Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * var.c
4 : * Var node manipulation routines
5 : *
6 : * Note: for most purposes, PlaceHolderVar is considered a Var too,
7 : * even if its contained expression is variable-free. Also, CurrentOfExpr
8 : * is treated as a Var for purposes of determining whether an expression
9 : * contains variables.
10 : *
11 : *
12 : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
13 : * Portions Copyright (c) 1994, Regents of the University of California
14 : *
15 : *
16 : * IDENTIFICATION
17 : * src/backend/optimizer/util/var.c
18 : *
19 : *-------------------------------------------------------------------------
20 : */
21 : #include "postgres.h"
22 :
23 : #include "access/sysattr.h"
24 : #include "nodes/nodeFuncs.h"
25 : #include "optimizer/clauses.h"
26 : #include "optimizer/optimizer.h"
27 : #include "optimizer/placeholder.h"
28 : #include "optimizer/prep.h"
29 : #include "parser/parsetree.h"
30 : #include "rewrite/rewriteManip.h"
31 :
32 :
33 : typedef struct
34 : {
35 : Relids varnos;
36 : PlannerInfo *root;
37 : int sublevels_up;
38 : } pull_varnos_context;
39 :
40 : typedef struct
41 : {
42 : Bitmapset *varattnos;
43 : Index varno;
44 : } pull_varattnos_context;
45 :
46 : typedef struct
47 : {
48 : List *vars;
49 : int sublevels_up;
50 : } pull_vars_context;
51 :
52 : typedef struct
53 : {
54 : int var_location;
55 : int sublevels_up;
56 : } locate_var_of_level_context;
57 :
58 : typedef struct
59 : {
60 : List *varlist;
61 : int flags;
62 : } pull_var_clause_context;
63 :
64 : typedef struct
65 : {
66 : PlannerInfo *root; /* could be NULL! */
67 : Query *query; /* outer Query */
68 : int sublevels_up;
69 : bool possible_sublink; /* could aliases include a SubLink? */
70 : bool inserted_sublink; /* have we inserted a SubLink? */
71 : } flatten_join_alias_vars_context;
72 :
73 : static bool pull_varnos_walker(Node *node,
74 : pull_varnos_context *context);
75 : static bool pull_varattnos_walker(Node *node, pull_varattnos_context *context);
76 : static bool pull_vars_walker(Node *node, pull_vars_context *context);
77 : static bool contain_var_clause_walker(Node *node, void *context);
78 : static bool contain_vars_of_level_walker(Node *node, int *sublevels_up);
79 : static bool contain_vars_returning_old_or_new_walker(Node *node, void *context);
80 : static bool locate_var_of_level_walker(Node *node,
81 : locate_var_of_level_context *context);
82 : static bool pull_var_clause_walker(Node *node,
83 : pull_var_clause_context *context);
84 : static Node *flatten_join_alias_vars_mutator(Node *node,
85 : flatten_join_alias_vars_context *context);
86 : static Node *flatten_group_exprs_mutator(Node *node,
87 : flatten_join_alias_vars_context *context);
88 : static Node *mark_nullable_by_grouping(PlannerInfo *root, Node *newnode,
89 : Var *oldvar);
90 : static Node *add_nullingrels_if_needed(PlannerInfo *root, Node *newnode,
91 : Var *oldvar);
92 : static bool is_standard_join_alias_expression(Node *newnode, Var *oldvar);
93 : static void adjust_standard_join_alias_expression(Node *newnode, Var *oldvar);
94 : static Relids alias_relid_set(Query *query, Relids relids);
95 :
96 :
97 : /*
98 : * pull_varnos
99 : * Create a set of all the distinct varnos present in a parsetree.
100 : * Only varnos that reference level-zero rtable entries are considered.
101 : *
102 : * The result includes outer-join relids mentioned in Var.varnullingrels and
103 : * PlaceHolderVar.phnullingrels fields in the parsetree.
104 : *
105 : * "root" can be passed as NULL if it is not necessary to process
106 : * PlaceHolderVars.
107 : *
108 : * NOTE: this is used on not-yet-planned expressions. It may therefore find
109 : * bare SubLinks, and if so it needs to recurse into them to look for uplevel
110 : * references to the desired rtable level! But when we find a completed
111 : * SubPlan, we only need to look at the parameters passed to the subplan.
112 : */
113 : Relids
114 3248878 : pull_varnos(PlannerInfo *root, Node *node)
115 : {
116 : pull_varnos_context context;
117 :
118 3248878 : context.varnos = NULL;
119 3248878 : context.root = root;
120 3248878 : context.sublevels_up = 0;
121 :
122 : /*
123 : * Must be prepared to start with a Query or a bare expression tree; if
124 : * it's a Query, we don't want to increment sublevels_up.
125 : */
126 3248878 : query_or_expression_tree_walker(node,
127 : pull_varnos_walker,
128 : &context,
129 : 0);
130 :
131 3248878 : return context.varnos;
132 : }
133 :
134 : /*
135 : * pull_varnos_of_level
136 : * Create a set of all the distinct varnos present in a parsetree.
137 : * Only Vars of the specified level are considered.
138 : */
139 : Relids
140 9282 : pull_varnos_of_level(PlannerInfo *root, Node *node, int levelsup)
141 : {
142 : pull_varnos_context context;
143 :
144 9282 : context.varnos = NULL;
145 9282 : context.root = root;
146 9282 : context.sublevels_up = levelsup;
147 :
148 : /*
149 : * Must be prepared to start with a Query or a bare expression tree; if
150 : * it's a Query, we don't want to increment sublevels_up.
151 : */
152 9282 : query_or_expression_tree_walker(node,
153 : pull_varnos_walker,
154 : &context,
155 : 0);
156 :
157 9282 : return context.varnos;
158 : }
159 :
160 : static bool
161 5697150 : pull_varnos_walker(Node *node, pull_varnos_context *context)
162 : {
163 5697150 : if (node == NULL)
164 219030 : return false;
165 5478120 : if (IsA(node, Var))
166 : {
167 2674152 : Var *var = (Var *) node;
168 :
169 2674152 : if (var->varlevelsup == context->sublevels_up)
170 : {
171 2661886 : context->varnos = bms_add_member(context->varnos, var->varno);
172 2661886 : context->varnos = bms_add_members(context->varnos,
173 2661886 : var->varnullingrels);
174 : }
175 2674152 : return false;
176 : }
177 2803968 : if (IsA(node, CurrentOfExpr))
178 : {
179 800 : CurrentOfExpr *cexpr = (CurrentOfExpr *) node;
180 :
181 800 : if (context->sublevels_up == 0)
182 800 : context->varnos = bms_add_member(context->varnos, cexpr->cvarno);
183 800 : return false;
184 : }
185 2803168 : if (IsA(node, PlaceHolderVar))
186 : {
187 8996 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
188 :
189 : /*
190 : * If a PlaceHolderVar is not of the target query level, ignore it,
191 : * instead recursing into its expression to see if it contains any
192 : * vars that are of the target level. We'll also do that when the
193 : * caller doesn't pass a "root" pointer. (We probably shouldn't see
194 : * PlaceHolderVars at all in such cases, but if we do, this is a
195 : * reasonable behavior.)
