Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * appendinfo.c
4 : * Routines for mapping between append parent(s) and children
5 : *
6 : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
7 : * Portions Copyright (c) 1994, Regents of the University of California
8 : *
9 : *
10 : * IDENTIFICATION
11 : * src/backend/optimizer/util/appendinfo.c
12 : *
13 : *-------------------------------------------------------------------------
14 : */
15 : #include "postgres.h"
16 :
17 : #include "access/htup_details.h"
18 : #include "access/table.h"
19 : #include "foreign/fdwapi.h"
20 : #include "nodes/makefuncs.h"
21 : #include "nodes/nodeFuncs.h"
22 : #include "optimizer/appendinfo.h"
23 : #include "optimizer/pathnode.h"
24 : #include "optimizer/planmain.h"
25 : #include "parser/parsetree.h"
26 : #include "utils/lsyscache.h"
27 : #include "utils/rel.h"
28 : #include "utils/syscache.h"
29 :
30 :
31 : typedef struct
32 : {
33 : PlannerInfo *root;
34 : int nappinfos;
35 : AppendRelInfo **appinfos;
36 : } adjust_appendrel_attrs_context;
37 :
38 : static void make_inh_translation_list(Relation oldrelation,
39 : Relation newrelation,
40 : Index newvarno,
41 : AppendRelInfo *appinfo);
42 : static Node *adjust_appendrel_attrs_mutator(Node *node,
43 : adjust_appendrel_attrs_context *context);
44 :
45 :
46 : /*
47 : * make_append_rel_info
48 : * Build an AppendRelInfo for the parent-child pair
49 : */
50 : AppendRelInfo *
51 42246 : make_append_rel_info(Relation parentrel, Relation childrel,
52 : Index parentRTindex, Index childRTindex)
53 : {
54 42246 : AppendRelInfo *appinfo = makeNode(AppendRelInfo);
55 :
56 42246 : appinfo->parent_relid = parentRTindex;
57 42246 : appinfo->child_relid = childRTindex;
58 42246 : appinfo->parent_reltype = parentrel->rd_rel->reltype;
59 42246 : appinfo->child_reltype = childrel->rd_rel->reltype;
60 42246 : make_inh_translation_list(parentrel, childrel, childRTindex, appinfo);
61 42244 : appinfo->parent_reloid = RelationGetRelid(parentrel);
62 :
63 42244 : return appinfo;
64 : }
65 :
66 : /*
67 : * make_inh_translation_list
68 : * Build the list of translations from parent Vars to child Vars for
69 : * an inheritance child, as well as a reverse-translation array.
70 : *
71 : * The reverse-translation array has an entry for each child relation
72 : * column, which is either the 1-based index of the corresponding parent
73 : * column, or 0 if there's no match (that happens for dropped child columns,
74 : * as well as child columns beyond those of the parent, which are allowed in
75 : * traditional inheritance though not partitioning).
76 : *
77 : * For paranoia's sake, we match type/collation as well as attribute name.
78 : */
79 : static void
80 42246 : make_inh_translation_list(Relation oldrelation, Relation newrelation,
81 : Index newvarno,
82 : AppendRelInfo *appinfo)
83 : {
84 42246 : List *vars = NIL;
85 : AttrNumber *pcolnos;
86 42246 : TupleDesc old_tupdesc = RelationGetDescr(oldrelation);
87 42246 : TupleDesc new_tupdesc = RelationGetDescr(newrelation);
88 42246 : Oid new_relid = RelationGetRelid(newrelation);
89 42246 : int oldnatts = old_tupdesc->natts;
90 42246 : int newnatts = new_tupdesc->natts;
91 : int old_attno;
92 42246 : int new_attno = 0;
93 :
94 : /* Initialize reverse-translation array with all entries zero */
95 42246 : appinfo->num_child_cols = newnatts;
96 42246 : appinfo->parent_colnos = pcolnos =
97 42246 : (AttrNumber *) palloc0(newnatts * sizeof(AttrNumber));
98 :
99 156010 : for (old_attno = 0; old_attno < oldnatts; old_attno++)
100 : {
101 : Form_pg_attribute att;
102 : char *attname;
103 : Oid atttypid;
104 : int32 atttypmod;
105 : Oid attcollation;
106 :
107 113766 : att = TupleDescAttr(old_tupdesc, old_attno);
108 113766 : if (att->attisdropped)
109 : {
110 : /* Just put NULL into this list entry */
111 3132 : vars = lappend(vars, NULL);
112 3132 : continue;
113 : }
114 110634 : attname = NameStr(att->attname);
115 110634 : atttypid = att->atttypid;
116 110634 : atttypmod = att->atttypmod;
117 110634 : attcollation = att->attcollation;
118 :
119 : /*
120 : * When we are generating the "translation list" for the parent table
121 : * of an inheritance set, no need to search for matches.
122 : */
123 110634 : if (oldrelation == newrelation)
124 : {
125 6860 : vars = lappend(vars, makeVar(newvarno,
126 6860 : (AttrNumber) (old_attno + 1),
127 : atttypid,
128 : atttypmod,
129 : attcollation,
130 : 0));
131 6860 : pcolnos[old_attno] = old_attno + 1;
132 6860 : continue;
133 : }
134 :
135 : /*
136 : * Otherwise we have to search for the matching column by name.
137 : * There's no guarantee it'll have the same column position, because
138 : * of cases like ALTER TABLE ADD COLUMN and multiple inheritance.
139 : * However, in simple cases, the relative order of columns is mostly
140 : * the same in both relations, so try the column of newrelation that
141 : * follows immediately after the one that we just found, and if that
142 : * fails, let syscache handle it.
