Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * rewriteHandler.c
4 : : * Primary module of query rewriter.
5 : : *
6 : : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
7 : : * Portions Copyright (c) 1994, Regents of the University of California
8 : : *
9 : : * IDENTIFICATION
10 : : * src/backend/rewrite/rewriteHandler.c
11 : : *
12 : : * NOTES
13 : : * Some of the terms used in this file are of historic nature: "retrieve"
14 : : * was the PostQUEL keyword for what today is SELECT. "RIR" stands for
15 : : * "Retrieve-Instead-Retrieve", that is an ON SELECT DO INSTEAD SELECT rule
16 : : * (which has to be unconditional and where only one rule can exist on each
17 : : * relation).
18 : : *
19 : : *-------------------------------------------------------------------------
20 : : */
21 : : #include "postgres.h"
22 : :
23 : : #include "access/relation.h"
24 : : #include "access/sysattr.h"
25 : : #include "access/table.h"
26 : : #include "catalog/dependency.h"
27 : : #include "commands/trigger.h"
28 : : #include "executor/executor.h"
29 : : #include "foreign/fdwapi.h"
30 : : #include "miscadmin.h"
31 : : #include "nodes/makefuncs.h"
32 : : #include "nodes/nodeFuncs.h"
33 : : #include "optimizer/optimizer.h"
34 : : #include "parser/analyze.h"
35 : : #include "parser/parse_coerce.h"
36 : : #include "parser/parse_relation.h"
37 : : #include "parser/parsetree.h"
38 : : #include "rewrite/rewriteDefine.h"
39 : : #include "rewrite/rewriteHandler.h"
40 : : #include "rewrite/rewriteManip.h"
41 : : #include "rewrite/rewriteSearchCycle.h"
42 : : #include "rewrite/rowsecurity.h"
43 : : #include "tcop/tcopprot.h"
44 : : #include "utils/builtins.h"
45 : : #include "utils/lsyscache.h"
46 : : #include "utils/rel.h"
47 : :
48 : :
49 : : /* We use a list of these to detect recursion in RewriteQuery */
50 : : typedef struct rewrite_event
51 : : {
52 : : Oid relation; /* OID of relation having rules */
53 : : CmdType event; /* type of rule being fired */
54 : : } rewrite_event;
55 : :
56 : : typedef struct acquireLocksOnSubLinks_context
57 : : {
58 : : bool for_execute; /* AcquireRewriteLocks' forExecute param */
59 : : } acquireLocksOnSubLinks_context;
60 : :
61 : : typedef struct fireRIRonSubLink_context
62 : : {
63 : : List *activeRIRs;
64 : : bool hasRowSecurity;
65 : : } fireRIRonSubLink_context;
66 : :
67 : : static bool acquireLocksOnSubLinks(Node *node,
68 : : acquireLocksOnSubLinks_context *context);
69 : : static Query *rewriteRuleAction(Query *parsetree,
70 : : Query *rule_action,
71 : : Node *rule_qual,
72 : : int rt_index,
73 : : CmdType event,
74 : : bool *returning_flag);
75 : : static List *adjustJoinTreeList(Query *parsetree, bool removert, int rt_index);
76 : : static List *rewriteTargetListIU(List *targetList,
77 : : CmdType commandType,
78 : : OverridingKind override,
79 : : Relation target_relation,
80 : : RangeTblEntry *values_rte,
81 : : int values_rte_index,
82 : : Bitmapset **unused_values_attrnos);
83 : : static TargetEntry *process_matched_tle(TargetEntry *src_tle,
84 : : TargetEntry *prior_tle,
85 : : const char *attrName);
86 : : static Node *get_assignment_input(Node *node);
87 : : static Bitmapset *findDefaultOnlyColumns(RangeTblEntry *rte);
88 : : static bool rewriteValuesRTE(Query *parsetree, RangeTblEntry *rte, int rti,
89 : : Relation target_relation,
90 : : Bitmapset *unused_cols);
91 : : static void rewriteValuesRTEToNulls(Query *parsetree, RangeTblEntry *rte);
92 : : static void markQueryForLocking(Query *qry, Node *jtnode,
93 : : LockClauseStrength strength, LockWaitPolicy waitPolicy,
94 : : bool pushedDown);
95 : : static List *matchLocks(CmdType event, Relation relation,
96 : : int varno, Query *parsetree, bool *hasUpdate);
97 : : static Query *fireRIRrules(Query *parsetree, List *activeRIRs);
98 : : static Bitmapset *adjust_view_column_set(Bitmapset *cols, List *targetlist);
99 : : static List *get_generated_columns(Relation rel, int rt_index, bool include_stored);
100 : :
101 : :
102 : : /*
103 : : * AcquireRewriteLocks -
104 : : * Acquire suitable locks on all the relations mentioned in the Query.
105 : : * These locks will ensure that the relation schemas don't change under us
106 : : * while we are rewriting, planning, and executing the query.
107 : : *
108 : : * Caution: this may modify the querytree, therefore caller should usually
109 : : * have done a copyObject() to make a writable copy of the querytree in the
110 : : * current memory context.
111 : : *
112 : : * forExecute indicates that the query is about to be executed. If so,
113 : : * we'll acquire the lock modes specified in the RTE rellockmode fields.
114 : : * If forExecute is false, AccessShareLock is acquired on all relations.
115 : : * This case is suitable for ruleutils.c, for example, where we only need
116 : : * schema stability and we don't intend to actually modify any relations.
117 : : *
118 : : * forUpdatePushedDown indicates that a pushed-down FOR [KEY] UPDATE/SHARE
119 : : * applies to the current subquery, requiring all rels to be opened with at
120 : : * least RowShareLock. This should always be false at the top of the
121 : : * recursion. When it is true, we adjust RTE rellockmode fields to reflect
122 : : * the higher lock level. This flag is ignored if forExecute is false.
123 : : *
124 : : * A secondary purpose of this routine is to fix up JOIN RTE references to
125 : : * dropped columns (see details below). Such RTEs are modified in-place.
126 : : *
127 : : * This processing can, and for efficiency's sake should, be skipped when the
128 : : * querytree has just been built by the parser: parse analysis already got
129 : : * all the same locks we'd get here, and the parser will have omitted dropped
130 : : * columns from JOINs to begin with. But we must do this whenever we are
131 : : * dealing with a querytree produced earlier than the current command.
