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 36050 : 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 36050 : if (plan->targetlist)
123 : {
124 33772 : TargetEntry *tent = linitial_node(TargetEntry, plan->targetlist);
125 :
126 33772 : if (!tent->resjunk)
127 : {
128 33772 : *coltype = exprType((Node *) tent->expr);
129 33772 : *coltypmod = exprTypmod((Node *) tent->expr);
130 33772 : *colcollation = exprCollation((Node *) tent->expr);
131 33772 : return;
132 : }
133 : }
134 2278 : *coltype = VOIDOID;
135 2278 : *coltypmod = -1;
136 2278 : *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 32150 : make_subplan(PlannerInfo *root, Query *orig_subquery,
163 : SubLinkType subLinkType, int subLinkId,
164 : Node *testexpr, bool isTopQual)
165 : {
166 : Query *subquery;
167 32150 : 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 32150 : subquery = copyObject(orig_subquery);
183 :
184 : /*
185 : * If it's an EXISTS subplan, we might be able to simplify it.
186 : */
187 32150 : if (subLinkType == EXISTS_SUBLINK)
188 2040 : 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 32150 : if (subLinkType == EXISTS_SUBLINK)
210 2040 : tuple_fraction = 1.0; /* just like a LIMIT 1 */
211 30110 : else if (subLinkType == ALL_SUBLINK ||
212 : subLinkType == ANY_SUBLINK)
213 492 : tuple_fraction = 0.5; /* 50% */
214 : else
215 29618 : 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 32150 : subroot = subquery_planner(root->glob, subquery, root, false,
222 : tuple_fraction, NULL);
223 :
224 : /* Isolate the params needed by this specific subplan */
225 32150 : plan_params = root->plan_params;
226 32150 : 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 32150 : final_rel = fetch_upper_rel(subroot, UPPERREL_FINAL, NULL);
233 32150 : best_path = get_cheapest_fractional_path(final_rel, tuple_fraction);
234 :
235 32150 : plan = create_plan(subroot, best_path);
236 :
237 : /* And convert to SubPlan or InitPlan format. */
238 32150 : 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 32150 : 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 1494 : subroot = subquery_planner(root->glob, subquery, root, false, 0.0,
269 : NULL);
270 :
271 : /* Isolate the params needed by this specific subplan */
272 1494 : plan_params = root->plan_params;
273 1494 : root->plan_params = NIL;
274 :
275 : /* Select best Path */
276 1494 : final_rel = fetch_upper_rel(subroot, UPPERREL_FINAL, NULL);
277 1494 : best_path = final_rel->cheapest_total_path;
278 :
279 : /* Now we can check if it'll fit in hash_mem */
280 1494 : if (subpath_is_hashable(best_path))
281 : {
282 : SubPlan *hashplan;
283 : AlternativeSubPlan *asplan;
284 :
285 : /* OK, finish planning the ANY subquery */
286 1494 : plan = create_plan(subroot, best_path);
287 :
288 : /* ... and convert to SubPlan format */
289 1494 : 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 1494 : asplan = makeNode(AlternativeSubPlan);
302 1494 : asplan->subplans = list_make2(result, hashplan);
303 1494 : result = (Node *) asplan;
304 1494 : root->hasAlternativeSubPlans = true;
305 : }
306 : }
307 : }
308 :
309 32150 : 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 33644 : 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 33644 : splan = makeNode(SubPlan);
335 33644 : splan->subLinkType = subLinkType;
336 33644 : splan->testexpr = NULL;
337 33644 : splan->paramIds = NIL;
338 33644 : get_first_col_type(plan, &splan->firstColType, &splan->firstColTypmod,
339 : &splan->firstColCollation);
340 33644 : splan->useHashTable = false;
341 33644 : splan->unknownEqFalse = unknownEqFalse;
342 33644 : splan->parallel_safe = plan->parallel_safe;
343 33644 : splan->setParam = NIL;
344 33644 : splan->parParam = NIL;
345 33644 : 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 71140 : foreach(lc, plan_params)
352 : {
353 37496 : PlannerParamItem *pitem = (PlannerParamItem *) lfirst(lc);
354 37496 : 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 37496 : if (IsA(arg, PlaceHolderVar) ||
366 37484 : IsA(arg, Aggref) ||
367 37432 : IsA(arg, GroupingFunc))
368 128 : arg = SS_process_sublinks(root, arg, false);
369 :
370 37496 : splan->parParam = lappend_int(splan->parParam, pitem->paramId);
371 37496 : 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 33644 : if (splan->parParam == NIL && subLinkType == EXISTS_SUBLINK)
386 194 : {
387 : Param *prm;
388 :
389 : Assert(testexpr == NULL);
390 194 : prm = generate_new_exec_param(root, BOOLOID, -1, InvalidOid);
391 194 : splan->setParam = list_make1_int(prm->paramid);
392 194 : isInitPlan = true;
393 194 : result = (Node *) prm;
394 : }
395 33450 : else if (splan->parParam == NIL && subLinkType == EXPR_SUBLINK)
396 8356 : {
397 8356 : TargetEntry *te = linitial(plan->targetlist);
398 : Param *prm;
399 :
400 : Assert(!te->resjunk);
401 : Assert(testexpr == NULL);
402 8356 : prm = generate_new_exec_param(root,
403 8356 : exprType((Node *) te->expr),
404 8356 : exprTypmod((Node *) te->expr),
405 8356 : exprCollation((Node *) te->expr));
406 8356 : splan->setParam = list_make1_int(prm->paramid);
407 8356 : isInitPlan = true;
408 8356 : result = (Node *) prm;
409 : }
410 25094 : 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 25014 : 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 24996 : 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 24864 : 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 24360 : splan->testexpr = testexpr;
506 24360 : 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 24864 : if (subLinkType == ANY_SUBLINK &&
517 3878 : splan->parParam == NIL &&
518 3820 : subplan_is_hashable(plan) &&
519 1910 : testexpr_is_hashable(splan->testexpr, splan->paramIds))
520 1886 : 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 22978 : else if (splan->parParam == NIL && enable_material &&
533 42 : !ExecMaterializesOutput(nodeTag(plan)))
534 42 : plan = materialize_finished_plan(plan);
535 :
536 24864 : result = (Node *) splan;
537 24864 : isInitPlan = false;
538 : }
539 :
540 : /*
541 : * Add the subplan, its path, and its PlannerInfo to the global lists.
542 : */
543 33644 : root->glob->subplans = lappend(root->glob->subplans, plan);
544 33644 : root->glob->subpaths = lappend(root->glob->subpaths, path);
545 33644 : root->glob->subroots = lappend(root->glob->subroots, subroot);
546 33644 : splan->plan_id = list_length(root->glob->subplans);
547 :
548 33644 : if (isInitPlan)
549 8678 : 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 33644 : 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 33644 : 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 33644 : cost_subplan(root, splan, plan);
569 :
570 33644 : 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 1430 : generate_subquery_vars(PlannerInfo *root, List *tlist, Index varno)
614 : {
615 : List *result;
616 : ListCell *lc;
617 :
618 1430 : result = NIL;
619 2908 : foreach(lc, tlist)
620 : {
621 1478 : TargetEntry *tent = (TargetEntry *) lfirst(lc);
622 : Var *var;
623 :
624 1478 : if (tent->resjunk)
625 0 : continue;
626 :
627 1478 : var = makeVarFromTargetEntry(varno, tent);
628 1478 : result = lappend(result, var);
629 : }
630 :
631 1430 : 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 1952 : convert_testexpr(PlannerInfo *root,
643 : Node *testexpr,
644 : List *subst_nodes)
645 : {
646 : convert_testexpr_context context;
647 :
648 1952 : context.root = root;
649 1952 : context.subst_nodes = subst_nodes;
650 1952 : return convert_testexpr_mutator(testexpr, &context);
651 : }
652 :
653 : static Node *
654 9872 : convert_testexpr_mutator(Node *node,
655 : convert_testexpr_context *context)
656 : {
657 9872 : if (node == NULL)
658 46 : return NULL;
659 9826 : if (IsA(node, Param))
660 : {
661 2124 : Param *param = (Param *) node;
662 :
663 2124 : if (param->paramkind == PARAM_SUBLINK)
664 : {
665 4248 : if (param->paramid <= 0 ||
666 2124 : 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 2124 : return (Node *) copyObject(list_nth(context->subst_nodes,
675 : param->paramid - 1));
676 : }
677 : }
678 7702 : 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 7690 : 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 1910 : 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 1910 : subquery_size = plan->plan_rows *
723 1910 : (MAXALIGN(plan->plan_width) + MAXALIGN(SizeofHeapTupleHeader));
724 1910 : if (subquery_size > get_hash_memory_limit())
725 0 : return false;
726 :
727 1910 : 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 1494 : 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 1494 : subquery_size = path->rows *
747 1494 : (MAXALIGN(path->pathtarget->width) + MAXALIGN(SizeofHeapTupleHeader));
748 1494 : if (subquery_size > get_hash_memory_limit())
749 0 : return false;
750 :
751 1494 : 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 1910 : 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 1910 : if (testexpr && IsA(testexpr, OpExpr))
768 : {
769 1068 : if (test_opexpr_is_hashable((OpExpr *) testexpr, param_ids))
770 1044 : 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 2752 : 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 2752 : 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 2740 : if (list_length(testexpr->args) != 2)
817 0 : return false;
818 2740 : if (contain_exec_param((Node *) linitial(testexpr->args), param_ids))
819 12 : return false;
820 2728 : if (contain_var_clause((Node *) lsecond(testexpr->args)))
821 0 : return false;
822 2728 : 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 7906 : hash_ok_operator(OpExpr *expr)
833 : {
834 7906 : Oid opid = expr->opno;
835 :
836 : /* quick out if not a binary operator */
837 7906 : if (list_length(expr->args) != 2)
838 0 : return false;
839 7906 : 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 7894 : tup = SearchSysCache1(OPEROID, ObjectIdGetDatum(opid));
854 7894 : if (!HeapTupleIsValid(tup))
855 0 : elog(ERROR, "cache lookup failed for operator %u", opid);
856 7894 : optup = (Form_pg_operator) GETSTRUCT(tup);
857 7894 : if (!optup->oprcanhash || !func_strict(optup->oprcode))
858 : {
859 610 : ReleaseSysCache(tup);
860 610 : return false;
861 : }
862 7284 : ReleaseSysCache(tup);
863 7284 : 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 2400 : SS_process_ctes(PlannerInfo *root)
881 : {
882 : ListCell *lc;
883 :
884 : Assert(root->cte_plan_ids == NIL);
885 :
886 5810 : foreach(lc, root->parse->cteList)
887 : {
888 3416 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
889 3416 : 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 3416 : if (cte->cterefcount == 0 && cmdType == CMD_SELECT)
902 : {
903 : /* Make a dummy entry in cte_plan_ids */
904 18 : root->cte_plan_ids = lappend_int(root->cte_plan_ids, -1);
905 1380 : 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 3398 : if ((cte->ctematerialized == CTEMaterializeNever ||
940 3350 : (cte->ctematerialized == CTEMaterializeDefault &&
941 3160 : cte->cterefcount == 1)) &&
942 2442 : !cte->cterecursive &&
943 1448 : cmdType == CMD_SELECT &&
944 1448 : !contain_dml(cte->ctequery) &&
945 1440 : (cte->cterefcount <= 1 ||
946 36 : !contain_outer_selfref(cte->ctequery)) &&
947 1428 : !contain_volatile_functions(cte->ctequery))
948 : {
949 1362 : inline_cte(root, cte);
950 : /* Make a dummy entry in cte_plan_ids */
951 1362 : root->cte_plan_ids = lappend_int(root->cte_plan_ids, -1);
952 1362 : 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 2036 : 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 2036 : subroot = subquery_planner(root->glob, subquery, root,
969 2036 : 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 2030 : 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 2030 : final_rel = fetch_upper_rel(subroot, UPPERREL_FINAL, NULL);
984 2030 : best_path = final_rel->cheapest_total_path;
985 :
986 2030 : 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 2030 : splan = makeNode(SubPlan);
995 2030 : splan->subLinkType = CTE_SUBLINK;
996 2030 : splan->testexpr = NULL;
997 2030 : splan->paramIds = NIL;
998 2030 : get_first_col_type(plan, &splan->firstColType, &splan->firstColTypmod,
999 : &splan->firstColCollation);
1000 2030 : splan->useHashTable = false;
1001 2030 : splan->unknownEqFalse = false;
1002 :
1003 : /*
1004 : * CTE scans are not considered for parallelism (cf
1005 : * set_rel_consider_parallel).
