splan->testexpr, splan->paramIds))
520 1892 : splan->useHashTable = true;
521 :
522 : /*
523 : * Otherwise, we have the option to tack a Material node onto the top
524 : * of the subplan, to reduce the cost of reading it repeatedly. This
525 : * is pointless for a direct-correlated subplan, since we'd have to
526 : * recompute its results each time anyway. For uncorrelated/undirect
527 : * correlated subplans, we add Material unless the subplan's top plan
528 : * node would materialize its output anyway. Also, if enable_material
529 : * is false, then the user does not want us to materialize anything
530 : * unnecessarily, so we don't.
531 : */
532 25188 : else if (splan->parParam == NIL && enable_material &&
533 42 : !ExecMaterializesOutput(nodeTag(plan)))
534 42 : plan = materialize_finished_plan(plan);
535 :
536 27080 : result = (Node *) splan;
537 27080 : isInitPlan = false;
538 : }
539 :
540 : /*
541 : * Add the subplan, its path, and its PlannerInfo to the global lists.
542 : */
543 36172 : root->glob->subplans = lappend(root->glob->subplans, plan);
544 36172 : root->glob->subpaths = lappend(root->glob->subpaths, path);
545 36172 : root->glob->subroots = lappend(root->glob->subroots, subroot);
546 36172 : splan->plan_id = list_length(root->glob->subplans);
547 :
548 36172 : if (isInitPlan)
549 8990 : root->init_plans = lappend(root->init_plans, splan);
550 :
551 : /*
552 : * A parameterless subplan (not initplan) should be prepared to handle
553 : * REWIND efficiently. If it has direct parameters then there's no point
554 : * since it'll be reset on each scan anyway; and if it's an initplan then
555 : * there's no point since it won't get re-run without parameter changes
556 : * anyway. The input of a hashed subplan doesn't need REWIND either.
557 : */
558 36172 : if (splan->parParam == NIL && !isInitPlan && !splan->useHashTable)
559 42 : root->glob->rewindPlanIDs = bms_add_member(root->glob->rewindPlanIDs,
560 : splan->plan_id);
561 :
562 : /* Label the subplan for EXPLAIN purposes */
563 36172 : splan->plan_name = psprintf("%s %d",
564 : isInitPlan ? "InitPlan" : "SubPlan",
565 : splan->plan_id);
566 :
567 : /* Lastly, fill in the cost estimates for use later */
568 36172 : cost_subplan(root, splan, plan);
569 :
570 36172 : return result;
571 : }
572 :
573 : /*
574 : * generate_subquery_params: build a list of Params representing the output
575 : * columns of a sublink's sub-select, given the sub-select's targetlist.
576 : *
577 : * We also return an integer list of the paramids of the Params.
578 : */
579 : static List *
580 654 : generate_subquery_params(PlannerInfo *root, List *tlist, List **paramIds)
581 : {
582 : List *result;
583 : List *ids;
584 : ListCell *lc;
585 :
586 654 : result = ids = NIL;
587 1556 : foreach(lc, tlist)
588 : {
589 902 : TargetEntry *tent = (TargetEntry *) lfirst(lc);
590 : Param *param;
591 :
592 902 : if (tent->resjunk)
593 6 : continue;
594 :
595 896 : param = generate_new_exec_param(root,
596 896 : exprType((Node *) tent->expr),
597 896 : exprTypmod((Node *) tent->expr),
598 896 : exprCollation((Node *) tent->expr));
599 896 : result = lappend(result, param);
600 896 : ids = lappend_int(ids, param->paramid);
601 : }
602 :
603 654 : *paramIds = ids;
604 654 : return result;
605 : }
606 :
607 : /*
608 : * generate_subquery_vars: build a list of Vars representing the output
609 : * columns of a sublink's sub-select, given the sub-select's targetlist.
610 : * The Vars have the specified varno (RTE index).
611 : */
612 : static List *
613 1408 : generate_subquery_vars(PlannerInfo *root, List *tlist, Index varno)
614 : {
615 : List *result;
616 : ListCell *lc;
617 :
618 1408 : result = NIL;
619 2864 : foreach(lc, tlist)
620 : {
621 1456 : TargetEntry *tent = (TargetEntry *) lfirst(lc);
622 : Var *var;
623 :
624 1456 : if (tent->resjunk)
625 0 : continue;
626 :
627 1456 : var = makeVarFromTargetEntry(varno, tent);
628 1456 : result = lappend(result, var);
629 : }
630 :
631 1408 : return result;
632 : }
633 :
634 : /*
635 : * convert_testexpr: convert the testexpr given by the parser into
636 : * actually executable form. This entails replacing PARAM_SUBLINK Params
637 : * with Params or Vars representing the results of the sub-select. The
638 : * nodes to be substituted are passed in as the List result from
639 : * generate_subquery_params or generate_subquery_vars.
640 : */
641 : static Node *
642 1930 : convert_testexpr(PlannerInfo *root,
643 : Node *testexpr,
644 : List *subst_nodes)
645 : {
646 : convert_testexpr_context context;
647 :
648 1930 : context.root = root;
649 1930 : context.subst_nodes = subst_nodes;
650 1930 : return convert_testexpr_mutator(testexpr, &context);
651 : }
652 :
653 : static Node *
654 9798 : convert_testexpr_mutator(Node *node,
655 : convert_testexpr_context *context)
656 : {
657 9798 : if (node == NULL)
658 46 : return NULL;
659 9752 : if (IsA(node, Param))
660 : {
661 2102 : Param *param = (Param *) node;
662 :
663 2102 : if (param->paramkind == PARAM_SUBLINK)
664 : {
665 4204 : if (param->paramid <= 0 ||
666 2102 : param->paramid > list_length(context->subst_nodes))
667 0 : elog(ERROR, "unexpected PARAM_SUBLINK ID: %d", param->paramid);
668 :
669 : /*
670 : * We copy the list item to avoid having doubly-linked
671 : * substructure in the modified parse tree. This is probably
672 : * unnecessary when it's a Param, but be safe.
673 : */
674 2102 : return (Node *) copyObject(list_nth(context->subst_nodes,
675 : param->paramid - 1));
676 : }
677 : }
678 7650 : if (IsA(node, SubLink))
679 : {
680 : /*
681 : * If we come across a nested SubLink, it is neither necessary nor
682 : * correct to recurse into it: any PARAM_SUBLINKs we might find inside
683 : * belong to the inner SubLink not the outer. So just return it as-is.
684 : *
685 : * This reasoning depends on the assumption that nothing will pull
686 : * subexpressions into or out of the testexpr field of a SubLink, at
687 : * least not without replacing PARAM_SUBLINKs first. If we did want
688 : * to do that we'd need to rethink the parser-output representation
689 : * altogether, since currently PARAM_SUBLINKs are only unique per
690 : * SubLink not globally across the query. The whole point of
691 : * replacing them with Vars or PARAM_EXEC nodes is to make them
692 : * globally unique before they escape from the SubLink's testexpr.
693 : *
694 : * Note: this can't happen when called during SS_process_sublinks,
695 : * because that recursively processes inner SubLinks first. It can
696 : * happen when called from convert_ANY_sublink_to_join, though.
697 : */
698 12 : return node;
699 : }
700 7638 : return expression_tree_mutator(node,
701 : convert_testexpr_mutator,
702 : (void *) context);
703 : }
704 :
705 : /*
706 : * subplan_is_hashable: can we implement an ANY subplan by hashing?
707 : *
708 : * This is not responsible for checking whether the combining testexpr
709 : * is suitable for hashing. We only look at the subquery itself.
710 : */
711 : static bool
712 1916 : subplan_is_hashable(Plan *plan)
713 : {
714 : double subquery_size;
715 :
716 : /*
717 : * The estimated size of the subquery result must fit in hash_mem. (Note:
718 : * we use heap tuple overhead here even though the tuples will actually be
719 : * stored as MinimalTuples; this provides some fudge factor for hashtable
720 : * overhead.)
721 : */
722 1916 : subquery_size = plan->plan_rows *
723 1916 : (MAXALIGN(plan->plan_width) + MAXALIGN(SizeofHeapTupleHeader));
724 1916 : if (subquery_size > get_hash_memory_limit())
725 0 : return false;
726 :
727 1916 : return true;
728 : }
729 :
730 : /*
731 : * subpath_is_hashable: can we implement an ANY subplan by hashing?
732 : *
733 : * Identical to subplan_is_hashable, but work from a Path for the subplan.
734 : */
735 : static bool
736 1500 : subpath_is_hashable(Path *path)
737 : {
738 : double subquery_size;
739 :
740 : /*
741 : * The estimated size of the subquery result must fit in hash_mem. (Note:
742 : * we use heap tuple overhead here even though the tuples will actually be
743 : * stored as MinimalTuples; this provides some fudge factor for hashtable
744 : * overhead.)
745 : */
746 1500 : subquery_size = path->rows *
747 1500 : (MAXALIGN(path->pathtarget->width) + MAXALIGN(SizeofHeapTupleHeader));
748 1500 : if (subquery_size > get_hash_memory_limit())
749 0 : return false;
750 :
751 1500 : return true;
752 : }
753 :
754 : /*
755 : * testexpr_is_hashable: is an ANY SubLink's test expression hashable?
756 : *
757 : * To identify LHS vs RHS of the hash expression, we must be given the
758 : * list of output Param IDs of the SubLink's subquery.
759 : */
760 : static bool
761 1916 : testexpr_is_hashable(Node *testexpr, List *param_ids)
762 : {
763 : /*
764 : * The testexpr must be a single OpExpr, or an AND-clause containing only
765 : * OpExprs, each of which satisfy test_opexpr_is_hashable().
766 : */
767 1916 : if (testexpr && IsA(testexpr, OpExpr))
768 : {
769 1074 : if (test_opexpr_is_hashable((OpExpr *) testexpr, param_ids))
770 1050 : return true;
771 : }
772 842 : else if (is_andclause(testexpr))
773 : {
774 : ListCell *l;
775 :
776 2526 : foreach(l, ((BoolExpr *) testexpr)->args)
777 : {
778 1684 : Node *andarg = (Node *) lfirst(l);
779 :
780 1684 : if (!IsA(andarg, OpExpr))
781 0 : return false;
782 1684 : if (!test_opexpr_is_hashable((OpExpr *) andarg, param_ids))
783 0 : return false;
784 : }
785 842 : return true;
786 : }
787 :
788 24 : return false;
789 : }
790 :
791 : static bool
792 2758 : test_opexpr_is_hashable(OpExpr *testexpr, List *param_ids)
793 : {
794 : /*
795 : * The combining operator must be hashable and strict. The need for
796 : * hashability is obvious, since we want to use hashing. Without
797 : * strictness, behavior in the presence of nulls is too unpredictable. We
798 : * actually must assume even more than plain strictness: it can't yield
799 : * NULL for non-null inputs, either (see nodeSubplan.c). However, hash
800 : * indexes and hash joins assume that too.
801 : */
802 2758 : if (!hash_ok_operator(testexpr))
803 12 : return false;
804 :
805 : /*
806 : * The left and right inputs must belong to the outer and inner queries
807 : * respectively; hence Params that will be supplied by the subquery must
808 : * not appear in the LHS, and Vars of the outer query must not appear in
809 : * the RHS. (Ordinarily, this must be true because of the way that the
810 : * parser builds an ANY SubLink's testexpr ... but inlining of functions
811 : * could have changed the expression's structure, so we have to check.
812 : * Such cases do not occur often enough to be worth trying to optimize, so
813 : * we don't worry about trying to commute the clause or anything like
814 : * that; we just need to be sure not to build an invalid plan.)
815 : */
816 2746 : if (list_length(testexpr->args) != 2)
817 0 : return false;
818 2746 : if (contain_exec_param((Node *) linitial(testexpr->args), param_ids))
819 12 : return false;
820 2734 : if (contain_var_clause((Node *) lsecond(testexpr->args)))
821 0 : return false;
822 2734 : return true;
823 : }
824 :
825 : /*
826 : * Check expression is hashable + strict
827 : *
828 : * We could use op_hashjoinable() and op_strict(), but do it like this to
829 : * avoid a redundant cache lookup.
830 : */
831 : static bool
832 7930 : hash_ok_operator(OpExpr *expr)
833 : {
834 7930 : Oid opid = expr->opno;
835 :
836 : /* quick out if not a binary operator */
837 7930 : if (list_length(expr->args) != 2)
838 0 : return false;
839 7930 : if (opid == ARRAY_EQ_OP ||
840 : opid == RECORD_EQ_OP)
841 : {
842 : /* these are strict, but must check input type to ensure hashable */
843 12 : Node *leftarg = linitial(expr->args);
844 :
845 12 : return op_hashjoinable(opid, exprType(leftarg));
846 : }
847 : else
848 : {
849 : /* else must look up the operator properties */
850 : HeapTuple tup;
851 : Form_pg_operator optup;
852 :
853 7918 : tup = SearchSysCache1(OPEROID, ObjectIdGetDatum(opid));
854 7918 : if (!HeapTupleIsValid(tup))
855 0 : elog(ERROR, "cache lookup failed for operator %u", opid);
856 7918 : optup = (Form_pg_operator) GETSTRUCT(tup);
857 7918 : if (!optup->oprcanhash || !func_strict(optup->oprcode))
858 : {
859 622 : ReleaseSysCache(tup);
860 622 : return false;
861 : }
862 7296 : ReleaseSysCache(tup);
863 7296 : return true;
864 : }
865 : }
866 :
867 :
868 : /*
869 : * SS_process_ctes: process a query's WITH list
870 : *
871 : * Consider each CTE in the WITH list and either ignore it (if it's an
872 : * unreferenced SELECT), "inline" it to create a regular sub-SELECT-in-FROM,
873 : * or convert it to an initplan.