143 : */
144 103774 : if (new_attno >= newnatts ||
145 101516 : (att = TupleDescAttr(new_tupdesc, new_attno))->attisdropped ||
146 100576 : strcmp(attname, NameStr(att->attname)) != 0)
147 : {
148 : HeapTuple newtup;
149 :
150 8386 : newtup = SearchSysCacheAttName(new_relid, attname);
151 8386 : if (!HeapTupleIsValid(newtup))
152 0 : elog(ERROR, "could not find inherited attribute \"%s\" of relation \"%s\"",
153 : attname, RelationGetRelationName(newrelation));
154 8386 : new_attno = ((Form_pg_attribute) GETSTRUCT(newtup))->attnum - 1;
155 : Assert(new_attno >= 0 && new_attno < newnatts);
156 8386 : ReleaseSysCache(newtup);
157 :
158 8386 : att = TupleDescAttr(new_tupdesc, new_attno);
159 : }
160 :
161 : /* Found it, check type and collation match */
162 103774 : if (atttypid != att->atttypid || atttypmod != att->atttypmod)
163 2 : ereport(ERROR,
164 : (errcode(ERRCODE_INVALID_COLUMN_DEFINITION),
165 : errmsg("attribute \"%s\" of relation \"%s\" does not match parent's type",
166 : attname, RelationGetRelationName(newrelation))));
167 103772 : if (attcollation != att->attcollation)
168 0 : ereport(ERROR,
169 : (errcode(ERRCODE_INVALID_COLUMN_DEFINITION),
170 : errmsg("attribute \"%s\" of relation \"%s\" does not match parent's collation",
171 : attname, RelationGetRelationName(newrelation))));
172 :
173 103772 : vars = lappend(vars, makeVar(newvarno,
174 103772 : (AttrNumber) (new_attno + 1),
175 : atttypid,
176 : atttypmod,
177 : attcollation,
178 : 0));
179 103772 : pcolnos[new_attno] = old_attno + 1;
180 103772 : new_attno++;
181 : }
182 :
183 42244 : appinfo->translated_vars = vars;
184 42244 : }
185 :
186 : /*
187 : * adjust_appendrel_attrs
188 : * Copy the specified query or expression and translate Vars referring to a
189 : * parent rel to refer to the corresponding child rel instead. We also
190 : * update rtindexes appearing outside Vars, such as resultRelation and
191 : * jointree relids.
192 : *
193 : * Note: this is only applied after conversion of sublinks to subplans,
194 : * so we don't need to cope with recursion into sub-queries.
195 : *
196 : * Note: this is not hugely different from what pullup_replace_vars() does;
197 : * maybe we should try to fold the two routines together.
198 : */
199 : Node *
200 292792 : adjust_appendrel_attrs(PlannerInfo *root, Node *node, int nappinfos,
201 : AppendRelInfo **appinfos)
202 : {
203 : adjust_appendrel_attrs_context context;
204 :
205 292792 : context.root = root;
206 292792 : context.nappinfos = nappinfos;
207 292792 : context.appinfos = appinfos;
208 :
209 : /* If there's nothing to adjust, don't call this function. */
210 : Assert(nappinfos >= 1 && appinfos != NULL);
211 :
212 : /* Should never be translating a Query tree. */
213 : Assert(node == NULL || !IsA(node, Query));
214 :
215 292792 : return adjust_appendrel_attrs_mutator(node, &context);
216 : }
217 :
218 : static Node *
219 1516318 : adjust_appendrel_attrs_mutator(Node *node,
220 : adjust_appendrel_attrs_context *context)
221 : {
222 1516318 : AppendRelInfo **appinfos = context->appinfos;
223 1516318 : int nappinfos = context->nappinfos;
224 : int cnt;
225 :
226 1516318 : if (node == NULL)
227 283450 : return NULL;
228 1232868 : if (IsA(node, Var))
229 : {
230 551896 : Var *var = (Var *) copyObject(node);
231 551896 : AppendRelInfo *appinfo = NULL;
232 :
233 551896 : if (var->varlevelsup != 0)
234 0 : return (Node *) var; /* no changes needed */
235 :
236 : /*
237 : * You might think we need to adjust var->varnullingrels, but that
238 : * shouldn't need any changes. It will contain outer-join relids,
239 : * while the transformation we are making affects only baserels.
240 : * Below, we just propagate var->varnullingrels into the translated
241 : * Var.
242 : *
243 : * If var->varnullingrels isn't empty, and the translation wouldn't be
244 : * a Var, we have to fail. One could imagine wrapping the translated
245 : * expression in a PlaceHolderVar, but that won't work because this is
246 : * typically used after freezing placeholders. Fortunately, the case
247 : * appears unreachable at the moment. We can see nonempty
248 : * var->varnullingrels here, but only in cases involving partitionwise
249 : * joining, and in such cases the translations will always be Vars.
250 : * (Non-Var translations occur only for appendrels made by flattening
251 : * UNION ALL subqueries.) Should we need to make this work in future,
252 : * a possible fix is to mandate that prepjointree.c create PHVs for
253 : * all non-Var outputs of such subqueries, and then we could look up
254 : * the pre-existing PHV here. Or perhaps just wrap the translations
255 : * that way to begin with?
256 : *
257 : * If var->varreturningtype is not VAR_RETURNING_DEFAULT, then that
258 : * also needs to be copied to the translated Var. That too would fail
259 : * if the translation wasn't a Var, but that should never happen since
260 : * a non-default var->varreturningtype is only used for Vars referring
261 : * to the result relation, which should never be a flattened UNION ALL
262 : * subquery.