1006 : */
1007 2030 : splan->parallel_safe = false;
1008 2030 : splan->setParam = NIL;
1009 2030 : splan->parParam = NIL;
1010 2030 : 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 2030 : paramid = assign_special_exec_param(root);
1028 2030 : splan->setParam = list_make1_int(paramid);
1029 :
1030 : /*
1031 : * Add the subplan, its path, and its PlannerInfo to the global lists.
1032 : */
1033 2030 : root->glob->subplans = lappend(root->glob->subplans, plan);
1034 2030 : root->glob->subpaths = lappend(root->glob->subpaths, best_path);
1035 2030 : root->glob->subroots = lappend(root->glob->subroots, subroot);
1036 2030 : splan->plan_id = list_length(root->glob->subplans);
1037 :
1038 2030 : root->init_plans = lappend(root->init_plans, splan);
1039 :
1040 2030 : root->cte_plan_ids = lappend_int(root->cte_plan_ids, splan->plan_id);
1041 :
1042 : /* Label the subplan for EXPLAIN purposes */
1043 2030 : splan->plan_name = psprintf("CTE %s", cte->ctename);
1044 :
1045 : /* Lastly, fill in the cost estimates for use later */
1046 2030 : cost_subplan(root, splan, plan);
1047 : }
1048 2394 : }
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 1448 : contain_dml(Node *node)
1057 : {
1058 1448 : return contain_dml_walker(node, NULL);
1059 : }
1060 :
1061 : static bool
1062 100236 : contain_dml_walker(Node *node, void *context)
1063 : {
1064 100236 : if (node == NULL)
1065 32130 : return false;
1066 68106 : if (IsA(node, Query))
1067 : {
1068 2514 : Query *query = (Query *) node;
1069 :
1070 2514 : if (query->commandType != CMD_SELECT ||
1071 2514 : query->rowMarks != NIL)
1072 8 : return true;
1073 :
1074 2506 : return query_tree_walker(query, contain_dml_walker, context, 0);
1075 : }
1076 65592 : 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 1362 : inline_cte(PlannerInfo *root, CommonTableExpr *cte)
1139 : {
1140 : struct inline_cte_walker_context context;
1141 :
1142 1362 : context.ctename = cte->ctename;
1143 : /* Start at levelsup = -1 because we'll immediately increment it */
1144 1362 : context.levelsup = -1;
1145 1362 : context.ctequery = castNode(Query, cte->ctequery);
1146 :
1147 1362 : (void) inline_cte_walker((Node *) root->parse, &context);
1148 1362 : }
1149 :
1150 : static bool
1151 513386 : inline_cte_walker(Node *node, inline_cte_walker_context *context)
1152 : {
1153 513386 : if (node == NULL)
1154 136242 : return false;
1155 377144 : if (IsA(node, Query))
1156 : {
1157 10002 : Query *query = (Query *) node;
1158 :
1159 10002 : 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 10002 : (void) query_tree_walker(query, inline_cte_walker, context,
1167 : QTW_EXAMINE_RTES_AFTER);
1168 :
1169 10002 : context->levelsup--;
1170 :
1171 10002 : return false;
1172 : }
1173 367142 : else if (IsA(node, RangeTblEntry))
1174 : {
1175 18568 : RangeTblEntry *rte = (RangeTblEntry *) node;
1176 :
1177 18568 : if (rte->rtekind == RTE_CTE &&
1178 5560 : strcmp(rte->ctename, context->ctename) == 0 &&
1179 1392 : 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 1386 : Query *newquery = copyObject(context->ctequery);
1187 :
1188 1386 : if (context->levelsup > 0)
1189 846 : 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 1386 : rte->rtekind = RTE_SUBQUERY;
1200 1386 : rte->subquery = newquery;
1201 1386 : rte->security_barrier = false;
1202 :
1203 : /* Zero out CTE-specific fields */
1204 1386 : rte->ctename = NULL;
1205 1386 : rte->ctelevelsup = 0;
1206 1386 : rte->self_reference = false;
1207 1386 : rte->coltypes = NIL;
1208 1386 : rte->coltypmods = NIL;
1209 1386 : rte->colcollations = NIL;
1210 : }
1211 :
1212 18568 : return false;
1213 : }
1214 :
1215 348574 : 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 1530 : convert_ANY_sublink_to_join(PlannerInfo *root, SubLink *sublink,
1255 : Relids available_rels)
1256 : {
1257 : JoinExpr *result;
1258 1530 : Query *parse = root->parse;
1259 1530 : 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 refers to any Vars of the parent query, we so let's
1275 : * considering it as LATERAL. (Vars of higher levels don't matter here.)
1276 : */
1277 1530 : sub_ref_outer_relids = pull_varnos_of_level(NULL, (Node *) subselect, 1);
1278 1530 : use_lateral = !bms_is_empty(sub_ref_outer_relids);
1279 :
1280 : /*
1281 : * Check that sub-select refers nothing outside of available_rels of the
1282 : * parent query.
1283 : */
1284 1530 : 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 1518 : upper_varnos = pull_varnos(root, sublink->testexpr);
1293 1518 : 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 1506 : 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 1494 : if (contain_volatile_functions(sublink->testexpr))
1306 64 : return NULL;
1307 :
1308 : /* Create a dummy ParseState for addRangeTableEntryForSubquery */
1309 1430 : 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 1430 : nsitem = addRangeTableEntryForSubquery(pstate,
1320 : subselect,
1321 : makeAlias("ANY_subquery", NIL),
1322 : use_lateral,
1323 : false);
1324 1430 : rte = nsitem->p_rte;
1325 1430 : parse->rtable = lappend(parse->rtable, rte);
1326 1430 : rtindex = list_length(parse->rtable);
1327 :
1328 : /*
1329 : * Form a RangeTblRef for the pulled-up sub-select.
1330 : */
1331 1430 : rtr = makeNode(RangeTblRef);
1332 1430 : rtr->rtindex = rtindex;
1333 :
1334 : /*
1335 : * Build a list of Vars representing the subselect outputs.
1336 : */
1337 1430 : 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 1430 : quals = convert_testexpr(root, sublink->testexpr, subquery_vars);
1345 :
1346 : /*
1347 : * And finally, build the JoinExpr node.
1348 : */
1349 1430 : result = makeNode(JoinExpr);
1350 1430 : result->jointype = JOIN_SEMI;
1351 1430 : result->isNatural = false;
1352 1430 : result->larg = NULL; /* caller must fill this in */
1353 1430 : result->rarg = (Node *) rtr;
1354 1430 : result->usingClause = NIL;
1355 1430 : result->join_using_alias = NULL;
1356 1430 : result->quals = quals;
1357 1430 : result->alias = NULL;
1358 1430 : result->rtindex = 0; /* we don't need an RTE for it */
1359 :
1360 1430 : 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 3224 : convert_EXISTS_sublink_to_join(PlannerInfo *root, SubLink *sublink,
1372 : bool under_not, Relids available_rels)
1373 : {
1374 : JoinExpr *result;
1375 3224 : Query *parse = root->parse;
1376 3224 : 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 3224 : 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 3224 : 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 3224 : 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 3192 : whereClause = subselect->jointree->quals;
1417 3192 : 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 3192 : if (contain_vars_of_level((Node *) subselect, 1))
1424 12 : 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 3180 : if (!contain_vars_of_level(whereClause, 1))
1431 56 : return NULL;
1432 :
1433 : /*
1434 : * We don't risk optimizing if the WHERE clause is volatile, either.
1435 : */
1436 3124 : 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 3124 : 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 3124 : rtoffset = list_length(parse->rtable);
1460 3124 : OffsetVarNodes((Node *) subselect, rtoffset, 0);
1461 3124 : 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 3124 : IncrementVarSublevelsUp((Node *) subselect, -1, 1);
1469 3124 : 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 3124 : clause_varnos = pull_varnos(root, whereClause);
1478 3124 : upper_varnos = NULL;
1479 3124 : varno = -1;
1480 9396 : while ((varno = bms_next_member(clause_varnos, varno)) >= 0)
1481 : {
1482 6272 : if (varno <= rtoffset)
1483 3148 : upper_varnos = bms_add_member(upper_varnos, varno);
1484 : }
1485 3124 : 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 3124 : 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 3092 : CombineRangeTables(&parse->rtable, &parse->rteperminfos,
1500 : subselect->rtable, subselect->rteperminfos);
1501 :
1502 : /*
1503 : * And finally, build the JoinExpr node.