874 : *
875 : * A side effect is to fill in root->cte_plan_ids with a list that
876 : * parallels root->parse->cteList and provides the subplan ID for
877 : * each CTE's initplan, or a dummy ID (-1) if we didn't make an initplan.
878 : */
879 : void
880 2458 : SS_process_ctes(PlannerInfo *root)
881 : {
882 : ListCell *lc;
883 :
884 : Assert(root->cte_plan_ids == NIL);
885 :
886 5894 : foreach(lc, root->parse->cteList)
887 : {
888 3442 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
889 3442 : CmdType cmdType = ((Query *) cte->ctequery)->commandType;
890 : Query *subquery;
891 : PlannerInfo *subroot;
892 : RelOptInfo *final_rel;
893 : Path *best_path;
894 : Plan *plan;
895 : SubPlan *splan;
896 : int paramid;
897 :
898 : /*
899 : * Ignore SELECT CTEs that are not actually referenced anywhere.
900 : */
901 3442 : if (cte->cterefcount == 0 && cmdType == CMD_SELECT)
902 : {
903 : /* Make a dummy entry in cte_plan_ids */
904 46 : root->cte_plan_ids = lappend_int(root->cte_plan_ids, -1);
905 1398 : continue;
906 : }
907 :
908 : /*
909 : * Consider inlining the CTE (creating RTE_SUBQUERY RTE(s)) instead of
910 : * implementing it as a separately-planned CTE.
911 : *
912 : * We cannot inline if any of these conditions hold:
913 : *
914 : * 1. The user said not to (the CTEMaterializeAlways option).
915 : *
916 : * 2. The CTE is recursive.
917 : *
918 : * 3. The CTE has side-effects; this includes either not being a plain
919 : * SELECT, or containing volatile functions. Inlining might change
920 : * the side-effects, which would be bad.
921 : *
922 : * 4. The CTE is multiply-referenced and contains a self-reference to
923 : * a recursive CTE outside itself. Inlining would result in multiple
924 : * recursive self-references, which we don't support.
925 : *
926 : * Otherwise, we have an option whether to inline or not. That should
927 : * always be a win if there's just a single reference, but if the CTE
928 : * is multiply-referenced then it's unclear: inlining adds duplicate
929 : * computations, but the ability to absorb restrictions from the outer
930 : * query level could outweigh that. We do not have nearly enough
931 : * information at this point to tell whether that's true, so we let
932 : * the user express a preference. Our default behavior is to inline
933 : * only singly-referenced CTEs, but a CTE marked CTEMaterializeNever
934 : * will be inlined even if multiply referenced.
935 : *
936 : * Note: we check for volatile functions last, because that's more
937 : * expensive than the other tests needed.
938 : */
939 3396 : if ((cte->ctematerialized == CTEMaterializeNever ||
940 3348 : (cte->ctematerialized == CTEMaterializeDefault &&
941 3146 : cte->cterefcount == 1)) &&
942 2438 : !cte->cterecursive &&
943 1438 : cmdType == CMD_SELECT &&
944 1438 : !contain_dml(cte->ctequery) &&
945 1430 : (cte->cterefcount <= 1 ||
946 36 : !contain_outer_selfref(cte->ctequery)) &&
947 1418 : !contain_volatile_functions(cte->ctequery))
948 : {
949 1352 : inline_cte(root, cte);
950 : /* Make a dummy entry in cte_plan_ids */
951 1352 : root->cte_plan_ids = lappend_int(root->cte_plan_ids, -1);
952 1352 : continue;
953 : }
954 :
955 : /*
956 : * Copy the source Query node. Probably not necessary, but let's keep
957 : * this similar to make_subplan.
958 : */
959 2044 : subquery = (Query *) copyObject(cte->ctequery);
960 :
961 : /* plan_params should not be in use in current query level */
962 : Assert(root->plan_params == NIL);
963 :
964 : /*
965 : * Generate Paths for the CTE query. Always plan for full retrieval
966 : * --- we don't have enough info to predict otherwise.
967 : */
968 2044 : subroot = subquery_planner(root->glob, subquery, root,
969 2044 : cte->cterecursive, 0.0, NULL);
970 :
971 : /*
972 : * Since the current query level doesn't yet contain any RTEs, it
973 : * should not be possible for the CTE to have requested parameters of
974 : * this level.
975 : */
976 2038 : if (root->plan_params)
977 0 : elog(ERROR, "unexpected outer reference in CTE query");
978 :
979 : /*
980 : * Select best Path and turn it into a Plan. At least for now, there
981 : * seems no reason to postpone doing that.
982 : */
983 2038 : final_rel = fetch_upper_rel(subroot, UPPERREL_FINAL, NULL);
984 2038 : best_path = final_rel->cheapest_total_path;
985 :
986 2038 : plan = create_plan(subroot, best_path);
987 :
988 : /*
989 : * Make a SubPlan node for it. This is just enough unlike
990 : * build_subplan that we can't share code.
991 : *
992 : * Note plan_id, plan_name, and cost fields are set further down.
993 : */
994 2038 : splan = makeNode(SubPlan);
995 2038 : splan->subLinkType = CTE_SUBLINK;
996 2038 : splan->testexpr = NULL;
997 2038 : splan->paramIds = NIL;
998 2038 : get_first_col_type(plan, &splan->firstColType, &splan->firstColTypmod,
999 : &splan->firstColCollation);
1000 2038 : splan->useHashTable = false;
1001 2038 : splan->unknownEqFalse = false;
1002 :
1003 : /*
1004 : * CTE scans are not considered for parallelism (cf
1005 : * set_rel_consider_parallel).
1006 : */
1007 2038 : splan->parallel_safe = false;
1008 2038 : splan->setParam = NIL;
1009 2038 : splan->parParam = NIL;
1010 2038 : splan->args = NIL;
1011 :
1012 : /*
1013 : * The node can't have any inputs (since it's an initplan), so the
1014 : * parParam and args lists remain empty. (It could contain references
1015 : * to earlier CTEs' output param IDs, but CTE outputs are not
1016 : * propagated via the args list.)
1017 : */
1018 :
1019 : /*
1020 : * Assign a param ID to represent the CTE's output. No ordinary
1021 : * "evaluation" of this param slot ever happens, but we use the param
1022 : * ID for setParam/chgParam signaling just as if the CTE plan were
1023 : * returning a simple scalar output. (Also, the executor abuses the
1024 : * ParamExecData slot for this param ID for communication among
1025 : * multiple CteScan nodes that might be scanning this CTE.)
1026 : */
1027 2038 : paramid = assign_special_exec_param(root);
1028 2038 : splan->setParam = list_make1_int(paramid);
1029 :
1030 : /*
1031 : * Add the subplan, its path, and its PlannerInfo to the global lists.
1032 : */
1033 2038 : root->glob->subplans = lappend(root->glob->subplans, plan);
1034 2038 : root->glob->subpaths = lappend(root->glob->subpaths, best_path);
1035 2038 : root->glob->subroots = lappend(root->glob->subroots, subroot);
1036 2038 : splan->plan_id = list_length(root->glob->subplans);
1037 :
1038 2038 : root->init_plans = lappend(root->init_plans, splan);
1039 :
1040 2038 : root->cte_plan_ids = lappend_int(root->cte_plan_ids, splan->plan_id);
1041 :
1042 : /* Label the subplan for EXPLAIN purposes */
1043 2038 : splan->plan_name = psprintf("CTE %s", cte->ctename);
1044 :
1045 : /* Lastly, fill in the cost estimates for use later */
1046 2038 : cost_subplan(root, splan, plan);
1047 : }
1048 2452 : }
1049 :
1050 : /*
1051 : * contain_dml: is any subquery not a plain SELECT?
1052 : *
1053 : * We reject SELECT FOR UPDATE/SHARE as well as INSERT etc.
1054 : */
1055 : static bool
1056 1438 : contain_dml(Node *node)
1057 : {
1058 1438 : return contain_dml_walker(node, NULL);
1059 : }
1060 :
1061 : static bool
1062 97572 : contain_dml_walker(Node *node, void *context)
1063 : {
1064 97572 : if (node == NULL)
1065 31368 : return false;
1066 66204 : if (IsA(node, Query))
1067 : {
1068 2446 : Query *query = (Query *) node;
1069 :
1070 2446 : if (query->commandType != CMD_SELECT ||
1071 2446 : query->rowMarks != NIL)
1072 8 : return true;
1073 :
1074 2438 : return query_tree_walker(query, contain_dml_walker, context, 0);
1075 : }
1076 63758 : return expression_tree_walker(node, contain_dml_walker, context);
1077 : }
1078 :
1079 : /*
1080 : * contain_outer_selfref: is there an external recursive self-reference?
1081 : */
1082 : static bool
1083 36 : contain_outer_selfref(Node *node)
1084 : {
1085 36 : Index depth = 0;
1086 :
1087 : /*
1088 : * We should be starting with a Query, so that depth will be 1 while
1089 : * examining its immediate contents.
1090 : */
1091 : Assert(IsA(node, Query));
1092 :
1093 36 : return contain_outer_selfref_walker(node, &depth);
1094 : }
1095 :
1096 : static bool
1097 810 : contain_outer_selfref_walker(Node *node, Index *depth)
1098 : {
1099 810 : if (node == NULL)
1100 486 : return false;
1101 324 : if (IsA(node, RangeTblEntry))
1102 : {
1103 30 : RangeTblEntry *rte = (RangeTblEntry *) node;
1104 :
1105 : /*
1106 : * Check for a self-reference to a CTE that's above the Query that our
1107 : * search started at.
1108 : */
1109 30 : if (rte->rtekind == RTE_CTE &&
1110 12 : rte->self_reference &&
1111 12 : rte->ctelevelsup >= *depth)
1112 12 : return true;
1113 18 : return false; /* allow range_table_walker to continue */
1114 : }
1115 294 : if (IsA(node, Query))
1116 : {
1117 : /* Recurse into subquery, tracking nesting depth properly */
1118 42 : Query *query = (Query *) node;
1119 : bool result;
1120 :
1121 42 : (*depth)++;
1122 :
1123 42 : result = query_tree_walker(query, contain_outer_selfref_walker,
1124 : (void *) depth, QTW_EXAMINE_RTES_BEFORE);
1125 :
1126 42 : (*depth)--;
1127 :
1128 42 : return result;
1129 : }
1130 252 : return expression_tree_walker(node, contain_outer_selfref_walker,
1131 : (void *) depth);
1132 : }
1133 :
1134 : /*
1135 : * inline_cte: convert RTE_CTE references to given CTE into RTE_SUBQUERYs
1136 : */
1137 : static void
1138 1352 : inline_cte(PlannerInfo *root, CommonTableExpr *cte)
1139 : {
1140 : struct inline_cte_walker_context context;
1141 :
1142 1352 : context.ctename = cte->ctename;
1143 : /* Start at levelsup = -1 because we'll immediately increment it */
1144 1352 : context.levelsup = -1;
1145 1352 : context.ctequery = castNode(Query, cte->ctequery);
1146 :
1147 1352 : (void) inline_cte_walker((Node *) root->parse, &context);
1148 1352 : }
1149 :
1150 : static bool
1151 485632 : inline_cte_walker(Node *node, inline_cte_walker_context *context)
1152 : {
1153 485632 : if (node == NULL)
1154 129702 : return false;
1155 355930 : if (IsA(node, Query))
1156 : {
1157 9502 : Query *query = (Query *) node;
1158 :
1159 9502 : context->levelsup++;
1160 :
1161 : /*
1162 : * Visit the query's RTE nodes after their contents; otherwise
1163 : * query_tree_walker would descend into the newly inlined CTE query,
1164 : * which we don't want.
1165 : */
1166 9502 : (void) query_tree_walker(query, inline_cte_walker, context,
1167 : QTW_EXAMINE_RTES_AFTER);
1168 :
1169 9502 : context->levelsup--;
1170 :
1171 9502 : return false;
1172 : }
1173 346428 : else if (IsA(node, RangeTblEntry))
1174 : {
1175 17806 : RangeTblEntry *rte = (RangeTblEntry *) node;
1176 :
1177 17806 : if (rte->rtekind == RTE_CTE &&
1178 5484 : strcmp(rte->ctename, context->ctename) == 0 &&
1179 1382 : rte->ctelevelsup == context->levelsup)
1180 : {
1181 : /*
1182 : * Found a reference to replace. Generate a copy of the CTE query
1183 : * with appropriate level adjustment for outer references (e.g.,
1184 : * to other CTEs).
1185 : */
1186 1376 : Query *newquery = copyObject(context->ctequery);
1187 :
1188 1376 : if (context->levelsup > 0)
1189 858 : IncrementVarSublevelsUp((Node *) newquery, context->levelsup, 1);
1190 :
1191 : /*
1192 : * Convert the RTE_CTE RTE into a RTE_SUBQUERY.