263 : */
264 :
265 690560 : for (cnt = 0; cnt < nappinfos; cnt++)
266 : {
267 649602 : if (var->varno == appinfos[cnt]->parent_relid)
268 : {
269 510938 : appinfo = appinfos[cnt];
270 510938 : break;
271 : }
272 : }
273 :
274 551896 : if (appinfo)
275 : {
276 510938 : var->varno = appinfo->child_relid;
277 : /* it's now a generated Var, so drop any syntactic labeling */
278 510938 : var->varnosyn = 0;
279 510938 : var->varattnosyn = 0;
280 510938 : if (var->varattno > 0)
281 : {
282 : Node *newnode;
283 :
284 492956 : if (var->varattno > list_length(appinfo->translated_vars))
285 0 : elog(ERROR, "attribute %d of relation \"%s\" does not exist",
286 : var->varattno, get_rel_name(appinfo->parent_reloid));
287 492956 : newnode = copyObject(list_nth(appinfo->translated_vars,
288 : var->varattno - 1));
289 492956 : if (newnode == NULL)
290 0 : elog(ERROR, "attribute %d of relation \"%s\" does not exist",
291 : var->varattno, get_rel_name(appinfo->parent_reloid));
292 492956 : if (IsA(newnode, Var))
293 : {
294 484108 : ((Var *) newnode)->varreturningtype = var->varreturningtype;
295 484108 : ((Var *) newnode)->varnullingrels = var->varnullingrels;
296 : }
297 : else
298 : {
299 8848 : if (var->varreturningtype != VAR_RETURNING_DEFAULT)
300 0 : elog(ERROR, "failed to apply returningtype to a non-Var");
301 8848 : if (var->varnullingrels != NULL)
302 0 : elog(ERROR, "failed to apply nullingrels to a non-Var");
303 : }
304 492956 : return newnode;
305 : }
306 17982 : else if (var->varattno == 0)
307 : {
308 : /*
309 : * Whole-row Var: if we are dealing with named rowtypes, we
310 : * can use a whole-row Var for the child table plus a coercion
311 : * step to convert the tuple layout to the parent's rowtype.
312 : * Otherwise we have to generate a RowExpr.
313 : */
314 1090 : if (OidIsValid(appinfo->child_reltype))
315 : {
316 : Assert(var->vartype == appinfo->parent_reltype);
317 1034 : if (appinfo->parent_reltype != appinfo->child_reltype)
318 : {
319 842 : ConvertRowtypeExpr *r = makeNode(ConvertRowtypeExpr);
320 :
321 842 : r->arg = (Expr *) var;
322 842 : r->resulttype = appinfo->parent_reltype;
323 842 : r->convertformat = COERCE_IMPLICIT_CAST;
324 842 : r->location = -1;
325 : /* Make sure the Var node has the right type ID, too */
326 842 : var->vartype = appinfo->child_reltype;
327 842 : return (Node *) r;
328 : }
329 : }
330 : else
331 : {
332 : /*
333 : * Build a RowExpr containing the translated variables.
334 : *
335 : * In practice var->vartype will always be RECORDOID here,
336 : * so we need to come up with some suitable column names.
337 : * We use the parent RTE's column names.
338 : *
339 : * Note: we can't get here for inheritance cases, so there
340 : * is no need to worry that translated_vars might contain
341 : * some dummy NULLs.
342 : */
343 : RowExpr *rowexpr;
344 : List *fields;
345 : RangeTblEntry *rte;
346 :
347 56 : rte = rt_fetch(appinfo->parent_relid,
348 : context->root->parse->rtable);
349 56 : fields = copyObject(appinfo->translated_vars);
350 56 : rowexpr = makeNode(RowExpr);
351 56 : rowexpr->args = fields;
352 56 : rowexpr->row_typeid = var->vartype;
353 56 : rowexpr->row_format = COERCE_IMPLICIT_CAST;
354 56 : rowexpr->colnames = copyObject(rte->eref->colnames);
355 56 : rowexpr->location = -1;
356 :
357 56 : if (var->varreturningtype != VAR_RETURNING_DEFAULT)
358 0 : elog(ERROR, "failed to apply returningtype to a non-Var");
359 56 : if (var->varnullingrels != NULL)
360 0 : elog(ERROR, "failed to apply nullingrels to a non-Var");
361 :
362 56 : return (Node *) rowexpr;
363 : }
364 : }
365 : /* system attributes don't need any other translation */
366 : }
367 40958 : else if (var->varno == ROWID_VAR)
368 : {
369 : /*
370 : * If it's a ROWID_VAR placeholder, see if we've reached a leaf
371 : * target rel, for which we can translate the Var to a specific
372 : * instantiation. We should never be asked to translate to a set
373 : * of relids containing more than one leaf target rel, so the
374 : * answer will be unique. If we're still considering non-leaf
375 : * inheritance levels, return the ROWID_VAR Var as-is.
376 : */
377 19302 : Relids leaf_result_relids = context->root->leaf_result_relids;
378 19302 : Index leaf_relid = 0;
379 :
380 38604 : for (cnt = 0; cnt < nappinfos; cnt++)
381 : {
382 19302 : if (bms_is_member(appinfos[cnt]->child_relid,
383 : leaf_result_relids))
384 : {
385 17122 : if (leaf_relid)
386 0 : elog(ERROR, "cannot translate to multiple leaf relids");
387 17122 : leaf_relid = appinfos[cnt]->child_relid;
388 : }
389 : }
390 :
391 19302 : if (leaf_relid)
392 : {
393 : RowIdentityVarInfo *ridinfo = (RowIdentityVarInfo *)
394 17122 : list_nth(context->root->row_identity_vars, var->varattno - 1);
395 :
396 17122 : if (bms_is_member(leaf_relid, ridinfo->rowidrels))
397 : {
398 : /* Substitute the Var given in the RowIdentityVarInfo */
399 17030 : var = copyObject(ridinfo->rowidvar);
400 : /* ... but use the correct relid */
401 17030 : var->varno = leaf_relid;
402 : /* identity vars shouldn't have nulling rels */
403 : Assert(var->varnullingrels == NULL);
404 : /* varnosyn in the RowIdentityVarInfo is probably wrong */
405 17030 : var->varnosyn = 0;
406 17030 : var->varattnosyn = 0;
407 : }
408 : else
409 : {
410 : /*
411 : * This leaf rel can't return the desired value, so
412 : * substitute a NULL of the correct type.