1504 : */
1505 3092 : result = makeNode(JoinExpr);
1506 3092 : result->jointype = under_not ? JOIN_ANTI : JOIN_SEMI;
1507 3092 : result->isNatural = false;
1508 3092 : result->larg = NULL; /* caller must fill this in */
1509 : /* flatten out the FromExpr node if it's useless */
1510 3092 : if (list_length(subselect->jointree->fromlist) == 1)
1511 3074 : result->rarg = (Node *) linitial(subselect->jointree->fromlist);
1512 : else
1513 18 : result->rarg = (Node *) subselect->jointree;
1514 3092 : result->usingClause = NIL;
1515 3092 : result->join_using_alias = NULL;
1516 3092 : result->quals = whereClause;
1517 3092 : result->alias = NULL;
1518 3092 : result->rtindex = 0; /* we don't need an RTE for it */
1519 :
1520 3092 : 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 7078 : simplify_EXISTS_query(PlannerInfo *root, Query *query)
1541 : {
1542 : /*
1543 : * We don't try to simplify at all if the query uses set operations,
1544 : * aggregates, grouping sets, SRFs, modifying CTEs, HAVING, OFFSET, or FOR
1545 : * UPDATE/SHARE; none of these seem likely in normal usage and their
1546 : * possible effects are complex. (Note: we could ignore an "OFFSET 0"
1547 : * clause, but that traditionally is used as an optimization fence, so we
1548 : * don't.)
1549 : */
1550 7078 : if (query->commandType != CMD_SELECT ||
1551 7078 : query->setOperations ||
1552 7078 : query->hasAggs ||
1553 7078 : query->groupingSets ||
1554 7078 : query->hasWindowFuncs ||
1555 7078 : query->hasTargetSRFs ||
1556 7078 : query->hasModifyingCTE ||
1557 7078 : query->havingQual ||
1558 7078 : query->limitOffset ||
1559 7054 : query->rowMarks)
1560 52 : return false;
1561 :
1562 : /*
1563 : * LIMIT with a constant positive (or NULL) value doesn't affect the
1564 : * semantics of EXISTS, so let's ignore such clauses. This is worth doing
1565 : * because people accustomed to certain other DBMSes may be in the habit
1566 : * of writing EXISTS(SELECT ... LIMIT 1) as an optimization. If there's a
1567 : * LIMIT with anything else as argument, though, we can't simplify.
1568 : */
1569 7026 : if (query->limitCount)
1570 : {
1571 : /*
1572 : * The LIMIT clause has not yet been through eval_const_expressions,
1573 : * so we have to apply that here. It might seem like this is a waste
1574 : * of cycles, since the only case plausibly worth worrying about is
1575 : * "LIMIT 1" ... but what we'll actually see is "LIMIT int8(1::int4)",
1576 : * so we have to fold constants or we're not going to recognize it.
1577 : */
1578 24 : Node *node = eval_const_expressions(root, query->limitCount);
1579 : Const *limit;
1580 :
1581 : /* Might as well update the query if we simplified the clause. */
1582 24 : query->limitCount = node;
1583 :
1584 24 : if (!IsA(node, Const))
1585 0 : return false;
1586 :
1587 24 : limit = (Const *) node;
1588 : Assert(limit->consttype == INT8OID);
1589 24 : if (!limit->constisnull && DatumGetInt64(limit->constvalue) <= 0)
1590 12 : return false;
1591 :
1592 : /* Whether or not the targetlist is safe, we can drop the LIMIT. */
1593 12 : query->limitCount = NULL;
1594 : }
1595 :
1596 : /*
1597 : * Otherwise, we can throw away the targetlist, as well as any GROUP,
1598 : * WINDOW, DISTINCT, and ORDER BY clauses; none of those clauses will
1599 : * change a nonzero-rows result to zero rows or vice versa. (Furthermore,
1600 : * since our parsetree representation of these clauses depends on the
1601 : * targetlist, we'd better throw them away if we drop the targetlist.)
1602 : */
1603 7014 : query->targetList = NIL;
1604 7014 : query->groupClause = NIL;
1605 7014 : query->windowClause = NIL;
1606 7014 : query->distinctClause = NIL;
1607 7014 : query->sortClause = NIL;
1608 7014 : query->hasDistinctOn = false;
1609 :
1610 7014 : return true;
1611 : }
1612 :
1613 : /*
1614 : * convert_EXISTS_to_ANY: try to convert EXISTS to a hashable ANY sublink
1615 : *
1616 : * The subselect is expected to be a fresh copy that we can munge up,
1617 : * and to have been successfully passed through simplify_EXISTS_query.
1618 : *
1619 : * On success, the modified subselect is returned, and we store a suitable
1620 : * upper-level test expression at *testexpr, plus a list of the subselect's
1621 : * output Params at *paramIds. (The test expression is already Param-ified
1622 : * and hence need not go through convert_testexpr, which is why we have to
1623 : * deal with the Param IDs specially.)
1624 : *
1625 : * On failure, returns NULL.
1626 : */
1627 : static Query *
1628 1814 : convert_EXISTS_to_ANY(PlannerInfo *root, Query *subselect,
1629 : Node **testexpr, List **paramIds)
1630 : {
1631 : Node *whereClause;
1632 : List *leftargs,
1633 : *rightargs,
1634 : *opids,
1635 : *opcollations,
1636 : *newWhere,
1637 : *tlist,
1638 : *testlist,
1639 : *paramids;
1640 : ListCell *lc,
1641 : *rc,
1642 : *oc,
1643 : *cc;
1644 : AttrNumber resno;
1645 :
1646 : /*
1647 : * Query must not require a targetlist, since we have to insert a new one.
1648 : * Caller should have dealt with the case already.
1649 : */
1650 : Assert(subselect->targetList == NIL);
1651 :
1652 : /*
1653 : * Separate out the WHERE clause. (We could theoretically also remove
1654 : * top-level plain JOIN/ON clauses, but it's probably not worth the
1655 : * trouble.)
1656 : */
1657 1814 : whereClause = subselect->jointree->quals;
1658 1814 : subselect->jointree->quals = NULL;
1659 :
1660 : /*
1661 : * The rest of the sub-select must not refer to any Vars of the parent
1662 : * query. (Vars of higher levels should be okay, though.)
1663 : *
1664 : * Note: we need not check for Aggrefs separately because we know the
1665 : * sub-select is as yet unoptimized; any uplevel Aggref must therefore
1666 : * contain an uplevel Var reference. This is not the case below ...
1667 : */
1668 1814 : if (contain_vars_of_level((Node *) subselect, 1))
1669 18 : return NULL;
1670 :
1671 : /*
1672 : * We don't risk optimizing if the WHERE clause is volatile, either.
1673 : */
1674 1796 : if (contain_volatile_functions(whereClause))
1675 0 : return NULL;
1676 :
1677 : /*
1678 : * Clean up the WHERE clause by doing const-simplification etc on it.
1679 : * Aside from simplifying the processing we're about to do, this is
1680 : * important for being able to pull chunks of the WHERE clause up into the
1681 : * parent query. Since we are invoked partway through the parent's
1682 : * preprocess_expression() work, earlier steps of preprocess_expression()
1683 : * wouldn't get applied to the pulled-up stuff unless we do them here. For
1684 : * the parts of the WHERE clause that get put back into the child query,
1685 : * this work is partially duplicative, but it shouldn't hurt.
1686 : *
1687 : * Note: we do not run flatten_join_alias_vars. This is OK because any
1688 : * parent aliases were flattened already, and we're not going to pull any
1689 : * child Vars (of any description) into the parent.
1690 : *
1691 : * Note: passing the parent's root to eval_const_expressions is
1692 : * technically wrong, but we can get away with it since only the
1693 : * boundParams (if any) are used, and those would be the same in a
1694 : * subroot.
1695 : */
1696 1796 : whereClause = eval_const_expressions(root, whereClause);
1697 1796 : whereClause = (Node *) canonicalize_qual((Expr *) whereClause, false);
1698 1796 : whereClause = (Node *) make_ands_implicit((Expr *) whereClause);
1699 :
1700 : /*
1701 : * We now have a flattened implicit-AND list of clauses, which we try to
1702 : * break apart into "outervar = innervar" hash clauses. Anything that
1703 : * can't be broken apart just goes back into the newWhere list. Note that
1704 : * we aren't trying hard yet to ensure that we have only outer or only
1705 : * inner on each side; we'll check that if we get to the end.
1706 : */
1707 1796 : leftargs = rightargs = opids = opcollations = newWhere = NIL;
1708 6866 : foreach(lc, (List *) whereClause)
1709 : {
1710 5070 : OpExpr *expr = (OpExpr *) lfirst(lc);
1711 :
1712 8286 : if (IsA(expr, OpExpr) &&
1713 3216 : hash_ok_operator(expr))
1714 : {
1715 2606 : Node *leftarg = (Node *) linitial(expr->args);
1716 2606 : Node *rightarg = (Node *) lsecond(expr->args);
1717 :
1718 2606 : if (contain_vars_of_level(leftarg, 1))
1719 : {
1720 332 : leftargs = lappend(leftargs, leftarg);
1721 332 : rightargs = lappend(rightargs, rightarg);
1722 332 : opids = lappend_oid(opids, expr->opno);
1723 332 : opcollations = lappend_oid(opcollations, expr->inputcollid);
1724 332 : continue;
1725 : }
1726 2274 : if (contain_vars_of_level(rightarg, 1))
1727 : {
1728 : /*
1729 : * We must commute the clause to put the outer var on the
1730 : * left, because the hashing code in nodeSubplan.c expects
1731 : * that. This probably shouldn't ever fail, since hashable
1732 : * operators ought to have commutators, but be paranoid.
1733 : */
1734 1938 : expr->opno = get_commutator(expr->opno);
1735 1938 : if (OidIsValid(expr->opno) && hash_ok_operator(expr))
1736 : {
1737 1938 : leftargs = lappend(leftargs, rightarg);
1738 1938 : rightargs = lappend(rightargs, leftarg);
1739 1938 : opids = lappend_oid(opids, expr->opno);
1740 1938 : opcollations = lappend_oid(opcollations, expr->inputcollid);
1741 1938 : continue;
1742 : }
1743 : /* If no commutator, no chance to optimize the WHERE clause */
1744 0 : return NULL;
1745 : }
1746 : }
1747 : /* Couldn't handle it as a hash clause */
1748 2800 : newWhere = lappend(newWhere, expr);
1749 : }
1750 :
1751 : /*
1752 : * If we didn't find anything we could convert, fail.
1753 : */
1754 1796 : if (leftargs == NIL)
1755 302 : return NULL;
1756 :
1757 : /*
1758 : * There mustn't be any parent Vars or Aggs in the stuff that we intend to
1759 : * put back into the child query. Note: you might think we don't need to
1760 : * check for Aggs separately, because an uplevel Agg must contain an
1761 : * uplevel Var in its argument. But it is possible that the uplevel Var
1762 : * got optimized away by eval_const_expressions. Consider
1763 : *
1764 : * SUM(CASE WHEN false THEN uplevelvar ELSE 0 END)
1765 : */
1766 2988 : if (contain_vars_of_level((Node *) newWhere, 1) ||
1767 1494 : contain_vars_of_level((Node *) rightargs, 1))
1768 0 : return NULL;
1769 1536 : if (root->parse->hasAggs &&
1770 84 : (contain_aggs_of_level((Node *) newWhere, 1) ||
1771 42 : contain_aggs_of_level((Node *) rightargs, 1)))
1772 0 : return NULL;
1773 :
1774 : /*
1775 : * And there can't be any child Vars in the stuff we intend to pull up.