1193 : *
1194 : * Historically, a FOR UPDATE clause has been treated as extending
1195 : * into views and subqueries, but not into CTEs. We preserve this
1196 : * distinction by not trying to push rowmarks into the new
1197 : * subquery.
1198 : */
1199 1376 : rte->rtekind = RTE_SUBQUERY;
1200 1376 : rte->subquery = newquery;
1201 1376 : rte->security_barrier = false;
1202 :
1203 : /* Zero out CTE-specific fields */
1204 1376 : rte->ctename = NULL;
1205 1376 : rte->ctelevelsup = 0;
1206 1376 : rte->self_reference = false;
1207 1376 : rte->coltypes = NIL;
1208 1376 : rte->coltypmods = NIL;
1209 1376 : rte->colcollations = NIL;
1210 : }
1211 :
1212 17806 : return false;
1213 : }
1214 :
1215 328622 : return expression_tree_walker(node, inline_cte_walker, context);
1216 : }
1217 :
1218 :
1219 : /*
1220 : * convert_ANY_sublink_to_join: try to convert an ANY SubLink to a join
1221 : *
1222 : * The caller has found an ANY SubLink at the top level of one of the query's
1223 : * qual clauses, but has not checked the properties of the SubLink further.
1224 : * Decide whether it is appropriate to process this SubLink in join style.
1225 : * If so, form a JoinExpr and return it. Return NULL if the SubLink cannot
1226 : * be converted to a join.
1227 : *
1228 : * The only non-obvious input parameter is available_rels: this is the set
1229 : * of query rels that can safely be referenced in the sublink expression.
1230 : * (We must restrict this to avoid changing the semantics when a sublink
1231 : * is present in an outer join's ON qual.) The conversion must fail if
1232 : * the converted qual would reference any but these parent-query relids.
1233 : *
1234 : * On success, the returned JoinExpr has larg = NULL and rarg = the jointree
1235 : * item representing the pulled-up subquery. The caller must set larg to
1236 : * represent the relation(s) on the lefthand side of the new join, and insert
1237 : * the JoinExpr into the upper query's jointree at an appropriate place
1238 : * (typically, where the lefthand relation(s) had been). Note that the
1239 : * passed-in SubLink must also be removed from its original position in the
1240 : * query quals, since the quals of the returned JoinExpr replace it.
1241 : * (Notionally, we replace the SubLink with a constant TRUE, then elide the
1242 : * redundant constant from the qual.)
1243 : *
1244 : * On success, the caller is also responsible for recursively applying
1245 : * pull_up_sublinks processing to the rarg and quals of the returned JoinExpr.
1246 : * (On failure, there is no need to do anything, since pull_up_sublinks will
1247 : * be applied when we recursively plan the sub-select.)
1248 : *
1249 : * Side effects of a successful conversion include adding the SubLink's
1250 : * subselect to the query's rangetable, so that it can be referenced in
1251 : * the JoinExpr's rarg.
1252 : */
1253 : JoinExpr *
1254 1508 : convert_ANY_sublink_to_join(PlannerInfo *root, SubLink *sublink,
1255 : Relids available_rels)
1256 : {
1257 : JoinExpr *result;
1258 1508 : Query *parse = root->parse;
1259 1508 : Query *subselect = (Query *) sublink->subselect;
1260 : Relids upper_varnos;
1261 : int rtindex;
1262 : ParseNamespaceItem *nsitem;
1263 : RangeTblEntry *rte;
1264 : RangeTblRef *rtr;
1265 : List *subquery_vars;
1266 : Node *quals;
1267 : ParseState *pstate;
1268 : Relids sub_ref_outer_relids;
1269 : bool use_lateral;
1270 :
1271 : Assert(sublink->subLinkType == ANY_SUBLINK);
1272 :
1273 : /*
1274 : * If the sub-select contains any Vars of the parent query, we treat it as
1275 : * LATERAL. (Vars from higher levels don't matter here.)
1276 : */
1277 1508 : sub_ref_outer_relids = pull_varnos_of_level(NULL, (Node *) subselect, 1);
1278 1508 : use_lateral = !bms_is_empty(sub_ref_outer_relids);
1279 :
1280 : /*
1281 : * Can't convert if the sub-select contains parent-level Vars of relations
1282 : * not in available_rels.
1283 : */
1284 1508 : if (!bms_is_subset(sub_ref_outer_relids, available_rels))
1285 12 : return NULL;
1286 :
1287 : /*
1288 : * The test expression must contain some Vars of the parent query, else
1289 : * it's not gonna be a join. (Note that it won't have Vars referring to
1290 : * the subquery, rather Params.)
1291 : */
1292 1496 : upper_varnos = pull_varnos(root, sublink->testexpr);
1293 1496 : if (bms_is_empty(upper_varnos))
1294 12 : return NULL;
1295 :
1296 : /*
1297 : * However, it can't refer to anything outside available_rels.
1298 : */
1299 1484 : if (!bms_is_subset(upper_varnos, available_rels))
1300 12 : return NULL;
1301 :
1302 : /*
1303 : * The combining operators and left-hand expressions mustn't be volatile.
1304 : */
1305 1472 : if (contain_volatile_functions(sublink->testexpr))
1306 64 : return NULL;
1307 :
1308 : /* Create a dummy ParseState for addRangeTableEntryForSubquery */
1309 1408 : pstate = make_parsestate(NULL);
1310 :
1311 : /*
1312 : * Okay, pull up the sub-select into upper range table.
1313 : *
1314 : * We rely here on the assumption that the outer query has no references
1315 : * to the inner (necessarily true, other than the Vars that we build
1316 : * below). Therefore this is a lot easier than what pull_up_subqueries has
1317 : * to go through.
1318 : */
1319 1408 : nsitem = addRangeTableEntryForSubquery(pstate,
1320 : subselect,
1321 : makeAlias("ANY_subquery", NIL),
1322 : use_lateral,
1323 : false);
1324 1408 : rte = nsitem->p_rte;
1325 1408 : parse->rtable = lappend(parse->rtable, rte);
1326 1408 : rtindex = list_length(parse->rtable);
1327 :
1328 : /*
1329 : * Form a RangeTblRef for the pulled-up sub-select.
1330 : */
1331 1408 : rtr = makeNode(RangeTblRef);
1332 1408 : rtr->rtindex = rtindex;
1333 :
1334 : /*
1335 : * Build a list of Vars representing the subselect outputs.
1336 : */
1337 1408 : subquery_vars = generate_subquery_vars(root,
1338 : subselect->targetList,
1339 : rtindex);
1340 :
1341 : /*
1342 : * Build the new join's qual expression, replacing Params with these Vars.
1343 : */
1344 1408 : quals = convert_testexpr(root, sublink->testexpr, subquery_vars);
1345 :
1346 : /*
1347 : * And finally, build the JoinExpr node.
1348 : */
1349 1408 : result = makeNode(JoinExpr);
1350 1408 : result->jointype = JOIN_SEMI;
1351 1408 : result->isNatural = false;
1352 1408 : result->larg = NULL; /* caller must fill this in */
1353 1408 : result->rarg = (Node *) rtr;
1354 1408 : result->usingClause = NIL;
1355 1408 : result->join_using_alias = NULL;
1356 1408 : result->quals = quals;
1357 1408 : result->alias = NULL;
1358 1408 : result->rtindex = 0; /* we don't need an RTE for it */
1359 :
1360 1408 : return result;
1361 : }
1362 :
1363 : /*
1364 : * convert_EXISTS_sublink_to_join: try to convert an EXISTS SubLink to a join
1365 : *
1366 : * The API of this function is identical to convert_ANY_sublink_to_join's,
1367 : * except that we also support the case where the caller has found NOT EXISTS,
1368 : * so we need an additional input parameter "under_not".
1369 : */
1370 : JoinExpr *
1371 3232 : convert_EXISTS_sublink_to_join(PlannerInfo *root, SubLink *sublink,
1372 : bool under_not, Relids available_rels)
1373 : {
1374 : JoinExpr *result;
1375 3232 : Query *parse = root->parse;
1376 3232 : Query *subselect = (Query *) sublink->subselect;
1377 : Node *whereClause;
1378 : int rtoffset;
1379 : int varno;
1380 : Relids clause_varnos;
1381 : Relids upper_varnos;
1382 :
1383 : Assert(sublink->subLinkType == EXISTS_SUBLINK);
1384 :
1385 : /*
1386 : * Can't flatten if it contains WITH. (We could arrange to pull up the
1387 : * WITH into the parent query's cteList, but that risks changing the
1388 : * semantics, since a WITH ought to be executed once per associated query
1389 : * call.) Note that convert_ANY_sublink_to_join doesn't have to reject
1390 : * this case, since it just produces a subquery RTE that doesn't have to
1391 : * get flattened into the parent query.
1392 : */
1393 3232 : if (subselect->cteList)
1394 0 : return NULL;
1395 :
1396 : /*
1397 : * Copy the subquery so we can modify it safely (see comments in
1398 : * make_subplan).
1399 : */
1400 3232 : subselect = copyObject(subselect);
1401 :
1402 : /*
1403 : * See if the subquery can be simplified based on the knowledge that it's
1404 : * being used in EXISTS(). If we aren't able to get rid of its
1405 : * targetlist, we have to fail, because the pullup operation leaves us
1406 : * with noplace to evaluate the targetlist.
1407 : */
1408 3232 : if (!simplify_EXISTS_query(root, subselect))
1409 32 : return NULL;
1410 :
1411 : /*
1412 : * Separate out the WHERE clause. (We could theoretically also remove
1413 : * top-level plain JOIN/ON clauses, but it's probably not worth the
1414 : * trouble.)
1415 : */
1416 3200 : whereClause = subselect->jointree->quals;
1417 3200 : subselect->jointree->quals = NULL;
1418 :
1419 : /*
1420 : * The rest of the sub-select must not refer to any Vars of the parent
1421 : * query. (Vars of higher levels should be okay, though.)
1422 : */
1423 3200 : if (contain_vars_of_level((Node *) subselect, 1))
1424 0 : return NULL;
1425 :
1426 : /*
1427 : * On the other hand, the WHERE clause must contain some Vars of the
1428 : * parent query, else it's not gonna be a join.
1429 : */
1430 3200 : if (!contain_vars_of_level(whereClause, 1))
1431 62 : return NULL;
1432 :
1433 : /*
1434 : * We don't risk optimizing if the WHERE clause is volatile, either.
1435 : */
1436 3138 : if (contain_volatile_functions(whereClause))
1437 0 : return NULL;
1438 :
1439 : /*
1440 : * The subquery must have a nonempty jointree, but we can make it so.
1441 : */
1442 3138 : replace_empty_jointree(subselect);
1443 :
1444 : /*
1445 : * Prepare to pull up the sub-select into top range table.
1446 : *
1447 : * We rely here on the assumption that the outer query has no references
1448 : * to the inner (necessarily true). Therefore this is a lot easier than
1449 : * what pull_up_subqueries has to go through.
1450 : *
1451 : * In fact, it's even easier than what convert_ANY_sublink_to_join has to
1452 : * do. The machinations of simplify_EXISTS_query ensured that there is
1453 : * nothing interesting in the subquery except an rtable and jointree, and
1454 : * even the jointree FromExpr no longer has quals. So we can just append
1455 : * the rtable to our own and use the FromExpr in our jointree. But first,
1456 : * adjust all level-zero varnos in the subquery to account for the rtable
1457 : * merger.
1458 : */
1459 3138 : rtoffset = list_length(parse->rtable);
1460 3138 : OffsetVarNodes((Node *) subselect, rtoffset, 0);
1461 3138 : OffsetVarNodes(whereClause, rtoffset, 0);
1462 :
1463 : /*
1464 : * Upper-level vars in subquery will now be one level closer to their
1465 : * parent than before; in particular, anything that had been level 1
1466 : * becomes level zero.
1467 : */
1468 3138 : IncrementVarSublevelsUp((Node *) subselect, -1, 1);
1469 3138 : IncrementVarSublevelsUp(whereClause, -1, 1);
1470 :
1471 : /*
1472 : * Now that the WHERE clause is adjusted to match the parent query
1473 : * environment, we can easily identify all the level-zero rels it uses.
1474 : * The ones <= rtoffset belong to the upper query; the ones > rtoffset do
1475 : * not.
1476 : */
1477 3138 : clause_varnos = pull_varnos(root, whereClause);
1478 3138 : upper_varnos = NULL;
1479 3138 : varno = -1;
1480 9438 : while ((varno = bms_next_member(clause_varnos, varno)) >= 0)
1481 : {
1482 6300 : if (varno <= rtoffset)
1483 3162 : upper_varnos = bms_add_member(upper_varnos, varno);
1484 : }
1485 3138 : bms_free(clause_varnos);
1486 : Assert(!bms_is_empty(upper_varnos));
1487 :
1488 : /*
1489 : * Now that we've got the set of upper-level varnos, we can make the last
1490 : * check: only available_rels can be referenced.
1491 : */
1492 3138 : if (!bms_is_subset(upper_varnos, available_rels))
1493 32 : return NULL;
1494 :
1495 : /*
1496 : * Now we can attach the modified subquery rtable to the parent. This also
1497 : * adds subquery's RTEPermissionInfos into the upper query.
1498 : */
1499 3106 : CombineRangeTables(&parse->rtable, &parse->rteperminfos,
1500 : subselect->rtable, subselect->rteperminfos);
1501 :
1502 : /*
1503 : * And finally, build the JoinExpr node.
