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) 1996-2024, 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 locate_var_of_level_walker(Node *node,
80 : locate_var_of_level_context *context);
81 : static bool pull_var_clause_walker(Node *node,
82 : pull_var_clause_context *context);
83 : static Node *flatten_join_alias_vars_mutator(Node *node,
84 : flatten_join_alias_vars_context *context);
85 : static Node *flatten_group_exprs_mutator(Node *node,
86 : flatten_join_alias_vars_context *context);
87 : static Node *mark_nullable_by_grouping(PlannerInfo *root, Node *newnode,
88 : Var *oldvar);
89 : static Node *add_nullingrels_if_needed(PlannerInfo *root, Node *newnode,
90 : Var *oldvar);
91 : static bool is_standard_join_alias_expression(Node *newnode, Var *oldvar);
92 : static void adjust_standard_join_alias_expression(Node *newnode, Var *oldvar);
93 : static Relids alias_relid_set(Query *query, Relids relids);
94 :
95 :
96 : /*
97 : * pull_varnos
98 : * Create a set of all the distinct varnos present in a parsetree.
99 : * Only varnos that reference level-zero rtable entries are considered.
100 : *
101 : * The result includes outer-join relids mentioned in Var.varnullingrels and
102 : * PlaceHolderVar.phnullingrels fields in the parsetree.
103 : *
104 : * "root" can be passed as NULL if it is not necessary to process
105 : * PlaceHolderVars.
106 : *
107 : * NOTE: this is used on not-yet-planned expressions. It may therefore find
108 : * bare SubLinks, and if so it needs to recurse into them to look for uplevel
109 : * references to the desired rtable level! But when we find a completed
110 : * SubPlan, we only need to look at the parameters passed to the subplan.
111 : */
112 : Relids
113 2843186 : pull_varnos(PlannerInfo *root, Node *node)
114 : {
115 : pull_varnos_context context;
116 :
117 2843186 : context.varnos = NULL;
118 2843186 : context.root = root;
119 2843186 : context.sublevels_up = 0;
120 :
121 : /*
122 : * Must be prepared to start with a Query or a bare expression tree; if
123 : * it's a Query, we don't want to increment sublevels_up.
124 : */
125 2843186 : query_or_expression_tree_walker(node,
126 : pull_varnos_walker,
127 : (void *) &context,
128 : 0);
129 :
130 2843186 : return context.varnos;
131 : }
132 :
133 : /*
134 : * pull_varnos_of_level
135 : * Create a set of all the distinct varnos present in a parsetree.
136 : * Only Vars of the specified level are considered.
137 : */
138 : Relids
139 4912 : pull_varnos_of_level(PlannerInfo *root, Node *node, int levelsup)
140 : {
141 : pull_varnos_context context;
142 :
143 4912 : context.varnos = NULL;
144 4912 : context.root = root;
145 4912 : context.sublevels_up = levelsup;
146 :
147 : /*
148 : * Must be prepared to start with a Query or a bare expression tree; if
149 : * it's a Query, we don't want to increment sublevels_up.
150 : */
151 4912 : query_or_expression_tree_walker(node,
152 : pull_varnos_walker,
153 : (void *) &context,
154 : 0);
155 :
156 4912 : return context.varnos;
157 : }
158 :
159 : static bool
160 4807246 : pull_varnos_walker(Node *node, pull_varnos_context *context)
161 : {
162 4807246 : if (node == NULL)
163 110646 : return false;
164 4696600 : if (IsA(node, Var))
165 : {
166 2301964 : Var *var = (Var *) node;
167 :
168 2301964 : if (var->varlevelsup == context->sublevels_up)
169 : {
170 2296312 : context->varnos = bms_add_member(context->varnos, var->varno);
171 2296312 : context->varnos = bms_add_members(context->varnos,
172 2296312 : var->varnullingrels);
173 : }
174 2301964 : return false;
175 : }
176 2394636 : if (IsA(node, CurrentOfExpr))
177 : {
178 800 : CurrentOfExpr *cexpr = (CurrentOfExpr *) node;
179 :
180 800 : if (context->sublevels_up == 0)
181 800 : context->varnos = bms_add_member(context->varnos, cexpr->cvarno);
182 800 : return false;
183 : }
184 2393836 : if (IsA(node, PlaceHolderVar))
185 : {
186 5232 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
187 :
188 : /*
189 : * If a PlaceHolderVar is not of the target query level, ignore it,
190 : * instead recursing into its expression to see if it contains any
191 : * vars that are of the target level. We'll also do that when the
192 : * caller doesn't pass a "root" pointer. (We probably shouldn't see
193 : * PlaceHolderVars at all in such cases, but if we do, this is a
194 : * reasonable behavior.)
195 : */
196 5232 : if (phv->phlevelsup == context->sublevels_up &&
197 5232 : context->root != NULL)
198 : {
199 : /*
200 : * Ideally, the PHV's contribution to context->varnos is its
201 : * ph_eval_at set. However, this code can be invoked before
202 : * that's been computed. If we cannot find a PlaceHolderInfo,
203 : * fall back to the conservative assumption that the PHV will be
204 : * evaluated at its syntactic level (phv->phrels).
205 : *
206 : * Another problem is that a PlaceHolderVar can appear in quals or
207 : * tlists that have been translated for use in a child appendrel.
208 : * Typically such a PHV is a parameter expression sourced by some
209 : * other relation, so that the translation from parent appendrel
210 : * to child doesn't change its phrels, and we should still take
211 : * ph_eval_at at face value. But in corner cases, the PHV's
212 : * original phrels can include the parent appendrel itself, in
213 : * which case the translated PHV will have the child appendrel in
214 : * phrels, and we must translate ph_eval_at to match.