1776 : * (Note: we'd need to check for child Aggs too, except we know the child
1777 : * has no aggs at all because of simplify_EXISTS_query's check. The same
1778 : * goes for window functions.)
1779 : */
1780 1494 : if (contain_vars_of_level((Node *) leftargs, 0))
1781 0 : return NULL;
1782 :
1783 : /*
1784 : * Also reject sublinks in the stuff we intend to pull up. (It might be
1785 : * possible to support this, but doesn't seem worth the complication.)
1786 : */
1787 1494 : if (contain_subplans((Node *) leftargs))
1788 0 : return NULL;
1789 :
1790 : /*
1791 : * Okay, adjust the sublevelsup in the stuff we're pulling up.
1792 : */
1793 1494 : IncrementVarSublevelsUp((Node *) leftargs, -1, 1);
1794 :
1795 : /*
1796 : * Put back any child-level-only WHERE clauses.
1797 : */
1798 1494 : if (newWhere)
1799 1302 : subselect->jointree->quals = (Node *) make_ands_explicit(newWhere);
1800 :
1801 : /*
1802 : * Build a new targetlist for the child that emits the expressions we
1803 : * need. Concurrently, build a testexpr for the parent using Params to
1804 : * reference the child outputs. (Since we generate Params directly here,
1805 : * there will be no need to convert the testexpr in build_subplan.)
1806 : */
1807 1494 : tlist = testlist = paramids = NIL;
1808 1494 : resno = 1;
1809 3764 : forfour(lc, leftargs, rc, rightargs, oc, opids, cc, opcollations)
1810 : {
1811 2270 : Node *leftarg = (Node *) lfirst(lc);
1812 2270 : Node *rightarg = (Node *) lfirst(rc);
1813 2270 : Oid opid = lfirst_oid(oc);
1814 2270 : Oid opcollation = lfirst_oid(cc);
1815 : Param *param;
1816 :
1817 2270 : param = generate_new_exec_param(root,
1818 : exprType(rightarg),
1819 : exprTypmod(rightarg),
1820 : exprCollation(rightarg));
1821 2270 : tlist = lappend(tlist,
1822 2270 : makeTargetEntry((Expr *) rightarg,
1823 2270 : resno++,
1824 : NULL,
1825 : false));
1826 2270 : testlist = lappend(testlist,
1827 2270 : make_opclause(opid, BOOLOID, false,
1828 : (Expr *) leftarg, (Expr *) param,
1829 : InvalidOid, opcollation));
1830 2270 : paramids = lappend_int(paramids, param->paramid);
1831 : }
1832 :
1833 : /* Put everything where it should go, and we're done */
1834 1494 : subselect->targetList = tlist;
1835 1494 : *testexpr = (Node *) make_ands_explicit(testlist);
1836 1494 : *paramIds = paramids;
1837 :
1838 1494 : return subselect;
1839 : }
1840 :
1841 :
1842 : /*
1843 : * Replace correlation vars (uplevel vars) with Params.
1844 : *
1845 : * Uplevel PlaceHolderVars, aggregates, GROUPING() expressions, and
1846 : * MergeSupportFuncs are replaced, too.
1847 : *
1848 : * Note: it is critical that this runs immediately after SS_process_sublinks.
1849 : * Since we do not recurse into the arguments of uplevel PHVs and aggregates,
1850 : * they will get copied to the appropriate subplan args list in the parent
1851 : * query with uplevel vars not replaced by Params, but only adjusted in level
1852 : * (see replace_outer_placeholdervar and replace_outer_agg). That's exactly
1853 : * what we want for the vars of the parent level --- but if a PHV's or
1854 : * aggregate's argument contains any further-up variables, they have to be
1855 : * replaced with Params in their turn. That will happen when the parent level
1856 : * runs SS_replace_correlation_vars. Therefore it must do so after expanding
1857 : * its sublinks to subplans. And we don't want any steps in between, else
1858 : * those steps would never get applied to the argument expressions, either in
1859 : * the parent or the child level.
1860 : *
1861 : * Another fairly tricky thing going on here is the handling of SubLinks in
1862 : * the arguments of uplevel PHVs/aggregates. Those are not touched inside the
1863 : * intermediate query level, either. Instead, SS_process_sublinks recurses on
1864 : * them after copying the PHV or Aggref expression into the parent plan level
1865 : * (this is actually taken care of in build_subplan).
1866 : */
1867 : Node *
1868 126578 : SS_replace_correlation_vars(PlannerInfo *root, Node *expr)
1869 : {
1870 : /* No setup needed for tree walk, so away we go */
1871 126578 : return replace_correlation_vars_mutator(expr, root);
1872 : }
1873 :
1874 : static Node *
1875 1010200 : replace_correlation_vars_mutator(Node *node, PlannerInfo *root)
1876 : {
1877 1010200 : if (node == NULL)
1878 44388 : return NULL;
1879 965812 : if (IsA(node, Var))
1880 : {
1881 259394 : if (((Var *) node)->varlevelsup > 0)
1882 44968 : return (Node *) replace_outer_var(root, (Var *) node);
1883 : }
1884 920844 : if (IsA(node, PlaceHolderVar))
1885 : {
1886 84 : if (((PlaceHolderVar *) node)->phlevelsup > 0)
1887 42 : return (Node *) replace_outer_placeholdervar(root,
1888 : (PlaceHolderVar *) node);
1889 : }
1890 920802 : if (IsA(node, Aggref))
1891 : {
1892 7102 : if (((Aggref *) node)->agglevelsup > 0)
1893 52 : return (Node *) replace_outer_agg(root, (Aggref *) node);
1894 : }
1895 920750 : if (IsA(node, GroupingFunc))
1896 : {
1897 90 : if (((GroupingFunc *) node)->agglevelsup > 0)
1898 64 : return (Node *) replace_outer_grouping(root, (GroupingFunc *) node);
1899 : }
1900 920686 : if (IsA(node, MergeSupportFunc))
1901 : {
1902 24 : if (root->parse->commandType != CMD_MERGE)
1903 6 : return (Node *) replace_outer_merge_support(root,
1904 : (MergeSupportFunc *) node);
1905 : }
1906 920680 : return expression_tree_mutator(node,
1907 : replace_correlation_vars_mutator,
1908 : (void *) root);
1909 : }
1910 :
1911 : /*
1912 : * Expand SubLinks to SubPlans in the given expression.
1913 : *
1914 : * The isQual argument tells whether or not this expression is a WHERE/HAVING
1915 : * qualifier expression. If it is, any sublinks appearing at top level need
1916 : * not distinguish FALSE from UNKNOWN return values.
1917 : */
1918 : Node *
1919 77630 : SS_process_sublinks(PlannerInfo *root, Node *expr, bool isQual)
1920 : {
1921 : process_sublinks_context context;
1922 :
1923 77630 : context.root = root;
1924 77630 : context.isTopQual = isQual;
1925 77630 : return process_sublinks_mutator(expr, &context);
1926 : }
1927 :
1928 : static Node *
1929 1080550 : process_sublinks_mutator(Node *node, process_sublinks_context *context)
1930 : {
1931 : process_sublinks_context locContext;
1932 :
1933 1080550 : locContext.root = context->root;
1934 :
1935 1080550 : if (node == NULL)
1936 49914 : return NULL;
1937 1030636 : if (IsA(node, SubLink))
1938 : {
1939 32150 : SubLink *sublink = (SubLink *) node;
1940 : Node *testexpr;
1941 :
1942 : /*
1943 : * First, recursively process the lefthand-side expressions, if any.
1944 : * They're not top-level anymore.
1945 : */
1946 32150 : locContext.isTopQual = false;
1947 32150 : testexpr = process_sublinks_mutator(sublink->testexpr, &locContext);
1948 :
1949 : /*
1950 : * Now build the SubPlan node and make the expr to return.
1951 : */
1952 32150 : return make_subplan(context->root,
1953 32150 : (Query *) sublink->subselect,
1954 : sublink->subLinkType,
1955 : sublink->subLinkId,
1956 : testexpr,
1957 32150 : context->isTopQual);
1958 : }
1959 :
1960 : /*
1961 : * Don't recurse into the arguments of an outer PHV, Aggref or
1962 : * GroupingFunc here. Any SubLinks in the arguments have to be dealt with
1963 : * at the outer query level; they'll be handled when build_subplan
1964 : * collects the PHV, Aggref or GroupingFunc into the arguments to be
1965 : * passed down to the current subplan.
1966 : */
1967 998486 : if (IsA(node, PlaceHolderVar))
1968 : {
1969 162 : if (((PlaceHolderVar *) node)->phlevelsup > 0)
1970 0 : return node;
1971 : }
1972 998324 : else if (IsA(node, Aggref))
1973 : {
1974 572 : if (((Aggref *) node)->agglevelsup > 0)
1975 18 : return node;
1976 : }
1977 997752 : else if (IsA(node, GroupingFunc))
1978 : {
1979 112 : if (((GroupingFunc *) node)->agglevelsup > 0)
1980 36 : return node;
1981 : }
1982 :
1983 : /*
1984 : * We should never see a SubPlan expression in the input (since this is
1985 : * the very routine that creates 'em to begin with). We shouldn't find
1986 : * ourselves invoked directly on a Query, either.
1987 : */
1988 : Assert(!IsA(node, SubPlan));
1989 : Assert(!IsA(node, AlternativeSubPlan));
1990 : Assert(!IsA(node, Query));
1991 :
1992 : /*
1993 : * Because make_subplan() could return an AND or OR clause, we have to
1994 : * take steps to preserve AND/OR flatness of a qual. We assume the input
1995 : * has been AND/OR flattened and so we need no recursion here.
1996 : *
1997 : * (Due to the coding here, we will not get called on the List subnodes of
1998 : * an AND; and the input is *not* yet in implicit-AND format. So no check
1999 : * is needed for a bare List.)
2000 : *
2001 : * Anywhere within the top-level AND/OR clause structure, we can tell
2002 : * make_subplan() that NULL and FALSE are interchangeable. So isTopQual
2003 : * propagates down in both cases. (Note that this is unlike the meaning
2004 : * of "top level qual" used in most other places in Postgres.)