1504 : */
1505 3106 : result = makeNode(JoinExpr);
1506 3106 : result->jointype = under_not ? JOIN_ANTI : JOIN_SEMI;
1507 3106 : result->isNatural = false;
1508 3106 : result->larg = NULL; /* caller must fill this in */
1509 : /* flatten out the FromExpr node if it's useless */
1510 3106 : if (list_length(subselect->jointree->fromlist) == 1)
1511 3100 : result->rarg = (Node *) linitial(subselect->jointree->fromlist);
1512 : else
1513 6 : result->rarg = (Node *) subselect->jointree;
1514 3106 : result->usingClause = NIL;
1515 3106 : result->join_using_alias = NULL;
1516 3106 : result->quals = whereClause;
1517 3106 : result->alias = NULL;
1518 3106 : result->rtindex = 0; /* we don't need an RTE for it */
1519 :
1520 3106 : return result;
1521 : }
1522 :
1523 : /*
1524 : * simplify_EXISTS_query: remove any useless stuff in an EXISTS's subquery
1525 : *
1526 : * The only thing that matters about an EXISTS query is whether it returns
1527 : * zero or more than zero rows. Therefore, we can remove certain SQL features
1528 : * that won't affect that. The only part that is really likely to matter in
1529 : * typical usage is simplifying the targetlist: it's a common habit to write
1530 : * "SELECT * FROM" even though there is no need to evaluate any columns.
1531 : *
1532 : * Note: by suppressing the targetlist we could cause an observable behavioral
1533 : * change, namely that any errors that might occur in evaluating the tlist
1534 : * won't occur, nor will other side-effects of volatile functions. This seems
1535 : * unlikely to bother anyone in practice.
1536 : *
1537 : * Returns true if was able to discard the targetlist, else false.
1538 : */
1539 : static bool
1540 7144 : simplify_EXISTS_query(PlannerInfo *root, Query *query)
1541 : {
1542 : ListCell *lc;
1543 :
1544 : /*
1545 : * We don't try to simplify at all if the query uses set operations,
1546 : * aggregates, grouping sets, SRFs, modifying CTEs, HAVING, OFFSET, or FOR
1547 : * UPDATE/SHARE; none of these seem likely in normal usage and their
1548 : * possible effects are complex. (Note: we could ignore an "OFFSET 0"
1549 : * clause, but that traditionally is used as an optimization fence, so we
1550 : * don't.)
1551 : */
1552 7144 : if (query->commandType != CMD_SELECT ||
1553 7144 : query->setOperations ||
1554 7144 : query->hasAggs ||
1555 7144 : query->groupingSets ||
1556 7144 : query->hasWindowFuncs ||
1557 7144 : query->hasTargetSRFs ||
1558 7144 : query->hasModifyingCTE ||
1559 7144 : query->havingQual ||
1560 7144 : query->limitOffset ||
1561 7120 : query->rowMarks)
1562 52 : return false;
1563 :
1564 : /*
1565 : * LIMIT with a constant positive (or NULL) value doesn't affect the
1566 : * semantics of EXISTS, so let's ignore such clauses. This is worth doing
1567 : * because people accustomed to certain other DBMSes may be in the habit
1568 : * of writing EXISTS(SELECT ... LIMIT 1) as an optimization. If there's a
1569 : * LIMIT with anything else as argument, though, we can't simplify.
1570 : */
1571 7092 : if (query->limitCount)
1572 : {
1573 : /*
1574 : * The LIMIT clause has not yet been through eval_const_expressions,
1575 : * so we have to apply that here. It might seem like this is a waste
1576 : * of cycles, since the only case plausibly worth worrying about is
1577 : * "LIMIT 1" ... but what we'll actually see is "LIMIT int8(1::int4)",
1578 : * so we have to fold constants or we're not going to recognize it.
1579 : */
1580 24 : Node *node = eval_const_expressions(root, query->limitCount);
1581 : Const *limit;
1582 :
1583 : /* Might as well update the query if we simplified the clause. */
1584 24 : query->limitCount = node;
1585 :
1586 24 : if (!IsA(node, Const))
1587 0 : return false;
1588 :
1589 24 : limit = (Const *) node;
1590 : Assert(limit->consttype == INT8OID);
1591 24 : if (!limit->constisnull && DatumGetInt64(limit->constvalue) <= 0)
1592 12 : return false;
1593 :
1594 : /* Whether or not the targetlist is safe, we can drop the LIMIT. */
1595 12 : query->limitCount = NULL;
1596 : }
1597 :
1598 : /*
1599 : * Otherwise, we can throw away the targetlist, as well as any GROUP,
1600 : * WINDOW, DISTINCT, and ORDER BY clauses; none of those clauses will
1601 : * change a nonzero-rows result to zero rows or vice versa. (Furthermore,
1602 : * since our parsetree representation of these clauses depends on the
1603 : * targetlist, we'd better throw them away if we drop the targetlist.)
1604 : */
1605 7080 : query->targetList = NIL;
1606 7080 : query->groupClause = NIL;
1607 7080 : query->windowClause = NIL;
1608 7080 : query->distinctClause = NIL;
1609 7080 : query->sortClause = NIL;
1610 7080 : query->hasDistinctOn = false;
1611 :
1612 : /*
1613 : * Since we have thrown away the GROUP BY clauses, we'd better remove the
1614 : * RTE_GROUP RTE and clear the hasGroupRTE flag.
1615 : */
1616 14364 : foreach(lc, query->rtable)
1617 : {
1618 7290 : RangeTblEntry *rte = lfirst_node(RangeTblEntry, lc);
1619 :
1620 : /*
1621 : * Remove the RTE_GROUP RTE and clear the hasGroupRTE flag. (Since
1622 : * we'll exit the foreach loop immediately, we don't bother with
1623 : * foreach_delete_current.)
1624 : */
1625 7290 : if (rte->rtekind == RTE_GROUP)
1626 : {
1627 : Assert(query->hasGroupRTE);
1628 6 : query->rtable = list_delete_cell(query->rtable, lc);
1629 6 : query->hasGroupRTE = false;
1630 6 : break;
1631 : }
1632 : }
1633 :
1634 7080 : return true;
1635 : }
1636 :
1637 : /*
1638 : * convert_EXISTS_to_ANY: try to convert EXISTS to a hashable ANY sublink
1639 : *
1640 : * The subselect is expected to be a fresh copy that we can munge up,
1641 : * and to have been successfully passed through simplify_EXISTS_query.
1642 : *
1643 : * On success, the modified subselect is returned, and we store a suitable
1644 : * upper-level test expression at *testexpr, plus a list of the subselect's
1645 : * output Params at *paramIds. (The test expression is already Param-ified
1646 : * and hence need not go through convert_testexpr, which is why we have to
1647 : * deal with the Param IDs specially.)
1648 : *
1649 : * On failure, returns NULL.
1650 : */
1651 : static Query *
1652 1814 : convert_EXISTS_to_ANY(PlannerInfo *root, Query *subselect,
1653 : Node **testexpr, List **paramIds)
1654 : {
1655 : Node *whereClause;
1656 : List *leftargs,
1657 : *rightargs,
1658 : *opids,
1659 : *opcollations,
1660 : *newWhere,
1661 : *tlist,
1662 : *testlist,
1663 : *paramids;
1664 : ListCell *lc,
1665 : *rc,
1666 : *oc,
1667 : *cc;
1668 : AttrNumber resno;
1669 :
1670 : /*
1671 : * Query must not require a targetlist, since we have to insert a new one.
1672 : * Caller should have dealt with the case already.
1673 : */
1674 : Assert(subselect->targetList == NIL);
1675 :
1676 : /*
1677 : * Separate out the WHERE clause. (We could theoretically also remove
1678 : * top-level plain JOIN/ON clauses, but it's probably not worth the
1679 : * trouble.)
1680 : */
1681 1814 : whereClause = subselect->jointree->quals;
1682 1814 : subselect->jointree->quals = NULL;
1683 :
1684 : /*
1685 : * The rest of the sub-select must not refer to any Vars of the parent
1686 : * query. (Vars of higher levels should be okay, though.)
1687 : *
1688 : * Note: we need not check for Aggrefs separately because we know the
1689 : * sub-select is as yet unoptimized; any uplevel Aggref must therefore
1690 : * contain an uplevel Var reference. This is not the case below ...
1691 : */
1692 1814 : if (contain_vars_of_level((Node *) subselect, 1))
1693 6 : return NULL;
1694 :
1695 : /*
1696 : * We don't risk optimizing if the WHERE clause is volatile, either.
1697 : */
1698 1808 : if (contain_volatile_functions(whereClause))
1699 0 : return NULL;
1700 :
1701 : /*
1702 : * Clean up the WHERE clause by doing const-simplification etc on it.
1703 : * Aside from simplifying the processing we're about to do, this is
1704 : * important for being able to pull chunks of the WHERE clause up into the
1705 : * parent query. Since we are invoked partway through the parent's
1706 : * preprocess_expression() work, earlier steps of preprocess_expression()
1707 : * wouldn't get applied to the pulled-up stuff unless we do them here. For
1708 : * the parts of the WHERE clause that get put back into the child query,
1709 : * this work is partially duplicative, but it shouldn't hurt.
1710 : *
1711 : * Note: we do not run flatten_join_alias_vars. This is OK because any
1712 : * parent aliases were flattened already, and we're not going to pull any
1713 : * child Vars (of any description) into the parent.
1714 : *
1715 : * Note: passing the parent's root to eval_const_expressions is
1716 : * technically wrong, but we can get away with it since only the
1717 : * boundParams (if any) are used, and those would be the same in a
1718 : * subroot.
1719 : */
1720 1808 : whereClause = eval_const_expressions(root, whereClause);
1721 1808 : whereClause = (Node *) canonicalize_qual((Expr *) whereClause, false);
1722 1808 : whereClause = (Node *) make_ands_implicit((Expr *) whereClause);
1723 :
1724 : /*
1725 : * We now have a flattened implicit-AND list of clauses, which we try to
1726 : * break apart into "outervar = innervar" hash clauses. Anything that
1727 : * can't be broken apart just goes back into the newWhere list. Note that
1728 : * we aren't trying hard yet to ensure that we have only outer or only
1729 : * inner on each side; we'll check that if we get to the end.
1730 : */
1731 1808 : leftargs = rightargs = opids = opcollations = newWhere = NIL;
1732 6902 : foreach(lc, (List *) whereClause)
1733 : {
1734 5094 : OpExpr *expr = (OpExpr *) lfirst(lc);
1735 :
1736 8328 : if (IsA(expr, OpExpr) &&
1737 3234 : hash_ok_operator(expr))
1738 : {
1739 2612 : Node *leftarg = (Node *) linitial(expr->args);
1740 2612 : Node *rightarg = (Node *) lsecond(expr->args);
1741 :
1742 2612 : if (contain_vars_of_level(leftarg, 1))
1743 : {
1744 338 : leftargs = lappend(leftargs, leftarg);
1745 338 : rightargs = lappend(rightargs, rightarg);
1746 338 : opids = lappend_oid(opids, expr->opno);
1747 338 : opcollations = lappend_oid(opcollations, expr->inputcollid);
1748 338 : continue;
1749 : }
1750 2274 : if (contain_vars_of_level(rightarg, 1))
1751 : {
1752 : /*
1753 : * We must commute the clause to put the outer var on the
1754 : * left, because the hashing code in nodeSubplan.c expects
1755 : * that. This probably shouldn't ever fail, since hashable
1756 : * operators ought to have commutators, but be paranoid.
1757 : */
1758 1938 : expr->opno = get_commutator(expr->opno);
1759 1938 : if (OidIsValid(expr->opno) && hash_ok_operator(expr))
1760 : {
1761 1938 : leftargs = lappend(leftargs, rightarg);
1762 1938 : rightargs = lappend(rightargs, leftarg);
1763 1938 : opids = lappend_oid(opids, expr->opno);
1764 1938 : opcollations = lappend_oid(opcollations, expr->inputcollid);
1765 1938 : continue;
1766 : }
1767 : /* If no commutator, no chance to optimize the WHERE clause */
1768 0 : return NULL;
1769 : }
1770 : }
1771 : /* Couldn't handle it as a hash clause */
1772 2818 : newWhere = lappend(newWhere, expr);
1773 : }
1774 :
1775 : /*
1776 : * If we didn't find anything we could convert, fail.
1777 : */
1778 1808 : if (leftargs == NIL)
1779 308 : return NULL;
1780 :
1781 : /*
1782 : * There mustn't be any parent Vars or Aggs in the stuff that we intend to
1783 : * put back into the child query. Note: you might think we don't need to
1784 : * check for Aggs separately, because an uplevel Agg must contain an
1785 : * uplevel Var in its argument. But it is possible that the uplevel Var
1786 : * got optimized away by eval_const_expressions. Consider
1787 : *
1788 : * SUM(CASE WHEN false THEN uplevelvar ELSE 0 END)
1789 : */
1790 3000 : if (contain_vars_of_level((Node *) newWhere, 1) ||
1791 1500 : contain_vars_of_level((Node *) rightargs, 1))
1792 0 : return NULL;
1793 1542 : if (root->parse->hasAggs &&
1794 84 : (contain_aggs_of_level((Node *) newWhere, 1) ||
1795 42 : contain_aggs_of_level((Node *) rightargs, 1)))
1796 0 : return NULL;
1797 :
1798 : /*
1799 : * And there can't be any child Vars in the stuff we intend to pull up.
