Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * rewriteManip.c
4 : *
5 : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
6 : * Portions Copyright (c) 1994, Regents of the University of California
7 : *
8 : *
9 : * IDENTIFICATION
10 : * src/backend/rewrite/rewriteManip.c
11 : *
12 : *-------------------------------------------------------------------------
13 : */
14 : #include "postgres.h"
15 :
16 : #include "catalog/pg_type.h"
17 : #include "nodes/makefuncs.h"
18 : #include "nodes/nodeFuncs.h"
19 : #include "nodes/pathnodes.h"
20 : #include "nodes/plannodes.h"
21 : #include "parser/parse_coerce.h"
22 : #include "parser/parse_relation.h"
23 : #include "parser/parsetree.h"
24 : #include "rewrite/rewriteManip.h"
25 : #include "utils/lsyscache.h"
26 :
27 :
28 : typedef struct
29 : {
30 : int sublevels_up;
31 : } contain_aggs_of_level_context;
32 :
33 : typedef struct
34 : {
35 : int agg_location;
36 : int sublevels_up;
37 : } locate_agg_of_level_context;
38 :
39 : typedef struct
40 : {
41 : int win_location;
42 : } locate_windowfunc_context;
43 :
44 : typedef struct
45 : {
46 : const Bitmapset *target_relids;
47 : const Bitmapset *added_relids;
48 : int sublevels_up;
49 : } add_nulling_relids_context;
50 :
51 : typedef struct
52 : {
53 : const Bitmapset *removable_relids;
54 : const Bitmapset *except_relids;
55 : int sublevels_up;
56 : } remove_nulling_relids_context;
57 :
58 : static bool contain_aggs_of_level_walker(Node *node,
59 : contain_aggs_of_level_context *context);
60 : static bool locate_agg_of_level_walker(Node *node,
61 : locate_agg_of_level_context *context);
62 : static bool contain_windowfuncs_walker(Node *node, void *context);
63 : static bool locate_windowfunc_walker(Node *node,
64 : locate_windowfunc_context *context);
65 : static bool checkExprHasSubLink_walker(Node *node, void *context);
66 : static Relids offset_relid_set(Relids relids, int offset);
67 : static Node *add_nulling_relids_mutator(Node *node,
68 : add_nulling_relids_context *context);
69 : static Node *remove_nulling_relids_mutator(Node *node,
70 : remove_nulling_relids_context *context);
71 :
72 :
73 : /*
74 : * contain_aggs_of_level -
75 : * Check if an expression contains an aggregate function call of a
76 : * specified query level.
77 : *
78 : * The objective of this routine is to detect whether there are aggregates
79 : * belonging to the given query level. Aggregates belonging to subqueries
80 : * or outer queries do NOT cause a true result. We must recurse into
81 : * subqueries to detect outer-reference aggregates that logically belong to
82 : * the specified query level.
83 : */
84 : bool
85 870 : contain_aggs_of_level(Node *node, int levelsup)
86 : {
87 : contain_aggs_of_level_context context;
88 :
89 870 : context.sublevels_up = levelsup;
90 :
91 : /*
92 : * Must be prepared to start with a Query or a bare expression tree; if
93 : * it's a Query, we don't want to increment sublevels_up.
94 : */
95 870 : return query_or_expression_tree_walker(node,
96 : contain_aggs_of_level_walker,
97 : &context,
98 : 0);
99 : }
100 :
101 : static bool
102 1898 : contain_aggs_of_level_walker(Node *node,
103 : contain_aggs_of_level_context *context)
104 : {
105 1898 : if (node == NULL)
106 456 : return false;
107 1442 : if (IsA(node, Aggref))
108 : {
109 54 : if (((Aggref *) node)->agglevelsup == context->sublevels_up)
110 54 : return true; /* abort the tree traversal and return true */
111 : /* else fall through to examine argument */
112 : }
113 1388 : if (IsA(node, GroupingFunc))
114 : {
115 0 : if (((GroupingFunc *) node)->agglevelsup == context->sublevels_up)
116 0 : return true;
117 : /* else fall through to examine argument */
118 : }
119 1388 : if (IsA(node, Query))
120 : {
121 : /* Recurse into subselects */
122 : bool result;
123 :
124 28 : context->sublevels_up++;
125 28 : result = query_tree_walker((Query *) node,
126 : contain_aggs_of_level_walker,
127 : context, 0);
128 28 : context->sublevels_up--;
129 28 : return result;
130 : }
131 1360 : return expression_tree_walker(node, contain_aggs_of_level_walker,
132 : context);
133 : }
134 :
135 : /*
136 : * locate_agg_of_level -
137 : * Find the parse location of any aggregate of the specified query level.
138 : *
139 : * Returns -1 if no such agg is in the querytree, or if they all have
140 : * unknown parse location. (The former case is probably caller error,
141 : * but we don't bother to distinguish it from the latter case.)
142 : *
143 : * Note: it might seem appropriate to merge this functionality into
144 : * contain_aggs_of_level, but that would complicate that function's API.
145 : * Currently, the only uses of this function are for error reporting,
146 : * and so shaving cycles probably isn't very important.
147 : */
148 : int
149 60 : locate_agg_of_level(Node *node, int levelsup)
150 : {
151 : locate_agg_of_level_context context;
152 :
153 60 : context.agg_location = -1; /* in case we find nothing */
154 60 : context.sublevels_up = levelsup;
155 :
156 : /*
157 : * Must be prepared to start with a Query or a bare expression tree; if
158 : * it's a Query, we don't want to increment sublevels_up.
159 : */
160 60 : (void) query_or_expression_tree_walker(node,
161 : locate_agg_of_level_walker,
162 : &context,
163 : 0);
164 :
165 60 : return context.agg_location;
166 : }
167 :
168 : static bool
169 240 : locate_agg_of_level_walker(Node *node,
170 : locate_agg_of_level_context *context)
171 : {
172 240 : if (node == NULL)
173 12 : return false;
174 228 : if (IsA(node, Aggref))
175 : {
176 54 : if (((Aggref *) node)->agglevelsup == context->sublevels_up &&
177 48 : ((Aggref *) node)->location >= 0)
178 : {
179 48 : context->agg_location = ((Aggref *) node)->location;
180 48 : return true; /* abort the tree traversal and return true */
181 : }
182 : /* else fall through to examine argument */
183 : }
184 180 : if (IsA(node, GroupingFunc))
185 : {
186 0 : if (((GroupingFunc *) node)->agglevelsup == context->sublevels_up &&
187 0 : ((GroupingFunc *) node)->location >= 0)
188 : {
189 0 : context->agg_location = ((GroupingFunc *) node)->location;
190 0 : return true; /* abort the tree traversal and return true */
191 : }
192 : }
193 180 : if (IsA(node, Query))
194 : {
195 : /* Recurse into subselects */
196 : bool result;
197 :
198 12 : context->sublevels_up++;
199 12 : result = query_tree_walker((Query *) node,
200 : locate_agg_of_level_walker,
201 : context, 0);
202 12 : context->sublevels_up--;
203 12 : return result;
204 : }
205 168 : return expression_tree_walker(node, locate_agg_of_level_walker, context);
206 : }
207 :
208 : /*
209 : * contain_windowfuncs -
210 : * Check if an expression contains a window function call of the
211 : * current query level.
212 : */
213 : bool
214 10250 : contain_windowfuncs(Node *node)
215 : {
216 : /*
217 : * Must be prepared to start with a Query or a bare expression tree; if
218 : * it's a Query, we don't want to increment sublevels_up.
219 : */
220 10250 : return query_or_expression_tree_walker(node,
221 : contain_windowfuncs_walker,
222 : NULL,
223 : 0);
224 : }
225 :
226 : static bool
227 11408 : contain_windowfuncs_walker(Node *node, void *context)
228 : {
229 11408 : if (node == NULL)
230 168 : return false;
231 11240 : if (IsA(node, WindowFunc))
232 18 : return true; /* abort the tree traversal and return true */
233 : /* Mustn't recurse into subselects */
234 11222 : return expression_tree_walker(node, contain_windowfuncs_walker, context);
235 : }
236 :
237 : /*
238 : * locate_windowfunc -
239 : * Find the parse location of any windowfunc of the current query level.
240 : *
241 : * Returns -1 if no such windowfunc is in the querytree, or if they all have
242 : * unknown parse location. (The former case is probably caller error,
243 : * but we don't bother to distinguish it from the latter case.)
244 : *
245 : * Note: it might seem appropriate to merge this functionality into
246 : * contain_windowfuncs, but that would complicate that function's API.
247 : * Currently, the only uses of this function are for error reporting,
248 : * and so shaving cycles probably isn't very important.
249 : */
250 : int
251 6 : locate_windowfunc(Node *node)
252 : {
253 : locate_windowfunc_context context;
254 :
255 6 : context.win_location = -1; /* in case we find nothing */
256 :
257 : /*
258 : * Must be prepared to start with a Query or a bare expression tree; if
259 : * it's a Query, we don't want to increment sublevels_up.
260 : */
261 6 : (void) query_or_expression_tree_walker(node,
262 : locate_windowfunc_walker,
263 : &context,
264 : 0);
265 :
266 6 : return context.win_location;
267 : }
268 :
269 : static bool
270 6 : locate_windowfunc_walker(Node *node, locate_windowfunc_context *context)
271 : {
272 6 : if (node == NULL)
273 0 : return false;
274 6 : if (IsA(node, WindowFunc))
275 : {
276 6 : if (((WindowFunc *) node)->location >= 0)
277 : {
278 6 : context->win_location = ((WindowFunc *) node)->location;
279 6 : return true; /* abort the tree traversal and return true */
280 : }
281 : /* else fall through to examine argument */
282 : }
283 : /* Mustn't recurse into subselects */
284 0 : return expression_tree_walker(node, locate_windowfunc_walker, context);
285 : }
286 :
287 : /*
288 : * checkExprHasSubLink -
289 : * Check if an expression contains a SubLink.