215 : */
216 5232 : PlaceHolderInfo *phinfo = NULL;
217 :
218 5232 : if (phv->phlevelsup == 0)
219 : {
220 5184 : if (phv->phid < context->root->placeholder_array_size)
221 4274 : phinfo = context->root->placeholder_array[phv->phid];
222 : }
223 5232 : if (phinfo == NULL)
224 : {
225 : /* No PlaceHolderInfo yet, use phrels */
226 970 : context->varnos = bms_add_members(context->varnos,
227 970 : phv->phrels);
228 : }
229 4262 : else if (bms_equal(phv->phrels, phinfo->ph_var->phrels))
230 : {
231 : /* Normal case: use ph_eval_at */
232 3368 : context->varnos = bms_add_members(context->varnos,
233 3368 : phinfo->ph_eval_at);
234 : }
235 : else
236 : {
237 : /* Translated PlaceHolderVar: translate ph_eval_at to match */
238 : Relids newevalat,
239 : delta;
240 :
241 : /* remove what was removed from phv->phrels ... */
242 894 : delta = bms_difference(phinfo->ph_var->phrels, phv->phrels);
243 894 : newevalat = bms_difference(phinfo->ph_eval_at, delta);
244 : /* ... then if that was in fact part of ph_eval_at ... */
245 894 : if (!bms_equal(newevalat, phinfo->ph_eval_at))
246 : {
247 : /* ... add what was added */
248 600 : delta = bms_difference(phv->phrels, phinfo->ph_var->phrels);
249 600 : newevalat = bms_join(newevalat, delta);
250 : }
251 894 : context->varnos = bms_join(context->varnos,
252 : newevalat);
253 : }
254 :
255 : /*
256 : * In all three cases, include phnullingrels in the result. We
257 : * don't worry about possibly needing to translate it, because
258 : * appendrels only translate varnos of baserels, not outer joins.
259 : */
260 10464 : context->varnos = bms_add_members(context->varnos,
261 5232 : phv->phnullingrels);
262 5232 : return false; /* don't recurse into expression */
263 : }
264 : }
265 2388604 : else if (IsA(node, Query))
266 : {
267 : /* Recurse into RTE subquery or not-yet-planned sublink subquery */
268 : bool result;
269 :
270 1630 : context->sublevels_up++;
271 1630 : result = query_tree_walker((Query *) node, pull_varnos_walker,
272 : (void *) context, 0);
273 1630 : context->sublevels_up--;
274 1630 : return result;
275 : }
276 2386974 : return expression_tree_walker(node, pull_varnos_walker,
277 : (void *) 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 1608914 : pull_varattnos(Node *node, Index varno, Bitmapset **varattnos)
297 : {
298 : pull_varattnos_context context;
299 :
300 1608914 : context.varattnos = *varattnos;
301 1608914 : context.varno = varno;
302 :
303 1608914 : (void) pull_varattnos_walker(node, &context);
304 :
305 1608914 : *varattnos = context.varattnos;
306 1608914 : }
307 :
308 : static bool
309 5323370 : pull_varattnos_walker(Node *node, pull_varattnos_context *context)
310 : {
311 5323370 : if (node == NULL)
312 73992 : return false;
313 5249378 : if (IsA(node, Var))
314 : {
315 3012660 : Var *var = (Var *) node;
316 :
317 3012660 : if (var->varno == context->varno && var->varlevelsup == 0)
318 3012234 : context->varattnos =
319 3012234 : bms_add_member(context->varattnos,
320 3012234 : var->varattno - FirstLowInvalidHeapAttributeNumber);
321 3012660 : return false;
322 : }
323 :
324 : /* Should not find an unplanned subquery */
325 : Assert(!IsA(node, Query));
326 :
327 2236718 : return expression_tree_walker(node, pull_varattnos_walker,
328 : (void *) context);
329 : }
330 :
331 :
332 : /*
333 : * pull_vars_of_level
334 : * Create a list of all Vars (and PlaceHolderVars) referencing the
335 : * specified query level in the given parsetree.
336 : *
337 : * Caution: the Vars are not copied, only linked into the list.
338 : */
339 : List *
340 9612 : pull_vars_of_level(Node *node, int levelsup)
341 : {
342 : pull_vars_context context;
343 :
344 9612 : context.vars = NIL;
345 9612 : context.sublevels_up = levelsup;
346 :
347 : /*
348 : * Must be prepared to start with a Query or a bare expression tree; if
349 : * it's a Query, we don't want to increment sublevels_up.
350 : */
351 9612 : query_or_expression_tree_walker(node,
352 : pull_vars_walker,
353 : (void *) &context,
354 : 0);
355 :
356 9612 : return context.vars;
357 : }
358 :
359 : static bool
360 110334 : pull_vars_walker(Node *node, pull_vars_context *context)
361 : {
362 110334 : if (node == NULL)
363 12536 : return false;
364 97798 : if (IsA(node, Var))
365 : {
366 12950 : Var *var = (Var *) node;
367 :
368 12950 : if (var->varlevelsup == context->sublevels_up)
369 10416 : context->vars = lappend(context->vars, var);
370 12950 : return false;
371 : }
372 84848 : if (IsA(node, PlaceHolderVar))
373 : {
374 84 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
375 :
376 84 : if (phv->phlevelsup == context->sublevels_up)
377 84 : context->vars = lappend(context->vars, phv);
378 : /* we don't want to look into the contained expression */
379 84 : return false;
380 : }
381 84764 : if (IsA(node, Query))
382 : {
383 : /* Recurse into RTE subquery or not-yet-planned sublink subquery */
384 : bool result;
385 :
386 300 : context->sublevels_up++;
387 300 : result = query_tree_walker((Query *) node, pull_vars_walker,
388 : (void *) context, 0);
389 300 : context->sublevels_up--;
390 300 : return result;
391 : }
392 84464 : return expression_tree_walker(node, pull_vars_walker,
393 : (void *) context);
394 : }
395 :
396 :
397 : /*
398 : * contain_var_clause
399 : * Recursively scan a clause to discover whether it contains any Var nodes
400 : * (of the current query level).
401 : *
402 : * Returns true if any varnode found.
403 : *
404 : * Does not examine subqueries, therefore must only be used after reduction
405 : * of sublinks to subplans!
406 : */
407 : bool
408 19340 : contain_var_clause(Node *node)
409 : {
410 19340 : return contain_var_clause_walker(node, NULL);
411 : }
412 :
413 : static bool
414 25126 : contain_var_clause_walker(Node *node, void *context)
415 : {
416 25126 : if (node == NULL)
417 106 : return false;
418 25020 : if (IsA(node, Var))
419 : {
420 2210 : if (((Var *) node)->varlevelsup == 0)
421 2210 : return true; /* abort the tree traversal and return true */
422 0 : return false;
423 : }
424 22810 : if (IsA(node, CurrentOfExpr))
425 0 : return true;
426 22810 : if (IsA(node, PlaceHolderVar))
427 : {
428 12 : if (((PlaceHolderVar *) node)->phlevelsup == 0)
429 12 : return true; /* abort the tree traversal and return true */
430 : /* else fall through to check the contained expr */
431 : }
432 22798 : return expression_tree_walker(node, contain_var_clause_walker, context);
433 : }
434 :
435 :
436 : /*
437 : * contain_vars_of_level
438 : * Recursively scan a clause to discover whether it contains any Var nodes
439 : * of the specified query level.