196 : */
197 8996 : if (phv->phlevelsup == context->sublevels_up &&
198 8996 : context->root != NULL)
199 : {
200 : /*
201 : * Ideally, the PHV's contribution to context->varnos is its
202 : * ph_eval_at set. However, this code can be invoked before
203 : * that's been computed. If we cannot find a PlaceHolderInfo,
204 : * fall back to the conservative assumption that the PHV will be
205 : * evaluated at its syntactic level (phv->phrels).
206 : *
207 : * Another problem is that a PlaceHolderVar can appear in quals or
208 : * tlists that have been translated for use in a child appendrel.
209 : * Typically such a PHV is a parameter expression sourced by some
210 : * other relation, so that the translation from parent appendrel
211 : * to child doesn't change its phrels, and we should still take
212 : * ph_eval_at at face value. But in corner cases, the PHV's
213 : * original phrels can include the parent appendrel itself, in
214 : * which case the translated PHV will have the child appendrel in
215 : * phrels, and we must translate ph_eval_at to match.
216 : */
217 8996 : PlaceHolderInfo *phinfo = NULL;
218 :
219 8996 : if (phv->phlevelsup == 0)
220 : {
221 8900 : if (phv->phid < context->root->placeholder_array_size)
222 7390 : phinfo = context->root->placeholder_array[phv->phid];
223 : }
224 8996 : if (phinfo == NULL)
225 : {
226 : /* No PlaceHolderInfo yet, use phrels */
227 1618 : context->varnos = bms_add_members(context->varnos,
228 1618 : phv->phrels);
229 : }
230 7378 : else if (bms_equal(phv->phrels, phinfo->ph_var->phrels))
231 : {
232 : /* Normal case: use ph_eval_at */
233 6484 : context->varnos = bms_add_members(context->varnos,
234 6484 : phinfo->ph_eval_at);
235 : }
236 : else
237 : {
238 : /* Translated PlaceHolderVar: translate ph_eval_at to match */
239 : Relids newevalat,
240 : delta;
241 :
242 : /* remove what was removed from phv->phrels ... */
243 894 : delta = bms_difference(phinfo->ph_var->phrels, phv->phrels);
244 894 : newevalat = bms_difference(phinfo->ph_eval_at, delta);
245 : /* ... then if that was in fact part of ph_eval_at ... */
246 894 : if (!bms_equal(newevalat, phinfo->ph_eval_at))
247 : {
248 : /* ... add what was added */
249 600 : delta = bms_difference(phv->phrels, phinfo->ph_var->phrels);
250 600 : newevalat = bms_join(newevalat, delta);
251 : }
252 894 : context->varnos = bms_join(context->varnos,
253 : newevalat);
254 : }
255 :
256 : /*
257 : * In all three cases, include phnullingrels in the result. We
258 : * don't worry about possibly needing to translate it, because
259 : * appendrels only translate varnos of baserels, not outer joins.
260 : */
261 17992 : context->varnos = bms_add_members(context->varnos,
262 8996 : phv->phnullingrels);
263 8996 : return false; /* don't recurse into expression */
264 : }
265 : }
266 2794172 : else if (IsA(node, Query))
267 : {
268 : /* Recurse into RTE subquery or not-yet-planned sublink subquery */
269 : bool result;
270 :
271 7116 : context->sublevels_up++;
272 7116 : result = query_tree_walker((Query *) node, pull_varnos_walker,
273 : context, 0);
274 7116 : context->sublevels_up--;
275 7116 : return result;
276 : }
277 2787056 : return expression_tree_walker(node, pull_varnos_walker, context);
278 : }
279 :
280 :
281 : /*
282 : * pull_varattnos
283 : * Find all the distinct attribute numbers present in an expression tree,
284 : * and add them to the initial contents of *varattnos.
285 : * Only Vars of the given varno and rtable level zero are considered.
286 : *
287 : * Attribute numbers are offset by FirstLowInvalidHeapAttributeNumber so that
288 : * we can include system attributes (e.g., OID) in the bitmap representation.
289 : *
290 : * Currently, this does not support unplanned subqueries; that is not needed
291 : * for current uses. It will handle already-planned SubPlan nodes, though,
292 : * looking into only the "testexpr" and the "args" list. (The subplan cannot
293 : * contain any other references to Vars of the current level.)
294 : */
295 : void
296 1861542 : pull_varattnos(Node *node, Index varno, Bitmapset **varattnos)
297 : {
298 : pull_varattnos_context context;
299 :
300 1861542 : context.varattnos = *varattnos;
301 1861542 : context.varno = varno;
302 :
303 1861542 : (void) pull_varattnos_walker(node, &context);
304 :
305 1861542 : *varattnos = context.varattnos;
306 1861542 : }
307 :
308 : static bool
309 6338678 : pull_varattnos_walker(Node *node, pull_varattnos_context *context)
310 : {
311 6338678 : if (node == NULL)
312 78528 : return false;
313 6260150 : if (IsA(node, Var))
314 : {
315 3629364 : Var *var = (Var *) node;
316 :
317 3629364 : if (var->varno == context->varno && var->varlevelsup == 0)
318 3628910 : context->varattnos =
319 3628910 : bms_add_member(context->varattnos,
320 3628910 : var->varattno - FirstLowInvalidHeapAttributeNumber);
321 3629364 : return false;
322 : }
323 :
324 : /* Should not find an unplanned subquery */
325 : Assert(!IsA(node, Query));
326 :
327 2630786 : return expression_tree_walker(node, pull_varattnos_walker, context);
328 : }
329 :
330 :
331 : /*
332 : * pull_vars_of_level
333 : * Create a list of all Vars (and PlaceHolderVars) referencing the
334 : * specified query level in the given parsetree.
335 : *
336 : * Caution: the Vars are not copied, only linked into the list.
337 : */
338 : List *
339 9362 : pull_vars_of_level(Node *node, int levelsup)
340 : {
341 : pull_vars_context context;
342 :
343 9362 : context.vars = NIL;
344 9362 : context.sublevels_up = levelsup;
345 :
346 : /*
347 : * Must be prepared to start with a Query or a bare expression tree; if
348 : * it's a Query, we don't want to increment sublevels_up.
349 : */
350 9362 : query_or_expression_tree_walker(node,
351 : pull_vars_walker,
352 : &context,
353 : 0);
354 :
355 9362 : return context.vars;
356 : }
357 :
358 : static bool
359 109516 : pull_vars_walker(Node *node, pull_vars_context *context)
360 : {
361 109516 : if (node == NULL)
362 14240 : return false;
363 95276 : if (IsA(node, Var))
364 : {
365 13280 : Var *var = (Var *) node;
366 :
367 13280 : if (var->varlevelsup == context->sublevels_up)
368 10050 : context->vars = lappend(context->vars, var);
369 13280 : return false;
370 : }
371 81996 : if (IsA(node, PlaceHolderVar))
372 : {
373 138 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
374 :
375 138 : if (phv->phlevelsup == context->sublevels_up)
376 138 : context->vars = lappend(context->vars, phv);
377 : /* we don't want to look into the contained expression */
378 138 : return false;
379 : }
380 81858 : if (IsA(node, Query))
381 : {
382 : /* Recurse into RTE subquery or not-yet-planned sublink subquery */
383 : bool result;
384 :
385 348 : context->sublevels_up++;
386 348 : result = query_tree_walker((Query *) node, pull_vars_walker,
387 : context, 0);
388 348 : context->sublevels_up--;
389 348 : return result;
390 : }
391 81510 : return expression_tree_walker(node, pull_vars_walker, context);
392 : }
393 :
394 :
395 : /*
396 : * contain_var_clause
397 : * Recursively scan a clause to discover whether it contains any Var nodes
398 : * (of the current query level).