1800 : * (Note: we'd need to check for child Aggs too, except we know the child
1801 : * has no aggs at all because of simplify_EXISTS_query's check. The same
1802 : * goes for window functions.)
1803 : */
1804 1500 : if (contain_vars_of_level((Node *) leftargs, 0))
1805 0 : return NULL;
1806 :
1807 : /*
1808 : * Also reject sublinks in the stuff we intend to pull up. (It might be
1809 : * possible to support this, but doesn't seem worth the complication.)
1810 : */
1811 1500 : if (contain_subplans((Node *) leftargs))
1812 0 : return NULL;
1813 :
1814 : /*
1815 : * Okay, adjust the sublevelsup in the stuff we're pulling up.
1816 : */
1817 1500 : IncrementVarSublevelsUp((Node *) leftargs, -1, 1);
1818 :
1819 : /*
1820 : * Put back any child-level-only WHERE clauses.
1821 : */
1822 1500 : if (newWhere)
1823 1308 : subselect->jointree->quals = (Node *) make_ands_explicit(newWhere);
1824 :
1825 : /*
1826 : * Build a new targetlist for the child that emits the expressions we
1827 : * need. Concurrently, build a testexpr for the parent using Params to
1828 : * reference the child outputs. (Since we generate Params directly here,
1829 : * there will be no need to convert the testexpr in build_subplan.)
1830 : */
1831 1500 : tlist = testlist = paramids = NIL;
1832 1500 : resno = 1;
1833 3776 : forfour(lc, leftargs, rc, rightargs, oc, opids, cc, opcollations)
1834 : {
1835 2276 : Node *leftarg = (Node *) lfirst(lc);
1836 2276 : Node *rightarg = (Node *) lfirst(rc);
1837 2276 : Oid opid = lfirst_oid(oc);
1838 2276 : Oid opcollation = lfirst_oid(cc);
1839 : Param *param;
1840 :
1841 2276 : param = generate_new_exec_param(root,
1842 : exprType(rightarg),
1843 : exprTypmod(rightarg),
1844 : exprCollation(rightarg));
1845 2276 : tlist = lappend(tlist,
1846 2276 : makeTargetEntry((Expr *) rightarg,
1847 2276 : resno++,
1848 : NULL,
1849 : false));
1850 2276 : testlist = lappend(testlist,
1851 2276 : make_opclause(opid, BOOLOID, false,
1852 : (Expr *) leftarg, (Expr *) param,
1853 : InvalidOid, opcollation));
1854 2276 : paramids = lappend_int(paramids, param->paramid);
1855 : }
1856 :
1857 : /* Put everything where it should go, and we're done */
1858 1500 : subselect->targetList = tlist;
1859 1500 : *testexpr = (Node *) make_ands_explicit(testlist);
1860 1500 : *paramIds = paramids;
1861 :
1862 1500 : return subselect;
1863 : }
1864 :
1865 :
1866 : /*
1867 : * Replace correlation vars (uplevel vars) with Params.
1868 : *
1869 : * Uplevel PlaceHolderVars, aggregates, GROUPING() expressions, and
1870 : * MergeSupportFuncs are replaced, too.
1871 : *
1872 : * Note: it is critical that this runs immediately after SS_process_sublinks.
1873 : * Since we do not recurse into the arguments of uplevel PHVs and aggregates,
1874 : * they will get copied to the appropriate subplan args list in the parent
1875 : * query with uplevel vars not replaced by Params, but only adjusted in level
1876 : * (see replace_outer_placeholdervar and replace_outer_agg). That's exactly
1877 : * what we want for the vars of the parent level --- but if a PHV's or
1878 : * aggregate's argument contains any further-up variables, they have to be
1879 : * replaced with Params in their turn. That will happen when the parent level
1880 : * runs SS_replace_correlation_vars. Therefore it must do so after expanding
1881 : * its sublinks to subplans. And we don't want any steps in between, else
1882 : * those steps would never get applied to the argument expressions, either in
1883 : * the parent or the child level.
1884 : *
1885 : * Another fairly tricky thing going on here is the handling of SubLinks in
1886 : * the arguments of uplevel PHVs/aggregates. Those are not touched inside the
1887 : * intermediate query level, either. Instead, SS_process_sublinks recurses on
1888 : * them after copying the PHV or Aggref expression into the parent plan level
1889 : * (this is actually taken care of in build_subplan).
1890 : */
1891 : Node *
1892 135930 : SS_replace_correlation_vars(PlannerInfo *root, Node *expr)
1893 : {
1894 : /* No setup needed for tree walk, so away we go */
1895 135930 : return replace_correlation_vars_mutator(expr, root);
1896 : }
1897 :
1898 : static Node *
1899 1142692 : replace_correlation_vars_mutator(Node *node, PlannerInfo *root)
1900 : {
1901 1142692 : if (node == NULL)
1902 50644 : return NULL;
1903 1092048 : if (IsA(node, Var))
1904 : {
1905 297626 : if (((Var *) node)->varlevelsup > 0)
1906 48032 : return (Node *) replace_outer_var(root, (Var *) node);
1907 : }
1908 1044016 : if (IsA(node, PlaceHolderVar))
1909 : {
1910 84 : if (((PlaceHolderVar *) node)->phlevelsup > 0)
1911 42 : return (Node *) replace_outer_placeholdervar(root,
1912 : (PlaceHolderVar *) node);
1913 : }
1914 1043974 : if (IsA(node, Aggref))
1915 : {
1916 7368 : if (((Aggref *) node)->agglevelsup > 0)
1917 52 : return (Node *) replace_outer_agg(root, (Aggref *) node);
1918 : }
1919 1043922 : if (IsA(node, GroupingFunc))
1920 : {
1921 90 : if (((GroupingFunc *) node)->agglevelsup > 0)
1922 64 : return (Node *) replace_outer_grouping(root, (GroupingFunc *) node);
1923 : }
1924 1043858 : if (IsA(node, MergeSupportFunc))
1925 : {
1926 24 : if (root->parse->commandType != CMD_MERGE)
1927 6 : return (Node *) replace_outer_merge_support(root,
1928 : (MergeSupportFunc *) node);
1929 : }
1930 1043852 : return expression_tree_mutator(node,
1931 : replace_correlation_vars_mutator,
1932 : (void *) root);
1933 : }
1934 :
1935 : /*
1936 : * Expand SubLinks to SubPlans in the given expression.
1937 : *
1938 : * The isQual argument tells whether or not this expression is a WHERE/HAVING
1939 : * qualifier expression. If it is, any sublinks appearing at top level need
1940 : * not distinguish FALSE from UNKNOWN return values.
1941 : */
1942 : Node *
1943 84068 : SS_process_sublinks(PlannerInfo *root, Node *expr, bool isQual)
1944 : {
1945 : process_sublinks_context context;
1946 :
1947 84068 : context.root = root;
1948 84068 : context.isTopQual = isQual;
1949 84068 : return process_sublinks_mutator(expr, &context);
1950 : }
1951 :
1952 : static Node *
1953 1129192 : process_sublinks_mutator(Node *node, process_sublinks_context *context)
1954 : {
1955 : process_sublinks_context locContext;
1956 :
1957 1129192 : locContext.root = context->root;
1958 :
1959 1129192 : if (node == NULL)
1960 52052 : return NULL;
1961 1077140 : if (IsA(node, SubLink))
1962 : {
1963 34672 : SubLink *sublink = (SubLink *) node;
1964 : Node *testexpr;
1965 :
1966 : /*
1967 : * First, recursively process the lefthand-side expressions, if any.
1968 : * They're not top-level anymore.
1969 : */
1970 34672 : locContext.isTopQual = false;
1971 34672 : testexpr = process_sublinks_mutator(sublink->testexpr, &locContext);
1972 :
1973 : /*
1974 : * Now build the SubPlan node and make the expr to return.
1975 : */
1976 34672 : return make_subplan(context->root,
1977 34672 : (Query *) sublink->subselect,
1978 : sublink->subLinkType,
1979 : sublink->subLinkId,
1980 : testexpr,
1981 34672 : context->isTopQual);
1982 : }
1983 :
1984 : /*
1985 : * Don't recurse into the arguments of an outer PHV, Aggref or
1986 : * GroupingFunc here. Any SubLinks in the arguments have to be dealt with
1987 : * at the outer query level; they'll be handled when build_subplan
1988 : * collects the PHV, Aggref or GroupingFunc into the arguments to be
1989 : * passed down to the current subplan.
1990 : */
1991 1042468 : if (IsA(node, PlaceHolderVar))
1992 : {
1993 162 : if (((PlaceHolderVar *) node)->phlevelsup > 0)
1994 0 : return node;
1995 : }
1996 1042306 : else if (IsA(node, Aggref))
1997 : {
1998 566 : if (((Aggref *) node)->agglevelsup > 0)
1999 18 : return node;
2000 : }
2001 1041740 : else if (IsA(node, GroupingFunc))
2002 : {
2003 160 : if (((GroupingFunc *) node)->agglevelsup > 0)
2004 36 : return node;
2005 : }
2006 :
2007 : /*
2008 : * We should never see a SubPlan expression in the input (since this is
2009 : * the very routine that creates 'em to begin with). We shouldn't find
2010 : * ourselves invoked directly on a Query, either.
2011 : */
2012 : Assert(!IsA(node, SubPlan));
2013 : Assert(!IsA(node, AlternativeSubPlan));
2014 : Assert(!IsA(node, Query));
2015 :
2016 : /*
2017 : * Because make_subplan() could return an AND or OR clause, we have to
2018 : * take steps to preserve AND/OR flatness of a qual. We assume the input
2019 : * has been AND/OR flattened and so we need no recursion here.
2020 : *
2021 : * (Due to the coding here, we will not get called on the List subnodes of
2022 : * an AND; and the input is *not* yet in implicit-AND format. So no check
2023 : * is needed for a bare List.)
2024 : *
2025 : * Anywhere within the top-level AND/OR clause structure, we can tell
2026 : * make_subplan() that NULL and FALSE are interchangeable. So isTopQual
2027 : * propagates down in both cases. (Note that this is unlike the meaning
2028 : * of "top level qual" used in most other places in Postgres.)
2029 : */
2030 1042414 : if (is_andclause(node))
2031 : {
2032 14544 : List *newargs = NIL;
2033 : ListCell *l;
2034 :
2035 : /* Still at qual top-level */
2036 14544 : locContext.isTopQual = context->isTopQual;
2037 :
2038 54390 : foreach(l, ((BoolExpr *) node)->args)
2039 : {
2040 : Node *newarg;
2041 :
2042 39846 : newarg = process_sublinks_mutator(lfirst(l), &locContext);
2043 39846 : if (is_andclause(newarg))
2044 0 : newargs = list_concat(newargs, ((BoolExpr *) newarg)->args);
2045 : else
2046 39846 : newargs = lappend(newargs, newarg);
2047 : }
2048 14544 : return (Node *) make_andclause(newargs);
2049 : }
2050 :
2051 1027870 : if (is_orclause(node))
2052 : {
2053 1968 : List *newargs = NIL;
2054 : ListCell *l;
2055 :
2056 : /* Still at qual top-level */
2057 1968 : locContext.isTopQual = context->isTopQual;
2058 :
2059 6922 : foreach(l, ((BoolExpr *) node)->args)
2060 : {
2061 : Node *newarg;
2062 :
2063 4954 : newarg = process_sublinks_mutator(lfirst(l), &locContext);
2064 4954 : if (is_orclause(newarg))
2065 0 : newargs = list_concat(newargs, ((BoolExpr *) newarg)->args);
2066 : else
2067 4954 : newargs = lappend(newargs, newarg);
2068 : }
2069 1968 : return (Node *) make_orclause(newargs);
2070 : }
2071 :
2072 : /*
2073 : * If we recurse down through anything other than an AND or OR node, we
2074 : * are definitely not at top qual level anymore.
2075 : */
2076 1025902 : locContext.isTopQual = false;
2077 :
2078 1025902 : return expression_tree_mutator(node,
2079 : process_sublinks_mutator,
2080 : (void *) &locContext);
2081 : }
2082 :
2083 : /*
2084 : * SS_identify_outer_params - identify the Params available from outer levels
2085 : *
2086 : * This must be run after SS_replace_correlation_vars and SS_process_sublinks
2087 : * processing is complete in a given query level as well as all of its
2088 : * descendant levels (which means it's most practical to do it at the end of
2089 : * processing the query level). We compute the set of paramIds that outer
2090 : * levels will make available to this level+descendants, and record it in
2091 : * root->outer_params for use while computing extParam/allParam sets in final
2092 : * plan cleanup. (We can't just compute it then, because the upper levels'
2093 : * plan_params lists are transient and will be gone by then.)
2094 : */
2095 : void
2096 512086 : SS_identify_outer_params(PlannerInfo *root)
2097 : {
2098 : Bitmapset *outer_params;
2099 : PlannerInfo *proot;
2100 : ListCell *l;
2101 :
2102 : /*
2103 : * If no parameters have been assigned anywhere in the tree, we certainly
2104 : * don't need to do anything here.