440 : *
441 : * Returns true if any such Var found.
442 : *
443 : * Will recurse into sublinks. Also, may be invoked directly on a Query.
444 : */
445 : bool
446 152028 : contain_vars_of_level(Node *node, int levelsup)
447 : {
448 152028 : int sublevels_up = levelsup;
449 :
450 152028 : return query_or_expression_tree_walker(node,
451 : contain_vars_of_level_walker,
452 : (void *) &sublevels_up,
453 : 0);
454 : }
455 :
456 : static bool
457 462448 : contain_vars_of_level_walker(Node *node, int *sublevels_up)
458 : {
459 462448 : if (node == NULL)
460 82068 : return false;
461 380380 : if (IsA(node, Var))
462 : {
463 63086 : if (((Var *) node)->varlevelsup == *sublevels_up)
464 41356 : return true; /* abort tree traversal and return true */
465 21730 : return false;
466 : }
467 317294 : if (IsA(node, CurrentOfExpr))
468 : {
469 184 : if (*sublevels_up == 0)
470 184 : return true;
471 0 : return false;
472 : }
473 317110 : if (IsA(node, PlaceHolderVar))
474 : {
475 72 : if (((PlaceHolderVar *) node)->phlevelsup == *sublevels_up)
476 72 : return true; /* abort the tree traversal and return true */
477 : /* else fall through to check the contained expr */
478 : }
479 317038 : if (IsA(node, Query))
480 : {
481 : /* Recurse into subselects */
482 : bool result;
483 :
484 598 : (*sublevels_up)++;
485 598 : result = query_tree_walker((Query *) node,
486 : contain_vars_of_level_walker,
487 : (void *) sublevels_up,
488 : 0);
489 598 : (*sublevels_up)--;
490 598 : return result;
491 : }
492 316440 : return expression_tree_walker(node,
493 : contain_vars_of_level_walker,
494 : (void *) sublevels_up);
495 : }
496 :
497 :
498 : /*
499 : * locate_var_of_level
500 : * Find the parse location of any Var of the specified query level.
501 : *
502 : * Returns -1 if no such Var is in the querytree, or if they all have
503 : * unknown parse location. (The former case is probably caller error,
504 : * but we don't bother to distinguish it from the latter case.)
505 : *
506 : * Will recurse into sublinks. Also, may be invoked directly on a Query.
507 : *
508 : * Note: it might seem appropriate to merge this functionality into
509 : * contain_vars_of_level, but that would complicate that function's API.
510 : * Currently, the only uses of this function are for error reporting,
511 : * and so shaving cycles probably isn't very important.
512 : */
513 : int
514 12 : locate_var_of_level(Node *node, int levelsup)
515 : {
516 : locate_var_of_level_context context;
517 :
518 12 : context.var_location = -1; /* in case we find nothing */
519 12 : context.sublevels_up = levelsup;
520 :
521 12 : (void) query_or_expression_tree_walker(node,
522 : locate_var_of_level_walker,
523 : (void *) &context,
524 : 0);
525 :
526 12 : return context.var_location;
527 : }
528 :
529 : static bool
530 30 : locate_var_of_level_walker(Node *node,
531 : locate_var_of_level_context *context)
532 : {
533 30 : if (node == NULL)
534 0 : return false;
535 30 : if (IsA(node, Var))
536 : {
537 12 : Var *var = (Var *) node;
538 :
539 12 : if (var->varlevelsup == context->sublevels_up &&
540 12 : var->location >= 0)
541 : {
542 12 : context->var_location = var->location;
543 12 : return true; /* abort tree traversal and return true */
544 : }
545 0 : return false;
546 : }
547 18 : if (IsA(node, CurrentOfExpr))
548 : {
549 : /* since CurrentOfExpr doesn't carry location, nothing we can do */
550 0 : return false;
551 : }
552 : /* No extra code needed for PlaceHolderVar; just look in contained expr */
553 18 : if (IsA(node, Query))
554 : {
555 : /* Recurse into subselects */
556 : bool result;
557 :
558 0 : context->sublevels_up++;
559 0 : result = query_tree_walker((Query *) node,
560 : locate_var_of_level_walker,
561 : (void *) context,
562 : 0);
563 0 : context->sublevels_up--;
564 0 : return result;
565 : }
566 18 : return expression_tree_walker(node,
567 : locate_var_of_level_walker,
568 : (void *) context);
569 : }
570 :
571 :
572 : /*
573 : * pull_var_clause
574 : * Recursively pulls all Var nodes from an expression clause.
575 : *
576 : * Aggrefs are handled according to these bits in 'flags':
577 : * PVC_INCLUDE_AGGREGATES include Aggrefs in output list
578 : * PVC_RECURSE_AGGREGATES recurse into Aggref arguments
579 : * neither flag throw error if Aggref found
580 : * Vars within an Aggref's expression are included in the result only
581 : * when PVC_RECURSE_AGGREGATES is specified.
582 : *
583 : * WindowFuncs are handled according to these bits in 'flags':
584 : * PVC_INCLUDE_WINDOWFUNCS include WindowFuncs in output list
585 : * PVC_RECURSE_WINDOWFUNCS recurse into WindowFunc arguments
586 : * neither flag throw error if WindowFunc found
587 : * Vars within a WindowFunc's expression are included in the result only
588 : * when PVC_RECURSE_WINDOWFUNCS is specified.
589 : *
590 : * PlaceHolderVars are handled according to these bits in 'flags':
591 : * PVC_INCLUDE_PLACEHOLDERS include PlaceHolderVars in output list
592 : * PVC_RECURSE_PLACEHOLDERS recurse into PlaceHolderVar arguments
593 : * neither flag throw error if PlaceHolderVar found
594 : * Vars within a PHV's expression are included in the result only
595 : * when PVC_RECURSE_PLACEHOLDERS is specified.
596 : *
597 : * GroupingFuncs are treated exactly like Aggrefs, and so do not need
598 : * their own flag bits.
599 : *
600 : * CurrentOfExpr nodes are ignored in all cases.
601 : *
602 : * Upper-level vars (with varlevelsup > 0) should not be seen here,
603 : * likewise for upper-level Aggrefs and PlaceHolderVars.
604 : *
605 : * Returns list of nodes found. Note the nodes themselves are not
606 : * copied, only referenced.
607 : *
608 : * Does not examine subqueries, therefore must only be used after reduction
609 : * of sublinks to subplans!