399 : *
400 : * Returns true if any varnode found.
401 : *
402 : * Does not examine subqueries, therefore must only be used after reduction
403 : * of sublinks to subplans!
404 : */
405 : bool
406 20634 : contain_var_clause(Node *node)
407 : {
408 20634 : return contain_var_clause_walker(node, NULL);
409 : }
410 :
411 : static bool
412 26984 : contain_var_clause_walker(Node *node, void *context)
413 : {
414 26984 : if (node == NULL)
415 126 : return false;
416 26858 : if (IsA(node, Var))
417 : {
418 2264 : if (((Var *) node)->varlevelsup == 0)
419 2264 : return true; /* abort the tree traversal and return true */
420 0 : return false;
421 : }
422 24594 : if (IsA(node, CurrentOfExpr))
423 0 : return true;
424 24594 : if (IsA(node, PlaceHolderVar))
425 : {
426 12 : if (((PlaceHolderVar *) node)->phlevelsup == 0)
427 12 : return true; /* abort the tree traversal and return true */
428 : /* else fall through to check the contained expr */
429 : }
430 24582 : return expression_tree_walker(node, contain_var_clause_walker, context);
431 : }
432 :
433 :
434 : /*
435 : * contain_vars_of_level
436 : * Recursively scan a clause to discover whether it contains any Var nodes
437 : * of the specified query level.
438 : *
439 : * Returns true if any such Var found.
440 : *
441 : * Will recurse into sublinks. Also, may be invoked directly on a Query.
442 : */
443 : bool
444 167396 : contain_vars_of_level(Node *node, int levelsup)
445 : {
446 167396 : int sublevels_up = levelsup;
447 :
448 167396 : return query_or_expression_tree_walker(node,
449 : contain_vars_of_level_walker,
450 : &sublevels_up,
451 : 0);
452 : }
453 :
454 : static bool
455 565980 : contain_vars_of_level_walker(Node *node, int *sublevels_up)
456 : {
457 565980 : if (node == NULL)
458 99148 : return false;
459 466832 : if (IsA(node, Var))
460 : {
461 69638 : if (((Var *) node)->varlevelsup == *sublevels_up)
462 43156 : return true; /* abort tree traversal and return true */
463 26482 : return false;
464 : }
465 397194 : if (IsA(node, CurrentOfExpr))
466 : {
467 184 : if (*sublevels_up == 0)
468 184 : return true;
469 0 : return false;
470 : }
471 397010 : if (IsA(node, PlaceHolderVar))
472 : {
473 78 : if (((PlaceHolderVar *) node)->phlevelsup == *sublevels_up)
474 78 : return true; /* abort the tree traversal and return true */
475 : /* else fall through to check the contained expr */
476 : }
477 396932 : if (IsA(node, Query))
478 : {
479 : /* Recurse into subselects */
480 : bool result;
481 :
482 744 : (*sublevels_up)++;
483 744 : result = query_tree_walker((Query *) node,
484 : contain_vars_of_level_walker,
485 : sublevels_up,
486 : 0);
487 744 : (*sublevels_up)--;
488 744 : return result;
489 : }
490 396188 : return expression_tree_walker(node,
491 : contain_vars_of_level_walker,
492 : sublevels_up);
493 : }
494 :
495 :
496 : /*
497 : * contain_vars_returning_old_or_new
498 : * Recursively scan a clause to discover whether it contains any Var nodes
499 : * (of the current query level) whose varreturningtype is VAR_RETURNING_OLD
500 : * or VAR_RETURNING_NEW.
501 : *
502 : * Returns true if any found.
503 : *
504 : * Any ReturningExprs are also detected --- if an OLD/NEW Var was rewritten,
505 : * we still regard this as a clause that returns OLD/NEW values.
506 : *
507 : * Does not examine subqueries, therefore must only be used after reduction
508 : * of sublinks to subplans!
509 : */
510 : bool
511 386 : contain_vars_returning_old_or_new(Node *node)
512 : {
513 386 : return contain_vars_returning_old_or_new_walker(node, NULL);
514 : }
515 :
516 : static bool
517 1210 : contain_vars_returning_old_or_new_walker(Node *node, void *context)
518 : {
519 1210 : if (node == NULL)
520 270 : return false;
521 940 : if (IsA(node, Var))
522 : {
523 402 : if (((Var *) node)->varlevelsup == 0 &&
524 402 : ((Var *) node)->varreturningtype != VAR_RETURNING_DEFAULT)
525 14 : return true; /* abort the tree traversal and return true */
526 388 : return false;
527 : }
528 538 : if (IsA(node, ReturningExpr))
529 : {
530 0 : if (((ReturningExpr *) node)->retlevelsup == 0)
531 0 : return true; /* abort the tree traversal and return true */
532 0 : return false;
533 : }
534 538 : return expression_tree_walker(node, contain_vars_returning_old_or_new_walker,
535 : context);
536 : }
537 :
538 :
539 : /*
540 : * locate_var_of_level
541 : * Find the parse location of any Var of the specified query level.
542 : *
543 : * Returns -1 if no such Var is in the querytree, or if they all have
544 : * unknown parse location. (The former case is probably caller error,
545 : * but we don't bother to distinguish it from the latter case.)
546 : *
547 : * Will recurse into sublinks. Also, may be invoked directly on a Query.
548 : *
549 : * Note: it might seem appropriate to merge this functionality into
550 : * contain_vars_of_level, but that would complicate that function's API.
551 : * Currently, the only uses of this function are for error reporting,
552 : * and so shaving cycles probably isn't very important.