290 : */
291 : bool
292 123558 : checkExprHasSubLink(Node *node)
293 : {
294 : /*
295 : * If a Query is passed, examine it --- but we should not recurse into
296 : * sub-Queries that are in its rangetable or CTE list.
297 : */
298 123558 : return query_or_expression_tree_walker(node,
299 : checkExprHasSubLink_walker,
300 : NULL,
301 : QTW_IGNORE_RC_SUBQUERIES);
302 : }
303 :
304 : static bool
305 206960 : checkExprHasSubLink_walker(Node *node, void *context)
306 : {
307 206960 : if (node == NULL)
308 4084 : return false;
309 202876 : if (IsA(node, SubLink))
310 1844 : return true; /* abort the tree traversal and return true */
311 201032 : return expression_tree_walker(node, checkExprHasSubLink_walker, context);
312 : }
313 :
314 : /*
315 : * Check for MULTIEXPR Param within expression tree
316 : *
317 : * We intentionally don't descend into SubLinks: only Params at the current
318 : * query level are of interest.
319 : */
320 : static bool
321 192904 : contains_multiexpr_param(Node *node, void *context)
322 : {
323 192904 : if (node == NULL)
324 3384 : return false;
325 189520 : if (IsA(node, Param))
326 : {
327 486 : if (((Param *) node)->paramkind == PARAM_MULTIEXPR)
328 0 : return true; /* abort the tree traversal and return true */
329 486 : return false;
330 : }
331 189034 : return expression_tree_walker(node, contains_multiexpr_param, context);
332 : }
333 :
334 : /*
335 : * CombineRangeTables
336 : * Adds the RTEs of 'src_rtable' into 'dst_rtable'
337 : *
338 : * This also adds the RTEPermissionInfos of 'src_perminfos' (belonging to the
339 : * RTEs in 'src_rtable') into *dst_perminfos and also updates perminfoindex of
340 : * the RTEs in 'src_rtable' to now point to the perminfos' indexes in
341 : * *dst_perminfos.
342 : *
343 : * Note that this changes both 'dst_rtable' and 'dst_perminfos' destructively,
344 : * so the caller should have better passed safe-to-modify copies.
345 : */
346 : void
347 47170 : CombineRangeTables(List **dst_rtable, List **dst_perminfos,
348 : List *src_rtable, List *src_perminfos)
349 : {
350 : ListCell *l;
351 47170 : int offset = list_length(*dst_perminfos);
352 :
353 47170 : if (offset > 0)
354 : {
355 122784 : foreach(l, src_rtable)
356 : {
357 83602 : RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
358 :
359 83602 : if (rte->perminfoindex > 0)
360 35750 : rte->perminfoindex += offset;
361 : }
362 : }
363 :
364 47170 : *dst_perminfos = list_concat(*dst_perminfos, src_perminfos);
365 47170 : *dst_rtable = list_concat(*dst_rtable, src_rtable);
366 47170 : }
367 :
368 : /*
369 : * OffsetVarNodes - adjust Vars when appending one query's RT to another
370 : *
371 : * Find all Var nodes in the given tree with varlevelsup == sublevels_up,
372 : * and increment their varno fields (rangetable indexes) by 'offset'.
373 : * The varnosyn fields are adjusted similarly. Also, adjust other nodes
374 : * that contain rangetable indexes, such as RangeTblRef and JoinExpr.
375 : *
376 : * NOTE: although this has the form of a walker, we cheat and modify the
377 : * nodes in-place. The given expression tree should have been copied
378 : * earlier to ensure that no unwanted side-effects occur!
379 : */
380 :
381 : typedef struct
382 : {
383 : int offset;
384 : int sublevels_up;
385 : } OffsetVarNodes_context;
386 :
387 : static bool
388 2316380 : OffsetVarNodes_walker(Node *node, OffsetVarNodes_context *context)
389 : {
390 2316380 : if (node == NULL)
391 696380 : return false;
392 1620000 : if (IsA(node, Var))
393 : {
394 870528 : Var *var = (Var *) node;
395 :
396 870528 : if (var->varlevelsup == context->sublevels_up)
397 : {
398 845002 : var->varno += context->offset;
399 845002 : var->varnullingrels = offset_relid_set(var->varnullingrels,
400 : context->offset);
401 845002 : if (var->varnosyn > 0)
402 845002 : var->varnosyn += context->offset;
403 : }
404 870528 : return false;
405 : }
406 749472 : if (IsA(node, CurrentOfExpr))
407 : {
408 0 : CurrentOfExpr *cexpr = (CurrentOfExpr *) node;
409 :
410 0 : if (context->sublevels_up == 0)
411 0 : cexpr->cvarno += context->offset;
412 0 : return false;
413 : }
414 749472 : if (IsA(node, RangeTblRef))
415 : {
416 66130 : RangeTblRef *rtr = (RangeTblRef *) node;
417 :
418 66130 : if (context->sublevels_up == 0)
419 60174 : rtr->rtindex += context->offset;
420 : /* the subquery itself is visited separately */
421 66130 : return false;
422 : }
423 683342 : if (IsA(node, JoinExpr))
424 : {
425 16078 : JoinExpr *j = (JoinExpr *) node;
426 :
427 16078 : if (j->rtindex && context->sublevels_up == 0)
428 15090 : j->rtindex += context->offset;
429 : /* fall through to examine children */
430 : }
431 683342 : if (IsA(node, PlaceHolderVar))
432 : {
433 470 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
434 :
435 470 : if (phv->phlevelsup == context->sublevels_up)
436 : {
437 362 : phv->phrels = offset_relid_set(phv->phrels,
438 : context->offset);
439 362 : phv->phnullingrels = offset_relid_set(phv->phnullingrels,
440 : context->offset);
441 : }
442 : /* fall through to examine children */
443 : }
444 683342 : if (IsA(node, AppendRelInfo))
445 : {
446 1068 : AppendRelInfo *appinfo = (AppendRelInfo *) node;
447 :
448 1068 : if (context->sublevels_up == 0)
449 : {
450 1068 : appinfo->parent_relid += context->offset;
451 1068 : appinfo->child_relid += context->offset;
452 : }
453 : /* fall through to examine children */
454 : }
455 : /* Shouldn't need to handle other planner auxiliary nodes here */
456 : Assert(!IsA(node, PlanRowMark));
457 : Assert(!IsA(node, SpecialJoinInfo));
458 : Assert(!IsA(node, PlaceHolderInfo));
459 : Assert(!IsA(node, MinMaxAggInfo));
460 :
461 683342 : if (IsA(node, Query))
462 : {
463 : /* Recurse into subselects */
464 : bool result;
465 :
466 5280 : context->sublevels_up++;
467 5280 : result = query_tree_walker((Query *) node, OffsetVarNodes_walker,
468 : context, 0);
469 5280 : context->sublevels_up--;
470 5280 : return result;
471 : }
472 678062 : return expression_tree_walker(node, OffsetVarNodes_walker, context);
473 : }
474 :
475 : void
476 84832 : OffsetVarNodes(Node *node, int offset, int sublevels_up)
477 : {
478 : OffsetVarNodes_context context;
479 :
480 84832 : context.offset = offset;
481 84832 : context.sublevels_up = sublevels_up;
482 :
483 : /*
484 : * Must be prepared to start with a Query or a bare expression tree; if
485 : * it's a Query, go straight to query_tree_walker to make sure that
486 : * sublevels_up doesn't get incremented prematurely.
487 : */
488 84832 : if (node && IsA(node, Query))
489 42416 : {
490 42416 : Query *qry = (Query *) node;
491 :
492 : /*
493 : * If we are starting at a Query, and sublevels_up is zero, then we
494 : * must also fix rangetable indexes in the Query itself --- namely
495 : * resultRelation, mergeTargetRelation, exclRelIndex and rowMarks
496 : * entries. sublevels_up cannot be zero when recursing into a
497 : * subquery, so there's no need to have the same logic inside
498 : * OffsetVarNodes_walker.
499 : */
500 42416 : if (sublevels_up == 0)
501 : {
502 : ListCell *l;
503 :
504 42416 : if (qry->resultRelation)
505 1272 : qry->resultRelation += offset;
506 :
507 42416 : if (qry->mergeTargetRelation)
508 0 : qry->mergeTargetRelation += offset;
509 :
510 42416 : if (qry->onConflict && qry->onConflict->exclRelIndex)
511 36 : qry->onConflict->exclRelIndex += offset;
512 :
513 42564 : foreach(l, qry->rowMarks)
514 : {
515 148 : RowMarkClause *rc = (RowMarkClause *) lfirst(l);
516 :
517 148 : rc->rti += offset;
518 : }
519 : }
520 42416 : query_tree_walker(qry, OffsetVarNodes_walker, &context, 0);
521 : }
522 : else
523 42416 : OffsetVarNodes_walker(node, &context);
524 84832 : }
525 :
526 : static Relids
527 845726 : offset_relid_set(Relids relids, int offset)
528 : {
529 845726 : Relids result = NULL;
530 : int rtindex;
531 :
532 845726 : rtindex = -1;
533 981556 : while ((rtindex = bms_next_member(relids, rtindex)) >= 0)
534 135830 : result = bms_add_member(result, rtindex + offset);
535 845726 : return result;
536 : }
537 :
538 : /*
539 : * ChangeVarNodes - adjust Var nodes for a specific change of RT index
540 : *
541 : * Find all Var nodes in the given tree belonging to a specific relation
542 : * (identified by sublevels_up and rt_index), and change their varno fields
543 : * to 'new_index'. The varnosyn fields are changed too. Also, adjust other
544 : * nodes that contain rangetable indexes, such as RangeTblRef and JoinExpr.
545 : *
546 : * NOTE: although this has the form of a walker, we cheat and modify the
547 : * nodes in-place. The given expression tree should have been copied
548 : * earlier to ensure that no unwanted side-effects occur!