2005 : */
2006 998432 : if (is_andclause(node))
2007 : {
2008 14824 : List *newargs = NIL;
2009 : ListCell *l;
2010 :
2011 : /* Still at qual top-level */
2012 14824 : locContext.isTopQual = context->isTopQual;
2013 :
2014 55282 : foreach(l, ((BoolExpr *) node)->args)
2015 : {
2016 : Node *newarg;
2017 :
2018 40458 : newarg = process_sublinks_mutator(lfirst(l), &locContext);
2019 40458 : if (is_andclause(newarg))
2020 0 : newargs = list_concat(newargs, ((BoolExpr *) newarg)->args);
2021 : else
2022 40458 : newargs = lappend(newargs, newarg);
2023 : }
2024 14824 : return (Node *) make_andclause(newargs);
2025 : }
2026 :
2027 983608 : if (is_orclause(node))
2028 : {
2029 1932 : List *newargs = NIL;
2030 : ListCell *l;
2031 :
2032 : /* Still at qual top-level */
2033 1932 : locContext.isTopQual = context->isTopQual;
2034 :
2035 6800 : foreach(l, ((BoolExpr *) node)->args)
2036 : {
2037 : Node *newarg;
2038 :
2039 4868 : newarg = process_sublinks_mutator(lfirst(l), &locContext);
2040 4868 : if (is_orclause(newarg))
2041 0 : newargs = list_concat(newargs, ((BoolExpr *) newarg)->args);
2042 : else
2043 4868 : newargs = lappend(newargs, newarg);
2044 : }
2045 1932 : return (Node *) make_orclause(newargs);
2046 : }
2047 :
2048 : /*
2049 : * If we recurse down through anything other than an AND or OR node, we
2050 : * are definitely not at top qual level anymore.
2051 : */
2052 981676 : locContext.isTopQual = false;
2053 :
2054 981676 : return expression_tree_mutator(node,
2055 : process_sublinks_mutator,
2056 : (void *) &locContext);
2057 : }
2058 :
2059 : /*
2060 : * SS_identify_outer_params - identify the Params available from outer levels
2061 : *
2062 : * This must be run after SS_replace_correlation_vars and SS_process_sublinks
2063 : * processing is complete in a given query level as well as all of its
2064 : * descendant levels (which means it's most practical to do it at the end of
2065 : * processing the query level). We compute the set of paramIds that outer
2066 : * levels will make available to this level+descendants, and record it in
2067 : * root->outer_params for use while computing extParam/allParam sets in final
2068 : * plan cleanup. (We can't just compute it then, because the upper levels'
2069 : * plan_params lists are transient and will be gone by then.)
2070 : */
2071 : void
2072 488200 : SS_identify_outer_params(PlannerInfo *root)
2073 : {
2074 : Bitmapset *outer_params;
2075 : PlannerInfo *proot;
2076 : ListCell *l;
2077 :
2078 : /*
2079 : * If no parameters have been assigned anywhere in the tree, we certainly
2080 : * don't need to do anything here.
2081 : */
2082 488200 : if (root->glob->paramExecTypes == NIL)
2083 329778 : return;
2084 :
2085 : /*
2086 : * Scan all query levels above this one to see which parameters are due to
2087 : * be available from them, either because lower query levels have
2088 : * requested them (via plan_params) or because they will be available from
2089 : * initPlans of those levels.
2090 : */
2091 158422 : outer_params = NULL;
2092 204374 : for (proot = root->parent_root; proot != NULL; proot = proot->parent_root)
2093 : {
2094 : /* Include ordinary Var/PHV/Aggref/GroupingFunc params */
2095 84506 : foreach(l, proot->plan_params)
2096 : {
2097 38554 : PlannerParamItem *pitem = (PlannerParamItem *) lfirst(l);
2098 :
2099 38554 : outer_params = bms_add_member(outer_params, pitem->paramId);
2100 : }
2101 : /* Include any outputs of outer-level initPlans */
2102 50908 : foreach(l, proot->init_plans)
2103 : {
2104 4956 : SubPlan *initsubplan = (SubPlan *) lfirst(l);
2105 : ListCell *l2;
2106 :
2107 9912 : foreach(l2, initsubplan->setParam)
2108 : {
2109 4956 : outer_params = bms_add_member(outer_params, lfirst_int(l2));
2110 : }
2111 : }
2112 : /* Include worktable ID, if a recursive query is being planned */
2113 45952 : if (proot->wt_param_id >= 0)
2114 2360 : outer_params = bms_add_member(outer_params, proot->wt_param_id);
2115 : }
2116 158422 : root->outer_params = outer_params;
2117 : }
2118 :
2119 : /*
2120 : * SS_charge_for_initplans - account for initplans in Path costs & parallelism
2121 : *
2122 : * If any initPlans have been created in the current query level, they will
2123 : * get attached to the Plan tree created from whichever Path we select from
2124 : * the given rel. Increment all that rel's Paths' costs to account for them,
2125 : * and if any of the initPlans are parallel-unsafe, mark all the rel's Paths
2126 : * parallel-unsafe as well.
2127 : *
2128 : * This is separate from SS_attach_initplans because we might conditionally
2129 : * create more initPlans during create_plan(), depending on which Path we
2130 : * select. However, Paths that would generate such initPlans are expected
2131 : * to have included their cost and parallel-safety effects already.
2132 : */
2133 : void
2134 488200 : SS_charge_for_initplans(PlannerInfo *root, RelOptInfo *final_rel)
2135 : {
2136 : Cost initplan_cost;
2137 : bool unsafe_initplans;
2138 : ListCell *lc;
2139 :
2140 : /* Nothing to do if no initPlans */
2141 488200 : if (root->init_plans == NIL)
2142 478558 : return;
2143 :
2144 : /*
2145 : * Compute the cost increment just once, since it will be the same for all
2146 : * Paths. Also check for parallel-unsafe initPlans.
2147 : */
2148 9642 : SS_compute_initplan_cost(root->init_plans,
2149 : &initplan_cost, &unsafe_initplans);
2150 :
2151 : /*
2152 : * Now adjust the costs and parallel_safe flags.
2153 : */
2154 19416 : foreach(lc, final_rel->pathlist)
2155 : {
2156 9774 : Path *path = (Path *) lfirst(lc);
2157 :
2158 9774 : path->startup_cost += initplan_cost;
2159 9774 : path->total_cost += initplan_cost;
2160 9774 : if (unsafe_initplans)
2161 5584 : path->parallel_safe = false;
2162 : }
2163 :
2164 : /*
2165 : * Adjust partial paths' costs too, or forget them entirely if we must
2166 : * consider the rel parallel-unsafe.
2167 : */
2168 9642 : if (unsafe_initplans)
2169 : {
2170 5546 : final_rel->partial_pathlist = NIL;
2171 5546 : final_rel->consider_parallel = false;
2172 : }
2173 : else
2174 : {
2175 4108 : foreach(lc, final_rel->partial_pathlist)
2176 : {
2177 12 : Path *path = (Path *) lfirst(lc);
2178 :
2179 12 : path->startup_cost += initplan_cost;
2180 12 : path->total_cost += initplan_cost;
2181 : }
2182 : }
2183 :
2184 : /* We needn't do set_cheapest() here, caller will do it */
2185 : }
2186 :
2187 : /*
2188 : * SS_compute_initplan_cost - count up the cost delta for some initplans
2189 : *
2190 : * The total cost returned in *initplan_cost_p should be added to both the
2191 : * startup and total costs of the plan node the initplans get attached to.
2192 : * We also report whether any of the initplans are not parallel-safe.
2193 : *
2194 : * The primary user of this is SS_charge_for_initplans, but it's also
2195 : * used in adjusting costs when we move initplans to another plan node.
2196 : */
2197 : void
2198 9786 : SS_compute_initplan_cost(List *init_plans,
2199 : Cost *initplan_cost_p,
2200 : bool *unsafe_initplans_p)
2201 : {
2202 : Cost initplan_cost;
2203 : bool unsafe_initplans;
2204 : ListCell *lc;
2205 :
2206 : /*
2207 : * We assume each initPlan gets run once during top plan startup. This is
2208 : * a conservative overestimate, since in fact an initPlan might be
2209 : * executed later than plan startup, or even not at all.
2210 : */
2211 9786 : initplan_cost = 0;
2212 9786 : unsafe_initplans = false;
2213 20554 : foreach(lc, init_plans)
2214 : {
2215 10768 : SubPlan *initsubplan = lfirst_node(SubPlan, lc);
2216 :
2217 10768 : initplan_cost += initsubplan->startup_cost + initsubplan->per_call_cost;
2218 10768 : if (!initsubplan->parallel_safe)
2219 6444 : unsafe_initplans = true;
2220 : }
2221 9786 : *initplan_cost_p = initplan_cost;
2222 9786 : *unsafe_initplans_p = unsafe_initplans;
2223 9786 : }
2224 :
2225 : /*
2226 : * SS_attach_initplans - attach initplans to topmost plan node
2227 : *
2228 : * Attach any initplans created in the current query level to the specified
2229 : * plan node, which should normally be the topmost node for the query level.
2230 : * (In principle the initPlans could go in any node at or above where they're
2231 : * referenced; but there seems no reason to put them any lower than the
2232 : * topmost node, so we don't bother to track exactly where they came from.)
2233 : *
2234 : * We do not touch the plan node's cost or parallel_safe flag. The initplans
2235 : * must have been accounted for in SS_charge_for_initplans, or by any later
2236 : * code that adds initplans via SS_make_initplan_from_plan.
2237 : */
2238 : void
2239 487214 : SS_attach_initplans(PlannerInfo *root, Plan *plan)
2240 : {
2241 487214 : plan->initPlan = root->init_plans;
2242 487214 : }
2243 :
2244 : /*
2245 : * SS_finalize_plan - do final parameter processing for a completed Plan.
2246 : *
2247 : * This recursively computes the extParam and allParam sets for every Plan
2248 : * node in the given plan tree. (Oh, and RangeTblFunction.funcparams too.)
2249 : *
2250 : * We assume that SS_finalize_plan has already been run on any initplans or
2251 : * subplans the plan tree could reference.
2252 : */
2253 : void
2254 182148 : SS_finalize_plan(PlannerInfo *root, Plan *plan)
2255 : {
2256 : /* No setup needed, just recurse through plan tree. */
2257 182148 : (void) finalize_plan(root, plan, -1, root->outer_params, NULL);
2258 182148 : }
2259 :
2260 : /*
2261 : * Recursive processing of all nodes in the plan tree
2262 : *
2263 : * gather_param is the rescan_param of an ancestral Gather/GatherMerge,
2264 : * or -1 if there is none.
2265 : *
2266 : * valid_params is the set of param IDs supplied by outer plan levels
2267 : * that are valid to reference in this plan node or its children.
2268 : *
2269 : * scan_params is a set of param IDs to force scan plan nodes to reference.
2270 : * This is for EvalPlanQual support, and is always NULL at the top of the
2271 : * recursion.