553 : */
554 : int
555 12 : locate_var_of_level(Node *node, int levelsup)
556 : {
557 : locate_var_of_level_context context;
558 :
559 12 : context.var_location = -1; /* in case we find nothing */
560 12 : context.sublevels_up = levelsup;
561 :
562 12 : (void) query_or_expression_tree_walker(node,
563 : locate_var_of_level_walker,
564 : &context,
565 : 0);
566 :
567 12 : return context.var_location;
568 : }
569 :
570 : static bool
571 30 : locate_var_of_level_walker(Node *node,
572 : locate_var_of_level_context *context)
573 : {
574 30 : if (node == NULL)
575 0 : return false;
576 30 : if (IsA(node, Var))
577 : {
578 12 : Var *var = (Var *) node;
579 :
580 12 : if (var->varlevelsup == context->sublevels_up &&
581 12 : var->location >= 0)
582 : {
583 12 : context->var_location = var->location;
584 12 : return true; /* abort tree traversal and return true */
585 : }
586 0 : return false;
587 : }
588 18 : if (IsA(node, CurrentOfExpr))
589 : {
590 : /* since CurrentOfExpr doesn't carry location, nothing we can do */
591 0 : return false;
592 : }
593 : /* No extra code needed for PlaceHolderVar; just look in contained expr */
594 18 : if (IsA(node, Query))
595 : {
596 : /* Recurse into subselects */
597 : bool result;
598 :
599 0 : context->sublevels_up++;
600 0 : result = query_tree_walker((Query *) node,
601 : locate_var_of_level_walker,
602 : context,
603 : 0);
604 0 : context->sublevels_up--;
605 0 : return result;
606 : }
607 18 : return expression_tree_walker(node,
608 : locate_var_of_level_walker,
609 : context);
610 : }
611 :
612 :
613 : /*
614 : * pull_var_clause
615 : * Recursively pulls all Var nodes from an expression clause.
616 : *
617 : * Aggrefs are handled according to these bits in 'flags':
618 : * PVC_INCLUDE_AGGREGATES include Aggrefs in output list
619 : * PVC_RECURSE_AGGREGATES recurse into Aggref arguments
620 : * neither flag throw error if Aggref found
621 : * Vars within an Aggref's expression are included in the result only
622 : * when PVC_RECURSE_AGGREGATES is specified.
623 : *
624 : * WindowFuncs are handled according to these bits in 'flags':
625 : * PVC_INCLUDE_WINDOWFUNCS include WindowFuncs in output list
626 : * PVC_RECURSE_WINDOWFUNCS recurse into WindowFunc arguments
627 : * neither flag throw error if WindowFunc found
628 : * Vars within a WindowFunc's expression are included in the result only
629 : * when PVC_RECURSE_WINDOWFUNCS is specified.
630 : *
631 : * PlaceHolderVars are handled according to these bits in 'flags':
632 : * PVC_INCLUDE_PLACEHOLDERS include PlaceHolderVars in output list
633 : * PVC_RECURSE_PLACEHOLDERS recurse into PlaceHolderVar arguments
634 : * neither flag throw error if PlaceHolderVar found
635 : * Vars within a PHV's expression are included in the result only
636 : * when PVC_RECURSE_PLACEHOLDERS is specified.
637 : *
638 : * GroupingFuncs are treated exactly like Aggrefs, and so do not need
639 : * their own flag bits.
640 : *
641 : * CurrentOfExpr nodes are ignored in all cases.
642 : *
643 : * Upper-level vars (with varlevelsup > 0) should not be seen here,
644 : * likewise for upper-level Aggrefs and PlaceHolderVars.
645 : *
646 : * Returns list of nodes found. Note the nodes themselves are not
647 : * copied, only referenced.
648 : *
649 : * Does not examine subqueries, therefore must only be used after reduction
650 : * of sublinks to subplans!
651 : */
652 : List *
653 772268 : pull_var_clause(Node *node, int flags)
654 : {
655 : pull_var_clause_context context;
656 :
657 : /* Assert that caller has not specified inconsistent flags */
658 : Assert((flags & (PVC_INCLUDE_AGGREGATES | PVC_RECURSE_AGGREGATES))
659 : != (PVC_INCLUDE_AGGREGATES | PVC_RECURSE_AGGREGATES));
660 : Assert((flags & (PVC_INCLUDE_WINDOWFUNCS | PVC_RECURSE_WINDOWFUNCS))
661 : != (PVC_INCLUDE_WINDOWFUNCS | PVC_RECURSE_WINDOWFUNCS));
662 : Assert((flags & (PVC_INCLUDE_PLACEHOLDERS | PVC_RECURSE_PLACEHOLDERS))
663 : != (PVC_INCLUDE_PLACEHOLDERS | PVC_RECURSE_PLACEHOLDERS));
664 :
665 772268 : context.varlist = NIL;
666 772268 : context.flags = flags;
667 :
668 772268 : pull_var_clause_walker(node, &context);
669 772268 : return context.varlist;
670 : }
671 :
672 : static bool
673 4673112 : pull_var_clause_walker(Node *node, pull_var_clause_context *context)
674 : {
675 4673112 : if (node == NULL)
676 187178 : return false;
677 4485934 : if (IsA(node, Var))
678 : {
679 1755160 : if (((Var *) node)->varlevelsup != 0)
680 0 : elog(ERROR, "Upper-level Var found where not expected");
681 1755160 : context->varlist = lappend(context->varlist, node);
682 1755160 : return false;
683 : }
684 2730774 : else if (IsA(node, Aggref))
685 : {
686 92624 : if (((Aggref *) node)->agglevelsup != 0)
687 0 : elog(ERROR, "Upper-level Aggref found where not expected");
688 92624 : if (context->flags & PVC_INCLUDE_AGGREGATES)
689 : {
690 4808 : context->varlist = lappend(context->varlist, node);
691 : /* we do NOT descend into the contained expression */
692 4808 : return false;
693 : }
694 87816 : else if (context->flags & PVC_RECURSE_AGGREGATES)
695 : {
696 : /* fall through to recurse into the aggregate's arguments */
697 : }
698 : else
699 0 : elog(ERROR, "Aggref found where not expected");
700 : }
701 2638150 : else if (IsA(node, GroupingFunc))
702 : {
703 646 : if (((GroupingFunc *) node)->agglevelsup != 0)
704 0 : elog(ERROR, "Upper-level GROUPING found where not expected");
705 646 : if (context->flags & PVC_INCLUDE_AGGREGATES)
706 : {
707 4 : context->varlist = lappend(context->varlist, node);
708 : /* we do NOT descend into the contained expression */
709 4 : return false;
710 : }
711 642 : else if (context->flags & PVC_RECURSE_AGGREGATES)
712 : {
713 : /* fall through to recurse into the GroupingFunc's arguments */
714 : }
715 : else
716 0 : elog(ERROR, "GROUPING found where not expected");
717 : }
718 2637504 : else if (IsA(node, WindowFunc))
719 : {
720 : /* WindowFuncs have no levelsup field to check ... */
721 6676 : if (context->flags & PVC_INCLUDE_WINDOWFUNCS)
722 : {
723 12 : context->varlist = lappend(context->varlist, node);
724 : /* we do NOT descend into the contained expressions */
725 12 : return false;
726 : }
727 6664 : else if (context->flags & PVC_RECURSE_WINDOWFUNCS)
728 : {
729 : /* fall through to recurse into the windowfunc's arguments */
730 : }
731 : else
732 0 : elog(ERROR, "WindowFunc found where not expected");
733 : }
734 2630828 : else if (IsA(node, PlaceHolderVar))
735 : {
736 6472 : if (((PlaceHolderVar *) node)->phlevelsup != 0)
737 0 : elog(ERROR, "Upper-level PlaceHolderVar found where not expected");
738 6472 : if (context->flags & PVC_INCLUDE_PLACEHOLDERS)
739 : {
740 4824 : context->varlist = lappend(context->varlist, node);
741 : /* we do NOT descend into the contained expression */
742 4824 : return false;
743 : }
744 1648 : else if (context->flags & PVC_RECURSE_PLACEHOLDERS)
745 : {
746 : /* fall through to recurse into the placeholder's expression */
747 : }
748 : else
749 0 : elog(ERROR, "PlaceHolderVar found where not expected");
750 : }
751 2721126 : return expression_tree_walker(node, pull_var_clause_walker, context);
752 : }
753 :
754 :
755 : /*
756 : * flatten_join_alias_vars
757 : * Replace Vars that reference JOIN outputs with references to the original
758 : * relation variables instead. This allows quals involving such vars to be
759 : * pushed down. Whole-row Vars that reference JOIN relations are expanded
760 : * into RowExpr constructs that name the individual output Vars. This
761 : * is necessary since we will not scan the JOIN as a base relation, which
762 : * is the only way that the executor can directly handle whole-row Vars.