549 : */
550 :
551 : static bool
552 351962 : ChangeVarNodes_walker(Node *node, ChangeVarNodes_context *context)
553 : {
554 351962 : if (node == NULL)
555 119634 : return false;
556 :
557 232328 : if (context->callback && context->callback(node, context))
558 4388 : return false;
559 :
560 227940 : if (IsA(node, Var))
561 : {
562 72288 : Var *var = (Var *) node;
563 :
564 72288 : if (var->varlevelsup == context->sublevels_up)
565 : {
566 69126 : if (var->varno == context->rt_index)
567 44976 : var->varno = context->new_index;
568 69126 : var->varnullingrels = adjust_relid_set(var->varnullingrels,
569 : context->rt_index,
570 : context->new_index);
571 69126 : if (var->varnosyn == context->rt_index)
572 44976 : var->varnosyn = context->new_index;
573 : }
574 72288 : return false;
575 : }
576 155652 : if (IsA(node, CurrentOfExpr))
577 : {
578 0 : CurrentOfExpr *cexpr = (CurrentOfExpr *) node;
579 :
580 0 : if (context->sublevels_up == 0 &&
581 0 : cexpr->cvarno == context->rt_index)
582 0 : cexpr->cvarno = context->new_index;
583 0 : return false;
584 : }
585 155652 : if (IsA(node, RangeTblRef))
586 : {
587 5374 : RangeTblRef *rtr = (RangeTblRef *) node;
588 :
589 5374 : if (context->sublevels_up == 0 &&
590 3262 : rtr->rtindex == context->rt_index)
591 1712 : rtr->rtindex = context->new_index;
592 : /* the subquery itself is visited separately */
593 5374 : return false;
594 : }
595 150278 : if (IsA(node, JoinExpr))
596 : {
597 722 : JoinExpr *j = (JoinExpr *) node;
598 :
599 722 : if (context->sublevels_up == 0 &&
600 722 : j->rtindex == context->rt_index)
601 0 : j->rtindex = context->new_index;
602 : /* fall through to examine children */
603 : }
604 150278 : if (IsA(node, PlaceHolderVar))
605 : {
606 96 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
607 :
608 96 : if (phv->phlevelsup == context->sublevels_up)
609 : {
610 96 : phv->phrels = adjust_relid_set(phv->phrels,
611 : context->rt_index,
612 : context->new_index);
613 96 : phv->phnullingrels = adjust_relid_set(phv->phnullingrels,
614 : context->rt_index,
615 : context->new_index);
616 : }
617 : /* fall through to examine children */
618 : }
619 150278 : if (IsA(node, PlanRowMark))
620 : {
621 0 : PlanRowMark *rowmark = (PlanRowMark *) node;
622 :
623 0 : if (context->sublevels_up == 0)
624 : {
625 0 : if (rowmark->rti == context->rt_index)
626 0 : rowmark->rti = context->new_index;
627 0 : if (rowmark->prti == context->rt_index)
628 0 : rowmark->prti = context->new_index;
629 : }
630 0 : return false;
631 : }
632 150278 : if (IsA(node, AppendRelInfo))
633 : {
634 0 : AppendRelInfo *appinfo = (AppendRelInfo *) node;
635 :
636 0 : if (context->sublevels_up == 0)
637 : {
638 0 : if (appinfo->parent_relid == context->rt_index)
639 0 : appinfo->parent_relid = context->new_index;
640 0 : if (appinfo->child_relid == context->rt_index)
641 0 : appinfo->child_relid = context->new_index;
642 : }
643 : /* fall through to examine children */
644 : }
645 : /* Shouldn't need to handle other planner auxiliary nodes here */
646 : Assert(!IsA(node, SpecialJoinInfo));
647 : Assert(!IsA(node, PlaceHolderInfo));
648 : Assert(!IsA(node, MinMaxAggInfo));
649 :
650 150278 : if (IsA(node, Query))
651 : {
652 : /* Recurse into subselects */
653 : bool result;
654 :
655 2430 : context->sublevels_up++;
656 2430 : result = query_tree_walker((Query *) node, ChangeVarNodes_walker,
657 : context, 0);
658 2430 : context->sublevels_up--;
659 2430 : return result;
660 : }
661 147848 : return expression_tree_walker(node, ChangeVarNodes_walker, context);
662 : }
663 :
664 : /*
665 : * ChangeVarNodesExtended - similar to ChangeVarNodes, but with an additional
666 : * 'callback' param
667 : *
668 : * ChangeVarNodes changes a given node and all of its underlying nodes. This
669 : * version of function additionally takes a callback, which has a chance to
670 : * process a node before ChangeVarNodes_walker. A callback returns a boolean
671 : * value indicating if the given node should be skipped from further processing
672 : * by ChangeVarNodes_walker. The callback is called only for expressions and
673 : * other children nodes of a Query processed by a walker. Initial processing
674 : * of the root Query doesn't involve the callback.
675 : */
676 : void
677 38230 : ChangeVarNodesExtended(Node *node, int rt_index, int new_index,
678 : int sublevels_up, ChangeVarNodes_callback callback)
679 : {
680 : ChangeVarNodes_context context;
681 :
682 38230 : context.rt_index = rt_index;
683 38230 : context.new_index = new_index;
684 38230 : context.sublevels_up = sublevels_up;
685 38230 : context.callback = callback;
686 :
687 : /*
688 : * Must be prepared to start with a Query or a bare expression tree; if
689 : * it's a Query, go straight to query_tree_walker to make sure that
690 : * sublevels_up doesn't get incremented prematurely.
691 : */
692 38230 : if (node && IsA(node, Query))
693 5216 : {
694 5216 : Query *qry = (Query *) node;
695 :
696 : /*
697 : * If we are starting at a Query, and sublevels_up is zero, then we
698 : * must also fix rangetable indexes in the Query itself --- namely
699 : * resultRelation, mergeTargetRelation, exclRelIndex and rowMarks
700 : * entries. sublevels_up cannot be zero when recursing into a
701 : * subquery, so there's no need to have the same logic inside
702 : * ChangeVarNodes_walker.
703 : */
704 5216 : if (sublevels_up == 0)
705 : {
706 : ListCell *l;
707 :
708 5216 : if (qry->resultRelation == rt_index)
709 3230 : qry->resultRelation = new_index;
710 :
711 5216 : if (qry->mergeTargetRelation == rt_index)
712 852 : qry->mergeTargetRelation = new_index;
713 :
714 : /* this is unlikely to ever be used, but ... */
715 5216 : if (qry->onConflict && qry->onConflict->exclRelIndex == rt_index)
716 0 : qry->onConflict->exclRelIndex = new_index;
717 :
718 5400 : foreach(l, qry->rowMarks)
719 : {
720 184 : RowMarkClause *rc = (RowMarkClause *) lfirst(l);
721 :
722 184 : if (rc->rti == rt_index)
723 68 : rc->rti = new_index;
724 : }
725 : }
726 5216 : query_tree_walker(qry, ChangeVarNodes_walker, &context, 0);
727 : }
728 : else
729 33014 : ChangeVarNodes_walker(node, &context);
730 38230 : }
731 :
732 : void
733 26734 : ChangeVarNodes(Node *node, int rt_index, int new_index, int sublevels_up)
734 : {
735 26734 : ChangeVarNodesExtended(node, rt_index, new_index, sublevels_up, NULL);
736 26734 : }
737 :
738 : /*
739 : * ChangeVarNodesWalkExpression - process expression within the custom
740 : * callback provided to the
741 : * ChangeVarNodesExtended.
742 : */
743 : bool
744 3552 : ChangeVarNodesWalkExpression(Node *node, ChangeVarNodes_context *context)
745 : {
746 3552 : return expression_tree_walker(node,
747 : ChangeVarNodes_walker,
748 : (void *) context);
749 : }
750 :
751 : /*
752 : * adjust_relid_set - substitute newrelid for oldrelid in a Relid set
753 : *
754 : * Attempt to remove oldrelid from a Relid set (as long as it's not a special
755 : * varno). If oldrelid was found and removed, insert newrelid into a Relid
756 : * set (as long as it's not a special varno). Therefore, when oldrelid is
757 : * a special varno, this function does nothing. When newrelid is a special
758 : * varno, this function behaves as delete.
759 : */
760 : Relids
761 245074 : adjust_relid_set(Relids relids, int oldrelid, int newrelid)
762 : {
763 245074 : if (!IS_SPECIAL_VARNO(oldrelid) && bms_is_member(oldrelid, relids))
764 : {
765 : /* Ensure we have a modifiable copy */
766 91142 : relids = bms_copy(relids);
767 : /* Remove old, add new */
768 91142 : relids = bms_del_member(relids, oldrelid);
769 91142 : if (!IS_SPECIAL_VARNO(newrelid))
770 9926 : relids = bms_add_member(relids, newrelid);
771 : }
772 245074 : return relids;
773 : }
774 :
775 : /*
776 : * IncrementVarSublevelsUp - adjust Var nodes when pushing them down in tree
777 : *
778 : * Find all Var nodes in the given tree having varlevelsup >= min_sublevels_up,
779 : * and add delta_sublevels_up to their varlevelsup value. This is needed when
780 : * an expression that's correct for some nesting level is inserted into a
781 : * subquery. Ordinarily the initial call has min_sublevels_up == 0 so that
782 : * all Vars are affected. The point of min_sublevels_up is that we can
783 : * increment it when we recurse into a sublink, so that local variables in
784 : * that sublink are not affected, only outer references to vars that belong
785 : * to the expression's original query level or parents thereof.
786 : *
787 : * Likewise for other nodes containing levelsup fields, such as Aggref.
788 : *
789 : * NOTE: although this has the form of a walker, we cheat and modify the
790 : * Var nodes in-place. The given expression tree should have been copied
791 : * earlier to ensure that no unwanted side-effects occur!