2105 : */
2106 512086 : if (root->glob->paramExecTypes == NIL)
2107 348294 : return;
2108 :
2109 : /*
2110 : * Scan all query levels above this one to see which parameters are due to
2111 : * be available from them, either because lower query levels have
2112 : * requested them (via plan_params) or because they will be available from
2113 : * initPlans of those levels.
2114 : */
2115 163792 : outer_params = NULL;
2116 212624 : for (proot = root->parent_root; proot != NULL; proot = proot->parent_root)
2117 : {
2118 : /* Include ordinary Var/PHV/Aggref/GroupingFunc params */
2119 90226 : foreach(l, proot->plan_params)
2120 : {
2121 41394 : PlannerParamItem *pitem = (PlannerParamItem *) lfirst(l);
2122 :
2123 41394 : outer_params = bms_add_member(outer_params, pitem->paramId);
2124 : }
2125 : /* Include any outputs of outer-level initPlans */
2126 53830 : foreach(l, proot->init_plans)
2127 : {
2128 4998 : SubPlan *initsubplan = (SubPlan *) lfirst(l);
2129 : ListCell *l2;
2130 :
2131 9996 : foreach(l2, initsubplan->setParam)
2132 : {
2133 4998 : outer_params = bms_add_member(outer_params, lfirst_int(l2));
2134 : }
2135 : }
2136 : /* Include worktable ID, if a recursive query is being planned */
2137 48832 : if (proot->wt_param_id >= 0)
2138 2372 : outer_params = bms_add_member(outer_params, proot->wt_param_id);
2139 : }
2140 163792 : root->outer_params = outer_params;
2141 : }
2142 :
2143 : /*
2144 : * SS_charge_for_initplans - account for initplans in Path costs & parallelism
2145 : *
2146 : * If any initPlans have been created in the current query level, they will
2147 : * get attached to the Plan tree created from whichever Path we select from
2148 : * the given rel. Increment all that rel's Paths' costs to account for them,
2149 : * and if any of the initPlans are parallel-unsafe, mark all the rel's Paths
2150 : * parallel-unsafe as well.
2151 : *
2152 : * This is separate from SS_attach_initplans because we might conditionally
2153 : * create more initPlans during create_plan(), depending on which Path we
2154 : * select. However, Paths that would generate such initPlans are expected
2155 : * to have included their cost and parallel-safety effects already.
2156 : */
2157 : void
2158 512086 : SS_charge_for_initplans(PlannerInfo *root, RelOptInfo *final_rel)
2159 : {
2160 : Cost initplan_cost;
2161 : bool unsafe_initplans;
2162 : ListCell *lc;
2163 :
2164 : /* Nothing to do if no initPlans */
2165 512086 : if (root->init_plans == NIL)
2166 502124 : return;
2167 :
2168 : /*
2169 : * Compute the cost increment just once, since it will be the same for all
2170 : * Paths. Also check for parallel-unsafe initPlans.
2171 : */
2172 9962 : SS_compute_initplan_cost(root->init_plans,
2173 : &initplan_cost, &unsafe_initplans);
2174 :
2175 : /*
2176 : * Now adjust the costs and parallel_safe flags.
2177 : */
2178 20050 : foreach(lc, final_rel->pathlist)
2179 : {
2180 10088 : Path *path = (Path *) lfirst(lc);
2181 :
2182 10088 : path->startup_cost += initplan_cost;
2183 10088 : path->total_cost += initplan_cost;
2184 10088 : if (unsafe_initplans)
2185 5868 : path->parallel_safe = false;
2186 : }
2187 :
2188 : /*
2189 : * Adjust partial paths' costs too, or forget them entirely if we must
2190 : * consider the rel parallel-unsafe.
2191 : */
2192 9962 : if (unsafe_initplans)
2193 : {
2194 5830 : final_rel->partial_pathlist = NIL;
2195 5830 : final_rel->consider_parallel = false;
2196 : }
2197 : else
2198 : {
2199 4144 : foreach(lc, final_rel->partial_pathlist)
2200 : {
2201 12 : Path *path = (Path *) lfirst(lc);
2202 :
2203 12 : path->startup_cost += initplan_cost;
2204 12 : path->total_cost += initplan_cost;
2205 : }
2206 : }
2207 :
2208 : /* We needn't do set_cheapest() here, caller will do it */
2209 : }
2210 :
2211 : /*
2212 : * SS_compute_initplan_cost - count up the cost delta for some initplans
2213 : *
2214 : * The total cost returned in *initplan_cost_p should be added to both the
2215 : * startup and total costs of the plan node the initplans get attached to.
2216 : * We also report whether any of the initplans are not parallel-safe.
2217 : *
2218 : * The primary user of this is SS_charge_for_initplans, but it's also
2219 : * used in adjusting costs when we move initplans to another plan node.
2220 : */
2221 : void
2222 10154 : SS_compute_initplan_cost(List *init_plans,
2223 : Cost *initplan_cost_p,
2224 : bool *unsafe_initplans_p)
2225 : {
2226 : Cost initplan_cost;
2227 : bool unsafe_initplans;
2228 : ListCell *lc;
2229 :
2230 : /*
2231 : * We assume each initPlan gets run once during top plan startup. This is
2232 : * a conservative overestimate, since in fact an initPlan might be
2233 : * executed later than plan startup, or even not at all.
2234 : */
2235 10154 : initplan_cost = 0;
2236 10154 : unsafe_initplans = false;
2237 21242 : foreach(lc, init_plans)
2238 : {
2239 11088 : SubPlan *initsubplan = lfirst_node(SubPlan, lc);
2240 :
2241 11088 : initplan_cost += initsubplan->startup_cost + initsubplan->per_call_cost;
2242 11088 : if (!initsubplan->parallel_safe)
2243 6720 : unsafe_initplans = true;
2244 : }
2245 10154 : *initplan_cost_p = initplan_cost;
2246 10154 : *unsafe_initplans_p = unsafe_initplans;
2247 10154 : }
2248 :
2249 : /*
2250 : * SS_attach_initplans - attach initplans to topmost plan node
2251 : *
2252 : * Attach any initplans created in the current query level to the specified
2253 : * plan node, which should normally be the topmost node for the query level.
2254 : * (In principle the initPlans could go in any node at or above where they're
2255 : * referenced; but there seems no reason to put them any lower than the
2256 : * topmost node, so we don't bother to track exactly where they came from.)
2257 : *
2258 : * We do not touch the plan node's cost or parallel_safe flag. The initplans
2259 : * must have been accounted for in SS_charge_for_initplans, or by any later
2260 : * code that adds initplans via SS_make_initplan_from_plan.
2261 : */
2262 : void
2263 510828 : SS_attach_initplans(PlannerInfo *root, Plan *plan)
2264 : {
2265 510828 : plan->initPlan = root->init_plans;
2266 510828 : }
2267 :
2268 : /*
2269 : * SS_finalize_plan - do final parameter processing for a completed Plan.
2270 : *
2271 : * This recursively computes the extParam and allParam sets for every Plan
2272 : * node in the given plan tree. (Oh, and RangeTblFunction.funcparams too.)
2273 : *
2274 : * We assume that SS_finalize_plan has already been run on any initplans or
2275 : * subplans the plan tree could reference.
2276 : */
2277 : void
2278 189094 : SS_finalize_plan(PlannerInfo *root, Plan *plan)
2279 : {
2280 : /* No setup needed, just recurse through plan tree. */
2281 189094 : (void) finalize_plan(root, plan, -1, root->outer_params, NULL);
2282 189094 : }
2283 :
2284 : /*
2285 : * Recursive processing of all nodes in the plan tree
2286 : *
2287 : * gather_param is the rescan_param of an ancestral Gather/GatherMerge,
2288 : * or -1 if there is none.
2289 : *
2290 : * valid_params is the set of param IDs supplied by outer plan levels
2291 : * that are valid to reference in this plan node or its children.
2292 : *
2293 : * scan_params is a set of param IDs to force scan plan nodes to reference.
2294 : * This is for EvalPlanQual support, and is always NULL at the top of the
2295 : * recursion.
2296 : *
2297 : * The return value is the computed allParam set for the given Plan node.
2298 : * This is just an internal notational convenience: we can add a child
2299 : * plan's allParams to the set of param IDs of interest to this level
2300 : * in the same statement that recurses to that child.
2301 : *
2302 : * Do not scribble on caller's values of valid_params or scan_params!
2303 : *
2304 : * Note: although we attempt to deal with initPlans anywhere in the tree, the
2305 : * logic is not really right. The problem is that a plan node might return an
2306 : * output Param of its initPlan as a targetlist item, in which case it's valid
2307 : * for the parent plan level to reference that same Param; the parent's usage
2308 : * will be converted into a Var referencing the child plan node by setrefs.c.
2309 : * But this function would see the parent's reference as out of scope and
2310 : * complain about it. For now, this does not matter because the planner only
2311 : * attaches initPlans to the topmost plan node in a query level, so the case
2312 : * doesn't arise. If we ever merge this processing into setrefs.c, maybe it
2313 : * can be handled more cleanly.
2314 : */
2315 : static Bitmapset *
2316 1394274 : finalize_plan(PlannerInfo *root, Plan *plan,
2317 : int gather_param,
2318 : Bitmapset *valid_params,
2319 : Bitmapset *scan_params)
2320 : {
2321 : finalize_primnode_context context;
2322 : int locally_added_param;
2323 : Bitmapset *nestloop_params;
2324 : Bitmapset *initExtParam;
2325 : Bitmapset *initSetParam;
2326 : Bitmapset *child_params;
2327 : ListCell *l;
2328 :
2329 1394274 : if (plan == NULL)
2330 812122 : return NULL;
2331 :
2332 582152 : context.root = root;
2333 582152 : context.paramids = NULL; /* initialize set to empty */
2334 582152 : locally_added_param = -1; /* there isn't one */
2335 582152 : nestloop_params = NULL; /* there aren't any */
2336 :
2337 : /*
2338 : * Examine any initPlans to determine the set of external params they
2339 : * reference and the set of output params they supply. (We assume
2340 : * SS_finalize_plan was run on them already.)
2341 : */
2342 582152 : initExtParam = initSetParam = NULL;
2343 593580 : foreach(l, plan->initPlan)
2344 : {
2345 11428 : SubPlan *initsubplan = (SubPlan *) lfirst(l);
2346 11428 : Plan *initplan = planner_subplan_get_plan(root, initsubplan);
2347 : ListCell *l2;
2348 :
2349 11428 : initExtParam = bms_add_members(initExtParam, initplan->extParam);
2350 22904 : foreach(l2, initsubplan->setParam)
2351 : {
2352 11476 : initSetParam = bms_add_member(initSetParam, lfirst_int(l2));
2353 : }
2354 : }
2355 :
2356 : /* Any setParams are validly referenceable in this node and children */
2357 582152 : if (initSetParam)
2358 10314 : valid_params = bms_union(valid_params, initSetParam);
2359 :
2360 : /*
2361 : * When we call finalize_primnode, context.paramids sets are automatically
2362 : * merged together. But when recursing to self, we have to do it the hard
2363 : * way. We want the paramids set to include params in subplans as well as
2364 : * at this level.
2365 : */
2366 :
2367 : /* Find params in targetlist and qual */
2368 582152 : finalize_primnode((Node *) plan->targetlist, &context);
2369 582152 : finalize_primnode((Node *) plan->qual, &context);
2370 :
2371 : /*
2372 : * If it's a parallel-aware scan node, mark it as dependent on the parent
2373 : * Gather/GatherMerge's rescan Param.
2374 : */
2375 582152 : if (plan->parallel_aware)
2376 : {
2377 2496 : if (gather_param < 0)
2378 0 : elog(ERROR, "parallel-aware plan node is not below a Gather");
2379 2496 : context.paramids =
2380 2496 : bms_add_member(context.paramids, gather_param);
2381 : }
2382 :
2383 : /* Check additional node-type-specific fields */
2384 582152 : switch (nodeTag(plan))
2385 : {
2386 74964 : case T_Result:
2387 74964 : finalize_primnode(((Result *) plan)->resconstantqual,
2388 : &context);
2389 74964 : break;
2390 :
2391 82306 : case T_SeqScan:
2392 82306 : context.paramids = bms_add_members(context.paramids, scan_params);
2393 82306 : break;
2394 :
2395 98 : case T_SampleScan:
2396 98 : finalize_primnode((Node *) ((SampleScan *) plan)->tablesample,
2397 : &context);
2398 98 : context.paramids = bms_add_members(context.paramids, scan_params);
2399 98 : break;
2400 :
2401 89704 : case T_IndexScan:
2402 89704 : finalize_primnode((Node *) ((IndexScan *) plan)->indexqual,
2403 : &context);
2404 89704 : finalize_primnode((Node *) ((IndexScan *) plan)->indexorderby,
2405 : &context);
2406 :
2407 : /*
2408 : * we need not look at indexqualorig, since it will have the same
2409 : * param references as indexqual. Likewise, we can ignore
2410 : * indexorderbyorig.
2411 : */
2412 89704 : context.paramids = bms_add_members(context.paramids, scan_params);
2413 89704 : break;
2414 :
2415 6644 : case T_IndexOnlyScan:
2416 6644 : finalize_primnode((Node *) ((IndexOnlyScan *) plan)->indexqual,
2417 : &context);
2418 6644 : finalize_primnode((Node *) ((IndexOnlyScan *) plan)->recheckqual,
2419 : &context);
2420 6644 : finalize_primnode((Node *) ((IndexOnlyScan *) plan)->indexorderby,
2421 : &context);
2422 :
2423 : /*
2424 : * we need not look at indextlist, since it cannot contain Params.