763 : *
764 : * This also adjusts relid sets found in some expression node types to
765 : * substitute the contained base+OJ rels for any join relid.
766 : *
767 : * If a JOIN contains sub-selects that have been flattened, its join alias
768 : * entries might now be arbitrary expressions, not just Vars. This affects
769 : * this function in two important ways. First, we might find ourselves
770 : * inserting SubLink expressions into subqueries, and we must make sure that
771 : * their Query.hasSubLinks fields get set to true if so. If there are any
772 : * SubLinks in the join alias lists, the outer Query should already have
773 : * hasSubLinks = true, so this is only relevant to un-flattened subqueries.
774 : * Second, we have to preserve any varnullingrels info attached to the
775 : * alias Vars we're replacing. If the replacement expression is a Var or
776 : * PlaceHolderVar or constructed from those, we can just add the
777 : * varnullingrels bits to the existing nullingrels field(s); otherwise
778 : * we have to add a PlaceHolderVar wrapper.
779 : *
780 : * NOTE: this is also used by the parser, to expand join alias Vars before
781 : * checking GROUP BY validity. For that use-case, root will be NULL, which
782 : * is why we have to pass the Query separately. We need the root itself only
783 : * for making PlaceHolderVars. We can avoid making PlaceHolderVars in the
784 : * parser's usage because it won't be dealing with arbitrary expressions:
785 : * so long as adjust_standard_join_alias_expression can handle everything
786 : * the parser would make as a join alias expression, we're OK.
787 : */
788 : Node *
789 237004 : flatten_join_alias_vars(PlannerInfo *root, Query *query, Node *node)
790 : {
791 : flatten_join_alias_vars_context context;
792 :
793 : /*
794 : * We do not expect this to be applied to the whole Query, only to
795 : * expressions or LATERAL subqueries. Hence, if the top node is a Query,
796 : * it's okay to immediately increment sublevels_up.
797 : */
798 : Assert(node != (Node *) query);
799 :
800 237004 : context.root = root;
801 237004 : context.query = query;
802 237004 : context.sublevels_up = 0;
803 : /* flag whether join aliases could possibly contain SubLinks */
804 237004 : context.possible_sublink = query->hasSubLinks;
805 : /* if hasSubLinks is already true, no need to work hard */
806 237004 : context.inserted_sublink = query->hasSubLinks;
807 :
808 237004 : return flatten_join_alias_vars_mutator(node, &context);
809 : }
810 :
811 : static Node *
812 3378396 : flatten_join_alias_vars_mutator(Node *node,
813 : flatten_join_alias_vars_context *context)
814 : {
815 3378396 : if (node == NULL)
816 304596 : return NULL;
817 3073800 : if (IsA(node, Var))
818 : {
819 938466 : Var *var = (Var *) node;
820 : RangeTblEntry *rte;
821 : Node *newvar;
822 :
823 : /* No change unless Var belongs to a JOIN of the target level */
824 938466 : if (var->varlevelsup != context->sublevels_up)
825 56688 : return node; /* no need to copy, really */
826 881778 : rte = rt_fetch(var->varno, context->query->rtable);
827 881778 : if (rte->rtekind != RTE_JOIN)
828 881292 : return node;
829 486 : if (var->varattno == InvalidAttrNumber)
830 : {
831 : /* Must expand whole-row reference */
832 : RowExpr *rowexpr;
833 6 : List *fields = NIL;
834 6 : List *colnames = NIL;
835 : ListCell *lv;
836 : ListCell *ln;
837 :
838 : Assert(list_length(rte->joinaliasvars) == list_length(rte->eref->colnames));
839 48 : forboth(lv, rte->joinaliasvars, ln, rte->eref->colnames)
840 : {
841 42 : newvar = (Node *) lfirst(lv);
842 : /* Ignore dropped columns */
843 42 : if (newvar == NULL)
844 0 : continue;
845 42 : newvar = copyObject(newvar);
846 :
847 : /*
848 : * If we are expanding an alias carried down from an upper
849 : * query, must adjust its varlevelsup fields.
850 : */
851 42 : if (context->sublevels_up != 0)
852 0 : IncrementVarSublevelsUp(newvar, context->sublevels_up, 0);
853 : /* Preserve original Var's location, if possible */
854 42 : if (IsA(newvar, Var))
855 42 : ((Var *) newvar)->location = var->location;
856 : /* Recurse in case join input is itself a join */
857 : /* (also takes care of setting inserted_sublink if needed) */
858 42 : newvar = flatten_join_alias_vars_mutator(newvar, context);
859 42 : fields = lappend(fields, newvar);
860 : /* We need the names of non-dropped columns, too */
861 42 : colnames = lappend(colnames, copyObject((Node *) lfirst(ln)));
862 : }
863 6 : rowexpr = makeNode(RowExpr);
864 6 : rowexpr->args = fields;
865 6 : rowexpr->row_typeid = var->vartype;
866 6 : rowexpr->row_format = COERCE_IMPLICIT_CAST;
867 : /* vartype will always be RECORDOID, so we always need colnames */
868 6 : rowexpr->colnames = colnames;
869 6 : rowexpr->location = var->location;
870 :
871 : /* Lastly, add any varnullingrels to the replacement expression */
872 6 : return add_nullingrels_if_needed(context->root, (Node *) rowexpr,
873 : var);
874 : }
875 :
876 : /* Expand join alias reference */
877 : Assert(var->varattno > 0);
878 480 : newvar = (Node *) list_nth(rte->joinaliasvars, var->varattno - 1);
879 : Assert(newvar != NULL);
880 480 : newvar = copyObject(newvar);
881 :
882 : /*
883 : * If we are expanding an alias carried down from an upper query, must
884 : * adjust its varlevelsup fields.