2272 : *
2273 : * The return value is the computed allParam set for the given Plan node.
2274 : * This is just an internal notational convenience: we can add a child
2275 : * plan's allParams to the set of param IDs of interest to this level
2276 : * in the same statement that recurses to that child.
2277 : *
2278 : * Do not scribble on caller's values of valid_params or scan_params!
2279 : *
2280 : * Note: although we attempt to deal with initPlans anywhere in the tree, the
2281 : * logic is not really right. The problem is that a plan node might return an
2282 : * output Param of its initPlan as a targetlist item, in which case it's valid
2283 : * for the parent plan level to reference that same Param; the parent's usage
2284 : * will be converted into a Var referencing the child plan node by setrefs.c.
2285 : * But this function would see the parent's reference as out of scope and
2286 : * complain about it. For now, this does not matter because the planner only
2287 : * attaches initPlans to the topmost plan node in a query level, so the case
2288 : * doesn't arise. If we ever merge this processing into setrefs.c, maybe it
2289 : * can be handled more cleanly.
2290 : */
2291 : static Bitmapset *
2292 1341390 : finalize_plan(PlannerInfo *root, Plan *plan,
2293 : int gather_param,
2294 : Bitmapset *valid_params,
2295 : Bitmapset *scan_params)
2296 : {
2297 : finalize_primnode_context context;
2298 : int locally_added_param;
2299 : Bitmapset *nestloop_params;
2300 : Bitmapset *initExtParam;
2301 : Bitmapset *initSetParam;
2302 : Bitmapset *child_params;
2303 : ListCell *l;
2304 :
2305 1341390 : if (plan == NULL)
2306 781522 : return NULL;
2307 :
2308 559868 : context.root = root;
2309 559868 : context.paramids = NULL; /* initialize set to empty */
2310 559868 : locally_added_param = -1; /* there isn't one */
2311 559868 : nestloop_params = NULL; /* there aren't any */
2312 :
2313 : /*
2314 : * Examine any initPlans to determine the set of external params they
2315 : * reference and the set of output params they supply. (We assume
2316 : * SS_finalize_plan was run on them already.)
2317 : */
2318 559868 : initExtParam = initSetParam = NULL;
2319 570952 : foreach(l, plan->initPlan)
2320 : {
2321 11084 : SubPlan *initsubplan = (SubPlan *) lfirst(l);
2322 11084 : Plan *initplan = planner_subplan_get_plan(root, initsubplan);
2323 : ListCell *l2;
2324 :
2325 11084 : initExtParam = bms_add_members(initExtParam, initplan->extParam);
2326 22216 : foreach(l2, initsubplan->setParam)
2327 : {
2328 11132 : initSetParam = bms_add_member(initSetParam, lfirst_int(l2));
2329 : }
2330 : }
2331 :
2332 : /* Any setParams are validly referenceable in this node and children */
2333 559868 : if (initSetParam)
2334 9970 : valid_params = bms_union(valid_params, initSetParam);
2335 :
2336 : /*
2337 : * When we call finalize_primnode, context.paramids sets are automatically
2338 : * merged together. But when recursing to self, we have to do it the hard
2339 : * way. We want the paramids set to include params in subplans as well as
2340 : * at this level.
2341 : */
2342 :
2343 : /* Find params in targetlist and qual */
2344 559868 : finalize_primnode((Node *) plan->targetlist, &context);
2345 559868 : finalize_primnode((Node *) plan->qual, &context);
2346 :
2347 : /*
2348 : * If it's a parallel-aware scan node, mark it as dependent on the parent
2349 : * Gather/GatherMerge's rescan Param.
2350 : */
2351 559868 : if (plan->parallel_aware)
2352 : {
2353 2516 : if (gather_param < 0)
2354 0 : elog(ERROR, "parallel-aware plan node is not below a Gather");
2355 2516 : context.paramids =
2356 2516 : bms_add_member(context.paramids, gather_param);
2357 : }
2358 :
2359 : /* Check additional node-type-specific fields */
2360 559868 : switch (nodeTag(plan))
2361 : {
2362 74446 : case T_Result:
2363 74446 : finalize_primnode(((Result *) plan)->resconstantqual,
2364 : &context);
2365 74446 : break;
2366 :
2367 76956 : case T_SeqScan:
2368 76956 : context.paramids = bms_add_members(context.paramids, scan_params);
2369 76956 : break;
2370 :
2371 98 : case T_SampleScan:
2372 98 : finalize_primnode((Node *) ((SampleScan *) plan)->tablesample,
2373 : &context);
2374 98 : context.paramids = bms_add_members(context.paramids, scan_params);
2375 98 : break;
2376 :
2377 88186 : case T_IndexScan:
2378 88186 : finalize_primnode((Node *) ((IndexScan *) plan)->indexqual,
2379 : &context);
2380 88186 : finalize_primnode((Node *) ((IndexScan *) plan)->indexorderby,
2381 : &context);
2382 :
2383 : /*
2384 : * we need not look at indexqualorig, since it will have the same
2385 : * param references as indexqual. Likewise, we can ignore
2386 : * indexorderbyorig.
2387 : */
2388 88186 : context.paramids = bms_add_members(context.paramids, scan_params);
2389 88186 : break;
2390 :
2391 6498 : case T_IndexOnlyScan:
2392 6498 : finalize_primnode((Node *) ((IndexOnlyScan *) plan)->indexqual,
2393 : &context);
2394 6498 : finalize_primnode((Node *) ((IndexOnlyScan *) plan)->recheckqual,
2395 : &context);
2396 6498 : finalize_primnode((Node *) ((IndexOnlyScan *) plan)->indexorderby,
2397 : &context);
2398 :
2399 : /*
2400 : * we need not look at indextlist, since it cannot contain Params.
2401 : */
2402 6498 : context.paramids = bms_add_members(context.paramids, scan_params);
2403 6498 : break;
2404 :
2405 6858 : case T_BitmapIndexScan:
2406 6858 : finalize_primnode((Node *) ((BitmapIndexScan *) plan)->indexqual,
2407 : &context);
2408 :
2409 : /*
2410 : * we need not look at indexqualorig, since it will have the same
2411 : * param references as indexqual.
2412 : */
2413 6858 : break;
2414 :
2415 6646 : case T_BitmapHeapScan:
2416 6646 : finalize_primnode((Node *) ((BitmapHeapScan *) plan)->bitmapqualorig,
2417 : &context);
2418 6646 : context.paramids = bms_add_members(context.paramids, scan_params);
2419 6646 : break;
2420 :
2421 558 : case T_TidScan:
2422 558 : finalize_primnode((Node *) ((TidScan *) plan)->tidquals,
2423 : &context);
2424 558 : context.paramids = bms_add_members(context.paramids, scan_params);
2425 558 : break;
2426 :
2427 34 : case T_TidRangeScan:
2428 34 : finalize_primnode((Node *) ((TidRangeScan *) plan)->tidrangequals,
2429 : &context);
2430 34 : context.paramids = bms_add_members(context.paramids, scan_params);
2431 34 : break;
2432 :
2433 15988 : case T_SubqueryScan:
2434 : {
2435 15988 : SubqueryScan *sscan = (SubqueryScan *) plan;
2436 : RelOptInfo *rel;
2437 : Bitmapset *subquery_params;
2438 :
2439 : /* We must run finalize_plan on the subquery */
2440 15988 : rel = find_base_rel(root, sscan->scan.scanrelid);
2441 15988 : subquery_params = rel->subroot->outer_params;
2442 15988 : if (gather_param >= 0)
2443 24 : subquery_params = bms_add_member(bms_copy(subquery_params),
2444 : gather_param);
2445 15988 : finalize_plan(rel->subroot, sscan->subplan, gather_param,
2446 : subquery_params, NULL);
2447 :
2448 : /* Now we can add its extParams to the parent's params */
2449 31976 : context.paramids = bms_add_members(context.paramids,
2450 15988 : sscan->subplan->extParam);
2451 : /* We need scan_params too, though */
2452 15988 : context.paramids = bms_add_members(context.paramids,
2453 : scan_params);
2454 : }
2455 15988 : break;
2456 :
2457 20866 : case T_FunctionScan:
2458 : {
2459 20866 : FunctionScan *fscan = (FunctionScan *) plan;
2460 : ListCell *lc;
2461 :
2462 : /*
2463 : * Call finalize_primnode independently on each function
2464 : * expression, so that we can record which params are
2465 : * referenced in each, in order to decide which need
2466 : * re-evaluating during rescan.
2467 : */
2468 41756 : foreach(lc, fscan->functions)
2469 : {
2470 20890 : RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc);
2471 : finalize_primnode_context funccontext;
2472 :
2473 20890 : funccontext = context;
2474 20890 : funccontext.paramids = NULL;
2475 :
2476 20890 : finalize_primnode(rtfunc->funcexpr, &funccontext);
2477 :
2478 : /* remember results for execution */
2479 20890 : rtfunc->funcparams = funccontext.paramids;
2480 :
2481 : /* add the function's params to the overall set */
2482 20890 : context.paramids = bms_add_members(context.paramids,
2483 20890 : funccontext.paramids);
2484 : }
2485 :
2486 20866 : context.paramids = bms_add_members(context.paramids,
2487 : scan_params);
2488 : }
2489 20866 : break;
2490 :
2491 234 : case T_TableFuncScan:
2492 234 : finalize_primnode((Node *) ((TableFuncScan *) plan)->tablefunc,
2493 : &context);
2494 234 : context.paramids = bms_add_members(context.paramids, scan_params);
2495 234 : break;
2496 :
2497 5256 : case T_ValuesScan:
2498 5256 : finalize_primnode((Node *) ((ValuesScan *) plan)->values_lists,
2499 : &context);
2500 5256 : context.paramids = bms_add_members(context.paramids, scan_params);
2501 5256 : break;
2502 :
2503 3200 : case T_CteScan:
2504 : {
2505 : /*
2506 : * You might think we should add the node's cteParam to
2507 : * paramids, but we shouldn't because that param is just a
2508 : * linkage mechanism for multiple CteScan nodes for the same
2509 : * CTE; it is never used for changed-param signaling. What we
2510 : * have to do instead is to find the referenced CTE plan and
2511 : * incorporate its external paramids, so that the correct
2512 : * things will happen if the CTE references outer-level
2513 : * variables. See test cases for bug #4902. (We assume
2514 : * SS_finalize_plan was run on the CTE plan already.)