792 : */
793 :
794 : typedef struct
795 : {
796 : int delta_sublevels_up;
797 : int min_sublevels_up;
798 : } IncrementVarSublevelsUp_context;
799 :
800 : static bool
801 3293226 : IncrementVarSublevelsUp_walker(Node *node,
802 : IncrementVarSublevelsUp_context *context)
803 : {
804 3293226 : if (node == NULL)
805 944302 : return false;
806 2348924 : if (IsA(node, Var))
807 : {
808 1194526 : Var *var = (Var *) node;
809 :
810 1194526 : if (var->varlevelsup >= context->min_sublevels_up)
811 10698 : var->varlevelsup += context->delta_sublevels_up;
812 1194526 : return false; /* done here */
813 : }
814 1154398 : if (IsA(node, CurrentOfExpr))
815 : {
816 : /* this should not happen */
817 0 : if (context->min_sublevels_up == 0)
818 0 : elog(ERROR, "cannot push down CurrentOfExpr");
819 0 : return false;
820 : }
821 1154398 : if (IsA(node, Aggref))
822 : {
823 2734 : Aggref *agg = (Aggref *) node;
824 :
825 2734 : if (agg->agglevelsup >= context->min_sublevels_up)
826 82 : agg->agglevelsup += context->delta_sublevels_up;
827 : /* fall through to recurse into argument */
828 : }
829 1154398 : if (IsA(node, GroupingFunc))
830 : {
831 64 : GroupingFunc *grp = (GroupingFunc *) node;
832 :
833 64 : if (grp->agglevelsup >= context->min_sublevels_up)
834 64 : grp->agglevelsup += context->delta_sublevels_up;
835 : /* fall through to recurse into argument */
836 : }
837 1154398 : if (IsA(node, PlaceHolderVar))
838 : {
839 904 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
840 :
841 904 : if (phv->phlevelsup >= context->min_sublevels_up)
842 542 : phv->phlevelsup += context->delta_sublevels_up;
843 : /* fall through to recurse into argument */
844 : }
845 1154398 : if (IsA(node, ReturningExpr))
846 : {
847 144 : ReturningExpr *rexpr = (ReturningExpr *) node;
848 :
849 144 : if (rexpr->retlevelsup >= context->min_sublevels_up)
850 144 : rexpr->retlevelsup += context->delta_sublevels_up;
851 : /* fall through to recurse into argument */
852 : }
853 1154398 : if (IsA(node, RangeTblEntry))
854 : {
855 129632 : RangeTblEntry *rte = (RangeTblEntry *) node;
856 :
857 129632 : if (rte->rtekind == RTE_CTE)
858 : {
859 6314 : if (rte->ctelevelsup >= context->min_sublevels_up)
860 6284 : rte->ctelevelsup += context->delta_sublevels_up;
861 : }
862 129632 : return false; /* allow range_table_walker to continue */
863 : }
864 1024766 : if (IsA(node, Query))
865 : {
866 : /* Recurse into subselects */
867 : bool result;
868 :
869 22004 : context->min_sublevels_up++;
870 22004 : result = query_tree_walker((Query *) node,
871 : IncrementVarSublevelsUp_walker,
872 : context,
873 : QTW_EXAMINE_RTES_BEFORE);
874 22004 : context->min_sublevels_up--;
875 22004 : return result;
876 : }
877 1002762 : return expression_tree_walker(node, IncrementVarSublevelsUp_walker, context);
878 : }
879 :
880 : void
881 89088 : IncrementVarSublevelsUp(Node *node, int delta_sublevels_up,
882 : int min_sublevels_up)
883 : {
884 : IncrementVarSublevelsUp_context context;
885 :
886 89088 : context.delta_sublevels_up = delta_sublevels_up;
887 89088 : context.min_sublevels_up = min_sublevels_up;
888 :
889 : /*
890 : * Must be prepared to start with a Query or a bare expression tree; if
891 : * it's a Query, we don't want to increment sublevels_up.
892 : */
893 89088 : query_or_expression_tree_walker(node,
894 : IncrementVarSublevelsUp_walker,
895 : &context,
896 : QTW_EXAMINE_RTES_BEFORE);
897 89088 : }
898 :
899 : /*
900 : * IncrementVarSublevelsUp_rtable -
901 : * Same as IncrementVarSublevelsUp, but to be invoked on a range table.
902 : */
903 : void
904 4804 : IncrementVarSublevelsUp_rtable(List *rtable, int delta_sublevels_up,
905 : int min_sublevels_up)
906 : {
907 : IncrementVarSublevelsUp_context context;
908 :
909 4804 : context.delta_sublevels_up = delta_sublevels_up;
910 4804 : context.min_sublevels_up = min_sublevels_up;
911 :
912 4804 : range_table_walker(rtable,
913 : IncrementVarSublevelsUp_walker,
914 : &context,
915 : QTW_EXAMINE_RTES_BEFORE);
916 4804 : }
917 :
918 : /*
919 : * SetVarReturningType - adjust Var nodes for a specified varreturningtype.
920 : *
921 : * Find all Var nodes referring to the specified result relation in the given
922 : * expression and set their varreturningtype to the specified value.
923 : *
924 : * NOTE: although this has the form of a walker, we cheat and modify the
925 : * Var nodes in-place. The given expression tree should have been copied
926 : * earlier to ensure that no unwanted side-effects occur!
927 : */
928 :
929 : typedef struct
930 : {
931 : int result_relation;
932 : int sublevels_up;
933 : VarReturningType returning_type;
934 : } SetVarReturningType_context;
935 :
936 : static bool
937 2154 : SetVarReturningType_walker(Node *node, SetVarReturningType_context *context)
938 : {
939 2154 : if (node == NULL)
940 576 : return false;
941 1578 : if (IsA(node, Var))
942 : {
943 978 : Var *var = (Var *) node;
944 :
945 978 : if (var->varno == context->result_relation &&
946 918 : var->varlevelsup == context->sublevels_up)
947 918 : var->varreturningtype = context->returning_type;
948 :
949 978 : return false;
950 : }
951 :
952 600 : if (IsA(node, Query))
953 : {
954 : /* Recurse into subselects */
955 : bool result;
956 :
957 48 : context->sublevels_up++;
958 48 : result = query_tree_walker((Query *) node, SetVarReturningType_walker,
959 : context, 0);
960 48 : context->sublevels_up--;
961 48 : return result;
962 : }
963 552 : return expression_tree_walker(node, SetVarReturningType_walker, context);
964 : }
965 :
966 : static void
967 1170 : SetVarReturningType(Node *node, int result_relation, int sublevels_up,
968 : VarReturningType returning_type)
969 : {
970 : SetVarReturningType_context context;
971 :
972 1170 : context.result_relation = result_relation;
973 1170 : context.sublevels_up = sublevels_up;
974 1170 : context.returning_type = returning_type;
975 :
976 : /* Expect to start with an expression */
977 1170 : SetVarReturningType_walker(node, &context);
978 1170 : }
979 :
980 : /*
981 : * rangeTableEntry_used - detect whether an RTE is referenced somewhere
982 : * in var nodes or join or setOp trees of a query or expression.
983 : */
984 :
985 : typedef struct
986 : {
987 : int rt_index;
988 : int sublevels_up;
989 : } rangeTableEntry_used_context;
990 :
991 : static bool
992 4080796 : rangeTableEntry_used_walker(Node *node,
993 : rangeTableEntry_used_context *context)
994 : {
995 4080796 : if (node == NULL)
996 737640 : return false;
997 3343156 : if (IsA(node, Var))
998 : {
999 966800 : Var *var = (Var *) node;
1000 :
1001 966800 : if (var->varlevelsup == context->sublevels_up &&
1002 1543734 : (var->varno == context->rt_index ||
1003 614192 : bms_is_member(context->rt_index, var->varnullingrels)))
1004 315350 : return true;
1005 651450 : return false;
1006 : }
1007 2376356 : if (IsA(node, CurrentOfExpr))
1008 : {
1009 12 : CurrentOfExpr *cexpr = (CurrentOfExpr *) node;
1010 :
1011 12 : if (context->sublevels_up == 0 &&
1012 12 : cexpr->cvarno == context->rt_index)
1013 0 : return true;
1014 12 : return false;
1015 : }
1016 2376344 : if (IsA(node, RangeTblRef))
1017 : {
1018 136346 : RangeTblRef *rtr = (RangeTblRef *) node;
1019 :
1020 136346 : if (rtr->rtindex == context->rt_index &&
1021 71860 : context->sublevels_up == 0)
1022 68992 : return true;
1023 : /* the subquery itself is visited separately */
1024 67354 : return false;
1025 : }
1026 2239998 : if (IsA(node, JoinExpr))
1027 : {
1028 47574 : JoinExpr *j = (JoinExpr *) node;
1029 :
1030 47574 : if (j->rtindex == context->rt_index &&
1031 78 : context->sublevels_up == 0)
1032 0 : return true;
1033 : /* fall through to examine children */
1034 : }
1035 : /* Shouldn't need to handle planner auxiliary nodes here */
1036 : Assert(!IsA(node, PlaceHolderVar));
1037 : Assert(!IsA(node, PlanRowMark));
1038 : Assert(!IsA(node, SpecialJoinInfo));
1039 : Assert(!IsA(node, AppendRelInfo));
1040 : Assert(!IsA(node, PlaceHolderInfo));
1041 : Assert(!IsA(node, MinMaxAggInfo));
1042 :
1043 2239998 : if (IsA(node, Query))
1044 : {
1045 : /* Recurse into subselects */
1046 : bool result;
1047 :
1048 15742 : context->sublevels_up++;
1049 15742 : result = query_tree_walker((Query *) node, rangeTableEntry_used_walker,
1050 : context, 0);
1051 15742 : context->sublevels_up--;
1052 15742 : return result;
1053 : }
1054 2224256 : return expression_tree_walker(node, rangeTableEntry_used_walker, context);
1055 : }
1056 :
1057 : bool
1058 399942 : rangeTableEntry_used(Node *node, int rt_index, int sublevels_up)
1059 : {
1060 : rangeTableEntry_used_context context;
1061 :
1062 399942 : context.rt_index = rt_index;
1063 399942 : context.sublevels_up = sublevels_up;
1064 :
1065 : /*
1066 : * Must be prepared to start with a Query or a bare expression tree; if
1067 : * it's a Query, we don't want to increment sublevels_up.