2425 : */
2426 6644 : context.paramids = bms_add_members(context.paramids, scan_params);
2427 6644 : break;
2428 :
2429 8072 : case T_BitmapIndexScan:
2430 8072 : finalize_primnode((Node *) ((BitmapIndexScan *) plan)->indexqual,
2431 : &context);
2432 :
2433 : /*
2434 : * we need not look at indexqualorig, since it will have the same
2435 : * param references as indexqual.
2436 : */
2437 8072 : break;
2438 :
2439 7862 : case T_BitmapHeapScan:
2440 7862 : finalize_primnode((Node *) ((BitmapHeapScan *) plan)->bitmapqualorig,
2441 : &context);
2442 7862 : context.paramids = bms_add_members(context.paramids, scan_params);
2443 7862 : break;
2444 :
2445 576 : case T_TidScan:
2446 576 : finalize_primnode((Node *) ((TidScan *) plan)->tidquals,
2447 : &context);
2448 576 : context.paramids = bms_add_members(context.paramids, scan_params);
2449 576 : break;
2450 :
2451 34 : case T_TidRangeScan:
2452 34 : finalize_primnode((Node *) ((TidRangeScan *) plan)->tidrangequals,
2453 : &context);
2454 34 : context.paramids = bms_add_members(context.paramids, scan_params);
2455 34 : break;
2456 :
2457 16784 : case T_SubqueryScan:
2458 : {
2459 16784 : SubqueryScan *sscan = (SubqueryScan *) plan;
2460 : RelOptInfo *rel;
2461 : Bitmapset *subquery_params;
2462 :
2463 : /* We must run finalize_plan on the subquery */
2464 16784 : rel = find_base_rel(root, sscan->scan.scanrelid);
2465 16784 : subquery_params = rel->subroot->outer_params;
2466 16784 : if (gather_param >= 0)
2467 24 : subquery_params = bms_add_member(bms_copy(subquery_params),
2468 : gather_param);
2469 16784 : finalize_plan(rel->subroot, sscan->subplan, gather_param,
2470 : subquery_params, NULL);
2471 :
2472 : /* Now we can add its extParams to the parent's params */
2473 33568 : context.paramids = bms_add_members(context.paramids,
2474 16784 : sscan->subplan->extParam);
2475 : /* We need scan_params too, though */
2476 16784 : context.paramids = bms_add_members(context.paramids,
2477 : scan_params);
2478 : }
2479 16784 : break;
2480 :
2481 22424 : case T_FunctionScan:
2482 : {
2483 22424 : FunctionScan *fscan = (FunctionScan *) plan;
2484 : ListCell *lc;
2485 :
2486 : /*
2487 : * Call finalize_primnode independently on each function
2488 : * expression, so that we can record which params are
2489 : * referenced in each, in order to decide which need
2490 : * re-evaluating during rescan.
2491 : */
2492 44872 : foreach(lc, fscan->functions)
2493 : {
2494 22448 : RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc);
2495 : finalize_primnode_context funccontext;
2496 :
2497 22448 : funccontext = context;
2498 22448 : funccontext.paramids = NULL;
2499 :
2500 22448 : finalize_primnode(rtfunc->funcexpr, &funccontext);
2501 :
2502 : /* remember results for execution */
2503 22448 : rtfunc->funcparams = funccontext.paramids;
2504 :
2505 : /* add the function's params to the overall set */
2506 22448 : context.paramids = bms_add_members(context.paramids,
2507 22448 : funccontext.paramids);
2508 : }
2509 :
2510 22424 : context.paramids = bms_add_members(context.paramids,
2511 : scan_params);
2512 : }
2513 22424 : break;
2514 :
2515 234 : case T_TableFuncScan:
2516 234 : finalize_primnode((Node *) ((TableFuncScan *) plan)->tablefunc,
2517 : &context);
2518 234 : context.paramids = bms_add_members(context.paramids, scan_params);
2519 234 : break;
2520 :
2521 5370 : case T_ValuesScan:
2522 5370 : finalize_primnode((Node *) ((ValuesScan *) plan)->values_lists,
2523 : &context);
2524 5370 : context.paramids = bms_add_members(context.paramids, scan_params);
2525 5370 : break;
2526 :
2527 3188 : case T_CteScan:
2528 : {
2529 : /*
2530 : * You might think we should add the node's cteParam to
2531 : * paramids, but we shouldn't because that param is just a
2532 : * linkage mechanism for multiple CteScan nodes for the same
2533 : * CTE; it is never used for changed-param signaling. What we
2534 : * have to do instead is to find the referenced CTE plan and
2535 : * incorporate its external paramids, so that the correct
2536 : * things will happen if the CTE references outer-level
2537 : * variables. See test cases for bug #4902. (We assume
2538 : * SS_finalize_plan was run on the CTE plan already.)
2539 : */
2540 3188 : int plan_id = ((CteScan *) plan)->ctePlanId;
2541 : Plan *cteplan;
2542 :
2543 : /* so, do this ... */
2544 3188 : if (plan_id < 1 || plan_id > list_length(root->glob->subplans))
2545 0 : elog(ERROR, "could not find plan for CteScan referencing plan ID %d",
2546 : plan_id);
2547 3188 : cteplan = (Plan *) list_nth(root->glob->subplans, plan_id - 1);
2548 3188 : context.paramids =
2549 3188 : bms_add_members(context.paramids, cteplan->extParam);
2550 :
2551 : #ifdef NOT_USED
2552 : /* ... but not this */
2553 : context.paramids =
2554 : bms_add_member(context.paramids,
2555 : ((CteScan *) plan)->cteParam);
2556 : #endif
2557 :
2558 3188 : context.paramids = bms_add_members(context.paramids,
2559 : scan_params);
2560 : }
2561 3188 : break;
2562 :
2563 806 : case T_WorkTableScan:
2564 806 : context.paramids =
2565 806 : bms_add_member(context.paramids,
2566 : ((WorkTableScan *) plan)->wtParam);
2567 806 : context.paramids = bms_add_members(context.paramids, scan_params);
2568 806 : break;
2569 :
2570 374 : case T_NamedTuplestoreScan:
2571 374 : context.paramids = bms_add_members(context.paramids, scan_params);
2572 374 : break;
2573 :
2574 764 : case T_ForeignScan:
2575 : {
2576 764 : ForeignScan *fscan = (ForeignScan *) plan;
2577 :
2578 764 : finalize_primnode((Node *) fscan->fdw_exprs,
2579 : &context);
2580 764 : finalize_primnode((Node *) fscan->fdw_recheck_quals,
2581 : &context);
2582 :
2583 : /* We assume fdw_scan_tlist cannot contain Params */
2584 764 : context.paramids = bms_add_members(context.paramids,
2585 : scan_params);
2586 : }
2587 764 : break;
2588 :
2589 0 : case T_CustomScan:
2590 : {
2591 0 : CustomScan *cscan = (CustomScan *) plan;
2592 : ListCell *lc;
2593 :
2594 0 : finalize_primnode((Node *) cscan->custom_exprs,
2595 : &context);
2596 : /* We assume custom_scan_tlist cannot contain Params */
2597 0 : context.paramids =
2598 0 : bms_add_members(context.paramids, scan_params);
2599 :
2600 : /* child nodes if any */
2601 0 : foreach(lc, cscan->custom_plans)
2602 : {
2603 0 : context.paramids =
2604 0 : bms_add_members(context.paramids,
2605 0 : finalize_plan(root,
2606 0 : (Plan *) lfirst(lc),
2607 : gather_param,
2608 : valid_params,
2609 : scan_params));
2610 : }
2611 : }
2612 0 : break;
2613 :
2614 89932 : case T_ModifyTable:
2615 : {
2616 89932 : ModifyTable *mtplan = (ModifyTable *) plan;
2617 :
2618 : /* Force descendant scan nodes to reference epqParam */
2619 89932 : locally_added_param = mtplan->epqParam;
2620 89932 : valid_params = bms_add_member(bms_copy(valid_params),
2621 : locally_added_param);
2622 89932 : scan_params = bms_add_member(bms_copy(scan_params),
2623 : locally_added_param);
2624 89932 : finalize_primnode((Node *) mtplan->returningLists,
2625 : &context);
2626 89932 : finalize_primnode((Node *) mtplan->onConflictSet,
2627 : &context);
2628 89932 : finalize_primnode((Node *) mtplan->onConflictWhere,
2629 : &context);
2630 : /* exclRelTlist contains only Vars, doesn't need examination */
2631 : }
2632 89932 : break;
2633 :
2634 9472 : case T_Append:
2635 : {
2636 32796 : foreach(l, ((Append *) plan)->appendplans)
2637 : {
2638 23324 : context.paramids =
2639 23324 : bms_add_members(context.paramids,
2640 23324 : finalize_plan(root,
2641 23324 : (Plan *) lfirst(l),
2642 : gather_param,
2643 : valid_params,
2644 : scan_params));
2645 : }
2646 : }
2647 9472 : break;
2648 :
2649 108 : case T_MergeAppend:
2650 : {
2651 456 : foreach(l, ((MergeAppend *) plan)->mergeplans)
2652 : {
2653 348 : context.paramids =
2654 348 : bms_add_members(context.paramids,
2655 348 : finalize_plan(root,
2656 348 : (Plan *) lfirst(l),
2657 : gather_param,
2658 : valid_params,
2659 : scan_params));
2660 : }
2661 : }
2662 108 : break;
2663 :
2664 86 : case T_BitmapAnd:
2665 : {
2666 258 : foreach(l, ((BitmapAnd *) plan)->bitmapplans)
2667 : {
2668 172 : context.paramids =
2669 172 : bms_add_members(context.paramids,
2670 172 : finalize_plan(root,
2671 172 : (Plan *) lfirst(l),
2672 : gather_param,
2673 : valid_params,
2674 : scan_params));
2675 : }
2676 : }
2677 86 : break;
2678 :
2679 124 : case T_BitmapOr:
2680 : {
2681 372 : foreach(l, ((BitmapOr *) plan)->bitmapplans)
2682 : {
2683 248 : context.paramids =
2684 248 : bms_add_members(context.paramids,
2685 248 : finalize_plan(root,
2686 248 : (Plan *) lfirst(l),
2687 : gather_param,
2688 : valid_params,
2689 : scan_params));
2690 : }
2691 : }
2692 124 : break;
2693 :
2694 61186 : case T_NestLoop:
2695 : {
2696 61186 : finalize_primnode((Node *) ((Join *) plan)->joinqual,
2697 : &context);
2698 : /* collect set of params that will be passed to right child */
2699 107440 : foreach(l, ((NestLoop *) plan)->nestParams)
2700 : {
2701 46254 : NestLoopParam *nlp = (NestLoopParam *) lfirst(l);
2702 :
2703 46254 : nestloop_params = bms_add_member(nestloop_params,
2704 : nlp->paramno);
2705 : }
2706 : }
2707 61186 : break;
2708 :
2709 3882 : case T_MergeJoin:
2710 3882 : finalize_primnode((Node *) ((Join *) plan)->joinqual,
2711 : &context);
2712 3882 : finalize_primnode((Node *) ((MergeJoin *) plan)->mergeclauses,
2713 : &context);
2714 3882 : break;
2715 :
2716 16608 : case T_HashJoin:
2717 16608 : finalize_primnode((Node *) ((Join *) plan)->joinqual,
2718 : &context);
2719 16608 : finalize_primnode((Node *) ((HashJoin *) plan)->hashclauses,
2720 : &context);
2721 16608 : break;
2722 :
2723 16608 : case T_Hash:
2724 16608 : finalize_primnode((Node *) ((Hash *) plan)->hashkeys,
2725 : &context);
2726 16608 : break;
2727 :
2728 2156 : case T_Limit:
2729 2156 : finalize_primnode(((Limit *) plan)->limitOffset,
2730 : &context);
2731 2156 : finalize_primnode(((Limit *) plan)->limitCount,
2732 : &context);
2733 2156 : break;
2734 :
2735 806 : case T_RecursiveUnion:
2736 : /* child nodes are allowed to reference wtParam */
2737 806 : locally_added_param = ((RecursiveUnion *) plan)->wtParam;
2738 806 : valid_params = bms_add_member(bms_copy(valid_params),
2739 : locally_added_param);
2740 : /* wtParam does *not* get added to scan_params */
2741 806 : break;
2742 :
2743 7708 : case T_LockRows:
2744 : /* Force descendant scan nodes to reference epqParam */
2745 7708 : locally_added_param = ((LockRows *) plan)->epqParam;
2746 7708 : valid_params = bms_add_member(bms_copy(valid_params),
2747 : locally_added_param);
2748 7708 : scan_params = bms_add_member(bms_copy(scan_params),
2749 : locally_added_param);
2750 7708 : break;
2751 :
2752 9214 : case T_Agg:
2753 : {
2754 9214 : Agg *agg = (Agg *) plan;
2755 :
2756 : /*
2757 : * AGG_HASHED plans need to know which Params are referenced
2758 : * in aggregate calls. Do a separate scan to identify them.