610 : */
611 : List *
612 662100 : pull_var_clause(Node *node, int flags)
613 : {
614 : pull_var_clause_context context;
615 :
616 : /* Assert that caller has not specified inconsistent flags */
617 : Assert((flags & (PVC_INCLUDE_AGGREGATES | PVC_RECURSE_AGGREGATES))
618 : != (PVC_INCLUDE_AGGREGATES | PVC_RECURSE_AGGREGATES));
619 : Assert((flags & (PVC_INCLUDE_WINDOWFUNCS | PVC_RECURSE_WINDOWFUNCS))
620 : != (PVC_INCLUDE_WINDOWFUNCS | PVC_RECURSE_WINDOWFUNCS));
621 : Assert((flags & (PVC_INCLUDE_PLACEHOLDERS | PVC_RECURSE_PLACEHOLDERS))
622 : != (PVC_INCLUDE_PLACEHOLDERS | PVC_RECURSE_PLACEHOLDERS));
623 :
624 662100 : context.varlist = NIL;
625 662100 : context.flags = flags;
626 :
627 662100 : pull_var_clause_walker(node, &context);
628 662100 : return context.varlist;
629 : }
630 :
631 : static bool
632 4026696 : pull_var_clause_walker(Node *node, pull_var_clause_context *context)
633 : {
634 4026696 : if (node == NULL)
635 171534 : return false;
636 3855162 : if (IsA(node, Var))
637 : {
638 1474982 : if (((Var *) node)->varlevelsup != 0)
639 0 : elog(ERROR, "Upper-level Var found where not expected");
640 1474982 : context->varlist = lappend(context->varlist, node);
641 1474982 : return false;
642 : }
643 2380180 : else if (IsA(node, Aggref))
644 : {
645 92992 : if (((Aggref *) node)->agglevelsup != 0)
646 0 : elog(ERROR, "Upper-level Aggref found where not expected");
647 92992 : if (context->flags & PVC_INCLUDE_AGGREGATES)
648 : {
649 4800 : context->varlist = lappend(context->varlist, node);
650 : /* we do NOT descend into the contained expression */
651 4800 : return false;
652 : }
653 88192 : else if (context->flags & PVC_RECURSE_AGGREGATES)
654 : {
655 : /* fall through to recurse into the aggregate's arguments */
656 : }
657 : else
658 0 : elog(ERROR, "Aggref found where not expected");
659 : }
660 2287188 : else if (IsA(node, GroupingFunc))
661 : {
662 646 : if (((GroupingFunc *) node)->agglevelsup != 0)
663 0 : elog(ERROR, "Upper-level GROUPING found where not expected");
664 646 : if (context->flags & PVC_INCLUDE_AGGREGATES)
665 : {
666 4 : context->varlist = lappend(context->varlist, node);
667 : /* we do NOT descend into the contained expression */
668 4 : return false;
669 : }
670 642 : else if (context->flags & PVC_RECURSE_AGGREGATES)
671 : {
672 : /* fall through to recurse into the GroupingFunc's arguments */
673 : }
674 : else
675 0 : elog(ERROR, "GROUPING found where not expected");
676 : }
677 2286542 : else if (IsA(node, WindowFunc))
678 : {
679 : /* WindowFuncs have no levelsup field to check ... */
680 6472 : if (context->flags & PVC_INCLUDE_WINDOWFUNCS)
681 : {
682 12 : context->varlist = lappend(context->varlist, node);
683 : /* we do NOT descend into the contained expressions */
684 12 : return false;
685 : }
686 6460 : else if (context->flags & PVC_RECURSE_WINDOWFUNCS)
687 : {
688 : /* fall through to recurse into the windowfunc's arguments */
689 : }
690 : else
691 0 : elog(ERROR, "WindowFunc found where not expected");
692 : }
693 2280070 : else if (IsA(node, PlaceHolderVar))
694 : {
695 3056 : if (((PlaceHolderVar *) node)->phlevelsup != 0)
696 0 : elog(ERROR, "Upper-level PlaceHolderVar found where not expected");
697 3056 : if (context->flags & PVC_INCLUDE_PLACEHOLDERS)
698 : {
699 2640 : context->varlist = lappend(context->varlist, node);
700 : /* we do NOT descend into the contained expression */
701 2640 : return false;
702 : }
703 416 : else if (context->flags & PVC_RECURSE_PLACEHOLDERS)
704 : {
705 : /* fall through to recurse into the placeholder's expression */
706 : }
707 : else
708 0 : elog(ERROR, "PlaceHolderVar found where not expected");
709 : }
710 2372724 : return expression_tree_walker(node, pull_var_clause_walker,
711 : (void *) context);
712 : }
713 :
714 :
715 : /*
716 : * flatten_join_alias_vars
717 : * Replace Vars that reference JOIN outputs with references to the original
718 : * relation variables instead. This allows quals involving such vars to be
719 : * pushed down. Whole-row Vars that reference JOIN relations are expanded
720 : * into RowExpr constructs that name the individual output Vars. This
721 : * is necessary since we will not scan the JOIN as a base relation, which
722 : * is the only way that the executor can directly handle whole-row Vars.
723 : *
724 : * This also adjusts relid sets found in some expression node types to
725 : * substitute the contained base+OJ rels for any join relid.
726 : *
727 : * If a JOIN contains sub-selects that have been flattened, its join alias
728 : * entries might now be arbitrary expressions, not just Vars. This affects
729 : * this function in two important ways. First, we might find ourselves
730 : * inserting SubLink expressions into subqueries, and we must make sure that
731 : * their Query.hasSubLinks fields get set to true if so. If there are any
732 : * SubLinks in the join alias lists, the outer Query should already have
733 : * hasSubLinks = true, so this is only relevant to un-flattened subqueries.
734 : * Second, we have to preserve any varnullingrels info attached to the
735 : * alias Vars we're replacing. If the replacement expression is a Var or
736 : * PlaceHolderVar or constructed from those, we can just add the
737 : * varnullingrels bits to the existing nullingrels field(s); otherwise
738 : * we have to add a PlaceHolderVar wrapper.
739 : *
740 : * NOTE: this is also used by the parser, to expand join alias Vars before
741 : * checking GROUP BY validity. For that use-case, root will be NULL, which
742 : * is why we have to pass the Query separately. We need the root itself only
743 : * for making PlaceHolderVars. We can avoid making PlaceHolderVars in the
744 : * parser's usage because it won't be dealing with arbitrary expressions:
745 : * so long as adjust_standard_join_alias_expression can handle everything
746 : * the parser would make as a join alias expression, we're OK.