1068 : */
1069 399942 : return query_or_expression_tree_walker(node,
1070 : rangeTableEntry_used_walker,
1071 : &context,
1072 : 0);
1073 : }
1074 :
1075 :
1076 : /*
1077 : * If the given Query is an INSERT ... SELECT construct, extract and
1078 : * return the sub-Query node that represents the SELECT part. Otherwise
1079 : * return the given Query.
1080 : *
1081 : * If subquery_ptr is not NULL, then *subquery_ptr is set to the location
1082 : * of the link to the SELECT subquery inside parsetree, or NULL if not an
1083 : * INSERT ... SELECT.
1084 : *
1085 : * This is a hack needed because transformations on INSERT ... SELECTs that
1086 : * appear in rule actions should be applied to the source SELECT, not to the
1087 : * INSERT part. Perhaps this can be cleaned up with redesigned querytrees.
1088 : */
1089 : Query *
1090 3532 : getInsertSelectQuery(Query *parsetree, Query ***subquery_ptr)
1091 : {
1092 : Query *selectquery;
1093 : RangeTblEntry *selectrte;
1094 : RangeTblRef *rtr;
1095 :
1096 3532 : if (subquery_ptr)
1097 1386 : *subquery_ptr = NULL;
1098 :
1099 3532 : if (parsetree == NULL)
1100 0 : return parsetree;
1101 3532 : if (parsetree->commandType != CMD_INSERT)
1102 1550 : return parsetree;
1103 :
1104 : /*
1105 : * Currently, this is ONLY applied to rule-action queries, and so we
1106 : * expect to find the OLD and NEW placeholder entries in the given query.
1107 : * If they're not there, it must be an INSERT/SELECT in which they've been
1108 : * pushed down to the SELECT.
1109 : */
1110 1982 : if (list_length(parsetree->rtable) >= 2 &&
1111 1982 : strcmp(rt_fetch(PRS2_OLD_VARNO, parsetree->rtable)->eref->aliasname,
1112 1806 : "old") == 0 &&
1113 1806 : strcmp(rt_fetch(PRS2_NEW_VARNO, parsetree->rtable)->eref->aliasname,
1114 : "new") == 0)
1115 1806 : return parsetree;
1116 : Assert(parsetree->jointree && IsA(parsetree->jointree, FromExpr));
1117 176 : if (list_length(parsetree->jointree->fromlist) != 1)
1118 0 : elog(ERROR, "expected to find SELECT subquery");
1119 176 : rtr = (RangeTblRef *) linitial(parsetree->jointree->fromlist);
1120 176 : if (!IsA(rtr, RangeTblRef))
1121 0 : elog(ERROR, "expected to find SELECT subquery");
1122 176 : selectrte = rt_fetch(rtr->rtindex, parsetree->rtable);
1123 176 : if (!(selectrte->rtekind == RTE_SUBQUERY &&
1124 176 : selectrte->subquery &&
1125 176 : IsA(selectrte->subquery, Query) &&
1126 176 : selectrte->subquery->commandType == CMD_SELECT))
1127 0 : elog(ERROR, "expected to find SELECT subquery");
1128 176 : selectquery = selectrte->subquery;
1129 176 : if (list_length(selectquery->rtable) >= 2 &&
1130 176 : strcmp(rt_fetch(PRS2_OLD_VARNO, selectquery->rtable)->eref->aliasname,
1131 176 : "old") == 0 &&
1132 176 : strcmp(rt_fetch(PRS2_NEW_VARNO, selectquery->rtable)->eref->aliasname,
1133 : "new") == 0)
1134 : {
1135 176 : if (subquery_ptr)
1136 60 : *subquery_ptr = &(selectrte->subquery);
1137 176 : return selectquery;
1138 : }
1139 0 : elog(ERROR, "could not find rule placeholders");
1140 : return NULL; /* not reached */
1141 : }
1142 :
1143 :
1144 : /*
1145 : * Add the given qualifier condition to the query's WHERE clause
1146 : */
1147 : void
1148 3728 : AddQual(Query *parsetree, Node *qual)
1149 : {
1150 : Node *copy;
1151 :
1152 3728 : if (qual == NULL)
1153 1740 : return;
1154 :
1155 1988 : if (parsetree->commandType == CMD_UTILITY)
1156 : {
1157 : /*
1158 : * There's noplace to put the qual on a utility statement.
1159 : *
1160 : * If it's a NOTIFY, silently ignore the qual; this means that the
1161 : * NOTIFY will execute, whether or not there are any qualifying rows.
1162 : * While clearly wrong, this is much more useful than refusing to
1163 : * execute the rule at all, and extra NOTIFY events are harmless for
1164 : * typical uses of NOTIFY.
1165 : *
1166 : * If it isn't a NOTIFY, error out, since unconditional execution of
1167 : * other utility stmts is unlikely to be wanted. (This case is not
1168 : * currently allowed anyway, but keep the test for safety.)
1169 : */
1170 0 : if (parsetree->utilityStmt && IsA(parsetree->utilityStmt, NotifyStmt))
1171 0 : return;
1172 : else
1173 0 : ereport(ERROR,
1174 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1175 : errmsg("conditional utility statements are not implemented")));
1176 : }
1177 :
1178 1988 : if (parsetree->setOperations != NULL)
1179 : {
1180 : /*
1181 : * There's noplace to put the qual on a setop statement, either. (This
1182 : * could be fixed, but right now the planner simply ignores any qual
1183 : * condition on a setop query.)
1184 : */
1185 0 : ereport(ERROR,
1186 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1187 : errmsg("conditional UNION/INTERSECT/EXCEPT statements are not implemented")));
1188 : }
1189 :
1190 : /* INTERSECT wants the original, but we need to copy - Jan */
1191 1988 : copy = copyObject(qual);
1192 :
1193 1988 : parsetree->jointree->quals = make_and_qual(parsetree->jointree->quals,
1194 : copy);
1195 :
1196 : /*
1197 : * We had better not have stuck an aggregate into the WHERE clause.
1198 : */
1199 : Assert(!contain_aggs_of_level(copy, 0));
1200 :
1201 : /*
1202 : * Make sure query is marked correctly if added qual has sublinks. Need
1203 : * not search qual when query is already marked.
1204 : */
1205 1988 : if (!parsetree->hasSubLinks)
1206 1946 : parsetree->hasSubLinks = checkExprHasSubLink(copy);
1207 : }
1208 :
1209 :
1210 : /*
1211 : * Invert the given clause and add it to the WHERE qualifications of the
1212 : * given querytree. Inversion means "x IS NOT TRUE", not just "NOT x",
1213 : * else we will do the wrong thing when x evaluates to NULL.
1214 : */
1215 : void
1216 444 : AddInvertedQual(Query *parsetree, Node *qual)
1217 : {
1218 : BooleanTest *invqual;
1219 :
1220 444 : if (qual == NULL)
1221 0 : return;
1222 :
1223 : /* Need not copy input qual, because AddQual will... */
1224 444 : invqual = makeNode(BooleanTest);
1225 444 : invqual->arg = (Expr *) qual;
1226 444 : invqual->booltesttype = IS_NOT_TRUE;
1227 444 : invqual->location = -1;
1228 :
1229 444 : AddQual(parsetree, (Node *) invqual);
1230 : }
1231 :
1232 :
1233 : /*
1234 : * add_nulling_relids() finds Vars and PlaceHolderVars that belong to any
1235 : * of the target_relids, and adds added_relids to their varnullingrels
1236 : * and phnullingrels fields. If target_relids is NULL, all level-zero
1237 : * Vars and PHVs are modified.
1238 : */
1239 : Node *
1240 8140 : add_nulling_relids(Node *node,
1241 : const Bitmapset *target_relids,
1242 : const Bitmapset *added_relids)
1243 : {
1244 : add_nulling_relids_context context;
1245 :
1246 8140 : context.target_relids = target_relids;
1247 8140 : context.added_relids = added_relids;
1248 8140 : context.sublevels_up = 0;
1249 8140 : return query_or_expression_tree_mutator(node,
1250 : add_nulling_relids_mutator,
1251 : &context,
1252 : 0);
1253 : }
1254 :
1255 : static Node *
1256 36162 : add_nulling_relids_mutator(Node *node,
1257 : add_nulling_relids_context *context)
1258 : {
1259 36162 : if (node == NULL)
1260 1110 : return NULL;
1261 35052 : if (IsA(node, Var))
1262 : {
1263 13454 : Var *var = (Var *) node;
1264 :
1265 13454 : if (var->varlevelsup == context->sublevels_up &&
1266 26692 : (context->target_relids == NULL ||
1267 13244 : bms_is_member(var->varno, context->target_relids)))
1268 : {
1269 7332 : Relids newnullingrels = bms_union(var->varnullingrels,
1270 : context->added_relids);
1271 :
1272 : /* Copy the Var ... */
1273 7332 : var = copyObject(var);
1274 : /* ... and replace the copy's varnullingrels field */
1275 7332 : var->varnullingrels = newnullingrels;
1276 7332 : return (Node *) var;
1277 : }
1278 : /* Otherwise fall through to copy the Var normally */
1279 : }
1280 21598 : else if (IsA(node, PlaceHolderVar))
1281 : {
1282 818 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1283 :
1284 818 : if (phv->phlevelsup == context->sublevels_up &&
1285 1636 : (context->target_relids == NULL ||
1286 818 : bms_overlap(phv->phrels, context->target_relids)))
1287 : {
1288 818 : Relids newnullingrels = bms_union(phv->phnullingrels,
1289 : context->added_relids);
1290 :
1291 : /*
1292 : * We don't modify the contents of the PHV's expression, only add
1293 : * to phnullingrels. This corresponds to assuming that the PHV
1294 : * will be evaluated at the same level as before, then perhaps be
1295 : * nulled as it bubbles up. Hence, just flat-copy the node ...