132 : : *
133 : : * About JOINs and dropped columns: although the parser never includes an
134 : : * already-dropped column in a JOIN RTE's alias var list, it is possible for
135 : : * such a list in a stored rule to include references to dropped columns.
136 : : * (If the column is not explicitly referenced anywhere else in the query,
137 : : * the dependency mechanism won't consider it used by the rule and so won't
138 : : * prevent the column drop.) To support get_rte_attribute_is_dropped(), we
139 : : * replace join alias vars that reference dropped columns with null pointers.
140 : : *
141 : : * (In PostgreSQL 8.0, we did not do this processing but instead had
142 : : * get_rte_attribute_is_dropped() recurse to detect dropped columns in joins.
143 : : * That approach had horrible performance unfortunately; in particular
144 : : * construction of a nested join was O(N^2) in the nesting depth.)
145 : : */
146 : : void
4581 tgl@sss.pgh.pa.us 147 :CBC 27511 : AcquireRewriteLocks(Query *parsetree,
148 : : bool forExecute,
149 : : bool forUpdatePushedDown)
150 : : {
151 : : ListCell *l;
152 : : int rt_index;
153 : : acquireLocksOnSubLinks_context context;
154 : :
155 : 27511 : context.for_execute = forExecute;
156 : :
157 : : /*
158 : : * First, process RTEs of the current query level.
159 : : */
7779 160 : 27511 : rt_index = 0;
161 [ + + + + : 89140 : foreach(l, parsetree->rtable)
+ + ]
162 : : {
163 : 61629 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
164 : : Relation rel;
165 : : LOCKMODE lockmode;
166 : : List *newaliasvars;
167 : : Index curinputvarno;
168 : : RangeTblEntry *curinputrte;
169 : : ListCell *ll;
170 : :
171 : 61629 : ++rt_index;
172 [ + + + + ]: 61629 : switch (rte->rtekind)
173 : : {
174 : 34908 : case RTE_RELATION:
175 : :
176 : : /*
177 : : * Grab the appropriate lock type for the relation, and do not
178 : : * release it until end of transaction. This protects the
179 : : * rewriter, planner, and executor against schema changes
180 : : * mid-query.
181 : : *
182 : : * If forExecute is false, ignore rellockmode and just use
183 : : * AccessShareLock.
184 : : */
4581 185 [ + + ]: 34908 : if (!forExecute)
186 : 4714 : lockmode = AccessShareLock;
2912 187 [ + + ]: 30194 : else if (forUpdatePushedDown)
188 : : {
189 : : /* Upgrade RTE's lock mode to reflect pushed-down lock */
190 [ + - ]: 64 : if (rte->rellockmode == AccessShareLock)
191 : 64 : rte->rellockmode = RowShareLock;
2910 192 : 64 : lockmode = rte->rellockmode;
193 : : }
194 : : else
195 : 30130 : lockmode = rte->rellockmode;
196 : :
193 peter@eisentraut.org 197 : 34908 : rel = relation_open(rte->relid, lockmode);
198 : :
199 : : /*
200 : : * While we have the relation open, update the RTE's relkind,
201 : : * just in case it changed since this rule was made.
202 : : */
5689 tgl@sss.pgh.pa.us 203 : 34908 : rte->relkind = rel->rd_rel->relkind;
204 : :
193 peter@eisentraut.org 205 : 34908 : relation_close(rel, NoLock);
7779 tgl@sss.pgh.pa.us 206 : 34908 : break;
207 : :
208 : 15140 : case RTE_JOIN:
209 : :
210 : : /*
211 : : * Scan the join's alias var list to see if any columns have
212 : : * been dropped, and if so replace those Vars with null
213 : : * pointers.
214 : : *
215 : : * Since a join has only two inputs, we can expect to see
216 : : * multiple references to the same input RTE; optimize away
217 : : * multiple fetches.
218 : : */
219 : 15140 : newaliasvars = NIL;
7778 220 : 15140 : curinputvarno = 0;
221 : 15140 : curinputrte = NULL;
7779 222 [ + - + + : 610249 : foreach(ll, rte->joinaliasvars)
+ + ]
223 : : {
4807 224 : 595109 : Var *aliasitem = (Var *) lfirst(ll);
225 : 595109 : Var *aliasvar = aliasitem;
226 : :
227 : : /* Look through any implicit coercion */
228 : 595109 : aliasvar = (Var *) strip_implicit_coercions((Node *) aliasvar);
229 : :
230 : : /*
231 : : * If the list item isn't a simple Var, then it must
232 : : * represent a merged column, ie a USING column, and so it
233 : : * couldn't possibly be dropped, since it's referenced in
234 : : * the join clause. (Conceivably it could also be a null
235 : : * pointer already? But that's OK too.)
236 : : */
237 [ + - + + ]: 595109 : if (aliasvar && IsA(aliasvar, Var))
238 : : {
239 : : /*
240 : : * The elements of an alias list have to refer to
241 : : * earlier RTEs of the same rtable, because that's the
242 : : * order the planner builds things in. So we already
243 : : * processed the referenced RTE, and so it's safe to
244 : : * use get_rte_attribute_is_dropped on it. (This might
245 : : * not hold after rewriting or planning, but it's OK
246 : : * to assume here.)
247 : : */
7779 248 [ - + ]: 594993 : Assert(aliasvar->varlevelsup == 0);
7778 249 [ + + ]: 594993 : if (aliasvar->varno != curinputvarno)
250 : : {
251 : 40242 : curinputvarno = aliasvar->varno;
252 [ - + ]: 40242 : if (curinputvarno >= rt_index)
7778 tgl@sss.pgh.pa.us 253 [ # # ]:UBC 0 : elog(ERROR, "unexpected varno %d in JOIN RTE %d",
254 : : curinputvarno, rt_index);
7778 tgl@sss.pgh.pa.us 255 :CBC 40242 : curinputrte = rt_fetch(curinputvarno,
256 : : parsetree->rtable);
257 : : }
258 [ + + ]: 594993 : if (get_rte_attribute_is_dropped(curinputrte,
259 : 594993 : aliasvar->varattno))
260 : : {
261 : : /* Replace the join alias item with a NULL */
4807 262 : 4 : aliasitem = NULL;
263 : : }
264 : : }
265 : 595109 : newaliasvars = lappend(newaliasvars, aliasitem);
266 : : }
7779 267 : 15140 : rte->joinaliasvars = newaliasvars;
268 : 15140 : break;
269 : :
270 : 4712 : case RTE_SUBQUERY:
271 : :
272 : : /*
273 : : * The subquery RTE itself is all right, but we have to
274 : : * recurse to process the represented subquery.