885 : */
886 480 : if (context->sublevels_up != 0)
887 0 : IncrementVarSublevelsUp(newvar, context->sublevels_up, 0);
888 :
889 : /* Preserve original Var's location, if possible */
890 480 : if (IsA(newvar, Var))
891 0 : ((Var *) newvar)->location = var->location;
892 :
893 : /* Recurse in case join input is itself a join */
894 480 : newvar = flatten_join_alias_vars_mutator(newvar, context);
895 :
896 : /* Detect if we are adding a sublink to query */
897 480 : if (context->possible_sublink && !context->inserted_sublink)
898 0 : context->inserted_sublink = checkExprHasSubLink(newvar);
899 :
900 : /* Lastly, add any varnullingrels to the replacement expression */
901 480 : return add_nullingrels_if_needed(context->root, newvar, var);
902 : }
903 2135334 : if (IsA(node, PlaceHolderVar))
904 : {
905 : /* Copy the PlaceHolderVar node with correct mutation of subnodes */
906 : PlaceHolderVar *phv;
907 :
908 2128 : phv = (PlaceHolderVar *) expression_tree_mutator(node,
909 : flatten_join_alias_vars_mutator,
910 : context);
911 : /* now fix PlaceHolderVar's relid sets */
912 2128 : if (phv->phlevelsup == context->sublevels_up)
913 : {
914 2032 : phv->phrels = alias_relid_set(context->query,
915 : phv->phrels);
916 : /* we *don't* change phnullingrels */
917 : }
918 2128 : return (Node *) phv;
919 : }
920 :
921 2133206 : if (IsA(node, Query))
922 : {
923 : /* Recurse into RTE subquery or not-yet-planned sublink subquery */
924 : Query *newnode;
925 : bool save_inserted_sublink;
926 :
927 16966 : context->sublevels_up++;
928 16966 : save_inserted_sublink = context->inserted_sublink;
929 16966 : context->inserted_sublink = ((Query *) node)->hasSubLinks;
930 16966 : newnode = query_tree_mutator((Query *) node,
931 : flatten_join_alias_vars_mutator,
932 : context,
933 : QTW_IGNORE_JOINALIASES);
934 16966 : newnode->hasSubLinks |= context->inserted_sublink;
935 16966 : context->inserted_sublink = save_inserted_sublink;
936 16966 : context->sublevels_up--;
937 16966 : return (Node *) newnode;
938 : }
939 : /* Already-planned tree not supported */
940 : Assert(!IsA(node, SubPlan));
941 : Assert(!IsA(node, AlternativeSubPlan));
942 : /* Shouldn't need to handle these planner auxiliary nodes here */
943 : Assert(!IsA(node, SpecialJoinInfo));
944 : Assert(!IsA(node, PlaceHolderInfo));
945 : Assert(!IsA(node, MinMaxAggInfo));
946 :
947 2116240 : return expression_tree_mutator(node, flatten_join_alias_vars_mutator, context);
948 : }
949 :
950 : /*
951 : * flatten_group_exprs
952 : * Replace Vars that reference GROUP outputs with the underlying grouping
953 : * expressions.
954 : *
955 : * We have to preserve any varnullingrels info attached to the group Vars we're
956 : * replacing. If the replacement expression is a Var or PlaceHolderVar or
957 : * constructed from those, we can just add the varnullingrels bits to the
958 : * existing nullingrels field(s); otherwise we have to add a PlaceHolderVar
959 : * wrapper.
960 : *
961 : * NOTE: this is also used by ruleutils.c, to deparse one query parsetree back
962 : * to source text. For that use-case, root will be NULL, which is why we have
963 : * to pass the Query separately. We need the root itself only for preserving
964 : * varnullingrels. We can avoid preserving varnullingrels in the ruleutils.c's
965 : * usage because it does not make any difference to the deparsed source text.
966 : */
967 : Node *
968 9456 : flatten_group_exprs(PlannerInfo *root, Query *query, Node *node)
969 : {
970 : flatten_join_alias_vars_context context;
971 :
972 : /*
973 : * We do not expect this to be applied to the whole Query, only to
974 : * expressions or LATERAL subqueries. Hence, if the top node is a Query,
975 : * it's okay to immediately increment sublevels_up.
976 : */
977 : Assert(node != (Node *) query);
978 :
979 9456 : context.root = root;
980 9456 : context.query = query;
981 9456 : context.sublevels_up = 0;
982 : /* flag whether grouping expressions could possibly contain SubLinks */
983 9456 : context.possible_sublink = query->hasSubLinks;
984 : /* if hasSubLinks is already true, no need to work hard */
985 9456 : context.inserted_sublink = query->hasSubLinks;
986 :
987 9456 : return flatten_group_exprs_mutator(node, &context);
988 : }
989 :
990 : static Node *
991 62468 : flatten_group_exprs_mutator(Node *node,
992 : flatten_join_alias_vars_context *context)
993 : {
994 62468 : if (node == NULL)
995 10632 : return NULL;
996 51836 : if (IsA(node, Var))
997 : {
998 9858 : Var *var = (Var *) node;
999 : RangeTblEntry *rte;
1000 : Node *newvar;
1001 :
1002 : /* No change unless Var belongs to the GROUP of the target level */
1003 9858 : if (var->varlevelsup != context->sublevels_up)
1004 0 : return node; /* no need to copy, really */
1005 9858 : rte = rt_fetch(var->varno, context->query->rtable);
1006 9858 : if (rte->rtekind != RTE_GROUP)
1007 322 : return node;
1008 :
1009 : /* Expand group exprs reference */
1010 : Assert(var->varattno > 0);
1011 9536 : newvar = (Node *) list_nth(rte->groupexprs, var->varattno - 1);
1012 : Assert(newvar != NULL);
1013 9536 : newvar = copyObject(newvar);
1014 :
1015 : /*
1016 : * If we are expanding an expr carried down from an upper query, must
1017 : * adjust its varlevelsup fields.
1018 : */
1019 9536 : if (context->sublevels_up != 0)
1020 0 : IncrementVarSublevelsUp(newvar, context->sublevels_up, 0);
1021 :
1022 : /* Preserve original Var's location, if possible */
1023 9536 : if (IsA(newvar, Var))
1024 7260 : ((Var *) newvar)->location = var->location;
1025 :
1026 : /* Detect if we are adding a sublink to query */
1027 9536 : if (context->possible_sublink && !context->inserted_sublink)
1028 0 : context->inserted_sublink = checkExprHasSubLink(newvar);
1029 :
1030 : /* Lastly, add any varnullingrels to the replacement expression */
1031 9536 : return mark_nullable_by_grouping(context->root, newvar, var);
1032 : }
1033 :
1034 41978 : if (IsA(node, Aggref))
1035 : {
1036 6152 : Aggref *agg = (Aggref *) node;
1037 :
1038 6152 : if ((int) agg->agglevelsup == context->sublevels_up)
1039 : {
1040 : /*
1041 : * If we find an aggregate call of the original level, do not
1042 : * recurse into its normal arguments, ORDER BY arguments, or
1043 : * filter; there are no grouped vars there. But we should check
1044 : * direct arguments as though they weren't in an aggregate.
1045 : */
1046 6152 : agg = copyObject(agg);
1047 6152 : agg->aggdirectargs = (List *)
1048 6152 : flatten_group_exprs_mutator((Node *) agg->aggdirectargs, context);
1049 :
1050 6152 : return (Node *) agg;
1051 : }
1052 :
1053 : /*
1054 : * We can skip recursing into aggregates of higher levels altogether,
1055 : * since they could not possibly contain Vars of concern to us (see
1056 : * transformAggregateCall). We do need to look at aggregates of lower
1057 : * levels, however.