747 : */
748 : Node *
749 204020 : flatten_join_alias_vars(PlannerInfo *root, Query *query, Node *node)
750 : {
751 : flatten_join_alias_vars_context context;
752 :
753 : /*
754 : * We do not expect this to be applied to the whole Query, only to
755 : * expressions or LATERAL subqueries. Hence, if the top node is a Query,
756 : * it's okay to immediately increment sublevels_up.
757 : */
758 : Assert(node != (Node *) query);
759 :
760 204020 : context.root = root;
761 204020 : context.query = query;
762 204020 : context.sublevels_up = 0;
763 : /* flag whether join aliases could possibly contain SubLinks */
764 204020 : context.possible_sublink = query->hasSubLinks;
765 : /* if hasSubLinks is already true, no need to work hard */
766 204020 : context.inserted_sublink = query->hasSubLinks;
767 :
768 204020 : return flatten_join_alias_vars_mutator(node, &context);
769 : }
770 :
771 : static Node *
772 2780502 : flatten_join_alias_vars_mutator(Node *node,
773 : flatten_join_alias_vars_context *context)
774 : {
775 2780502 : if (node == NULL)
776 243786 : return NULL;
777 2536716 : if (IsA(node, Var))
778 : {
779 770758 : Var *var = (Var *) node;
780 : RangeTblEntry *rte;
781 : Node *newvar;
782 :
783 : /* No change unless Var belongs to a JOIN of the target level */
784 770758 : if (var->varlevelsup != context->sublevels_up)
785 44510 : return node; /* no need to copy, really */
786 726248 : rte = rt_fetch(var->varno, context->query->rtable);
787 726248 : if (rte->rtekind != RTE_JOIN)
788 725762 : return node;
789 486 : if (var->varattno == InvalidAttrNumber)
790 : {
791 : /* Must expand whole-row reference */
792 : RowExpr *rowexpr;
793 6 : List *fields = NIL;
794 6 : List *colnames = NIL;
795 : ListCell *lv;
796 : ListCell *ln;
797 :
798 : Assert(list_length(rte->joinaliasvars) == list_length(rte->eref->colnames));
799 48 : forboth(lv, rte->joinaliasvars, ln, rte->eref->colnames)
800 : {
801 42 : newvar = (Node *) lfirst(lv);
802 : /* Ignore dropped columns */
803 42 : if (newvar == NULL)
804 0 : continue;
805 42 : newvar = copyObject(newvar);
806 :
807 : /*
808 : * If we are expanding an alias carried down from an upper
809 : * query, must adjust its varlevelsup fields.
810 : */
811 42 : if (context->sublevels_up != 0)
812 0 : IncrementVarSublevelsUp(newvar, context->sublevels_up, 0);
813 : /* Preserve original Var's location, if possible */
814 42 : if (IsA(newvar, Var))
815 42 : ((Var *) newvar)->location = var->location;
816 : /* Recurse in case join input is itself a join */
817 : /* (also takes care of setting inserted_sublink if needed) */
818 42 : newvar = flatten_join_alias_vars_mutator(newvar, context);
819 42 : fields = lappend(fields, newvar);
820 : /* We need the names of non-dropped columns, too */
821 42 : colnames = lappend(colnames, copyObject((Node *) lfirst(ln)));
822 : }
823 6 : rowexpr = makeNode(RowExpr);
824 6 : rowexpr->args = fields;
825 6 : rowexpr->row_typeid = var->vartype;
826 6 : rowexpr->row_format = COERCE_IMPLICIT_CAST;
827 : /* vartype will always be RECORDOID, so we always need colnames */
828 6 : rowexpr->colnames = colnames;
829 6 : rowexpr->location = var->location;
830 :
831 : /* Lastly, add any varnullingrels to the replacement expression */
832 6 : return add_nullingrels_if_needed(context->root, (Node *) rowexpr,
833 : var);
834 : }
835 :
836 : /* Expand join alias reference */
837 : Assert(var->varattno > 0);
838 480 : newvar = (Node *) list_nth(rte->joinaliasvars, var->varattno - 1);
839 : Assert(newvar != NULL);
840 480 : newvar = copyObject(newvar);
841 :
842 : /*
843 : * If we are expanding an alias carried down from an upper query, must
844 : * adjust its varlevelsup fields.
845 : */
846 480 : if (context->sublevels_up != 0)
847 0 : IncrementVarSublevelsUp(newvar, context->sublevels_up, 0);
848 :
849 : /* Preserve original Var's location, if possible */
850 480 : if (IsA(newvar, Var))
851 0 : ((Var *) newvar)->location = var->location;
852 :
853 : /* Recurse in case join input is itself a join */
854 480 : newvar = flatten_join_alias_vars_mutator(newvar, context);
855 :
856 : /* Detect if we are adding a sublink to query */
857 480 : if (context->possible_sublink && !context->inserted_sublink)
858 0 : context->inserted_sublink = checkExprHasSubLink(newvar);
859 :
860 : /* Lastly, add any varnullingrels to the replacement expression */
861 480 : return add_nullingrels_if_needed(context->root, newvar, var);
862 : }
863 1765958 : if (IsA(node, PlaceHolderVar))
864 : {
865 : /* Copy the PlaceHolderVar node with correct mutation of subnodes */
866 : PlaceHolderVar *phv;
867 :
868 1744 : phv = (PlaceHolderVar *) expression_tree_mutator(node,
869 : flatten_join_alias_vars_mutator,
870 : (void *) context);
871 : /* now fix PlaceHolderVar's relid sets */
872 1744 : if (phv->phlevelsup == context->sublevels_up)
873 : {
874 1672 : phv->phrels = alias_relid_set(context->query,
875 : phv->phrels);
876 : /* we *don't* change phnullingrels */
877 : }
878 1744 : return (Node *) phv;
879 : }
880 :
881 1764214 : if (IsA(node, Query))
882 : {
883 : /* Recurse into RTE subquery or not-yet-planned sublink subquery */
884 : Query *newnode;
885 : bool save_inserted_sublink;
886 :
887 13472 : context->sublevels_up++;
888 13472 : save_inserted_sublink = context->inserted_sublink;
889 13472 : context->inserted_sublink = ((Query *) node)->hasSubLinks;
890 13472 : newnode = query_tree_mutator((Query *) node,
891 : flatten_join_alias_vars_mutator,
892 : (void *) context,
893 : QTW_IGNORE_JOINALIASES);
894 13472 : newnode->hasSubLinks |= context->inserted_sublink;
895 13472 : context->inserted_sublink = save_inserted_sublink;
896 13472 : context->sublevels_up--;
897 13472 : return (Node *) newnode;
898 : }
899 : /* Already-planned tree not supported */
900 : Assert(!IsA(node, SubPlan));
901 : Assert(!IsA(node, AlternativeSubPlan));
902 : /* Shouldn't need to handle these planner auxiliary nodes here */
903 : Assert(!IsA(node, SpecialJoinInfo));
904 : Assert(!IsA(node, PlaceHolderInfo));
905 : Assert(!IsA(node, MinMaxAggInfo));
906 :
907 1750742 : return expression_tree_mutator(node, flatten_join_alias_vars_mutator,
908 : (void *) context);
909 : }
910 :
911 : /*
912 : * flatten_group_exprs
913 : * Replace Vars that reference GROUP outputs with the underlying grouping
914 : * expressions.