413 : */
414 92 : return (Node *) makeNullConst(var->vartype,
415 : var->vartypmod,
416 : var->varcollid);
417 : }
418 : }
419 : }
420 57950 : return (Node *) var;
421 : }
422 680972 : if (IsA(node, CurrentOfExpr))
423 : {
424 184 : CurrentOfExpr *cexpr = (CurrentOfExpr *) copyObject(node);
425 :
426 184 : for (cnt = 0; cnt < nappinfos; cnt++)
427 : {
428 184 : AppendRelInfo *appinfo = appinfos[cnt];
429 :
430 184 : if (cexpr->cvarno == appinfo->parent_relid)
431 : {
432 184 : cexpr->cvarno = appinfo->child_relid;
433 184 : break;
434 : }
435 : }
436 184 : return (Node *) cexpr;
437 : }
438 680788 : if (IsA(node, PlaceHolderVar))
439 : {
440 : /* Copy the PlaceHolderVar node with correct mutation of subnodes */
441 : PlaceHolderVar *phv;
442 :
443 2808 : phv = (PlaceHolderVar *) expression_tree_mutator(node,
444 : adjust_appendrel_attrs_mutator,
445 : context);
446 : /* now fix PlaceHolderVar's relid sets */
447 2808 : if (phv->phlevelsup == 0)
448 : {
449 2808 : phv->phrels = adjust_child_relids(phv->phrels,
450 : nappinfos, appinfos);
451 : /* as above, we needn't touch phnullingrels */
452 : }
453 2808 : return (Node *) phv;
454 : }
455 : /* Shouldn't need to handle planner auxiliary nodes here */
456 : Assert(!IsA(node, SpecialJoinInfo));
457 : Assert(!IsA(node, AppendRelInfo));
458 : Assert(!IsA(node, PlaceHolderInfo));
459 : Assert(!IsA(node, MinMaxAggInfo));
460 :
461 : /*
462 : * We have to process RestrictInfo nodes specially. (Note: although
463 : * set_append_rel_pathlist will hide RestrictInfos in the parent's
464 : * baserestrictinfo list from us, it doesn't hide those in joininfo.)
465 : */
466 677980 : if (IsA(node, RestrictInfo))
467 : {
468 39434 : RestrictInfo *oldinfo = (RestrictInfo *) node;
469 39434 : RestrictInfo *newinfo = makeNode(RestrictInfo);
470 :
471 : /* Copy all flat-copiable fields, notably including rinfo_serial */
472 39434 : memcpy(newinfo, oldinfo, sizeof(RestrictInfo));
473 :
474 : /* Recursively fix the clause itself */
475 39434 : newinfo->clause = (Expr *)
476 39434 : adjust_appendrel_attrs_mutator((Node *) oldinfo->clause, context);
477 :
478 : /* and the modified version, if an OR clause */
479 39434 : newinfo->orclause = (Expr *)
480 39434 : adjust_appendrel_attrs_mutator((Node *) oldinfo->orclause, context);
481 :
482 : /* adjust relid sets too */
483 39434 : newinfo->clause_relids = adjust_child_relids(oldinfo->clause_relids,
484 : context->nappinfos,
485 : context->appinfos);
486 39434 : newinfo->required_relids = adjust_child_relids(oldinfo->required_relids,
487 : context->nappinfos,
488 : context->appinfos);
489 39434 : newinfo->outer_relids = adjust_child_relids(oldinfo->outer_relids,
490 : context->nappinfos,
491 : context->appinfos);
492 39434 : newinfo->left_relids = adjust_child_relids(oldinfo->left_relids,
493 : context->nappinfos,
494 : context->appinfos);
495 39434 : newinfo->right_relids = adjust_child_relids(oldinfo->right_relids,
496 : context->nappinfos,
497 : context->appinfos);
498 :
499 : /*
500 : * Reset cached derivative fields, since these might need to have
501 : * different values when considering the child relation. Note we
502 : * don't reset left_ec/right_ec: each child variable is implicitly
503 : * equivalent to its parent, so still a member of the same EC if any.
504 : */
505 39434 : newinfo->eval_cost.startup = -1;
506 39434 : newinfo->norm_selec = -1;
507 39434 : newinfo->outer_selec = -1;
508 39434 : newinfo->left_em = NULL;
509 39434 : newinfo->right_em = NULL;
510 39434 : newinfo->scansel_cache = NIL;
511 39434 : newinfo->left_bucketsize = -1;
512 39434 : newinfo->right_bucketsize = -1;
513 39434 : newinfo->left_mcvfreq = -1;
514 39434 : newinfo->right_mcvfreq = -1;
515 :
516 39434 : return (Node *) newinfo;
517 : }
518 :
519 : /*
520 : * We have to process RelAggInfo nodes specially.
521 : */
522 638546 : if (IsA(node, RelAggInfo))
523 : {
524 18600 : RelAggInfo *oldinfo = (RelAggInfo *) node;
525 18600 : RelAggInfo *newinfo = makeNode(RelAggInfo);
526 :
527 18600 : newinfo->target = (PathTarget *)
528 18600 : adjust_appendrel_attrs_mutator((Node *) oldinfo->target,
529 : context);
530 :
531 18600 : newinfo->agg_input = (PathTarget *)
532 18600 : adjust_appendrel_attrs_mutator((Node *) oldinfo->agg_input,
533 : context);
534 :
535 18600 : newinfo->group_clauses = oldinfo->group_clauses;
536 :
537 18600 : newinfo->group_exprs = (List *)
538 18600 : adjust_appendrel_attrs_mutator((Node *) oldinfo->group_exprs,
539 : context);
540 :
541 18600 : return (Node *) newinfo;
542 : }
543 :
544 : /*
545 : * We have to process PathTarget nodes specially.