2515 : */
2516 3200 : int plan_id = ((CteScan *) plan)->ctePlanId;
2517 : Plan *cteplan;
2518 :
2519 : /* so, do this ... */
2520 3200 : if (plan_id < 1 || plan_id > list_length(root->glob->subplans))
2521 0 : elog(ERROR, "could not find plan for CteScan referencing plan ID %d",
2522 : plan_id);
2523 3200 : cteplan = (Plan *) list_nth(root->glob->subplans, plan_id - 1);
2524 3200 : context.paramids =
2525 3200 : bms_add_members(context.paramids, cteplan->extParam);
2526 :
2527 : #ifdef NOT_USED
2528 : /* ... but not this */
2529 : context.paramids =
2530 : bms_add_member(context.paramids,
2531 : ((CteScan *) plan)->cteParam);
2532 : #endif
2533 :
2534 3200 : context.paramids = bms_add_members(context.paramids,
2535 : scan_params);
2536 : }
2537 3200 : break;
2538 :
2539 800 : case T_WorkTableScan:
2540 800 : context.paramids =
2541 800 : bms_add_member(context.paramids,
2542 : ((WorkTableScan *) plan)->wtParam);
2543 800 : context.paramids = bms_add_members(context.paramids, scan_params);
2544 800 : break;
2545 :
2546 370 : case T_NamedTuplestoreScan:
2547 370 : context.paramids = bms_add_members(context.paramids, scan_params);
2548 370 : break;
2549 :
2550 760 : case T_ForeignScan:
2551 : {
2552 760 : ForeignScan *fscan = (ForeignScan *) plan;
2553 :
2554 760 : finalize_primnode((Node *) fscan->fdw_exprs,
2555 : &context);
2556 760 : finalize_primnode((Node *) fscan->fdw_recheck_quals,
2557 : &context);
2558 :
2559 : /* We assume fdw_scan_tlist cannot contain Params */
2560 760 : context.paramids = bms_add_members(context.paramids,
2561 : scan_params);
2562 : }
2563 760 : break;
2564 :
2565 0 : case T_CustomScan:
2566 : {
2567 0 : CustomScan *cscan = (CustomScan *) plan;
2568 : ListCell *lc;
2569 :
2570 0 : finalize_primnode((Node *) cscan->custom_exprs,
2571 : &context);
2572 : /* We assume custom_scan_tlist cannot contain Params */
2573 0 : context.paramids =
2574 0 : bms_add_members(context.paramids, scan_params);
2575 :
2576 : /* child nodes if any */
2577 0 : foreach(lc, cscan->custom_plans)
2578 : {
2579 0 : context.paramids =
2580 0 : bms_add_members(context.paramids,
2581 0 : finalize_plan(root,
2582 0 : (Plan *) lfirst(lc),
2583 : gather_param,
2584 : valid_params,
2585 : scan_params));
2586 : }
2587 : }
2588 0 : break;
2589 :
2590 89876 : case T_ModifyTable:
2591 : {
2592 89876 : ModifyTable *mtplan = (ModifyTable *) plan;
2593 :
2594 : /* Force descendant scan nodes to reference epqParam */
2595 89876 : locally_added_param = mtplan->epqParam;
2596 89876 : valid_params = bms_add_member(bms_copy(valid_params),
2597 : locally_added_param);
2598 89876 : scan_params = bms_add_member(bms_copy(scan_params),
2599 : locally_added_param);
2600 89876 : finalize_primnode((Node *) mtplan->returningLists,
2601 : &context);
2602 89876 : finalize_primnode((Node *) mtplan->onConflictSet,
2603 : &context);
2604 89876 : finalize_primnode((Node *) mtplan->onConflictWhere,
2605 : &context);
2606 : /* exclRelTlist contains only Vars, doesn't need examination */
2607 : }
2608 89876 : break;
2609 :
2610 9206 : case T_Append:
2611 : {
2612 31952 : foreach(l, ((Append *) plan)->appendplans)
2613 : {
2614 22746 : context.paramids =
2615 22746 : bms_add_members(context.paramids,
2616 22746 : finalize_plan(root,
2617 22746 : (Plan *) lfirst(l),
2618 : gather_param,
2619 : valid_params,
2620 : scan_params));
2621 : }
2622 : }
2623 9206 : break;
2624 :
2625 108 : case T_MergeAppend:
2626 : {
2627 456 : foreach(l, ((MergeAppend *) plan)->mergeplans)
2628 : {
2629 348 : context.paramids =
2630 348 : bms_add_members(context.paramids,
2631 348 : finalize_plan(root,
2632 348 : (Plan *) lfirst(l),
2633 : gather_param,
2634 : valid_params,
2635 : scan_params));
2636 : }
2637 : }
2638 108 : break;
2639 :
2640 82 : case T_BitmapAnd:
2641 : {
2642 246 : foreach(l, ((BitmapAnd *) plan)->bitmapplans)
2643 : {
2644 164 : context.paramids =
2645 164 : bms_add_members(context.paramids,
2646 164 : finalize_plan(root,
2647 164 : (Plan *) lfirst(l),
2648 : gather_param,
2649 : valid_params,
2650 : scan_params));
2651 : }
2652 : }
2653 82 : break;
2654 :
2655 130 : case T_BitmapOr:
2656 : {
2657 390 : foreach(l, ((BitmapOr *) plan)->bitmapplans)
2658 : {
2659 260 : context.paramids =
2660 260 : bms_add_members(context.paramids,
2661 260 : finalize_plan(root,
2662 260 : (Plan *) lfirst(l),
2663 : gather_param,
2664 : valid_params,
2665 : scan_params));
2666 : }
2667 : }
2668 130 : break;
2669 :
2670 60136 : case T_NestLoop:
2671 : {
2672 60136 : finalize_primnode((Node *) ((Join *) plan)->joinqual,
2673 : &context);
2674 : /* collect set of params that will be passed to right child */
2675 106070 : foreach(l, ((NestLoop *) plan)->nestParams)
2676 : {
2677 45934 : NestLoopParam *nlp = (NestLoopParam *) lfirst(l);
2678 :
2679 45934 : nestloop_params = bms_add_member(nestloop_params,
2680 : nlp->paramno);
2681 : }
2682 : }
2683 60136 : break;
2684 :
2685 2774 : case T_MergeJoin:
2686 2774 : finalize_primnode((Node *) ((Join *) plan)->joinqual,
2687 : &context);
2688 2774 : finalize_primnode((Node *) ((MergeJoin *) plan)->mergeclauses,
2689 : &context);
2690 2774 : break;
2691 :
2692 15922 : case T_HashJoin:
2693 15922 : finalize_primnode((Node *) ((Join *) plan)->joinqual,
2694 : &context);
2695 15922 : finalize_primnode((Node *) ((HashJoin *) plan)->hashclauses,
2696 : &context);
2697 15922 : break;
2698 :
2699 15922 : case T_Hash:
2700 15922 : finalize_primnode((Node *) ((Hash *) plan)->hashkeys,
2701 : &context);
2702 15922 : break;
2703 :
2704 2110 : case T_Limit:
2705 2110 : finalize_primnode(((Limit *) plan)->limitOffset,
2706 : &context);
2707 2110 : finalize_primnode(((Limit *) plan)->limitCount,
2708 : &context);
2709 2110 : break;
2710 :
2711 800 : case T_RecursiveUnion:
2712 : /* child nodes are allowed to reference wtParam */
2713 800 : locally_added_param = ((RecursiveUnion *) plan)->wtParam;
2714 800 : valid_params = bms_add_member(bms_copy(valid_params),
2715 : locally_added_param);
2716 : /* wtParam does *not* get added to scan_params */
2717 800 : break;
2718 :
2719 7490 : case T_LockRows:
2720 : /* Force descendant scan nodes to reference epqParam */
2721 7490 : locally_added_param = ((LockRows *) plan)->epqParam;
2722 7490 : valid_params = bms_add_member(bms_copy(valid_params),
2723 : locally_added_param);
2724 7490 : scan_params = bms_add_member(bms_copy(scan_params),
2725 : locally_added_param);
2726 7490 : break;
2727 :
2728 8712 : case T_Agg:
2729 : {
2730 8712 : Agg *agg = (Agg *) plan;
2731 :
2732 : /*
2733 : * AGG_HASHED plans need to know which Params are referenced
2734 : * in aggregate calls. Do a separate scan to identify them.
2735 : */
2736 8712 : if (agg->aggstrategy == AGG_HASHED)
2737 : {
2738 : finalize_primnode_context aggcontext;
2739 :
2740 1100 : aggcontext.root = root;
2741 1100 : aggcontext.paramids = NULL;
2742 1100 : finalize_agg_primnode((Node *) agg->plan.targetlist,
2743 : &aggcontext);
2744 1100 : finalize_agg_primnode((Node *) agg->plan.qual,
2745 : &aggcontext);
2746 1100 : agg->aggParams = aggcontext.paramids;
2747 : }
2748 : }
2749 8712 : break;
2750 :
2751 110 : case T_WindowAgg:
2752 110 : finalize_primnode(((WindowAgg *) plan)->startOffset,
2753 : &context);
2754 110 : finalize_primnode(((WindowAgg *) plan)->endOffset,
2755 : &context);
2756 110 : break;
2757 :
2758 920 : case T_Gather:
2759 : /* child nodes are allowed to reference rescan_param, if any */
2760 920 : locally_added_param = ((Gather *) plan)->rescan_param;
2761 920 : if (locally_added_param >= 0)
2762 : {
2763 920 : valid_params = bms_add_member(bms_copy(valid_params),
2764 : locally_added_param);
2765 :
2766 : /*
2767 : * We currently don't support nested Gathers. The issue so
2768 : * far as this function is concerned would be how to identify
2769 : * which child nodes depend on which Gather.
2770 : */
2771 : Assert(gather_param < 0);
2772 : /* Pass down rescan_param to child parallel-aware nodes */
2773 920 : gather_param = locally_added_param;
2774 : }
2775 : /* rescan_param does *not* get added to scan_params */
2776 920 : break;
2777 :
2778 318 : case T_GatherMerge:
2779 : /* child nodes are allowed to reference rescan_param, if any */
2780 318 : locally_added_param = ((GatherMerge *) plan)->rescan_param;
2781 318 : if (locally_added_param >= 0)
2782 : {
2783 318 : valid_params = bms_add_member(bms_copy(valid_params),
2784 : locally_added_param);
2785 :
2786 : /*
2787 : * We currently don't support nested Gathers. The issue so
2788 : * far as this function is concerned would be how to identify
2789 : * which child nodes depend on which Gather.