275 : : */
6171 276 : 4712 : AcquireRewriteLocks(rte->subquery,
277 : : forExecute,
278 [ + - - + ]: 9424 : (forUpdatePushedDown ||
3378 279 : 9424 : get_parse_rowmark(parsetree, rt_index) != NULL));
7779 280 : 4712 : break;
281 : :
282 : 6869 : default:
283 : : /* ignore other types of RTEs */
284 : 6869 : break;
285 : : }
286 : : }
287 : :
288 : : /* Recurse into subqueries in WITH */
6560 289 [ + + + + : 27712 : foreach(l, parsetree->cteList)
+ + ]
290 : : {
291 : 201 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(l);
292 : :
4581 293 : 201 : AcquireRewriteLocks((Query *) cte->ctequery, forExecute, false);
294 : : }
295 : :
296 : : /*
297 : : * Recurse into sublink subqueries, too. But we already did the ones in
298 : : * the rtable and cteList.
299 : : */
7779 300 [ + + ]: 27511 : if (parsetree->hasSubLinks)
4581 301 : 1367 : query_tree_walker(parsetree, acquireLocksOnSubLinks, &context,
302 : : QTW_IGNORE_RC_SUBQUERIES);
7779 303 : 27511 : }
304 : :
305 : : /*
306 : : * Walker to find sublink subqueries for AcquireRewriteLocks
307 : : */
308 : : static bool
4581 309 : 130392 : acquireLocksOnSubLinks(Node *node, acquireLocksOnSubLinks_context *context)
310 : : {
7779 311 [ + + ]: 130392 : if (node == NULL)
312 : 25202 : return false;
313 [ + + ]: 105190 : if (IsA(node, SubLink))
314 : : {
315 : 2899 : SubLink *sub = (SubLink *) node;
316 : :
317 : : /* Do what we came for */
4581 318 : 2899 : AcquireRewriteLocks((Query *) sub->subselect,
319 : 2899 : context->for_execute,
320 : : false);
321 : : /* Fall through to process lefthand args of SubLink */
322 : : }
323 : :
324 : : /*
325 : : * Do NOT recurse into Query nodes, because AcquireRewriteLocks already
326 : : * processed subselects of subselects for us.
327 : : */
7779 328 : 105190 : return expression_tree_walker(node, acquireLocksOnSubLinks, context);
329 : : }
330 : :
331 : :
332 : : /*
333 : : * rewriteRuleAction -
334 : : * Rewrite the rule action with appropriate qualifiers (taken from
335 : : * the triggering query).
336 : : *
337 : : * Input arguments:
338 : : * parsetree - original query
339 : : * rule_action - one action (query) of a rule
340 : : * rule_qual - WHERE condition of rule, or NULL if unconditional
341 : : * rt_index - RT index of result relation in original query
342 : : * event - type of rule event
343 : : * Output arguments:
344 : : * *returning_flag - set true if we rewrite RETURNING clause in rule_action
345 : : * (must be initialized to false)
346 : : * Return value:
347 : : * rewritten form of rule_action
348 : : */
349 : : static Query *
9230 350 : 976 : rewriteRuleAction(Query *parsetree,
351 : : Query *rule_action,
352 : : Node *rule_qual,
353 : : int rt_index,
354 : : CmdType event,
355 : : bool *returning_flag)
356 : : {
357 : : int current_varno,
358 : : new_varno;
359 : : int rt_length;
360 : : Query *sub_action;
361 : : Query **sub_action_ptr;
362 : : acquireLocksOnSubLinks_context context;
363 : : ListCell *lc;
364 : :
4581 365 : 976 : context.for_execute = true;
366 : :
367 : : /*
368 : : * Make modifiable copies of rule action and qual (what we're passed are
369 : : * the stored versions in the relcache; don't touch 'em!).
370 : : */
3482 peter_e@gmx.net 371 : 976 : rule_action = copyObject(rule_action);
372 : 976 : rule_qual = copyObject(rule_qual);
373 : :
374 : : /*
375 : : * Acquire necessary locks and fix any deleted JOIN RTE entries.
376 : : */
4581 tgl@sss.pgh.pa.us 377 : 976 : AcquireRewriteLocks(rule_action, true, false);
378 : 976 : (void) acquireLocksOnSubLinks(rule_qual, &context);
379 : :
9230 380 : 976 : current_varno = rt_index;
8148 neilc@samurai.com 381 : 976 : rt_length = list_length(parsetree->rtable);
9230 tgl@sss.pgh.pa.us 382 : 976 : new_varno = PRS2_NEW_VARNO + rt_length;
383 : :
384 : : /*
385 : : * Adjust rule action and qual to offset its varnos, so that we can merge
386 : : * its rtable with the main parsetree's rtable.
387 : : *
388 : : * If the rule action is an INSERT...SELECT, the OLD/NEW rtable entries
389 : : * will be in the SELECT part, and we have to modify that rather than the
390 : : * top-level INSERT (kluge!).
391 : : */
392 : 976 : sub_action = getInsertSelectQuery(rule_action, &sub_action_ptr);
393 : :
9420 394 : 976 : OffsetVarNodes((Node *) sub_action, rt_length, 0);
9230 395 : 976 : OffsetVarNodes(rule_qual, rt_length, 0);
396 : : /* but references to OLD should point at original rt_index */
9420 397 : 976 : ChangeVarNodes((Node *) sub_action,
398 : : PRS2_OLD_VARNO + rt_length, rt_index, 0);
9230 399 : 976 : ChangeVarNodes(rule_qual,
400 : : PRS2_OLD_VARNO + rt_length, rt_index, 0);
401 : :
402 : : /*
403 : : * Mark any subquery RTEs in the rule action as LATERAL if they contain
404 : : * Vars referring to the current query level (references to NEW/OLD).
405 : : * Those really are lateral references, but we've historically not
406 : : * required users to mark such subqueries with LATERAL explicitly. But
407 : : * the planner will complain if such Vars exist in a non-LATERAL subquery,
408 : : * so we have to fix things up here.