915 : *
916 : * We have to preserve any varnullingrels info attached to the group Vars we're
917 : * replacing. If the replacement expression is a Var or PlaceHolderVar or
918 : * constructed from those, we can just add the varnullingrels bits to the
919 : * existing nullingrels field(s); otherwise we have to add a PlaceHolderVar
920 : * wrapper.
921 : *
922 : * NOTE: this is also used by ruleutils.c, to deparse one query parsetree back
923 : * to source text. For that use-case, root will be NULL, which is why we have
924 : * to pass the Query separately. We need the root itself only for preserving
925 : * varnullingrels. We can avoid preserving varnullingrels in the ruleutils.c's
926 : * usage because it does not make any difference to the deparsed source text.
927 : */
928 : Node *
929 9144 : flatten_group_exprs(PlannerInfo *root, Query *query, Node *node)
930 : {
931 : flatten_join_alias_vars_context context;
932 :
933 : /*
934 : * We do not expect this to be applied to the whole Query, only to
935 : * expressions or LATERAL subqueries. Hence, if the top node is a Query,
936 : * it's okay to immediately increment sublevels_up.
937 : */
938 : Assert(node != (Node *) query);
939 :
940 9144 : context.root = root;
941 9144 : context.query = query;
942 9144 : context.sublevels_up = 0;
943 : /* flag whether grouping expressions could possibly contain SubLinks */
944 9144 : context.possible_sublink = query->hasSubLinks;
945 : /* if hasSubLinks is already true, no need to work hard */
946 9144 : context.inserted_sublink = query->hasSubLinks;
947 :
948 9144 : return flatten_group_exprs_mutator(node, &context);
949 : }
950 :
951 : static Node *
952 59850 : flatten_group_exprs_mutator(Node *node,
953 : flatten_join_alias_vars_context *context)
954 : {
955 59850 : if (node == NULL)
956 10458 : return NULL;
957 49392 : if (IsA(node, Var))
958 : {
959 9478 : Var *var = (Var *) node;
960 : RangeTblEntry *rte;
961 : Node *newvar;
962 :
963 : /* No change unless Var belongs to the GROUP of the target level */
964 9478 : if (var->varlevelsup != context->sublevels_up)
965 0 : return node; /* no need to copy, really */
966 9478 : rte = rt_fetch(var->varno, context->query->rtable);
967 9478 : if (rte->rtekind != RTE_GROUP)
968 298 : return node;
969 :
970 : /* Expand group exprs reference */
971 : Assert(var->varattno > 0);
972 9180 : newvar = (Node *) list_nth(rte->groupexprs, var->varattno - 1);
973 : Assert(newvar != NULL);
974 9180 : newvar = copyObject(newvar);
975 :
976 : /*
977 : * If we are expanding an expr carried down from an upper query, must
978 : * adjust its varlevelsup fields.
979 : */
980 9180 : if (context->sublevels_up != 0)
981 0 : IncrementVarSublevelsUp(newvar, context->sublevels_up, 0);
982 :
983 : /* Preserve original Var's location, if possible */
984 9180 : if (IsA(newvar, Var))
985 7454 : ((Var *) newvar)->location = var->location;
986 :
987 : /* Detect if we are adding a sublink to query */
988 9180 : if (context->possible_sublink && !context->inserted_sublink)
989 0 : context->inserted_sublink = checkExprHasSubLink(newvar);
990 :
991 : /* Lastly, add any varnullingrels to the replacement expression */
992 9180 : return mark_nullable_by_grouping(context->root, newvar, var);
993 : }
994 :
995 39914 : if (IsA(node, Aggref))
996 : {
997 6102 : Aggref *agg = (Aggref *) node;
998 :
999 6102 : if ((int) agg->agglevelsup == context->sublevels_up)
1000 : {
1001 : /*
1002 : * If we find an aggregate call of the original level, do not
1003 : * recurse into its normal arguments, ORDER BY arguments, or
1004 : * filter; there are no grouped vars there. But we should check
1005 : * direct arguments as though they weren't in an aggregate.
1006 : */
1007 6102 : agg = copyObject(agg);
1008 6102 : agg->aggdirectargs = (List *)
1009 6102 : flatten_group_exprs_mutator((Node *) agg->aggdirectargs, context);
1010 :
1011 6102 : return (Node *) agg;
1012 : }
1013 :
1014 : /*
1015 : * We can skip recursing into aggregates of higher levels altogether,
1016 : * since they could not possibly contain Vars of concern to us (see
1017 : * transformAggregateCall). We do need to look at aggregates of lower
1018 : * levels, however.
1019 : */
1020 0 : if ((int) agg->agglevelsup > context->sublevels_up)
1021 0 : return node;
1022 : }
1023 :
1024 33812 : if (IsA(node, GroupingFunc))
1025 : {
1026 356 : GroupingFunc *grp = (GroupingFunc *) node;
1027 :
1028 : /*
1029 : * If we find a GroupingFunc node of the original or higher level, do
1030 : * not recurse into its arguments; there are no grouped vars there.
1031 : */
1032 356 : if ((int) grp->agglevelsup >= context->sublevels_up)
1033 356 : return node;
1034 : }
1035 :
1036 33456 : if (IsA(node, Query))
1037 : {
1038 : /* Recurse into RTE subquery or not-yet-planned sublink subquery */
1039 : Query *newnode;
1040 : bool save_inserted_sublink;
1041 :
1042 0 : context->sublevels_up++;
1043 0 : save_inserted_sublink = context->inserted_sublink;
1044 0 : context->inserted_sublink = ((Query *) node)->hasSubLinks;
1045 0 : newnode = query_tree_mutator((Query *) node,
1046 : flatten_group_exprs_mutator,
1047 : (void *) context,
1048 : QTW_IGNORE_GROUPEXPRS);
1049 0 : newnode->hasSubLinks |= context->inserted_sublink;
1050 0 : context->inserted_sublink = save_inserted_sublink;
1051 0 : context->sublevels_up--;
1052 0 : return (Node *) newnode;
1053 : }
1054 :
1055 33456 : return expression_tree_mutator(node, flatten_group_exprs_mutator,
1056 : (void *) context);
1057 : }
1058 :
1059 : /*
1060 : * Add oldvar's varnullingrels, if any, to a flattened grouping expression.