2790 : */
2791 : Assert(gather_param < 0);
2792 : /* Pass down rescan_param to child parallel-aware nodes */
2793 318 : gather_param = locally_added_param;
2794 : }
2795 : /* rescan_param does *not* get added to scan_params */
2796 318 : break;
2797 :
2798 1334 : case T_Memoize:
2799 1334 : finalize_primnode((Node *) ((Memoize *) plan)->param_exprs,
2800 : &context);
2801 1334 : break;
2802 :
2803 36164 : case T_ProjectSet:
2804 : case T_Material:
2805 : case T_Sort:
2806 : case T_IncrementalSort:
2807 : case T_Unique:
2808 : case T_SetOp:
2809 : case T_Group:
2810 : /* no node-type-specific fields need fixing */
2811 36164 : break;
2812 :
2813 0 : default:
2814 0 : elog(ERROR, "unrecognized node type: %d",
2815 : (int) nodeTag(plan));
2816 : }
2817 :
2818 : /* Process left and right child plans, if any */
2819 559868 : child_params = finalize_plan(root,
2820 559868 : plan->lefttree,
2821 : gather_param,
2822 : valid_params,
2823 : scan_params);
2824 559868 : context.paramids = bms_add_members(context.paramids, child_params);
2825 :
2826 559868 : if (nestloop_params)
2827 : {
2828 : /* right child can reference nestloop_params as well as valid_params */
2829 42348 : child_params = finalize_plan(root,
2830 42348 : plan->righttree,
2831 : gather_param,
2832 : bms_union(nestloop_params, valid_params),
2833 : scan_params);
2834 : /* ... and they don't count as parameters used at my level */
2835 42348 : child_params = bms_difference(child_params, nestloop_params);
2836 42348 : bms_free(nestloop_params);
2837 : }
2838 : else
2839 : {
2840 : /* easy case */
2841 517520 : child_params = finalize_plan(root,
2842 517520 : plan->righttree,
2843 : gather_param,
2844 : valid_params,
2845 : scan_params);
2846 : }
2847 559868 : context.paramids = bms_add_members(context.paramids, child_params);
2848 :
2849 : /*
2850 : * Any locally generated parameter doesn't count towards its generating
2851 : * plan node's external dependencies. (Note: if we changed valid_params
2852 : * and/or scan_params, we leak those bitmapsets; not worth the notational
2853 : * trouble to clean them up.)
2854 : */
2855 559868 : if (locally_added_param >= 0)
2856 : {
2857 99404 : context.paramids = bms_del_member(context.paramids,
2858 : locally_added_param);
2859 : }
2860 :
2861 : /* Now we have all the paramids referenced in this node and children */
2862 :
2863 559868 : if (!bms_is_subset(context.paramids, valid_params))
2864 0 : elog(ERROR, "plan should not reference subplan's variable");
2865 :
2866 : /*
2867 : * The plan node's allParam and extParam fields should include all its
2868 : * referenced paramids, plus contributions from any child initPlans.
2869 : * However, any setParams of the initPlans should not be present in the
2870 : * parent node's extParams, only in its allParams. (It's possible that
2871 : * some initPlans have extParams that are setParams of other initPlans.)
2872 : */
2873 :
2874 : /* allParam must include initplans' extParams and setParams */
2875 559868 : plan->allParam = bms_union(context.paramids, initExtParam);
2876 559868 : plan->allParam = bms_add_members(plan->allParam, initSetParam);
2877 : /* extParam must include any initplan extParams */
2878 559868 : plan->extParam = bms_union(context.paramids, initExtParam);
2879 : /* but not any initplan setParams */
2880 559868 : plan->extParam = bms_del_members(plan->extParam, initSetParam);
2881 :
2882 559868 : return plan->allParam;
2883 : }
2884 :
2885 : /*
2886 : * finalize_primnode: add IDs of all PARAM_EXEC params that appear (or will
2887 : * appear) in the given expression tree to the result set.
2888 : */
2889 : static bool
2890 9337590 : finalize_primnode(Node *node, finalize_primnode_context *context)
2891 : {
2892 9337590 : if (node == NULL)
2893 1163340 : return false;
2894 8174250 : if (IsA(node, Param))
2895 : {
2896 113140 : if (((Param *) node)->paramkind == PARAM_EXEC)
2897 : {
2898 109818 : int paramid = ((Param *) node)->paramid;
2899 :
2900 109818 : context->paramids = bms_add_member(context->paramids, paramid);
2901 : }
2902 113140 : return false; /* no more to do here */
2903 : }
2904 8061110 : else if (IsA(node, Aggref))
2905 : {
2906 : /*
2907 : * Check to see if the aggregate will be replaced by a Param
2908 : * referencing a subquery output during setrefs.c. If so, we must
2909 : * account for that Param here. (For various reasons, it's not
2910 : * convenient to perform that substitution earlier than setrefs.c, nor
2911 : * to perform this processing after setrefs.c. Thus we need a wart
2912 : * here.)
2913 : */
2914 12126 : Aggref *aggref = (Aggref *) node;
2915 : Param *aggparam;
2916 :
2917 12126 : aggparam = find_minmax_agg_replacement_param(context->root, aggref);
2918 12126 : if (aggparam != NULL)
2919 520 : context->paramids = bms_add_member(context->paramids,
2920 : aggparam->paramid);
2921 : /* Fall through to examine the agg's arguments */
2922 : }
2923 8048984 : else if (IsA(node, SubPlan))
2924 : {
2925 30538 : SubPlan *subplan = (SubPlan *) node;
2926 30538 : Plan *plan = planner_subplan_get_plan(context->root, subplan);
2927 : ListCell *lc;
2928 : Bitmapset *subparamids;
2929 :
2930 : /* Recurse into the testexpr, but not into the Plan */
2931 30538 : finalize_primnode(subplan->testexpr, context);
2932 :
2933 : /*
2934 : * Remove any param IDs of output parameters of the subplan that were
2935 : * referenced in the testexpr. These are not interesting for
2936 : * parameter change signaling since we always re-evaluate the subplan.
2937 : * Note that this wouldn't work too well if there might be uses of the
2938 : * same param IDs elsewhere in the plan, but that can't happen because
2939 : * generate_new_exec_param never tries to merge params.
2940 : */
2941 33454 : foreach(lc, subplan->paramIds)
2942 : {
2943 2916 : context->paramids = bms_del_member(context->paramids,
2944 : lfirst_int(lc));
2945 : }
2946 :
2947 : /* Also examine args list */
2948 30538 : finalize_primnode((Node *) subplan->args, context);
2949 :
2950 : /*
2951 : * Add params needed by the subplan to paramids, but excluding those
2952 : * we will pass down to it. (We assume SS_finalize_plan was run on
2953 : * the subplan already.)
2954 : */
2955 30538 : subparamids = bms_copy(plan->extParam);
2956 74610 : foreach(lc, subplan->parParam)
2957 : {
2958 44072 : subparamids = bms_del_member(subparamids, lfirst_int(lc));
2959 : }
2960 30538 : context->paramids = bms_join(context->paramids, subparamids);
2961 :
2962 30538 : return false; /* no more to do here */
2963 : }
2964 8030572 : return expression_tree_walker(node, finalize_primnode,
2965 : (void *) context);
2966 : }
2967 :
2968 : /*
2969 : * finalize_agg_primnode: find all Aggref nodes in the given expression tree,
2970 : * and add IDs of all PARAM_EXEC params appearing within their aggregated
2971 : * arguments to the result set.
2972 : */
2973 : static bool
2974 9456 : finalize_agg_primnode(Node *node, finalize_primnode_context *context)
2975 : {
2976 9456 : if (node == NULL)
2977 1038 : return false;
2978 8418 : if (IsA(node, Aggref))
2979 : {
2980 1120 : Aggref *agg = (Aggref *) node;
2981 :
2982 : /* we should not consider the direct arguments, if any */
2983 1120 : finalize_primnode((Node *) agg->args, context);
2984 1120 : finalize_primnode((Node *) agg->aggfilter, context);
2985 1120 : return false; /* there can't be any Aggrefs below here */
2986 : }
2987 7298 : return expression_tree_walker(node, finalize_agg_primnode,
2988 : (void *) context);
2989 : }
2990 :
2991 : /*
2992 : * SS_make_initplan_output_param - make a Param for an initPlan's output
2993 : *
2994 : * The plan is expected to return a scalar value of the given type/collation.
2995 : *
2996 : * Note that in some cases the initplan may not ever appear in the finished
2997 : * plan tree. If that happens, we'll have wasted a PARAM_EXEC slot, which
2998 : * is no big deal.
2999 : */
3000 : Param *
3001 422 : SS_make_initplan_output_param(PlannerInfo *root,
3002 : Oid resulttype, int32 resulttypmod,
3003 : Oid resultcollation)
3004 : {
3005 422 : return generate_new_exec_param(root, resulttype,
3006 : resulttypmod, resultcollation);
3007 : }
3008 :
3009 : /*
3010 : * SS_make_initplan_from_plan - given a plan tree, make it an InitPlan
3011 : *
3012 : * We build an EXPR_SUBLINK SubPlan node and put it into the initplan
3013 : * list for the outer query level. A Param that represents the initplan's
3014 : * output has already been assigned using SS_make_initplan_output_param.
3015 : */
3016 : void
3017 376 : SS_make_initplan_from_plan(PlannerInfo *root,
3018 : PlannerInfo *subroot, Plan *plan,
3019 : Param *prm)
3020 : {
3021 : SubPlan *node;
3022 :
3023 : /*
3024 : * Add the subplan and its PlannerInfo, as well as a dummy path entry, to
3025 : * the global lists. Ideally we'd save a real path, but right now our
3026 : * sole caller doesn't build a path that exactly matches the plan. Since
3027 : * we're not currently going to need the path for an initplan, it's not
3028 : * worth requiring construction of such a path.
3029 : */
3030 376 : root->glob->subplans = lappend(root->glob->subplans, plan);
3031 376 : root->glob->subpaths = lappend(root->glob->subpaths, NULL);
3032 376 : root->glob->subroots = lappend(root->glob->subroots, subroot);
3033 :
3034 : /*
3035 : * Create a SubPlan node and add it to the outer list of InitPlans. Note
3036 : * it has to appear after any other InitPlans it might depend on (see
3037 : * comments in ExecReScan).
3038 : */
3039 376 : node = makeNode(SubPlan);
3040 376 : node->subLinkType = EXPR_SUBLINK;
3041 376 : node->plan_id = list_length(root->glob->subplans);
3042 376 : node->plan_name = psprintf("InitPlan %d", node->plan_id);
3043 376 : get_first_col_type(plan, &node->firstColType, &node->firstColTypmod,
3044 : &node->firstColCollation);
3045 376 : node->parallel_safe = plan->parallel_safe;
3046 376 : node->setParam = list_make1_int(prm->paramid);
3047 :
3048 376 : root->init_plans = lappend(root->init_plans, node);
3049 :
3050 : /*
3051 : * The node can't have any inputs (since it's an initplan), so the
3052 : * parParam and args lists remain empty.
3053 : */
3054 :
3055 : /* Set costs of SubPlan using info from the plan tree */
3056 376 : cost_subplan(subroot, node, plan);
3057 376 : }
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