409 : : */
1303 dean.a.rasheed@gmail 410 [ + + + + : 3884 : foreach(lc, sub_action->rtable)
+ + ]
411 : : {
412 : 2908 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
413 : :
414 [ + + + - : 2916 : if (rte->rtekind == RTE_SUBQUERY && !rte->lateral &&
+ - ]
415 : 8 : contain_vars_of_level((Node *) rte->subquery, 1))
416 : 8 : rte->lateral = true;
417 : : }
418 : :
419 : : /*
420 : : * Generate expanded rtable consisting of main parsetree's rtable plus
421 : : * rule action's rtable; this becomes the complete rtable for the rule
422 : : * action. Some of the entries may be unused after we finish rewriting,
423 : : * but we leave them all in place to avoid having to adjust the query's
424 : : * varnos. RT entries that are not referenced in the completed jointree
425 : : * will be ignored by the planner, so they do not affect query semantics.
426 : : *
427 : : * Also merge RTEPermissionInfo lists to ensure that all permissions are
428 : : * checked correctly.
429 : : *
430 : : * If the rule is INSTEAD, then the original query won't be executed at
431 : : * all, and so its rteperminfos must be preserved so that the executor
432 : : * will do the correct permissions checks on the relations referenced in
433 : : * it. This allows us to check that the caller has, say, insert-permission
434 : : * on a view, when the view is not semantically referenced at all in the
435 : : * resulting query.
436 : : *
437 : : * When a rule is not INSTEAD, the permissions checks done using the
438 : : * copied entries will be redundant with those done during execution of
439 : : * the original query, but we don't bother to treat that case differently.
440 : : *
441 : : * NOTE: because planner will destructively alter rtable and rteperminfos,
442 : : * we must ensure that rule action's lists are separate and shares no
443 : : * substructure with the main query's lists. Hence do a deep copy here
444 : : * for both.
445 : : */
446 : : {
1384 alvherre@alvh.no-ip. 447 : 976 : List *rtable_tail = sub_action->rtable;
448 : 976 : List *perminfos_tail = sub_action->rteperminfos;
449 : :
450 : : /*
451 : : * RewriteQuery relies on the fact that RT entries from the original
452 : : * query appear at the start of the expanded rtable, so we put the
453 : : * action's original table at the end of the list.
454 : : */
455 : 976 : sub_action->rtable = copyObject(parsetree->rtable);
456 : 976 : sub_action->rteperminfos = copyObject(parsetree->rteperminfos);
457 : 976 : CombineRangeTables(&sub_action->rtable, &sub_action->rteperminfos,
458 : : rtable_tail, perminfos_tail);
459 : : }
460 : :
461 : : /*
462 : : * There could have been some SubLinks in parsetree's rtable, in which
463 : : * case we'd better mark the sub_action correctly.
464 : : */
6570 tgl@sss.pgh.pa.us 465 [ + + + - ]: 976 : if (parsetree->hasSubLinks && !sub_action->hasSubLinks)
466 : : {
467 [ + - + + : 60 : foreach(lc, parsetree->rtable)
+ + ]
468 : : {
469 : 40 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
470 : :
471 [ + - - - : 40 : switch (rte->rtekind)
+ ]
472 : : {
4075 473 : 36 : case RTE_RELATION:
474 : 36 : sub_action->hasSubLinks =
475 : 36 : checkExprHasSubLink((Node *) rte->tablesample);
476 : 36 : break;
6570 tgl@sss.pgh.pa.us 477 :UBC 0 : case RTE_FUNCTION:
478 : 0 : sub_action->hasSubLinks =
4686 479 : 0 : checkExprHasSubLink((Node *) rte->functions);
6570 480 : 0 : break;
3483 alvherre@alvh.no-ip. 481 : 0 : case RTE_TABLEFUNC:
482 : 0 : sub_action->hasSubLinks =
483 : 0 : checkExprHasSubLink((Node *) rte->tablefunc);
484 : 0 : break;
6570 tgl@sss.pgh.pa.us 485 : 0 : case RTE_VALUES:
486 : 0 : sub_action->hasSubLinks =
487 : 0 : checkExprHasSubLink((Node *) rte->values_lists);
488 : 0 : break;
6570 tgl@sss.pgh.pa.us 489 :CBC 4 : default:
490 : : /* other RTE types don't contain bare expressions */
491 : 4 : break;
492 : : }
1195 493 : 40 : sub_action->hasSubLinks |=
494 : 40 : checkExprHasSubLink((Node *) rte->securityQuals);
6570 495 [ + + ]: 40 : if (sub_action->hasSubLinks)
6310 bruce@momjian.us 496 : 4 : break; /* no need to keep scanning rtable */
497 : : }
498 : : }
499 : :
500 : : /*
501 : : * Also, we might have absorbed some RTEs with RLS conditions into the
502 : : * sub_action. If so, mark it as hasRowSecurity, whether or not those
503 : : * RTEs will be referenced after we finish rewriting. (Note: currently
504 : : * this is a no-op because RLS conditions aren't added till later, but it
505 : : * seems like good future-proofing to do this anyway.)
506 : : */
3601 tgl@sss.pgh.pa.us 507 : 976 : sub_action->hasRowSecurity |= parsetree->hasRowSecurity;
508 : :
509 : : /*
510 : : * Each rule action's jointree should be the main parsetree's jointree
511 : : * plus that rule's jointree, but usually *without* the original rtindex
512 : : * that we're replacing (if present, which it won't be for INSERT). Note
513 : : * that if the rule action refers to OLD, its jointree will add a
514 : : * reference to rt_index. If the rule action doesn't refer to OLD, but
515 : : * either the rule_qual or the user query quals do, then we need to keep
516 : : * the original rtindex in the jointree to provide data for the quals. We
517 : : * don't want the original rtindex to be joined twice, however, so avoid
518 : : * keeping it if the rule action mentions it.
519 : : *
520 : : * As above, the action's jointree must not share substructure with the
521 : : * main parsetree's.