546 : */
547 619946 : if (IsA(node, PathTarget))
548 : {
549 37200 : PathTarget *oldtarget = (PathTarget *) node;
550 37200 : PathTarget *newtarget = makeNode(PathTarget);
551 :
552 : /* Copy all flat-copiable fields */
553 37200 : memcpy(newtarget, oldtarget, sizeof(PathTarget));
554 :
555 37200 : newtarget->exprs = (List *)
556 37200 : adjust_appendrel_attrs_mutator((Node *) oldtarget->exprs,
557 : context);
558 :
559 37200 : if (oldtarget->sortgrouprefs)
560 : {
561 37200 : Size nbytes = list_length(oldtarget->exprs) * sizeof(Index);
562 :
563 37200 : newtarget->sortgrouprefs = (Index *) palloc(nbytes);
564 37200 : memcpy(newtarget->sortgrouprefs, oldtarget->sortgrouprefs, nbytes);
565 : }
566 :
567 37200 : return (Node *) newtarget;
568 : }
569 :
570 : /*
571 : * NOTE: we do not need to recurse into sublinks, because they should
572 : * already have been converted to subplans before we see them.
573 : */
574 : Assert(!IsA(node, SubLink));
575 : Assert(!IsA(node, Query));
576 : /* We should never see these Query substructures, either. */
577 : Assert(!IsA(node, RangeTblRef));
578 : Assert(!IsA(node, JoinExpr));
579 :
580 582746 : return expression_tree_mutator(node, adjust_appendrel_attrs_mutator, context);
581 : }
582 :
583 : /*
584 : * adjust_appendrel_attrs_multilevel
585 : * Apply Var translations from an appendrel parent down to a child.
586 : *
587 : * Replace Vars in the "node" expression that reference "parentrel" with
588 : * the appropriate Vars for "childrel". childrel can be more than one
589 : * inheritance level removed from parentrel.
590 : */
591 : Node *
592 47658 : adjust_appendrel_attrs_multilevel(PlannerInfo *root, Node *node,
593 : RelOptInfo *childrel,
594 : RelOptInfo *parentrel)
595 : {
596 : AppendRelInfo **appinfos;
597 : int nappinfos;
598 :
599 : /* Recurse if immediate parent is not the top parent. */
600 47658 : if (childrel->parent != parentrel)
601 : {
602 16336 : if (childrel->parent)
603 16336 : node = adjust_appendrel_attrs_multilevel(root, node,
604 16336 : childrel->parent,
605 : parentrel);
606 : else
607 0 : elog(ERROR, "childrel is not a child of parentrel");
608 : }
609 :
610 : /* Now translate for this child. */
611 47658 : appinfos = find_appinfos_by_relids(root, childrel->relids, &nappinfos);
612 :
613 47658 : node = adjust_appendrel_attrs(root, node, nappinfos, appinfos);
614 :
615 47658 : pfree(appinfos);
616 :
617 47658 : return node;
618 : }
619 :
620 : /*
621 : * Substitute child relids for parent relids in a Relid set. The array of
622 : * appinfos specifies the substitutions to be performed.
623 : */
624 : Relids
625 232262 : adjust_child_relids(Relids relids, int nappinfos, AppendRelInfo **appinfos)
626 : {
627 232262 : Bitmapset *result = NULL;
628 : int cnt;
629 :
630 630766 : for (cnt = 0; cnt < nappinfos; cnt++)
631 : {
632 398504 : AppendRelInfo *appinfo = appinfos[cnt];
633 :
634 : /* Remove parent, add child */
635 398504 : if (bms_is_member(appinfo->parent_relid, relids))
636 : {
637 : /* Make a copy if we are changing the set. */
638 254698 : if (!result)
639 182386 : result = bms_copy(relids);
640 :
641 254698 : result = bms_del_member(result, appinfo->parent_relid);
642 254698 : result = bms_add_member(result, appinfo->child_relid);
643 : }
644 : }
645 :
646 : /* If we made any changes, return the modified copy. */
647 232262 : if (result)
648 182386 : return result;
649 :
650 : /* Otherwise, return the original set without modification. */
651 49876 : return relids;
652 : }
653 :
654 : /*
655 : * Substitute child's relids for parent's relids in a Relid set.
656 : * The childrel can be multiple inheritance levels below the parent.
657 : */
658 : Relids
659 1170 : adjust_child_relids_multilevel(PlannerInfo *root, Relids relids,
660 : RelOptInfo *childrel,
661 : RelOptInfo *parentrel)
662 : {
663 : AppendRelInfo **appinfos;
664 : int nappinfos;
665 :
666 : /*
667 : * If the given relids set doesn't contain any of the parent relids, it
668 : * will remain unchanged.
669 : */
670 1170 : if (!bms_overlap(relids, parentrel->relids))
671 0 : return relids;
672 :
673 : /* Recurse if immediate parent is not the top parent. */
674 1170 : if (childrel->parent != parentrel)
675 : {
676 144 : if (childrel->parent)
677 144 : relids = adjust_child_relids_multilevel(root, relids,
678 144 : childrel->parent,
679 : parentrel);
680 : else
681 0 : elog(ERROR, "childrel is not a child of parentrel");
682 : }
683 :
684 : /* Now translate for this child. */
685 1170 : appinfos = find_appinfos_by_relids(root, childrel->relids, &nappinfos);
686 :
687 1170 : relids = adjust_child_relids(relids, nappinfos, appinfos);
688 :
689 1170 : pfree(appinfos);
690 :
691 1170 : return relids;
692 : }
693 :
694 : /*
695 : * adjust_inherited_attnums
696 : * Translate an integer list of attribute numbers from parent to child.