1058 : */
1059 0 : if ((int) agg->agglevelsup > context->sublevels_up)
1060 0 : return node;
1061 : }
1062 :
1063 35826 : if (IsA(node, GroupingFunc))
1064 : {
1065 356 : GroupingFunc *grp = (GroupingFunc *) node;
1066 :
1067 : /*
1068 : * If we find a GroupingFunc node of the original or higher level, do
1069 : * not recurse into its arguments; there are no grouped vars there.
1070 : */
1071 356 : if ((int) grp->agglevelsup >= context->sublevels_up)
1072 356 : return node;
1073 : }
1074 :
1075 35470 : if (IsA(node, Query))
1076 : {
1077 : /* Recurse into RTE subquery or not-yet-planned sublink subquery */
1078 : Query *newnode;
1079 : bool save_inserted_sublink;
1080 :
1081 0 : context->sublevels_up++;
1082 0 : save_inserted_sublink = context->inserted_sublink;
1083 0 : context->inserted_sublink = ((Query *) node)->hasSubLinks;
1084 0 : newnode = query_tree_mutator((Query *) node,
1085 : flatten_group_exprs_mutator,
1086 : context,
1087 : QTW_IGNORE_GROUPEXPRS);
1088 0 : newnode->hasSubLinks |= context->inserted_sublink;
1089 0 : context->inserted_sublink = save_inserted_sublink;
1090 0 : context->sublevels_up--;
1091 0 : return (Node *) newnode;
1092 : }
1093 :
1094 35470 : return expression_tree_mutator(node, flatten_group_exprs_mutator,
1095 : context);
1096 : }
1097 :
1098 : /*
1099 : * Add oldvar's varnullingrels, if any, to a flattened grouping expression.
1100 : * The newnode has been copied, so we can modify it freely.
1101 : */
1102 : static Node *
1103 9536 : mark_nullable_by_grouping(PlannerInfo *root, Node *newnode, Var *oldvar)
1104 : {
1105 : Relids relids;
1106 :
1107 9536 : if (root == NULL)
1108 738 : return newnode;
1109 8798 : if (oldvar->varnullingrels == NULL)
1110 6992 : return newnode; /* nothing to do */
1111 :
1112 : Assert(bms_equal(oldvar->varnullingrels,
1113 : bms_make_singleton(root->group_rtindex)));
1114 :
1115 1806 : relids = pull_varnos_of_level(root, newnode, oldvar->varlevelsup);
1116 :
1117 1806 : if (!bms_is_empty(relids))
1118 : {
1119 : /*
1120 : * If the newnode is not variable-free, we set the nullingrels of Vars
1121 : * or PHVs that are contained in the expression. This is not really
1122 : * 'correct' in theory, because it is the whole expression that can be
1123 : * nullable by grouping sets, not its individual vars. But it works
1124 : * in practice, because what we need is that the expression can be
1125 : * somehow distinguished from the same expression in ECs, and marking
1126 : * its vars is sufficient for this purpose.
1127 : */
1128 1764 : newnode = add_nulling_relids(newnode,
1129 : relids,
1130 1764 : oldvar->varnullingrels);
1131 : }
1132 : else /* variable-free? */
1133 : {
1134 : /*
1135 : * If the newnode is variable-free and does not contain volatile
1136 : * functions or set-returning functions, it can be treated as a member
1137 : * of EC that is redundant. So wrap it in a new PlaceHolderVar to
1138 : * carry the nullingrels. Otherwise we do not bother to make any
1139 : * changes.
1140 : *
1141 : * Aggregate functions and window functions are not allowed in
1142 : * grouping expressions.
1143 : */
1144 : Assert(!contain_agg_clause(newnode));
1145 : Assert(!contain_window_function(newnode));
1146 :
1147 42 : if (!contain_volatile_functions(newnode) &&
1148 42 : !expression_returns_set(newnode))
1149 : {
1150 : PlaceHolderVar *newphv;
1151 : Relids phrels;
1152 :
1153 24 : phrels = get_relids_in_jointree((Node *) root->parse->jointree,
1154 : true, false);
1155 : Assert(!bms_is_empty(phrels));
1156 :
1157 24 : newphv = make_placeholder_expr(root, (Expr *) newnode, phrels);
1158 : /* newphv has zero phlevelsup and NULL phnullingrels; fix it */
1159 24 : newphv->phlevelsup = oldvar->varlevelsup;
1160 24 : newphv->phnullingrels = bms_copy(oldvar->varnullingrels);
1161 24 : newnode = (Node *) newphv;
1162 : }
1163 : }
1164 :
1165 1806 : return newnode;
1166 : }
1167 :
1168 : /*
1169 : * Add oldvar's varnullingrels, if any, to a flattened join alias expression.
1170 : * The newnode has been copied, so we can modify it freely.
1171 : */
1172 : static Node *
1173 486 : add_nullingrels_if_needed(PlannerInfo *root, Node *newnode, Var *oldvar)
1174 : {
1175 486 : if (oldvar->varnullingrels == NULL)
1176 342 : return newnode; /* nothing to do */
1177 : /* If possible, do it by adding to existing nullingrel fields */
1178 144 : if (is_standard_join_alias_expression(newnode, oldvar))
1179 132 : adjust_standard_join_alias_expression(newnode, oldvar);
1180 12 : else if (root)
1181 : {
1182 : /*
1183 : * We can insert a PlaceHolderVar to carry the nullingrels. However,
1184 : * deciding where to evaluate the PHV is slightly tricky. We first
1185 : * try to evaluate it at the natural semantic level of the new
1186 : * expression; but if that expression is variable-free, fall back to
1187 : * evaluating it at the join that the oldvar is an alias Var for.
1188 : */
1189 : PlaceHolderVar *newphv;
1190 12 : Index levelsup = oldvar->varlevelsup;
1191 12 : Relids phrels = pull_varnos_of_level(root, newnode, levelsup);
1192 :
1193 12 : if (bms_is_empty(phrels)) /* variable-free? */
1194 : {
1195 12 : if (levelsup != 0) /* this won't work otherwise */
1196 0 : elog(ERROR, "unsupported join alias expression");
1197 12 : phrels = get_relids_for_join(root->parse, oldvar->varno);
1198 : /* If it's an outer join, eval below not above the join */
1199 12 : phrels = bms_del_member(phrels, oldvar->varno);
1200 : Assert(!bms_is_empty(phrels));
1201 : }
1202 12 : newphv = make_placeholder_expr(root, (Expr *) newnode, phrels);
1203 : /* newphv has zero phlevelsup and NULL phnullingrels; fix it */
1204 12 : newphv->phlevelsup = levelsup;
1205 12 : newphv->phnullingrels = bms_copy(oldvar->varnullingrels);
1206 12 : newnode = (Node *) newphv;
1207 : }
1208 : else
1209 : {
1210 : /* ooops, we're missing support for something the parser can make */
1211 0 : elog(ERROR, "unsupported join alias expression");
1212 : }
1213 144 : return newnode;
1214 : }
1215 :
1216 : /*
1217 : * Check to see if we can insert nullingrels into this join alias expression
1218 : * without use of a separate PlaceHolderVar.