2759 : */
2760 9214 : if (agg->aggstrategy == AGG_HASHED)
2761 : {
2762 : finalize_primnode_context aggcontext;
2763 :
2764 1212 : aggcontext.root = root;
2765 1212 : aggcontext.paramids = NULL;
2766 1212 : finalize_agg_primnode((Node *) agg->plan.targetlist,
2767 : &aggcontext);
2768 1212 : finalize_agg_primnode((Node *) agg->plan.qual,
2769 : &aggcontext);
2770 1212 : agg->aggParams = aggcontext.paramids;
2771 : }
2772 : }
2773 9214 : break;
2774 :
2775 116 : case T_WindowAgg:
2776 116 : finalize_primnode(((WindowAgg *) plan)->startOffset,
2777 : &context);
2778 116 : finalize_primnode(((WindowAgg *) plan)->endOffset,
2779 : &context);
2780 116 : break;
2781 :
2782 936 : case T_Gather:
2783 : /* child nodes are allowed to reference rescan_param, if any */
2784 936 : locally_added_param = ((Gather *) plan)->rescan_param;
2785 936 : if (locally_added_param >= 0)
2786 : {
2787 936 : valid_params = bms_add_member(bms_copy(valid_params),
2788 : locally_added_param);
2789 :
2790 : /*
2791 : * We currently don't support nested Gathers. The issue so
2792 : * far as this function is concerned would be how to identify
2793 : * which child nodes depend on which Gather.
2794 : */
2795 : Assert(gather_param < 0);
2796 : /* Pass down rescan_param to child parallel-aware nodes */
2797 936 : gather_param = locally_added_param;
2798 : }
2799 : /* rescan_param does *not* get added to scan_params */
2800 936 : break;
2801 :
2802 318 : case T_GatherMerge:
2803 : /* child nodes are allowed to reference rescan_param, if any */
2804 318 : locally_added_param = ((GatherMerge *) plan)->rescan_param;
2805 318 : if (locally_added_param >= 0)
2806 : {
2807 318 : valid_params = bms_add_member(bms_copy(valid_params),
2808 : locally_added_param);
2809 :
2810 : /*
2811 : * We currently don't support nested Gathers. The issue so
2812 : * far as this function is concerned would be how to identify
2813 : * which child nodes depend on which Gather.
2814 : */
2815 : Assert(gather_param < 0);
2816 : /* Pass down rescan_param to child parallel-aware nodes */
2817 318 : gather_param = locally_added_param;
2818 : }
2819 : /* rescan_param does *not* get added to scan_params */
2820 318 : break;
2821 :
2822 1362 : case T_Memoize:
2823 1362 : finalize_primnode((Node *) ((Memoize *) plan)->param_exprs,
2824 : &context);
2825 1362 : break;
2826 :
2827 41326 : case T_ProjectSet:
2828 : case T_Material:
2829 : case T_Sort:
2830 : case T_IncrementalSort:
2831 : case T_Unique:
2832 : case T_SetOp:
2833 : case T_Group:
2834 : /* no node-type-specific fields need fixing */
2835 41326 : break;
2836 :
2837 0 : default:
2838 0 : elog(ERROR, "unrecognized node type: %d",
2839 : (int) nodeTag(plan));
2840 : }
2841 :
2842 : /* Process left and right child plans, if any */
2843 582152 : child_params = finalize_plan(root,
2844 582152 : plan->lefttree,
2845 : gather_param,
2846 : valid_params,
2847 : scan_params);
2848 582152 : context.paramids = bms_add_members(context.paramids, child_params);
2849 :
2850 582152 : if (nestloop_params)
2851 : {
2852 : /* right child can reference nestloop_params as well as valid_params */
2853 42270 : child_params = finalize_plan(root,
2854 42270 : plan->righttree,
2855 : gather_param,
2856 : bms_union(nestloop_params, valid_params),
2857 : scan_params);
2858 : /* ... and they don't count as parameters used at my level */
2859 42270 : child_params = bms_difference(child_params, nestloop_params);
2860 42270 : bms_free(nestloop_params);
2861 : }
2862 : else
2863 : {
2864 : /* easy case */
2865 539882 : child_params = finalize_plan(root,
2866 539882 : plan->righttree,
2867 : gather_param,
2868 : valid_params,
2869 : scan_params);
2870 : }
2871 582152 : context.paramids = bms_add_members(context.paramids, child_params);
2872 :
2873 : /*
2874 : * Any locally generated parameter doesn't count towards its generating
2875 : * plan node's external dependencies. (Note: if we changed valid_params
2876 : * and/or scan_params, we leak those bitmapsets; not worth the notational
2877 : * trouble to clean them up.)
2878 : */
2879 582152 : if (locally_added_param >= 0)
2880 : {
2881 99700 : context.paramids = bms_del_member(context.paramids,
2882 : locally_added_param);
2883 : }
2884 :
2885 : /* Now we have all the paramids referenced in this node and children */
2886 :
2887 582152 : if (!bms_is_subset(context.paramids, valid_params))
2888 0 : elog(ERROR, "plan should not reference subplan's variable");
2889 :
2890 : /*
2891 : * The plan node's allParam and extParam fields should include all its
2892 : * referenced paramids, plus contributions from any child initPlans.
2893 : * However, any setParams of the initPlans should not be present in the
2894 : * parent node's extParams, only in its allParams. (It's possible that
2895 : * some initPlans have extParams that are setParams of other initPlans.)
2896 : */
2897 :
2898 : /* allParam must include initplans' extParams and setParams */
2899 582152 : plan->allParam = bms_union(context.paramids, initExtParam);
2900 582152 : plan->allParam = bms_add_members(plan->allParam, initSetParam);
2901 : /* extParam must include any initplan extParams */
2902 582152 : plan->extParam = bms_union(context.paramids, initExtParam);
2903 : /* but not any initplan setParams */
2904 582152 : plan->extParam = bms_del_members(plan->extParam, initSetParam);
2905 :
2906 582152 : return plan->allParam;
2907 : }
2908 :
2909 : /*
2910 : * finalize_primnode: add IDs of all PARAM_EXEC params that appear (or will
2911 : * appear) in the given expression tree to the result set.
2912 : */
2913 : static bool
2914 9419160 : finalize_primnode(Node *node, finalize_primnode_context *context)
2915 : {
2916 9419160 : if (node == NULL)
2917 1189898 : return false;
2918 8229262 : if (IsA(node, Param))
2919 : {
2920 117348 : if (((Param *) node)->paramkind == PARAM_EXEC)
2921 : {
2922 114036 : int paramid = ((Param *) node)->paramid;
2923 :
2924 114036 : context->paramids = bms_add_member(context->paramids, paramid);
2925 : }
2926 117348 : return false; /* no more to do here */
2927 : }
2928 8111914 : else if (IsA(node, Aggref))
2929 : {
2930 : /*
2931 : * Check to see if the aggregate will be replaced by a Param
2932 : * referencing a subquery output during setrefs.c. If so, we must
2933 : * account for that Param here. (For various reasons, it's not
2934 : * convenient to perform that substitution earlier than setrefs.c, nor
2935 : * to perform this processing after setrefs.c. Thus we need a wart
2936 : * here.)
2937 : */
2938 12556 : Aggref *aggref = (Aggref *) node;
2939 : Param *aggparam;
2940 :
2941 12556 : aggparam = find_minmax_agg_replacement_param(context->root, aggref);
2942 12556 : if (aggparam != NULL)
2943 556 : context->paramids = bms_add_member(context->paramids,
2944 : aggparam->paramid);
2945 : /* Fall through to examine the agg's arguments */
2946 : }
2947 8099358 : else if (IsA(node, SubPlan))
2948 : {
2949 33224 : SubPlan *subplan = (SubPlan *) node;
2950 33224 : Plan *plan = planner_subplan_get_plan(context->root, subplan);
2951 : ListCell *lc;
2952 : Bitmapset *subparamids;
2953 :
2954 : /* Recurse into the testexpr, but not into the Plan */
2955 33224 : finalize_primnode(subplan->testexpr, context);
2956 :
2957 : /*
2958 : * Remove any param IDs of output parameters of the subplan that were
2959 : * referenced in the testexpr. These are not interesting for
2960 : * parameter change signaling since we always re-evaluate the subplan.
2961 : * Note that this wouldn't work too well if there might be uses of the
2962 : * same param IDs elsewhere in the plan, but that can't happen because
2963 : * generate_new_exec_param never tries to merge params.
2964 : */
2965 36146 : foreach(lc, subplan->paramIds)
2966 : {
2967 2922 : context->paramids = bms_del_member(context->paramids,
2968 : lfirst_int(lc));
2969 : }
2970 :
2971 : /* Also examine args list */
2972 33224 : finalize_primnode((Node *) subplan->args, context);
2973 :
2974 : /*
2975 : * Add params needed by the subplan to paramids, but excluding those
2976 : * we will pass down to it. (We assume SS_finalize_plan was run on
2977 : * the subplan already.)
2978 : */
2979 33224 : subparamids = bms_copy(plan->extParam);
2980 80756 : foreach(lc, subplan->parParam)
2981 : {
2982 47532 : subparamids = bms_del_member(subparamids, lfirst_int(lc));
2983 : }
2984 33224 : context->paramids = bms_join(context->paramids, subparamids);
2985 :
2986 33224 : return false; /* no more to do here */
2987 : }
2988 8078690 : return expression_tree_walker(node, finalize_primnode,
2989 : (void *) context);
2990 : }
2991 :
2992 : /*
2993 : * finalize_agg_primnode: find all Aggref nodes in the given expression tree,
2994 : * and add IDs of all PARAM_EXEC params appearing within their aggregated
2995 : * arguments to the result set.
2996 : */
2997 : static bool
2998 10074 : finalize_agg_primnode(Node *node, finalize_primnode_context *context)
2999 : {
3000 10074 : if (node == NULL)
3001 1288 : return false;
3002 8786 : if (IsA(node, Aggref))
3003 : {
3004 1132 : Aggref *agg = (Aggref *) node;
3005 :
3006 : /* we should not consider the direct arguments, if any */
3007 1132 : finalize_primnode((Node *) agg->args, context);
3008 1132 : finalize_primnode((Node *) agg->aggfilter, context);
3009 1132 : return false; /* there can't be any Aggrefs below here */
3010 : }
3011 7654 : return expression_tree_walker(node, finalize_agg_primnode,
3012 : (void *) context);
3013 : }
3014 :
3015 : /*
3016 : * SS_make_initplan_output_param - make a Param for an initPlan's output
3017 : *
3018 : * The plan is expected to return a scalar value of the given type/collation.
3019 : *
3020 : * Note that in some cases the initplan may not ever appear in the finished
3021 : * plan tree. If that happens, we'll have wasted a PARAM_EXEC slot, which
3022 : * is no big deal.
3023 : */
3024 : Param *
3025 446 : SS_make_initplan_output_param(PlannerInfo *root,
3026 : Oid resulttype, int32 resulttypmod,
3027 : Oid resultcollation)
3028 : {
3029 446 : return generate_new_exec_param(root, resulttype,
3030 : resulttypmod, resultcollation);
3031 : }
3032 :
3033 : /*
3034 : * SS_make_initplan_from_plan - given a plan tree, make it an InitPlan
3035 : *
3036 : * We build an EXPR_SUBLINK SubPlan node and put it into the initplan
3037 : * list for the outer query level. A Param that represents the initplan's
3038 : * output has already been assigned using SS_make_initplan_output_param.
3039 : */
3040 : void
3041 400 : SS_make_initplan_from_plan(PlannerInfo *root,
3042 : PlannerInfo *subroot, Plan *plan,
3043 : Param *prm)
3044 : {
3045 : SubPlan *node;
3046 :
3047 : /*
3048 : * Add the subplan and its PlannerInfo, as well as a dummy path entry, to
3049 : * the global lists. Ideally we'd save a real path, but right now our
3050 : * sole caller doesn't build a path that exactly matches the plan. Since
3051 : * we're not currently going to need the path for an initplan, it's not
3052 : * worth requiring construction of such a path.
3053 : */
3054 400 : root->glob->subplans = lappend(root->glob->subplans, plan);
3055 400 : root->glob->subpaths = lappend(root->glob->subpaths, NULL);
3056 400 : root->glob->subroots = lappend(root->glob->subroots, subroot);
3057 :
3058 : /*
3059 : * Create a SubPlan node and add it to the outer list of InitPlans. Note
3060 : * it has to appear after any other InitPlans it might depend on (see
3061 : * comments in ExecReScan).
3062 : */
3063 400 : node = makeNode(SubPlan);
3064 400 : node->subLinkType = EXPR_SUBLINK;
3065 400 : node->plan_id = list_length(root->glob->subplans);
3066 400 : node->plan_name = psprintf("InitPlan %d", node->plan_id);
3067 400 : get_first_col_type(plan, &node->firstColType, &node->firstColTypmod,
3068 : &node->firstColCollation);
3069 400 : node->parallel_safe = plan->parallel_safe;
3070 400 : node->setParam = list_make1_int(prm->paramid);
3071 :
3072 400 : root->init_plans = lappend(root->init_plans, node);
3073 :
3074 : /*
3075 : * The node can't have any inputs (since it's an initplan), so the
3076 : * parParam and args lists remain empty.
3077 : */
3078 :
3079 : /* Set costs of SubPlan using info from the plan tree */
3080 400 : cost_subplan(subroot, node, plan);
3081 400 : }
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