697 : */
698 : List *
699 5130 : adjust_inherited_attnums(List *attnums, AppendRelInfo *context)
700 : {
701 5130 : List *result = NIL;
702 : ListCell *lc;
703 :
704 : /* This should only happen for an inheritance case, not UNION ALL */
705 : Assert(OidIsValid(context->parent_reloid));
706 :
707 : /* Look up each attribute in the AppendRelInfo's translated_vars list */
708 11450 : foreach(lc, attnums)
709 : {
710 6320 : AttrNumber parentattno = lfirst_int(lc);
711 : Var *childvar;
712 :
713 : /* Look up the translation of this column: it must be a Var */
714 12640 : if (parentattno <= 0 ||
715 6320 : parentattno > list_length(context->translated_vars))
716 0 : elog(ERROR, "attribute %d of relation \"%s\" does not exist",
717 : parentattno, get_rel_name(context->parent_reloid));
718 6320 : childvar = (Var *) list_nth(context->translated_vars, parentattno - 1);
719 6320 : if (childvar == NULL || !IsA(childvar, Var))
720 0 : elog(ERROR, "attribute %d of relation \"%s\" does not exist",
721 : parentattno, get_rel_name(context->parent_reloid));
722 :
723 6320 : result = lappend_int(result, childvar->varattno);
724 : }
725 5130 : return result;
726 : }
727 :
728 : /*
729 : * adjust_inherited_attnums_multilevel
730 : * As above, but traverse multiple inheritance levels as needed.
731 : */
732 : List *
733 5130 : adjust_inherited_attnums_multilevel(PlannerInfo *root, List *attnums,
734 : Index child_relid, Index top_parent_relid)
735 : {
736 5130 : AppendRelInfo *appinfo = root->append_rel_array[child_relid];
737 :
738 5130 : if (!appinfo)
739 0 : elog(ERROR, "child rel %d not found in append_rel_array", child_relid);
740 :
741 : /* Recurse if immediate parent is not the top parent. */
742 5130 : if (appinfo->parent_relid != top_parent_relid)
743 808 : attnums = adjust_inherited_attnums_multilevel(root, attnums,
744 : appinfo->parent_relid,
745 : top_parent_relid);
746 :
747 : /* Now translate for this child */
748 5130 : return adjust_inherited_attnums(attnums, appinfo);
749 : }
750 :
751 : /*
752 : * get_translated_update_targetlist
753 : * Get the processed_tlist of an UPDATE query, translated as needed to
754 : * match a child target relation.
755 : *
756 : * Optionally also return the list of target column numbers translated
757 : * to this target relation. (The resnos in processed_tlist MUST NOT be
758 : * relied on for this purpose.)
759 : */
760 : void
761 100 : get_translated_update_targetlist(PlannerInfo *root, Index relid,
762 : List **processed_tlist, List **update_colnos)
763 : {
764 : /* This is pretty meaningless for commands other than UPDATE. */
765 : Assert(root->parse->commandType == CMD_UPDATE);
766 100 : if (relid == root->parse->resultRelation)
767 : {
768 : /*
769 : * Non-inheritance case, so it's easy. The caller might be expecting
770 : * a tree it can scribble on, though, so copy.
771 : */
772 66 : *processed_tlist = copyObject(root->processed_tlist);
773 66 : if (update_colnos)
774 66 : *update_colnos = copyObject(root->update_colnos);
775 : }
776 : else
777 : {
778 : Assert(bms_is_member(relid, root->all_result_relids));
779 34 : *processed_tlist = (List *)
780 34 : adjust_appendrel_attrs_multilevel(root,
781 34 : (Node *) root->processed_tlist,
782 : find_base_rel(root, relid),
783 34 : find_base_rel(root, root->parse->resultRelation));
784 34 : if (update_colnos)
785 34 : *update_colnos =
786 34 : adjust_inherited_attnums_multilevel(root, root->update_colnos,
787 : relid,
788 34 : root->parse->resultRelation);
789 : }
790 100 : }
791 :
792 : /*
793 : * find_appinfos_by_relids
794 : * Find AppendRelInfo structures for base relations listed in relids.
795 : *
796 : * The relids argument is typically a join relation's relids, which can
797 : * include outer-join RT indexes in addition to baserels. We silently
798 : * ignore the outer joins.
799 : *
800 : * The AppendRelInfos are returned in an array, which can be pfree'd by the
801 : * caller. *nappinfos is set to the number of entries in the array.
802 : */
803 : AppendRelInfo **
804 100380 : find_appinfos_by_relids(PlannerInfo *root, Relids relids, int *nappinfos)
805 : {
806 : AppendRelInfo **appinfos;
807 100380 : int cnt = 0;
808 : int i;
809 :
810 : /* Allocate an array that's certainly big enough */
811 : appinfos = (AppendRelInfo **)
812 100380 : palloc(sizeof(AppendRelInfo *) * bms_num_members(relids));
813 :
814 100380 : i = -1;
815 252470 : while ((i = bms_next_member(relids, i)) >= 0)
816 : {
817 152090 : AppendRelInfo *appinfo = root->append_rel_array[i];
818 :
819 152090 : if (!appinfo)
820 : {
821 : /* Probably i is an OJ index, but let's check */
822 3576 : if (find_base_rel_ignore_join(root, i) == NULL)
823 3576 : continue;
824 : /* It's a base rel, but we lack an append_rel_array entry */
825 0 : elog(ERROR, "child rel %d not found in append_rel_array", i);
826 : }
827 :
828 148514 : appinfos[cnt++] = appinfo;
829 : }
830 100380 : *nappinfos = cnt;
831 100380 : return appinfos;
832 : }
833 :
834 :
835 : /*****************************************************************************
836 : *
837 : * ROW-IDENTITY VARIABLE MANAGEMENT
838 : *
839 : * This code lacks a good home, perhaps. We choose to keep it here because
840 : * adjust_appendrel_attrs_mutator() is its principal co-conspirator. That
841 : * function does most of what is needed to expand ROWID_VAR Vars into the
842 : * right things.