1061 : * The newnode has been copied, so we can modify it freely.
1062 : */
1063 : static Node *
1064 9180 : mark_nullable_by_grouping(PlannerInfo *root, Node *newnode, Var *oldvar)
1065 : {
1066 : Relids relids;
1067 :
1068 9180 : if (root == NULL)
1069 642 : return newnode;
1070 8538 : if (oldvar->varnullingrels == NULL)
1071 6840 : return newnode; /* nothing to do */
1072 :
1073 : Assert(bms_equal(oldvar->varnullingrels,
1074 : bms_make_singleton(root->group_rtindex)));
1075 :
1076 1698 : relids = pull_varnos_of_level(root, newnode, oldvar->varlevelsup);
1077 :
1078 1698 : if (!bms_is_empty(relids))
1079 : {
1080 : /*
1081 : * If the newnode is not variable-free, we set the nullingrels of Vars
1082 : * or PHVs that are contained in the expression. This is not really
1083 : * 'correct' in theory, because it is the whole expression that can be
1084 : * nullable by grouping sets, not its individual vars. But it works
1085 : * in practice, because what we need is that the expression can be
1086 : * somehow distinguished from the same expression in ECs, and marking
1087 : * its vars is sufficient for this purpose.
1088 : */
1089 1656 : newnode = add_nulling_relids(newnode,
1090 : relids,
1091 1656 : oldvar->varnullingrels);
1092 : }
1093 : else /* variable-free? */
1094 : {
1095 : /*
1096 : * If the newnode is variable-free and does not contain volatile
1097 : * functions or set-returning functions, it can be treated as a member
1098 : * of EC that is redundant. So wrap it in a new PlaceHolderVar to
1099 : * carry the nullingrels. Otherwise we do not bother to make any
1100 : * changes.
1101 : *
1102 : * Aggregate functions and window functions are not allowed in
1103 : * grouping expressions.
1104 : */
1105 : Assert(!contain_agg_clause(newnode));
1106 : Assert(!contain_window_function(newnode));
1107 :
1108 42 : if (!contain_volatile_functions(newnode) &&
1109 42 : !expression_returns_set(newnode))
1110 : {
1111 : PlaceHolderVar *newphv;
1112 : Relids phrels;
1113 :
1114 24 : phrels = get_relids_in_jointree((Node *) root->parse->jointree,
1115 : true, false);
1116 : Assert(!bms_is_empty(phrels));
1117 :
1118 24 : newphv = make_placeholder_expr(root, (Expr *) newnode, phrels);
1119 : /* newphv has zero phlevelsup and NULL phnullingrels; fix it */
1120 24 : newphv->phlevelsup = oldvar->varlevelsup;
1121 24 : newphv->phnullingrels = bms_copy(oldvar->varnullingrels);
1122 24 : newnode = (Node *) newphv;
1123 : }
1124 : }
1125 :
1126 1698 : return newnode;
1127 : }
1128 :
1129 : /*
1130 : * Add oldvar's varnullingrels, if any, to a flattened join alias expression.
1131 : * The newnode has been copied, so we can modify it freely.
1132 : */
1133 : static Node *
1134 486 : add_nullingrels_if_needed(PlannerInfo *root, Node *newnode, Var *oldvar)
1135 : {
1136 486 : if (oldvar->varnullingrels == NULL)
1137 342 : return newnode; /* nothing to do */
1138 : /* If possible, do it by adding to existing nullingrel fields */
1139 144 : if (is_standard_join_alias_expression(newnode, oldvar))
1140 132 : adjust_standard_join_alias_expression(newnode, oldvar);
1141 12 : else if (root)
1142 : {
1143 : /*
1144 : * We can insert a PlaceHolderVar to carry the nullingrels. However,
1145 : * deciding where to evaluate the PHV is slightly tricky. We first
1146 : * try to evaluate it at the natural semantic level of the new
1147 : * expression; but if that expression is variable-free, fall back to
1148 : * evaluating it at the join that the oldvar is an alias Var for.
1149 : */
1150 : PlaceHolderVar *newphv;
1151 12 : Index levelsup = oldvar->varlevelsup;
1152 12 : Relids phrels = pull_varnos_of_level(root, newnode, levelsup);
1153 :
1154 12 : if (bms_is_empty(phrels)) /* variable-free? */
1155 : {
1156 12 : if (levelsup != 0) /* this won't work otherwise */
1157 0 : elog(ERROR, "unsupported join alias expression");
1158 12 : phrels = get_relids_for_join(root->parse, oldvar->varno);
1159 : /* If it's an outer join, eval below not above the join */
1160 12 : phrels = bms_del_member(phrels, oldvar->varno);
1161 : Assert(!bms_is_empty(phrels));
1162 : }
1163 12 : newphv = make_placeholder_expr(root, (Expr *) newnode, phrels);
1164 : /* newphv has zero phlevelsup and NULL phnullingrels; fix it */
1165 12 : newphv->phlevelsup = levelsup;
1166 12 : newphv->phnullingrels = bms_copy(oldvar->varnullingrels);
1167 12 : newnode = (Node *) newphv;
1168 : }
1169 : else
1170 : {
1171 : /* ooops, we're missing support for something the parser can make */
1172 0 : elog(ERROR, "unsupported join alias expression");
1173 : }
1174 144 : return newnode;
1175 : }
1176 :
1177 : /*
1178 : * Check to see if we can insert nullingrels into this join alias expression
1179 : * without use of a separate PlaceHolderVar.
1180 : *
1181 : * This will handle Vars, PlaceHolderVars, and implicit-coercion and COALESCE
1182 : * expressions built from those. This coverage needs to handle anything
1183 : * that the parser would put into joinaliasvars.