1296 : */
1297 818 : phv = makeNode(PlaceHolderVar);
1298 818 : memcpy(phv, node, sizeof(PlaceHolderVar));
1299 : /* ... and replace the copy's phnullingrels field */
1300 818 : phv->phnullingrels = newnullingrels;
1301 818 : return (Node *) phv;
1302 : }
1303 : /* Otherwise fall through to copy the PlaceHolderVar normally */
1304 : }
1305 20780 : else if (IsA(node, Query))
1306 : {
1307 : /* Recurse into RTE or sublink subquery */
1308 : Query *newnode;
1309 :
1310 48 : context->sublevels_up++;
1311 48 : newnode = query_tree_mutator((Query *) node,
1312 : add_nulling_relids_mutator,
1313 : context,
1314 : 0);
1315 48 : context->sublevels_up--;
1316 48 : return (Node *) newnode;
1317 : }
1318 26854 : return expression_tree_mutator(node, add_nulling_relids_mutator, context);
1319 : }
1320 :
1321 : /*
1322 : * remove_nulling_relids() removes mentions of the specified RT index(es)
1323 : * in Var.varnullingrels and PlaceHolderVar.phnullingrels fields within
1324 : * the given expression, except in nodes belonging to rels listed in
1325 : * except_relids.
1326 : */
1327 : Node *
1328 409906 : remove_nulling_relids(Node *node,
1329 : const Bitmapset *removable_relids,
1330 : const Bitmapset *except_relids)
1331 : {
1332 : remove_nulling_relids_context context;
1333 :
1334 409906 : context.removable_relids = removable_relids;
1335 409906 : context.except_relids = except_relids;
1336 409906 : context.sublevels_up = 0;
1337 409906 : return query_or_expression_tree_mutator(node,
1338 : remove_nulling_relids_mutator,
1339 : &context,
1340 : 0);
1341 : }
1342 :
1343 : static Node *
1344 676020 : remove_nulling_relids_mutator(Node *node,
1345 : remove_nulling_relids_context *context)
1346 : {
1347 676020 : if (node == NULL)
1348 59584 : return NULL;
1349 616436 : if (IsA(node, Var))
1350 : {
1351 453086 : Var *var = (Var *) node;
1352 :
1353 453086 : if (var->varlevelsup == context->sublevels_up &&
1354 899622 : !bms_is_member(var->varno, context->except_relids) &&
1355 449764 : bms_overlap(var->varnullingrels, context->removable_relids))
1356 : {
1357 : /* Copy the Var ... */
1358 16044 : var = copyObject(var);
1359 : /* ... and replace the copy's varnullingrels field */
1360 16044 : var->varnullingrels = bms_difference(var->varnullingrels,
1361 : context->removable_relids);
1362 16044 : return (Node *) var;
1363 : }
1364 : /* Otherwise fall through to copy the Var normally */
1365 : }
1366 163350 : else if (IsA(node, PlaceHolderVar))
1367 : {
1368 4572 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1369 :
1370 4572 : if (phv->phlevelsup == context->sublevels_up &&
1371 4572 : !bms_overlap(phv->phrels, context->except_relids))
1372 : {
1373 : /*
1374 : * Note: it might seem desirable to remove the PHV altogether if
1375 : * phnullingrels goes to empty. Currently we dare not do that
1376 : * because we use PHVs in some cases to enforce separate identity
1377 : * of subexpressions; see wrap_option usages in prepjointree.c.
1378 : */
1379 : /* Copy the PlaceHolderVar and mutate what's below ... */
1380 : phv = (PlaceHolderVar *)
1381 4572 : expression_tree_mutator(node,
1382 : remove_nulling_relids_mutator,
1383 : context);
1384 : /* ... and replace the copy's phnullingrels field */
1385 4572 : phv->phnullingrels = bms_difference(phv->phnullingrels,
1386 : context->removable_relids);
1387 : /* We must also update phrels, if it contains a removable RTI */
1388 4572 : phv->phrels = bms_difference(phv->phrels,
1389 : context->removable_relids);
1390 : Assert(!bms_is_empty(phv->phrels));
1391 4572 : return (Node *) phv;
1392 : }
1393 : /* Otherwise fall through to copy the PlaceHolderVar normally */
1394 : }
1395 158778 : else if (IsA(node, Query))
1396 : {
1397 : /* Recurse into RTE or sublink subquery */
1398 : Query *newnode;
1399 :
1400 258 : context->sublevels_up++;
1401 258 : newnode = query_tree_mutator((Query *) node,
1402 : remove_nulling_relids_mutator,
1403 : context,
1404 : 0);
1405 258 : context->sublevels_up--;
1406 258 : return (Node *) newnode;
1407 : }
1408 595562 : return expression_tree_mutator(node, remove_nulling_relids_mutator, context);
1409 : }
1410 :
1411 :
1412 : /*
1413 : * replace_rte_variables() finds all Vars in an expression tree
1414 : * that reference a particular RTE, and replaces them with substitute
1415 : * expressions obtained from a caller-supplied callback function.
1416 : *
1417 : * When invoking replace_rte_variables on a portion of a Query, pass the
1418 : * address of the containing Query's hasSubLinks field as outer_hasSubLinks.
1419 : * Otherwise, pass NULL, but inserting a SubLink into a non-Query expression
1420 : * will then cause an error.
1421 : *
1422 : * Note: the business with inserted_sublink is needed to update hasSubLinks
1423 : * in subqueries when the replacement adds a subquery inside a subquery.
1424 : * Messy, isn't it? We do not need to do similar pushups for hasAggs,
1425 : * because it isn't possible for this transformation to insert a level-zero
1426 : * aggregate reference into a subquery --- it could only insert outer aggs.
1427 : * Likewise for hasWindowFuncs.
1428 : *
1429 : * Note: usually, we'd not expose the mutator function or context struct
1430 : * for a function like this. We do so because callbacks often find it
1431 : * convenient to recurse directly to the mutator on sub-expressions of
1432 : * what they will return.
1433 : */
1434 : Node *
1435 218304 : replace_rte_variables(Node *node, int target_varno, int sublevels_up,
1436 : replace_rte_variables_callback callback,
1437 : void *callback_arg,
1438 : bool *outer_hasSubLinks)
1439 : {
1440 : Node *result;
1441 : replace_rte_variables_context context;
1442 :
1443 218304 : context.callback = callback;
1444 218304 : context.callback_arg = callback_arg;
1445 218304 : context.target_varno = target_varno;
1446 218304 : context.sublevels_up = sublevels_up;
1447 :
1448 : /*
1449 : * We try to initialize inserted_sublink to true if there is no need to
1450 : * detect new sublinks because the query already has some.
1451 : */
1452 218304 : if (node && IsA(node, Query))
1453 5916 : context.inserted_sublink = ((Query *) node)->hasSubLinks;
1454 212388 : else if (outer_hasSubLinks)
1455 212104 : context.inserted_sublink = *outer_hasSubLinks;
1456 : else
1457 284 : context.inserted_sublink = false;
1458 :
1459 : /*
1460 : * Must be prepared to start with a Query or a bare expression tree; if
1461 : * it's a Query, we don't want to increment sublevels_up.
1462 : */
1463 218304 : result = query_or_expression_tree_mutator(node,
1464 : replace_rte_variables_mutator,
1465 : &context,
1466 : 0);
1467 :
1468 218298 : if (context.inserted_sublink)
1469 : {
1470 25060 : if (result && IsA(result, Query))
1471 198 : ((Query *) result)->hasSubLinks = true;
1472 24862 : else if (outer_hasSubLinks)
1473 24862 : *outer_hasSubLinks = true;
1474 : else
1475 0 : elog(ERROR, "replace_rte_variables inserted a SubLink, but has noplace to record it");
1476 : }
1477 :
1478 218298 : return result;
1479 : }
1480 :
1481 : Node *
1482 992258 : replace_rte_variables_mutator(Node *node,
1483 : replace_rte_variables_context *context)
1484 : {
1485 992258 : if (node == NULL)
1486 294374 : return NULL;
1487 697884 : if (IsA(node, Var))
1488 : {
1489 274902 : Var *var = (Var *) node;
1490 :
1491 274902 : if (var->varno == context->target_varno &&
1492 136022 : var->varlevelsup == context->sublevels_up)
1493 : {
1494 : /* Found a matching variable, make the substitution */
1495 : Node *newnode;
1496 :
1497 128186 : newnode = context->callback(var, context);
1498 : /* Detect if we are adding a sublink to query */
1499 128186 : if (!context->inserted_sublink)
1500 114578 : context->inserted_sublink = checkExprHasSubLink(newnode);
1501 128186 : return newnode;
1502 : }
1503 : /* otherwise fall through to copy the var normally */
1504 : }
1505 422982 : else if (IsA(node, CurrentOfExpr))
1506 : {
1507 6 : CurrentOfExpr *cexpr = (CurrentOfExpr *) node;
1508 :
1509 6 : if (cexpr->cvarno == context->target_varno &&
1510 6 : context->sublevels_up == 0)
1511 : {
1512 : /*
1513 : * We get here if a WHERE CURRENT OF expression turns out to apply
1514 : * to a view. Someday we might be able to translate the
1515 : * expression to apply to an underlying table of the view, but
1516 : * right now it's not implemented.