522 : : */
8467 523 [ + + ]: 976 : if (sub_action->commandType != CMD_UTILITY)
524 : : {
525 : : bool keeporig;
526 : : List *newjointree;
527 : :
528 [ - + ]: 956 : Assert(sub_action->jointree != NULL);
9313 bruce@momjian.us 529 : 956 : keeporig = (!rangeTableEntry_used((Node *) sub_action->jointree,
530 [ + + + - ]: 2220 : rt_index, 0)) &&
9230 tgl@sss.pgh.pa.us 531 [ - + ]: 1264 : (rangeTableEntry_used(rule_qual, rt_index, 0) ||
7645 bruce@momjian.us 532 : 632 : rangeTableEntry_used(parsetree->jointree->quals, rt_index, 0));
9367 tgl@sss.pgh.pa.us 533 : 956 : newjointree = adjustJoinTreeList(parsetree, !keeporig, rt_index);
8467 534 [ + + ]: 956 : if (newjointree != NIL)
535 : : {
536 : : /*
537 : : * If sub_action is a setop, manipulating its jointree will do no
538 : : * good at all, because the jointree is dummy. (Perhaps someday
539 : : * we could push the joining and quals down to the member
540 : : * statements of the setop?)
541 : : */
542 [ - + ]: 184 : if (sub_action->setOperations != NULL)
8458 tgl@sss.pgh.pa.us 543 [ # # ]:UBC 0 : ereport(ERROR,
544 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
545 : : errmsg("conditional UNION/INTERSECT/EXCEPT statements are not implemented")));
546 : :
8467 tgl@sss.pgh.pa.us 547 :CBC 368 : sub_action->jointree->fromlist =
8148 neilc@samurai.com 548 : 184 : list_concat(newjointree, sub_action->jointree->fromlist);
549 : :
550 : : /*
551 : : * There could have been some SubLinks in newjointree, in which
552 : : * case we'd better mark the sub_action correctly.
553 : : */
7606 tgl@sss.pgh.pa.us 554 [ + + + - ]: 184 : if (parsetree->hasSubLinks && !sub_action->hasSubLinks)
555 : 4 : sub_action->hasSubLinks =
556 : 4 : checkExprHasSubLink((Node *) newjointree);
557 : : }
558 : : }
559 : :
560 : : /*
561 : : * If the original query has any CTEs, copy them into the rule action. But
562 : : * we don't need them for a utility action.
563 : : */
5584 564 [ + + + - ]: 976 : if (parsetree->cteList != NIL && sub_action->commandType != CMD_UTILITY)
565 : : {
566 : : /*
567 : : * Annoying implementation restriction: because CTEs are identified by
568 : : * name within a cteList, we can't merge a CTE from the original query
569 : : * if it has the same name as any CTE in the rule action.
570 : : *
571 : : * This could possibly be fixed by using some sort of internally
572 : : * generated ID, instead of names, to link CTE RTEs to their CTEs.
573 : : * However, decompiling the results would be quite confusing; note the
574 : : * merge of hasRecursive flags below, which could change the apparent
575 : : * semantics of such redundantly-named CTEs.
576 : : */
577 [ + - + + : 48 : foreach(lc, parsetree->cteList)
+ + ]
578 : : {
579 : 24 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
580 : : ListCell *lc2;
581 : :
582 [ + + + + : 28 : foreach(lc2, sub_action->cteList)
+ + ]
583 : : {
584 : 4 : CommonTableExpr *cte2 = (CommonTableExpr *) lfirst(lc2);
585 : :
586 [ - + ]: 4 : if (strcmp(cte->ctename, cte2->ctename) == 0)
5584 tgl@sss.pgh.pa.us 587 [ # # ]:UBC 0 : ereport(ERROR,
588 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
589 : : errmsg("WITH query name \"%s\" appears in both a rule action and the query being rewritten",
590 : : cte->ctename)));
591 : : }
592 : : }
593 : :
594 : : /*
595 : : * OK, it's safe to combine the CTE lists. Beware that RewriteQuery
596 : : * knows we concatenate the lists in this order.
597 : : */
5584 tgl@sss.pgh.pa.us 598 :CBC 24 : sub_action->cteList = list_concat(sub_action->cteList,
599 : 24 : copyObject(parsetree->cteList));
600 : : /* ... and don't forget about the associated flags */
1838 601 : 24 : sub_action->hasRecursive |= parsetree->hasRecursive;
602 : 24 : sub_action->hasModifyingCTE |= parsetree->hasModifyingCTE;
603 : :
604 : : /*
605 : : * If rule_action is different from sub_action (i.e., the rule action
606 : : * is an INSERT...SELECT), then we might have just added some
607 : : * data-modifying CTEs that are not at the top query level. This is
608 : : * disallowed by the parser and we mustn't generate such trees here
609 : : * either, so throw an error.
610 : : *
611 : : * Conceivably such cases could be supported by attaching the original
612 : : * query's CTEs to rule_action not sub_action. But to do that, we'd
613 : : * have to increment ctelevelsup in RTEs and SubLinks copied from the
614 : : * original query. For now, it doesn't seem worth the trouble.
615 : : */
616 [ + + + + ]: 24 : if (sub_action->hasModifyingCTE && rule_action != sub_action)
617 [ + - ]: 4 : ereport(ERROR,
618 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
619 : : errmsg("INSERT ... SELECT rule actions are not supported for queries having data-modifying statements in WITH")));
620 : : }
621 : :
622 : : /*
623 : : * Event Qualification forces copying of parsetree and splitting into two
624 : : * queries one w/rule_qual, one w/NOT rule_qual. Also add user query qual
625 : : * onto rule action
626 : : */
9230 627 : 972 : AddQual(sub_action, rule_qual);
628 : :
9420 629 : 972 : AddQual(sub_action, parsetree->jointree->quals);
630 : :
631 : : /*
632 : : * Rewrite new.attribute with right hand side of target-list entry for
633 : : * appropriate field name in insert/update.
634 : : *
635 : : * KLUGE ALERT: since ReplaceVarsFromTargetList returns a mutated copy, we
636 : : * can't just apply it to sub_action; we have to remember to update the
637 : : * sublink inside rule_action, too.
638 : : */
8079 639 [ + + + + ]: 972 : if ((event == CMD_INSERT || event == CMD_UPDATE) &&
640 [ + + ]: 844 : sub_action->commandType != CMD_UTILITY)
641 : : {
152 rguo@postgresql.org 642 : 824 : RangeTblEntry *new_rte = rt_fetch(new_varno, sub_action->rtable);
643 : : Relation new_rel;
644 : : List *gen_cols;
645 : :
646 : : /*
647 : : * The target list does not contain entries for generated columns
648 : : * (they are removed by rewriteTargetListIU), so we must build entries
649 : : * for them here, so that new.gen_col can be rewritten correctly.