843 : *
844 : *****************************************************************************/
845 :
846 : /*
847 : * add_row_identity_var
848 : * Register a row-identity column to be used in UPDATE/DELETE/MERGE.
849 : *
850 : * The Var must be equal(), aside from varno, to any other row-identity
851 : * column with the same rowid_name. Thus, for example, "wholerow"
852 : * row identities had better use vartype == RECORDOID.
853 : *
854 : * rtindex is currently redundant with rowid_var->varno, but we specify
855 : * it as a separate parameter in case this is ever generalized to support
856 : * non-Var expressions. (We could reasonably handle expressions over
857 : * Vars of the specified rtindex, but for now that seems unnecessary.)
858 : */
859 : void
860 28302 : add_row_identity_var(PlannerInfo *root, Var *orig_var,
861 : Index rtindex, const char *rowid_name)
862 : {
863 : TargetEntry *tle;
864 : Var *rowid_var;
865 : RowIdentityVarInfo *ridinfo;
866 : ListCell *lc;
867 :
868 : /* For now, the argument must be just a Var of the given rtindex */
869 : Assert(IsA(orig_var, Var));
870 : Assert(orig_var->varno == rtindex);
871 : Assert(orig_var->varlevelsup == 0);
872 : Assert(orig_var->varnullingrels == NULL);
873 :
874 : /*
875 : * If we're doing non-inherited UPDATE/DELETE/MERGE, there's little need
876 : * for ROWID_VAR shenanigans. Just shove the presented Var into the
877 : * processed_tlist, and we're done.
878 : */
879 28302 : if (rtindex == root->parse->resultRelation)
880 : {
881 17208 : tle = makeTargetEntry((Expr *) orig_var,
882 17208 : list_length(root->processed_tlist) + 1,
883 : pstrdup(rowid_name),
884 : true);
885 17208 : root->processed_tlist = lappend(root->processed_tlist, tle);
886 17208 : return;
887 : }
888 :
889 : /*
890 : * Otherwise, rtindex should reference a leaf target relation that's being
891 : * added to the query during expand_inherited_rtentry().
892 : */
893 : Assert(bms_is_member(rtindex, root->leaf_result_relids));
894 : Assert(root->append_rel_array[rtindex] != NULL);
895 :
896 : /*
897 : * We have to find a matching RowIdentityVarInfo, or make one if there is
898 : * none. To allow using equal() to match the vars, change the varno to
899 : * ROWID_VAR, leaving all else alone.
900 : */
901 11094 : rowid_var = copyObject(orig_var);
902 : /* This could eventually become ChangeVarNodes() */
903 11094 : rowid_var->varno = ROWID_VAR;
904 :
905 : /* Look for an existing row-id column of the same name */
906 16768 : foreach(lc, root->row_identity_vars)
907 : {
908 10950 : ridinfo = (RowIdentityVarInfo *) lfirst(lc);
909 10950 : if (strcmp(rowid_name, ridinfo->rowidname) != 0)
910 5674 : continue;
911 5276 : if (equal(rowid_var, ridinfo->rowidvar))
912 : {
913 : /* Found a match; we need only record that rtindex needs it too */
914 5276 : ridinfo->rowidrels = bms_add_member(ridinfo->rowidrels, rtindex);
915 5276 : return;
916 : }
917 : else
918 : {
919 : /* Ooops, can't handle this */
920 0 : elog(ERROR, "conflicting uses of row-identity name \"%s\"",
921 : rowid_name);
922 : }
923 : }
924 :
925 : /* No request yet, so add a new RowIdentityVarInfo */
926 5818 : ridinfo = makeNode(RowIdentityVarInfo);
927 5818 : ridinfo->rowidvar = copyObject(rowid_var);
928 : /* for the moment, estimate width using just the datatype info */
929 5818 : ridinfo->rowidwidth = get_typavgwidth(exprType((Node *) rowid_var),
930 : exprTypmod((Node *) rowid_var));
931 5818 : ridinfo->rowidname = pstrdup(rowid_name);
932 5818 : ridinfo->rowidrels = bms_make_singleton(rtindex);
933 :
934 5818 : root->row_identity_vars = lappend(root->row_identity_vars, ridinfo);
935 :
936 : /* Change rowid_var into a reference to this row_identity_vars entry */
937 5818 : rowid_var->varattno = list_length(root->row_identity_vars);
938 :
939 : /* Push the ROWID_VAR reference variable into processed_tlist */
940 5818 : tle = makeTargetEntry((Expr *) rowid_var,
941 5818 : list_length(root->processed_tlist) + 1,
942 : pstrdup(rowid_name),
943 : true);
944 5818 : root->processed_tlist = lappend(root->processed_tlist, tle);
945 : }
946 :
947 : /*
948 : * add_row_identity_columns
949 : *
950 : * This function adds the row identity columns needed by the core code.
951 : * FDWs might call add_row_identity_var() for themselves to add nonstandard
952 : * columns. (Duplicate requests are fine.)
953 : */
954 : void
955 22868 : add_row_identity_columns(PlannerInfo *root, Index rtindex,
956 : RangeTblEntry *target_rte,
957 : Relation target_relation)
958 : {
959 22868 : CmdType commandType = root->parse->commandType;
960 22868 : char relkind = target_relation->rd_rel->relkind;
961 : Var *var;
962 :
963 : Assert(commandType == CMD_UPDATE || commandType == CMD_DELETE || commandType == CMD_MERGE);
964 :
965 22868 : if (relkind == RELKIND_RELATION ||
966 716 : relkind == RELKIND_MATVIEW ||
967 : relkind == RELKIND_PARTITIONED_TABLE)
968 : {
969 : /*
970 : * Emit CTID so that executor can find the row to merge, update or
971 : * delete.