1517 : */
1518 6 : ereport(ERROR,
1519 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1520 : errmsg("WHERE CURRENT OF on a view is not implemented")));
1521 : }
1522 : /* otherwise fall through to copy the expr normally */
1523 : }
1524 422976 : else if (IsA(node, Query))
1525 : {
1526 : /* Recurse into RTE subquery or not-yet-planned sublink subquery */
1527 : Query *newnode;
1528 : bool save_inserted_sublink;
1529 :
1530 3380 : context->sublevels_up++;
1531 3380 : save_inserted_sublink = context->inserted_sublink;
1532 3380 : context->inserted_sublink = ((Query *) node)->hasSubLinks;
1533 3380 : newnode = query_tree_mutator((Query *) node,
1534 : replace_rte_variables_mutator,
1535 : context,
1536 : 0);
1537 3380 : newnode->hasSubLinks |= context->inserted_sublink;
1538 3380 : context->inserted_sublink = save_inserted_sublink;
1539 3380 : context->sublevels_up--;
1540 3380 : return (Node *) newnode;
1541 : }
1542 566312 : return expression_tree_mutator(node, replace_rte_variables_mutator, context);
1543 : }
1544 :
1545 :
1546 : /*
1547 : * map_variable_attnos() finds all user-column Vars in an expression tree
1548 : * that reference a particular RTE, and adjusts their varattnos according
1549 : * to the given mapping array (varattno n is replaced by attno_map[n-1]).
1550 : * Vars for system columns are not modified.
1551 : *
1552 : * A zero in the mapping array represents a dropped column, which should not
1553 : * appear in the expression.
1554 : *
1555 : * If the expression tree contains a whole-row Var for the target RTE,
1556 : * *found_whole_row is set to true. In addition, if to_rowtype is
1557 : * not InvalidOid, we replace the Var with a Var of that vartype, inserting
1558 : * a ConvertRowtypeExpr to map back to the rowtype expected by the expression.
1559 : * (Therefore, to_rowtype had better be a child rowtype of the rowtype of the
1560 : * RTE we're changing references to.) Callers that don't provide to_rowtype
1561 : * should report an error if *found_whole_row is true; we don't do that here
1562 : * because we don't know exactly what wording for the error message would
1563 : * be most appropriate. The caller will be aware of the context.
1564 : *
1565 : * This could be built using replace_rte_variables and a callback function,
1566 : * but since we don't ever need to insert sublinks, replace_rte_variables is
1567 : * overly complicated.
1568 : */
1569 :
1570 : typedef struct
1571 : {
1572 : int target_varno; /* RTE index to search for */
1573 : int sublevels_up; /* (current) nesting depth */
1574 : const AttrMap *attno_map; /* map array for user attnos */
1575 : Oid to_rowtype; /* change whole-row Vars to this type */
1576 : bool *found_whole_row; /* output flag */
1577 : } map_variable_attnos_context;
1578 :
1579 : static Node *
1580 111336 : map_variable_attnos_mutator(Node *node,
1581 : map_variable_attnos_context *context)
1582 : {
1583 111336 : if (node == NULL)
1584 172 : return NULL;
1585 111164 : if (IsA(node, Var))
1586 : {
1587 26228 : Var *var = (Var *) node;
1588 :
1589 26228 : if (var->varno == context->target_varno &&
1590 26012 : var->varlevelsup == context->sublevels_up)
1591 : {
1592 : /* Found a matching variable, make the substitution */
1593 26012 : Var *newvar = (Var *) palloc(sizeof(Var));
1594 26012 : int attno = var->varattno;
1595 :
1596 26012 : *newvar = *var; /* initially copy all fields of the Var */
1597 :
1598 26012 : if (attno > 0)
1599 : {
1600 : /* user-defined column, replace attno */
1601 25688 : if (attno > context->attno_map->maplen ||
1602 25688 : context->attno_map->attnums[attno - 1] == 0)
1603 0 : elog(ERROR, "unexpected varattno %d in expression to be mapped",
1604 : attno);
1605 25688 : newvar->varattno = context->attno_map->attnums[attno - 1];
1606 : /* If the syntactic referent is same RTE, fix it too */
1607 25688 : if (newvar->varnosyn == context->target_varno)
1608 25610 : newvar->varattnosyn = newvar->varattno;
1609 : }
1610 324 : else if (attno == 0)
1611 : {
1612 : /* whole-row variable, warn caller */
1613 54 : *(context->found_whole_row) = true;
1614 :
1615 : /* If the caller expects us to convert the Var, do so. */
1616 54 : if (OidIsValid(context->to_rowtype) &&
1617 48 : context->to_rowtype != var->vartype)
1618 : {
1619 : ConvertRowtypeExpr *r;
1620 :
1621 : /* This certainly won't work for a RECORD variable. */
1622 : Assert(var->vartype != RECORDOID);
1623 :
1624 : /* Var itself is changed to the requested type. */
1625 48 : newvar->vartype = context->to_rowtype;
1626 :
1627 : /*
1628 : * Add a conversion node on top to convert back to the
1629 : * original type expected by the expression.
1630 : */
1631 48 : r = makeNode(ConvertRowtypeExpr);
1632 48 : r->arg = (Expr *) newvar;
1633 48 : r->resulttype = var->vartype;
1634 48 : r->convertformat = COERCE_IMPLICIT_CAST;
1635 48 : r->location = -1;
1636 :
1637 48 : return (Node *) r;
1638 : }
1639 : }
1640 25964 : return (Node *) newvar;
1641 : }
1642 : /* otherwise fall through to copy the var normally */
1643 : }
1644 84936 : else if (IsA(node, ConvertRowtypeExpr))
1645 : {
1646 48 : ConvertRowtypeExpr *r = (ConvertRowtypeExpr *) node;
1647 48 : Var *var = (Var *) r->arg;
1648 :
1649 : /*
1650 : * If this is coercing a whole-row Var that we need to convert, then
1651 : * just convert the Var without adding an extra ConvertRowtypeExpr.
1652 : * Effectively we're simplifying var::parenttype::grandparenttype into
1653 : * just var::grandparenttype. This avoids building stacks of CREs if
1654 : * this function is applied repeatedly.
1655 : */
1656 48 : if (IsA(var, Var) &&
1657 36 : var->varno == context->target_varno &&
1658 30 : var->varlevelsup == context->sublevels_up &&
1659 30 : var->varattno == 0 &&
1660 30 : OidIsValid(context->to_rowtype) &&
1661 30 : context->to_rowtype != var->vartype)
1662 : {
1663 : ConvertRowtypeExpr *newnode;
1664 30 : Var *newvar = (Var *) palloc(sizeof(Var));
1665 :
1666 : /* whole-row variable, warn caller */
1667 30 : *(context->found_whole_row) = true;
1668 :
1669 30 : *newvar = *var; /* initially copy all fields of the Var */
1670 :
1671 : /* This certainly won't work for a RECORD variable. */
1672 : Assert(var->vartype != RECORDOID);
1673 :
1674 : /* Var itself is changed to the requested type. */
1675 30 : newvar->vartype = context->to_rowtype;
1676 :
1677 30 : newnode = (ConvertRowtypeExpr *) palloc(sizeof(ConvertRowtypeExpr));
1678 30 : *newnode = *r; /* initially copy all fields of the CRE */
1679 30 : newnode->arg = (Expr *) newvar;
1680 :
1681 30 : return (Node *) newnode;
1682 : }
1683 : /* otherwise fall through to process the expression normally */
1684 : }
1685 84888 : else if (IsA(node, Query))
1686 : {
1687 : /* Recurse into RTE subquery or not-yet-planned sublink subquery */
1688 : Query *newnode;
1689 :
1690 0 : context->sublevels_up++;
1691 0 : newnode = query_tree_mutator((Query *) node,
1692 : map_variable_attnos_mutator,
1693 : context,
1694 : 0);
1695 0 : context->sublevels_up--;
1696 0 : return (Node *) newnode;
1697 : }
1698 85122 : return expression_tree_mutator(node, map_variable_attnos_mutator, context);
1699 : }
1700 :
1701 : Node *
1702 9284 : map_variable_attnos(Node *node,
1703 : int target_varno, int sublevels_up,
1704 : const AttrMap *attno_map,
1705 : Oid to_rowtype, bool *found_whole_row)
1706 : {
1707 : map_variable_attnos_context context;
1708 :
1709 9284 : context.target_varno = target_varno;
1710 9284 : context.sublevels_up = sublevels_up;
1711 9284 : context.attno_map = attno_map;
1712 9284 : context.to_rowtype = to_rowtype;
1713 9284 : context.found_whole_row = found_whole_row;
1714 :
1715 9284 : *found_whole_row = false;
1716 :
1717 : /*
1718 : * Must be prepared to start with a Query or a bare expression tree; if
1719 : * it's a Query, we don't want to increment sublevels_up.
1720 : */
1721 9284 : return query_or_expression_tree_mutator(node,
1722 : map_variable_attnos_mutator,
1723 : &context,
1724 : 0);
1725 : }
1726 :
1727 :
1728 : /*
1729 : * ReplaceVarsFromTargetList - replace Vars with items from a targetlist
1730 : *
1731 : * Vars matching target_varno and sublevels_up are replaced by the
1732 : * entry with matching resno from targetlist, if there is one.
1733 : *
1734 : * If there is no matching resno for such a Var, the action depends on the
1735 : * nomatch_option:
1736 : * REPLACEVARS_REPORT_ERROR: throw an error
1737 : * REPLACEVARS_CHANGE_VARNO: change Var's varno to nomatch_varno
1738 : * REPLACEVARS_SUBSTITUTE_NULL: replace Var with a NULL Const of same type
1739 : *
1740 : * The caller must also provide target_rte, the RTE describing the target
1741 : * relation. This is needed to handle whole-row Vars referencing the target.
1742 : * We expand such Vars into RowExpr constructs.
1743 : *
1744 : * In addition, for INSERT/UPDATE/DELETE/MERGE queries, the caller must
1745 : * provide result_relation, the index of the result relation in the rewritten
1746 : * query. This is needed to handle OLD/NEW RETURNING list Vars referencing
1747 : * target_varno. When such Vars are expanded, their varreturningtype is
1748 : * copied onto any replacement Vars referencing result_relation. In addition,
1749 : * if the replacement expression from the targetlist is not simply a Var
1750 : * referencing result_relation, it is wrapped in a ReturningExpr node (causing
1751 : * the executor to return NULL if the OLD/NEW row doesn't exist).