650 : : */
651 : 824 : new_rel = relation_open(new_rte->relid, NoLock);
652 : 824 : gen_cols = get_generated_columns(new_rel, new_varno, true);
653 : 824 : relation_close(new_rel, NoLock);
654 : :
655 : : /*
656 : : * The generated column expressions refer to new.attribute, so they
657 : : * must be rewritten before they can be used as replacements.
658 : : */
659 : : gen_cols = (List *)
660 [ + + ]: 824 : ReplaceVarsFromTargetList((Node *) gen_cols,
661 : : new_varno,
662 : : 0,
663 : : new_rte,
664 : : parsetree->targetList,
665 : : sub_action->resultRelation,
666 : : (event == CMD_UPDATE) ?
667 : : REPLACEVARS_CHANGE_VARNO :
668 : : REPLACEVARS_SUBSTITUTE_NULL,
669 : : current_varno,
670 : : &sub_action->hasSubLinks);
671 : :
672 : : /*
673 : : * Now rewrite new.attribute in sub_action, using both the target list
674 : : * and the rewritten generated column expressions.
675 : : */
676 : : sub_action = (Query *)
5064 tgl@sss.pgh.pa.us 677 [ + + ]: 1648 : ReplaceVarsFromTargetList((Node *) sub_action,
678 : : new_varno,
679 : : 0,
680 : : new_rte,
152 rguo@postgresql.org 681 : 824 : list_concat(gen_cols, parsetree->targetList),
682 : : sub_action->resultRelation,
683 : : (event == CMD_UPDATE) ?
684 : : REPLACEVARS_CHANGE_VARNO :
685 : : REPLACEVARS_SUBSTITUTE_NULL,
686 : : current_varno,
687 : : NULL);
9420 tgl@sss.pgh.pa.us 688 [ + + ]: 824 : if (sub_action_ptr)
689 : 36 : *sub_action_ptr = sub_action;
690 : : else
9230 691 : 788 : rule_action = sub_action;
692 : : }
693 : :
694 : : /*
695 : : * If rule_action is INSERT .. ON CONFLICT DO SELECT, the parser should
696 : : * have verified that it has a RETURNING clause, but we must also check
697 : : * that the triggering query has a RETURNING clause.
698 : : */
220 dean.a.rasheed@gmail 699 [ + + ]: 972 : if (rule_action->onConflict &&
700 [ + + ]: 52 : rule_action->onConflict->action == ONCONFLICT_SELECT &&
701 [ + - + + ]: 20 : (!rule_action->returningList || !parsetree->returningList))
702 [ + - ]: 4 : ereport(ERROR,
703 : : errcode(ERRCODE_SYNTAX_ERROR),
704 : : errmsg("ON CONFLICT DO SELECT requires a RETURNING clause"),
705 : : errdetail("A rule action is INSERT ... ON CONFLICT DO SELECT, which requires a RETURNING clause."));
706 : :
707 : : /*
708 : : * If rule_action has a RETURNING clause, then either throw it away if the
709 : : * triggering query has no RETURNING clause, or rewrite it to emit what
710 : : * the triggering query's RETURNING clause asks for. Throw an error if
711 : : * more than one rule has a RETURNING clause.
712 : : */
7323 tgl@sss.pgh.pa.us 713 [ + + ]: 968 : if (!parsetree->returningList)
714 : 836 : rule_action->returningList = NIL;
715 [ + + ]: 132 : else if (rule_action->returningList)
716 : : {
717 [ - + ]: 124 : if (*returning_flag)
7323 tgl@sss.pgh.pa.us 718 [ # # ]:UBC 0 : ereport(ERROR,
719 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
720 : : errmsg("cannot have RETURNING lists in multiple rules")));
7323 tgl@sss.pgh.pa.us 721 :CBC 124 : *returning_flag = true;
722 : 112 : rule_action->returningList = (List *)
5064 723 : 124 : ReplaceVarsFromTargetList((Node *) parsetree->returningList,
724 : : parsetree->resultRelation,
725 : : 0,
726 : 124 : rt_fetch(parsetree->resultRelation,
727 : : parsetree->rtable),
728 : : rule_action->returningList,
729 : : rule_action->resultRelation,
730 : : REPLACEVARS_REPORT_ERROR,
731 : : 0,
732 : : &rule_action->hasSubLinks);
733 : :
734 : : /* use triggering query's aliases for OLD and NEW in RETURNING list */
612 dean.a.rasheed@gmail 735 : 112 : rule_action->returningOldAlias = parsetree->returningOldAlias;
736 : 112 : rule_action->returningNewAlias = parsetree->returningNewAlias;
737 : :
738 : : /*
739 : : * There could have been some SubLinks in parsetree's returningList,
740 : : * in which case we'd better mark the rule_action correctly.
741 : : */
6570 tgl@sss.pgh.pa.us 742 [ - + - - ]: 112 : if (parsetree->hasSubLinks && !rule_action->hasSubLinks)
6570 tgl@sss.pgh.pa.us 743 :UBC 0 : rule_action->hasSubLinks =
6310 bruce@momjian.us 744 : 0 : checkExprHasSubLink((Node *) rule_action->returningList);
745 : : }
746 : :
9230 tgl@sss.pgh.pa.us 747 :CBC 956 : return rule_action;
748 : : }
749 : :
750 : : /*
751 : : * Copy the query's jointree list, and optionally attempt to remove any
752 : : * occurrence of the given rt_index as a top-level join item (we do not look
753 : : * for it within join items; this is OK because we are only expecting to find
754 : : * it as an UPDATE or DELETE target relation, which will be at the top level
755 : : * of the join). Returns modified jointree list --- this is a separate copy
756 : : * sharing no nodes with the original.