972 : */
973 22188 : var = makeVar(rtindex,
974 : SelfItemPointerAttributeNumber,
975 : TIDOID,
976 : -1,
977 : InvalidOid,
978 : 0);
979 22188 : add_row_identity_var(root, var, rtindex, "ctid");
980 : }
981 680 : else if (relkind == RELKIND_FOREIGN_TABLE)
982 : {
983 : /*
984 : * Let the foreign table's FDW add whatever junk TLEs it wants.
985 : */
986 : FdwRoutine *fdwroutine;
987 :
988 386 : fdwroutine = GetFdwRoutineForRelation(target_relation, false);
989 :
990 386 : if (fdwroutine->AddForeignUpdateTargets != NULL)
991 378 : fdwroutine->AddForeignUpdateTargets(root, rtindex,
992 : target_rte, target_relation);
993 :
994 : /*
995 : * For UPDATE, we need to make the FDW fetch unchanged columns by
996 : * asking it to fetch a whole-row Var. That's because the top-level
997 : * targetlist only contains entries for changed columns, but
998 : * ExecUpdate will need to build the complete new tuple. (Actually,
999 : * we only really need this in UPDATEs that are not pushed to the
1000 : * remote side, but it's hard to tell if that will be the case at the
1001 : * point when this function is called.)
1002 : *
1003 : * We will also need the whole row if there are any row triggers, so
1004 : * that the executor will have the "old" row to pass to the trigger.
1005 : * Alas, this misses system columns.
1006 : */
1007 386 : if (commandType == CMD_UPDATE ||
1008 172 : (target_relation->trigdesc &&
1009 30 : (target_relation->trigdesc->trig_delete_after_row ||
1010 18 : target_relation->trigdesc->trig_delete_before_row)))
1011 : {
1012 230 : var = makeVar(rtindex,
1013 : InvalidAttrNumber,
1014 : RECORDOID,
1015 : -1,
1016 : InvalidOid,
1017 : 0);
1018 230 : add_row_identity_var(root, var, rtindex, "wholerow");
1019 : }
1020 : }
1021 22868 : }
1022 :
1023 : /*
1024 : * distribute_row_identity_vars
1025 : *
1026 : * After we have finished identifying all the row identity columns
1027 : * needed by an inherited UPDATE/DELETE/MERGE query, make sure that
1028 : * these columns will be generated by all the target relations.
1029 : *
1030 : * This is more or less like what build_base_rel_tlists() does,
1031 : * except that it would not understand what to do with ROWID_VAR Vars.
1032 : * Since that function runs before inheritance relations are expanded,
1033 : * it will never see any such Vars anyway.
1034 : */
1035 : void
1036 324430 : distribute_row_identity_vars(PlannerInfo *root)
1037 : {
1038 324430 : Query *parse = root->parse;
1039 324430 : int result_relation = parse->resultRelation;
1040 : RangeTblEntry *target_rte;
1041 : RelOptInfo *target_rel;
1042 : ListCell *lc;
1043 :
1044 : /*
1045 : * There's nothing to do if this isn't an inherited UPDATE/DELETE/MERGE.
1046 : */
1047 324430 : if (parse->commandType != CMD_UPDATE && parse->commandType != CMD_DELETE &&
1048 305990 : parse->commandType != CMD_MERGE)
1049 : {
1050 : Assert(root->row_identity_vars == NIL);
1051 304208 : return;
1052 : }
1053 20222 : target_rte = rt_fetch(result_relation, parse->rtable);
1054 20222 : if (!target_rte->inh)
1055 : {
1056 : Assert(root->row_identity_vars == NIL);
1057 17324 : return;
1058 : }
1059 :
1060 : /*
1061 : * Ordinarily, we expect that leaf result relation(s) will have added some
1062 : * ROWID_VAR Vars to the query. However, it's possible that constraint
1063 : * exclusion suppressed every leaf relation. The executor will get upset
1064 : * if the plan has no row identity columns at all, even though it will
1065 : * certainly process no rows. Handle this edge case by re-opening the top
1066 : * result relation and adding the row identity columns it would have used,
1067 : * as preprocess_targetlist() would have done if it weren't marked "inh".
1068 : * Then re-run build_base_rel_tlists() to ensure that the added columns
1069 : * get propagated to the relation's reltarget. (This is a bit ugly, but
1070 : * it seems better to confine the ugliness and extra cycles to this
1071 : * unusual corner case.)
1072 : */
1073 2898 : if (root->row_identity_vars == NIL)
1074 : {
1075 : Relation target_relation;
1076 :
1077 30 : target_relation = table_open(target_rte->relid, NoLock);
1078 30 : add_row_identity_columns(root, result_relation,
1079 : target_rte, target_relation);
1080 30 : table_close(target_relation, NoLock);
1081 30 : build_base_rel_tlists(root, root->processed_tlist);
1082 : /* There are no ROWID_VAR Vars in this case, so we're done. */
1083 30 : return;
1084 : }
1085 :
1086 : /*
1087 : * Dig through the processed_tlist to find the ROWID_VAR reference Vars,
1088 : * and forcibly copy them into the reltarget list of the topmost target
1089 : * relation. That's sufficient because they'll be copied to the
1090 : * individual leaf target rels (with appropriate translation) later,
1091 : * during appendrel expansion --- see set_append_rel_size().
1092 : */
1093 2868 : target_rel = find_base_rel(root, result_relation);
1094 :
1095 12032 : foreach(lc, root->processed_tlist)
1096 : {
1097 9164 : TargetEntry *tle = lfirst(lc);
1098 9164 : Var *var = (Var *) tle->expr;
1099 :
1100 9164 : if (var && IsA(var, Var) && var->varno == ROWID_VAR)
1101 : {
1102 5818 : target_rel->reltarget->exprs =
1103 5818 : lappend(target_rel->reltarget->exprs, copyObject(var));
1104 : /* reltarget cost and width will be computed later */
1105 : }
1106 : }
1107 : }
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