1219 : *
1220 : * This will handle Vars, PlaceHolderVars, and implicit-coercion and COALESCE
1221 : * expressions built from those. This coverage needs to handle anything
1222 : * that the parser would put into joinaliasvars.
1223 : */
1224 : static bool
1225 444 : is_standard_join_alias_expression(Node *newnode, Var *oldvar)
1226 : {
1227 444 : if (newnode == NULL)
1228 0 : return false;
1229 444 : if (IsA(newnode, Var) &&
1230 264 : ((Var *) newnode)->varlevelsup == oldvar->varlevelsup)
1231 264 : return true;
1232 180 : else if (IsA(newnode, PlaceHolderVar) &&
1233 0 : ((PlaceHolderVar *) newnode)->phlevelsup == oldvar->varlevelsup)
1234 0 : return true;
1235 180 : else if (IsA(newnode, FuncExpr))
1236 : {
1237 24 : FuncExpr *fexpr = (FuncExpr *) newnode;
1238 :
1239 : /*
1240 : * We need to assume that the function wouldn't produce non-NULL from
1241 : * NULL, which is reasonable for implicit coercions but otherwise not
1242 : * so much. (Looking at its strictness is likely overkill, and anyway
1243 : * it would cause us to fail if someone forgot to mark an implicit
1244 : * coercion as strict.)
1245 : */
1246 24 : if (fexpr->funcformat != COERCE_IMPLICIT_CAST ||
1247 24 : fexpr->args == NIL)
1248 0 : return false;
1249 :
1250 : /*
1251 : * Examine only the first argument --- coercions might have additional
1252 : * arguments that are constants.
1253 : */
1254 24 : return is_standard_join_alias_expression(linitial(fexpr->args), oldvar);
1255 : }
1256 156 : else if (IsA(newnode, RelabelType))
1257 : {
1258 12 : RelabelType *relabel = (RelabelType *) newnode;
1259 :
1260 : /* This definitely won't produce non-NULL from NULL */
1261 12 : return is_standard_join_alias_expression((Node *) relabel->arg, oldvar);
1262 : }
1263 144 : else if (IsA(newnode, CoerceViaIO))
1264 : {
1265 0 : CoerceViaIO *iocoerce = (CoerceViaIO *) newnode;
1266 :
1267 : /* This definitely won't produce non-NULL from NULL */
1268 0 : return is_standard_join_alias_expression((Node *) iocoerce->arg, oldvar);
1269 : }
1270 144 : else if (IsA(newnode, ArrayCoerceExpr))
1271 : {
1272 0 : ArrayCoerceExpr *acoerce = (ArrayCoerceExpr *) newnode;
1273 :
1274 : /* This definitely won't produce non-NULL from NULL (at array level) */
1275 0 : return is_standard_join_alias_expression((Node *) acoerce->arg, oldvar);
1276 : }
1277 144 : else if (IsA(newnode, CoalesceExpr))
1278 : {
1279 132 : CoalesceExpr *cexpr = (CoalesceExpr *) newnode;
1280 : ListCell *lc;
1281 :
1282 : Assert(cexpr->args != NIL);
1283 396 : foreach(lc, cexpr->args)
1284 : {
1285 264 : if (!is_standard_join_alias_expression(lfirst(lc), oldvar))
1286 0 : return false;
1287 : }
1288 132 : return true;
1289 : }
1290 : else
1291 12 : return false;
1292 : }
1293 :
1294 : /*
1295 : * Insert nullingrels into an expression accepted by
1296 : * is_standard_join_alias_expression.
1297 : */
1298 : static void
1299 420 : adjust_standard_join_alias_expression(Node *newnode, Var *oldvar)
1300 : {
1301 420 : if (IsA(newnode, Var) &&
1302 264 : ((Var *) newnode)->varlevelsup == oldvar->varlevelsup)
1303 264 : {
1304 264 : Var *newvar = (Var *) newnode;
1305 :
1306 264 : newvar->varnullingrels = bms_add_members(newvar->varnullingrels,
1307 264 : oldvar->varnullingrels);
1308 : }
1309 156 : else if (IsA(newnode, PlaceHolderVar) &&
1310 0 : ((PlaceHolderVar *) newnode)->phlevelsup == oldvar->varlevelsup)
1311 0 : {
1312 0 : PlaceHolderVar *newphv = (PlaceHolderVar *) newnode;
1313 :
1314 0 : newphv->phnullingrels = bms_add_members(newphv->phnullingrels,
1315 0 : oldvar->varnullingrels);
1316 : }
1317 156 : else if (IsA(newnode, FuncExpr))
1318 : {
1319 12 : FuncExpr *fexpr = (FuncExpr *) newnode;
1320 :
1321 12 : adjust_standard_join_alias_expression(linitial(fexpr->args), oldvar);
1322 : }
1323 144 : else if (IsA(newnode, RelabelType))
1324 : {
1325 12 : RelabelType *relabel = (RelabelType *) newnode;
1326 :
1327 12 : adjust_standard_join_alias_expression((Node *) relabel->arg, oldvar);
1328 : }
1329 132 : else if (IsA(newnode, CoerceViaIO))
1330 : {
1331 0 : CoerceViaIO *iocoerce = (CoerceViaIO *) newnode;
1332 :
1333 0 : adjust_standard_join_alias_expression((Node *) iocoerce->arg, oldvar);
1334 : }
1335 132 : else if (IsA(newnode, ArrayCoerceExpr))
1336 : {
1337 0 : ArrayCoerceExpr *acoerce = (ArrayCoerceExpr *) newnode;
1338 :
1339 0 : adjust_standard_join_alias_expression((Node *) acoerce->arg, oldvar);
1340 : }
1341 132 : else if (IsA(newnode, CoalesceExpr))
1342 : {
1343 132 : CoalesceExpr *cexpr = (CoalesceExpr *) newnode;
1344 : ListCell *lc;
1345 :
1346 : Assert(cexpr->args != NIL);
1347 396 : foreach(lc, cexpr->args)
1348 : {
1349 264 : adjust_standard_join_alias_expression(lfirst(lc), oldvar);
1350 : }
1351 : }
1352 : else
1353 : Assert(false);
1354 420 : }
1355 :
1356 : /*
1357 : * alias_relid_set: in a set of RT indexes, replace joins by their
1358 : * underlying base+OJ relids
1359 : */
1360 : static Relids
1361 2032 : alias_relid_set(Query *query, Relids relids)
1362 : {
1363 2032 : Relids result = NULL;
1364 : int rtindex;
1365 :
1366 2032 : rtindex = -1;
1367 5052 : while ((rtindex = bms_next_member(relids, rtindex)) >= 0)
1368 : {
1369 3020 : RangeTblEntry *rte = rt_fetch(rtindex, query->rtable);
1370 :
1371 3020 : if (rte->rtekind == RTE_JOIN)
1372 346 : result = bms_join(result, get_relids_for_join(query, rtindex));
1373 : else
1374 2674 : result = bms_add_member(result, rtindex);
1375 : }
1376 2032 : return result;
1377 : }
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