1752 : *
1753 : * Note that ReplaceVarFromTargetList always generates the replacement
1754 : * expression with varlevelsup = 0. The caller is responsible for adjusting
1755 : * the varlevelsup if needed. This simplifies the caller's life if it wants to
1756 : * cache the replacement expressions.
1757 : *
1758 : * outer_hasSubLinks works the same as for replace_rte_variables().
1759 : */
1760 :
1761 : typedef struct
1762 : {
1763 : RangeTblEntry *target_rte;
1764 : List *targetlist;
1765 : int result_relation;
1766 : ReplaceVarsNoMatchOption nomatch_option;
1767 : int nomatch_varno;
1768 : } ReplaceVarsFromTargetList_context;
1769 :
1770 : static Node *
1771 11272 : ReplaceVarsFromTargetList_callback(Var *var,
1772 : replace_rte_variables_context *context)
1773 : {
1774 11272 : ReplaceVarsFromTargetList_context *rcon = (ReplaceVarsFromTargetList_context *) context->callback_arg;
1775 : Node *newnode;
1776 :
1777 11272 : newnode = ReplaceVarFromTargetList(var,
1778 : rcon->target_rte,
1779 : rcon->targetlist,
1780 : rcon->result_relation,
1781 : rcon->nomatch_option,
1782 : rcon->nomatch_varno);
1783 :
1784 : /* Must adjust varlevelsup if replaced Var is within a subquery */
1785 11272 : if (var->varlevelsup > 0)
1786 258 : IncrementVarSublevelsUp(newnode, var->varlevelsup, 0);
1787 :
1788 11272 : return newnode;
1789 : }
1790 :
1791 : Node *
1792 127306 : ReplaceVarFromTargetList(Var *var,
1793 : RangeTblEntry *target_rte,
1794 : List *targetlist,
1795 : int result_relation,
1796 : ReplaceVarsNoMatchOption nomatch_option,
1797 : int nomatch_varno)
1798 : {
1799 : TargetEntry *tle;
1800 :
1801 127306 : if (var->varattno == InvalidAttrNumber)
1802 : {
1803 : /* Must expand whole-tuple reference into RowExpr */
1804 : RowExpr *rowexpr;
1805 : List *colnames;
1806 : List *fields;
1807 : ListCell *lc;
1808 :
1809 : /*
1810 : * If generating an expansion for a var of a named rowtype (ie, this
1811 : * is a plain relation RTE), then we must include dummy items for
1812 : * dropped columns. If the var is RECORD (ie, this is a JOIN), then
1813 : * omit dropped columns. In the latter case, attach column names to
1814 : * the RowExpr for use of the executor and ruleutils.c.
1815 : *
1816 : * In order to be able to cache the results, we always generate the
1817 : * expansion with varlevelsup = 0. The caller is responsible for
1818 : * adjusting it if needed.
1819 : *
1820 : * The varreturningtype is copied onto each individual field Var, so
1821 : * that it is handled correctly when we recurse.
1822 : */
1823 736 : expandRTE(target_rte,
1824 : var->varno, 0 /* not varlevelsup */ ,
1825 : var->varreturningtype, var->location,
1826 736 : (var->vartype != RECORDOID),
1827 : &colnames, &fields);
1828 736 : rowexpr = makeNode(RowExpr);
1829 : /* the fields will be set below */
1830 736 : rowexpr->args = NIL;
1831 736 : rowexpr->row_typeid = var->vartype;
1832 736 : rowexpr->row_format = COERCE_IMPLICIT_CAST;
1833 736 : rowexpr->colnames = (var->vartype == RECORDOID) ? colnames : NIL;
1834 736 : rowexpr->location = var->location;
1835 : /* Adjust the generated per-field Vars... */
1836 2726 : foreach(lc, fields)
1837 : {
1838 1990 : Node *field = lfirst(lc);
1839 :
1840 1990 : if (field && IsA(field, Var))
1841 1990 : field = ReplaceVarFromTargetList((Var *) field,
1842 : target_rte,
1843 : targetlist,
1844 : result_relation,
1845 : nomatch_option,
1846 : nomatch_varno);
1847 1990 : rowexpr->args = lappend(rowexpr->args, field);
1848 : }
1849 :
1850 : /* Wrap it in a ReturningExpr, if needed, per comments above */
1851 736 : if (var->varreturningtype != VAR_RETURNING_DEFAULT)
1852 : {
1853 78 : ReturningExpr *rexpr = makeNode(ReturningExpr);
1854 :
1855 78 : rexpr->retlevelsup = 0;
1856 78 : rexpr->retold = (var->varreturningtype == VAR_RETURNING_OLD);
1857 78 : rexpr->retexpr = (Expr *) rowexpr;
1858 :
1859 78 : return (Node *) rexpr;
1860 : }
1861 :
1862 658 : return (Node *) rowexpr;
1863 : }
1864 :
1865 : /* Normal case referencing one targetlist element */
1866 126570 : tle = get_tle_by_resno(targetlist, var->varattno);
1867 :
1868 126570 : if (tle == NULL || tle->resjunk)
1869 : {
1870 : /* Failed to find column in targetlist */
1871 504 : switch (nomatch_option)
1872 : {
1873 0 : case REPLACEVARS_REPORT_ERROR:
1874 : /* fall through, throw error below */
1875 0 : break;
1876 :
1877 354 : case REPLACEVARS_CHANGE_VARNO:
1878 354 : var = copyObject(var);
1879 354 : var->varno = nomatch_varno;
1880 354 : var->varlevelsup = 0;
1881 : /* we leave the syntactic referent alone */
1882 354 : return (Node *) var;
1883 :
1884 150 : case REPLACEVARS_SUBSTITUTE_NULL:
1885 : {
1886 : /*
1887 : * If Var is of domain type, we must add a CoerceToDomain
1888 : * node, in case there is a NOT NULL domain constraint.
1889 : */
1890 : int16 vartyplen;
1891 : bool vartypbyval;
1892 :
1893 150 : get_typlenbyval(var->vartype, &vartyplen, &vartypbyval);
1894 150 : return coerce_null_to_domain(var->vartype,
1895 : var->vartypmod,
1896 : var->varcollid,
1897 : vartyplen,
1898 : vartypbyval);
1899 : }
1900 : }
1901 0 : elog(ERROR, "could not find replacement targetlist entry for attno %d",
1902 : var->varattno);
1903 : return NULL; /* keep compiler quiet */
1904 : }
1905 : else
1906 : {
1907 : /* Make a copy of the tlist item to return */
1908 126066 : Expr *newnode = copyObject(tle->expr);
1909 :
1910 : /*
1911 : * Check to see if the tlist item contains a PARAM_MULTIEXPR Param,
1912 : * and throw error if so. This case could only happen when expanding
1913 : * an ON UPDATE rule's NEW variable and the referenced tlist item in
1914 : * the original UPDATE command is part of a multiple assignment. There
1915 : * seems no practical way to handle such cases without multiple
1916 : * evaluation of the multiple assignment's sub-select, which would
1917 : * create semantic oddities that users of rules would probably prefer
1918 : * not to cope with. So treat it as an unimplemented feature.
1919 : */
1920 126066 : if (contains_multiexpr_param((Node *) newnode, NULL))
1921 0 : ereport(ERROR,
1922 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1923 : errmsg("NEW variables in ON UPDATE rules cannot reference columns that are part of a multiple assignment in the subject UPDATE command")));
1924 :
1925 : /* Handle any OLD/NEW RETURNING list Vars */
1926 126066 : if (var->varreturningtype != VAR_RETURNING_DEFAULT)
1927 : {
1928 : /*
1929 : * Copy varreturningtype onto any Vars in the tlist item that
1930 : * refer to result_relation (which had better be non-zero).
1931 : */
1932 1170 : if (result_relation == 0)
1933 0 : elog(ERROR, "variable returning old/new found outside RETURNING list");
1934 :
1935 1170 : SetVarReturningType((Node *) newnode, result_relation,
1936 : 0, var->varreturningtype);
1937 :
1938 : /* Wrap it in a ReturningExpr, if needed, per comments above */
1939 1170 : if (!IsA(newnode, Var) ||
1940 894 : ((Var *) newnode)->varno != result_relation ||
1941 834 : ((Var *) newnode)->varlevelsup != 0)
1942 : {
1943 336 : ReturningExpr *rexpr = makeNode(ReturningExpr);
1944 :
1945 336 : rexpr->retlevelsup = 0;
1946 336 : rexpr->retold = (var->varreturningtype == VAR_RETURNING_OLD);
1947 336 : rexpr->retexpr = newnode;
1948 :
1949 336 : newnode = (Expr *) rexpr;
1950 : }
1951 : }
1952 :
1953 126066 : return (Node *) newnode;
1954 : }
1955 : }
1956 :
1957 : Node *
1958 7592 : ReplaceVarsFromTargetList(Node *node,
1959 : int target_varno, int sublevels_up,
1960 : RangeTblEntry *target_rte,
1961 : List *targetlist,
1962 : int result_relation,
1963 : ReplaceVarsNoMatchOption nomatch_option,
1964 : int nomatch_varno,
1965 : bool *outer_hasSubLinks)
1966 : {
1967 : ReplaceVarsFromTargetList_context context;
1968 :
1969 7592 : context.target_rte = target_rte;
1970 7592 : context.targetlist = targetlist;
1971 7592 : context.result_relation = result_relation;
1972 7592 : context.nomatch_option = nomatch_option;
1973 7592 : context.nomatch_varno = nomatch_varno;
1974 :
1975 7592 : return replace_rte_variables(node, target_varno, sublevels_up,
1976 : ReplaceVarsFromTargetList_callback,
1977 : &context,
1978 : outer_hasSubLinks);
1979 : }
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