1184 : */
1185 : static bool
1186 444 : is_standard_join_alias_expression(Node *newnode, Var *oldvar)
1187 : {
1188 444 : if (newnode == NULL)
1189 0 : return false;
1190 444 : if (IsA(newnode, Var) &&
1191 264 : ((Var *) newnode)->varlevelsup == oldvar->varlevelsup)
1192 264 : return true;
1193 180 : else if (IsA(newnode, PlaceHolderVar) &&
1194 0 : ((PlaceHolderVar *) newnode)->phlevelsup == oldvar->varlevelsup)
1195 0 : return true;
1196 180 : else if (IsA(newnode, FuncExpr))
1197 : {
1198 24 : FuncExpr *fexpr = (FuncExpr *) newnode;
1199 :
1200 : /*
1201 : * We need to assume that the function wouldn't produce non-NULL from
1202 : * NULL, which is reasonable for implicit coercions but otherwise not
1203 : * so much. (Looking at its strictness is likely overkill, and anyway
1204 : * it would cause us to fail if someone forgot to mark an implicit
1205 : * coercion as strict.)
1206 : */
1207 24 : if (fexpr->funcformat != COERCE_IMPLICIT_CAST ||
1208 24 : fexpr->args == NIL)
1209 0 : return false;
1210 :
1211 : /*
1212 : * Examine only the first argument --- coercions might have additional
1213 : * arguments that are constants.
1214 : */
1215 24 : return is_standard_join_alias_expression(linitial(fexpr->args), oldvar);
1216 : }
1217 156 : else if (IsA(newnode, RelabelType))
1218 : {
1219 12 : RelabelType *relabel = (RelabelType *) newnode;
1220 :
1221 : /* This definitely won't produce non-NULL from NULL */
1222 12 : return is_standard_join_alias_expression((Node *) relabel->arg, oldvar);
1223 : }
1224 144 : else if (IsA(newnode, CoerceViaIO))
1225 : {
1226 0 : CoerceViaIO *iocoerce = (CoerceViaIO *) newnode;
1227 :
1228 : /* This definitely won't produce non-NULL from NULL */
1229 0 : return is_standard_join_alias_expression((Node *) iocoerce->arg, oldvar);
1230 : }
1231 144 : else if (IsA(newnode, ArrayCoerceExpr))
1232 : {
1233 0 : ArrayCoerceExpr *acoerce = (ArrayCoerceExpr *) newnode;
1234 :
1235 : /* This definitely won't produce non-NULL from NULL (at array level) */
1236 0 : return is_standard_join_alias_expression((Node *) acoerce->arg, oldvar);
1237 : }
1238 144 : else if (IsA(newnode, CoalesceExpr))
1239 : {
1240 132 : CoalesceExpr *cexpr = (CoalesceExpr *) newnode;
1241 : ListCell *lc;
1242 :
1243 : Assert(cexpr->args != NIL);
1244 396 : foreach(lc, cexpr->args)
1245 : {
1246 264 : if (!is_standard_join_alias_expression(lfirst(lc), oldvar))
1247 0 : return false;
1248 : }
1249 132 : return true;
1250 : }
1251 : else
1252 12 : return false;
1253 : }
1254 :
1255 : /*
1256 : * Insert nullingrels into an expression accepted by
1257 : * is_standard_join_alias_expression.
1258 : */
1259 : static void
1260 420 : adjust_standard_join_alias_expression(Node *newnode, Var *oldvar)
1261 : {
1262 420 : if (IsA(newnode, Var) &&
1263 264 : ((Var *) newnode)->varlevelsup == oldvar->varlevelsup)
1264 264 : {
1265 264 : Var *newvar = (Var *) newnode;
1266 :
1267 264 : newvar->varnullingrels = bms_add_members(newvar->varnullingrels,
1268 264 : oldvar->varnullingrels);
1269 : }
1270 156 : else if (IsA(newnode, PlaceHolderVar) &&
1271 0 : ((PlaceHolderVar *) newnode)->phlevelsup == oldvar->varlevelsup)
1272 0 : {
1273 0 : PlaceHolderVar *newphv = (PlaceHolderVar *) newnode;
1274 :
1275 0 : newphv->phnullingrels = bms_add_members(newphv->phnullingrels,
1276 0 : oldvar->varnullingrels);
1277 : }
1278 156 : else if (IsA(newnode, FuncExpr))
1279 : {
1280 12 : FuncExpr *fexpr = (FuncExpr *) newnode;
1281 :
1282 12 : adjust_standard_join_alias_expression(linitial(fexpr->args), oldvar);
1283 : }
1284 144 : else if (IsA(newnode, RelabelType))
1285 : {
1286 12 : RelabelType *relabel = (RelabelType *) newnode;
1287 :
1288 12 : adjust_standard_join_alias_expression((Node *) relabel->arg, oldvar);
1289 : }
1290 132 : else if (IsA(newnode, CoerceViaIO))
1291 : {
1292 0 : CoerceViaIO *iocoerce = (CoerceViaIO *) newnode;
1293 :
1294 0 : adjust_standard_join_alias_expression((Node *) iocoerce->arg, oldvar);
1295 : }
1296 132 : else if (IsA(newnode, ArrayCoerceExpr))
1297 : {
1298 0 : ArrayCoerceExpr *acoerce = (ArrayCoerceExpr *) newnode;
1299 :
1300 0 : adjust_standard_join_alias_expression((Node *) acoerce->arg, oldvar);
1301 : }
1302 132 : else if (IsA(newnode, CoalesceExpr))
1303 : {
1304 132 : CoalesceExpr *cexpr = (CoalesceExpr *) newnode;
1305 : ListCell *lc;
1306 :
1307 : Assert(cexpr->args != NIL);
1308 396 : foreach(lc, cexpr->args)
1309 : {
1310 264 : adjust_standard_join_alias_expression(lfirst(lc), oldvar);
1311 : }
1312 : }
1313 : else
1314 : Assert(false);
1315 420 : }
1316 :
1317 : /*
1318 : * alias_relid_set: in a set of RT indexes, replace joins by their
1319 : * underlying base+OJ relids
1320 : */
1321 : static Relids
1322 1672 : alias_relid_set(Query *query, Relids relids)
1323 : {
1324 1672 : Relids result = NULL;
1325 : int rtindex;
1326 :
1327 1672 : rtindex = -1;
1328 4176 : while ((rtindex = bms_next_member(relids, rtindex)) >= 0)
1329 : {
1330 2504 : RangeTblEntry *rte = rt_fetch(rtindex, query->rtable);
1331 :
1332 2504 : if (rte->rtekind == RTE_JOIN)
1333 310 : result = bms_join(result, get_relids_for_join(query, rtindex));
1334 : else
1335 2194 : result = bms_add_member(result, rtindex);
1336 : }
1337 1672 : return result;
1338 : }
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