757 : : */
758 : : static List *
9367 759 : 956 : adjustJoinTreeList(Query *parsetree, bool removert, int rt_index)
760 : : {
9231 761 : 956 : List *newjointree = copyObject(parsetree->jointree->fromlist);
762 : : ListCell *l;
763 : :
9367 764 [ + - ]: 956 : if (removert)
765 : : {
8152 neilc@samurai.com 766 [ + + + + : 1116 : foreach(l, newjointree)
+ + ]
767 : : {
768 : 520 : RangeTblRef *rtr = lfirst(l);
769 : :
8678 tgl@sss.pgh.pa.us 770 [ + - ]: 520 : if (IsA(rtr, RangeTblRef) &&
771 [ + + ]: 520 : rtr->rtindex == rt_index)
772 : : {
2159 drowley@postgresql.o 773 : 360 : newjointree = foreach_delete_current(newjointree, l);
9367 tgl@sss.pgh.pa.us 774 : 360 : break;
775 : : }
776 : : }
777 : : }
9504 778 : 956 : return newjointree;
779 : : }
780 : :
781 : :
782 : : /*
783 : : * rewriteTargetListIU - rewrite INSERT/UPDATE targetlist into standard form
784 : : *
785 : : * This has the following responsibilities:
786 : : *
787 : : * 1. For an INSERT, add tlist entries to compute default values for any
788 : : * attributes that have defaults and are not assigned to in the given tlist.
789 : : * (We do not insert anything for default-less attributes, however. The
790 : : * planner will later insert NULLs for them, but there's no reason to slow
791 : : * down rewriter processing with extra tlist nodes.) Also, for both INSERT
792 : : * and UPDATE, replace explicit DEFAULT specifications with column default
793 : : * expressions.
794 : : *
795 : : * 2. Merge multiple entries for the same target attribute, or declare error
796 : : * if we can't. Multiple entries are only allowed for INSERT/UPDATE of
797 : : * portions of an array or record field, for example
798 : : * UPDATE table SET foo[2] = 42, foo[4] = 43;
799 : : * We can merge such operations into a single assignment op. Essentially,
800 : : * the expression we want to produce in this case is like
801 : : * foo = array_set_element(array_set_element(foo, 2, 42), 4, 43)
802 : : *
803 : : * 3. Sort the tlist into standard order: non-junk fields in order by resno,
804 : : * then junk fields (these in no particular order).
805 : : *
806 : : * We must do items 1 and 2 before firing rewrite rules, else rewritten
807 : : * references to NEW.foo will produce wrong or incomplete results. Item 3
808 : : * is not needed for rewriting, but it is helpful for the planner, and we
809 : : * can do it essentially for free while handling the other items.
810 : : *
811 : : * If values_rte is non-NULL (i.e., we are doing a multi-row INSERT using
812 : : * values from a VALUES RTE), we populate *unused_values_attrnos with the
813 : : * attribute numbers of any unused columns from the VALUES RTE. This can
814 : : * happen for identity and generated columns whose targetlist entries are
815 : : * replaced with generated expressions (if INSERT ... OVERRIDING USER VALUE is
816 : : * used, or all the values to be inserted are DEFAULT). This information is
817 : : * required by rewriteValuesRTE() to handle any DEFAULT items in the unused
818 : : * columns. The caller must have initialized *unused_values_attrnos to NULL.
819 : : */
820 : : static List *
4153 andres@anarazel.de 821 : 56437 : rewriteTargetListIU(List *targetList,
822 : : CmdType commandType,
823 : : OverridingKind override,
824 : : Relation target_relation,
825 : : RangeTblEntry *values_rte,
826 : : int values_rte_index,
827 : : Bitmapset **unused_values_attrnos)
828 : : {
829 : : TargetEntry **new_tles;
8934 tgl@sss.pgh.pa.us 830 : 56437 : List *new_tlist = NIL;
7848 831 : 56437 : List *junk_tlist = NIL;
832 : : Form_pg_attribute att_tup;
833 : : int attrno,
834 : : next_junk_attrno,
835 : : numattrs;
836 : : ListCell *temp;
2128 837 : 56437 : Bitmapset *default_only_cols = NULL;
838 : :
839 : : /*
840 : : * We process the normal (non-junk) attributes by scanning the input tlist
841 : : * once and transferring TLEs into an array, then scanning the array to
842 : : * build an output tlist. This avoids O(N^2) behavior for large numbers
843 : : * of attributes.
844 : : *
845 : : * Junk attributes are tossed into a separate list during the same tlist
846 : : * scan, then appended to the reconstructed tlist.
847 : : */
8934 848 : 56437 : numattrs = RelationGetNumberOfAttributes(target_relation);
34 michael@paquier.xyz 849 :GNC 56437 : new_tles = palloc0_array(TargetEntry *, numattrs);
7848 tgl@sss.pgh.pa.us 850 :CBC 56437 : next_junk_attrno = numattrs + 1;
851 : :
4153 andres@anarazel.de 852 [ + + + + : 158341 : foreach(temp, targetList)
+ + ]
853 : : {
7848 tgl@sss.pgh.pa.us 854 : 101916 : TargetEntry *old_tle = (TargetEntry *) lfirst(temp);
855 : :
7837 856 [ + + ]: 101916 : if (!old_tle->resjunk)
857 : : {
858 : : /* Normal attr: stash it into new_tles[] */
859 : 101829 : attrno = old_tle->resno;
7848 860 [ + - - + ]: 101829 : if (attrno < 1 || attrno > numattrs)
7848 tgl@sss.pgh.pa.us 861 [ # # ]:UBC 0 : elog(ERROR, "bogus resno %d in targetlist", attrno);
3318 andres@anarazel.de 862 :CBC 101829 : att_tup = TupleDescAttr(target_relation->rd_att, attrno - 1);
863 : :
864 : : /* We can (and must) ignore deleted attributes */
7848 tgl@sss.pgh.pa.us 865 [ - + ]: 101829 : if (att_tup->attisdropped)
7848 tgl@sss.pgh.pa.us 866 :UBC 0 : continue;
867 : :
868 : : /* Merge with any prior assignment to same attribute */
7848 tgl@sss.pgh.pa.us 869 :CBC 101817 : new_tles[attrno - 1] =
870 : 101829 : process_matched_tle(old_tle,
871 : 101829 : new_tles[attrno - 1],
872 : 101829 : NameStr(att_tup->attname));
873 : : }
874 : : else
875 : : {
876 : : /*
877 : : * Copy all resjunk tlist entries to junk_tlist, and assign them
878 : : * resnos above the last real resno.
879 : : *
880 : : * Typical junk entries include ORDER BY or GROUP BY expressions
881 : : * (are these actually possible in an INSERT or UPDATE?), system
882 : : * attribute references, etc.
883 : : */
884 : :
885 : : /* Get the resno right, but don't copy unnecessarily */
7837 886 [ - + ]: 87 : if (old_tle->resno != next_junk_attrno)
887 : : {
7837 tgl@sss.pgh.pa.us 888 :UBC 0 : old_tle = flatCopyTargetEntry(old_tle);
889 : 0 : old_tle->resno = next_junk_attrno;
890 : : }
7848 tgl@sss.pgh.pa.us 891 :CBC 87 : junk_tlist = lappend(junk_tlist, old_tle);
892 : 87 : next_junk_attrno++;
893 : : }
894 : : }
895 : :
896 [ + + ]: 242808 : for (attrno = 1; attrno <= numattrs; attrno++)
897 : : {
898 : 186515 : TargetEntry *new_tle = new_tles[attrno - 1];
899 : : bool apply_default;
900 : :
3318 andres@anarazel.de 901 : 186515 : att_tup = TupleDescAttr(target_relation->rd_att, attrno - 1);
902 : :
903 : : /* We can (and must) ignore deleted attributes */
7848 tgl@sss.pgh.pa.us 904 [ + + ]: 186515 : if (att_tup->attisdropped)
905 : 673 : continue;
906 : :
907 : : /*
908 : : * Handle the two cases where we need to insert a default expression:
909 : : * it's an INSERT and there's no tlist entry for the column, or the
910 : : * tlist entry is a DEFAULT placeholder node.
911 : : */
3454 peter_e@gmx.net 912 [ + + + + : 287398 : apply_default = ((new_tle == NULL && commandType == CMD_INSERT) ||
+ + ]
3378 tgl@sss.pgh.pa.us 913 [ + - + + ]: 101556 : (new_tle && new_tle->expr && IsA(new_tle->expr, SetToDefault)));
914 : :
3454 peter_e@gmx.net 915 [ + + ]: 185842 : if (commandType == CMD_INSERT)
916 : : {
2128 tgl@sss.pgh.pa.us 917 : 102925 : int values_attrno = 0;
918 : :
919 : : /* Source attribute number for values that come from a VALUES RTE */
920 [ + + + + : 102925 : if (values_rte && new_tle && IsA(new_tle->expr, Var))
+ + ]
921 : : {
922 : 5820 : Var *var = (Var *) new_tle->expr;
923 : :
924 [ + - ]: 5820 : if (var->varno == values_rte_index)
925 : 5820 : values_attrno = var->varattno;
926 : : }
927 : :
928 : : /*
929 : : * Can only insert DEFAULT into GENERATED ALWAYS identity columns,
930 : : * unless either OVERRIDING USER VALUE or OVERRIDING SYSTEM VALUE
931 : : * is specified.
932 : : */
3454 peter_e@gmx.net 933 [ + + + + ]: 102925 : if (att_tup->attidentity == ATTRIBUTE_IDENTITY_ALWAYS && !apply_default)
934 : : {
2364 peter@eisentraut.org 935 [ + + ]: 94 : if (override == OVERRIDING_USER_VALUE)
936 : 28 : apply_default = true;
937 [ + + ]: 66 : else if (override != OVERRIDING_SYSTEM_VALUE)
938 : : {
939 : : /*
940 : : * If this column's values come from a VALUES RTE, test
941 : : * whether it contains only SetToDefault items. Since the
942 : : * VALUES list might be quite large, we arrange to only
943 : : * scan it once.
944 : : */
2128 tgl@sss.pgh.pa.us 945 [ + + ]: 34 : if (values_attrno != 0)
946 : : {
947 [ + - ]: 18 : if (default_only_cols == NULL)
948 : 18 : default_only_cols = findDefaultOnlyColumns(values_rte);
949 : :
950 [ + + ]: 18 : if (bms_is_member(values_attrno, default_only_cols))
951 : 6 : apply_default = true;
952 : : }
953 : :
954 [ + + ]: 34 : if (!apply_default)
955 [ + - ]: 28 : ereport(ERROR,
956 : : (errcode(ERRCODE_GENERATED_ALWAYS),
957 : : errmsg("cannot insert a non-DEFAULT value into column \"%s\"",
958 : : NameStr(att_tup->attname)),
959 : : errdetail("Column \"%s\" is an identity column defined as GENERATED ALWAYS.",
960 : : NameStr(att_tup->attname)),
961 : : errhint("Use OVERRIDING SYSTEM VALUE to override.")));
962 : : }
963 : : }
964 : :
965 : : /*
966 : : * Although inserting into a GENERATED BY DEFAULT identity column
967 : : * is allowed, apply the default if OVERRIDING USER VALUE is
968 : : * specified.
969 : : */
970 [ + + + + ]: 102897 : if (att_tup->attidentity == ATTRIBUTE_IDENTITY_BY_DEFAULT &&
971 : : override == OVERRIDING_USER_VALUE)
3454 peter_e@gmx.net 972 : 12 : apply_default = true;
973 : :
974 : : /*
975 : : * Can only insert DEFAULT into generated columns. (The
976 : : * OVERRIDING clause does not apply to generated columns, so we
977 : : * don't consider it here.)
978 : : */
2731 peter@eisentraut.org 979 [ + + + + ]: 102897 : if (att_tup->attgenerated && !apply_default)
980 : : {
981 : : /*
982 : : * If this column's values come from a VALUES RTE, test
983 : : * whether it contains only SetToDefault items, as above.
984 : : */
2128 tgl@sss.pgh.pa.us 985 [ + + ]: 117 : if (values_attrno != 0)
986 : : {
987 [ + - ]: 81 : if (default_only_cols == NULL)
988 : 81 : default_only_cols = findDefaultOnlyColumns(values_rte);
989 : :
990 [ + + ]: 81 : if (bms_is_member(values_attrno, default_only_cols))
991 : 25 : apply_default = true;
992 : : }
993 : :
994 [ + + ]: 117 : if (!apply_default)
995 [ + - ]: 92 : ereport(ERROR,
996 : : (errcode(ERRCODE_GENERATED_ALWAYS),
997 : : errmsg("cannot insert a non-DEFAULT value into column \"%s\"",
998 : : NameStr(att_tup->attname)),
999 : : errdetail("Column \"%s\" is a generated column.",
1000 : : NameStr(att_tup->attname))));
1001 : : }
1002 : :
1003 : : /*
1004 : : * For an INSERT from a VALUES RTE, return the attribute numbers
1005 : : * of any VALUES columns that will no longer be used (due to the
1006 : : * targetlist entry being replaced by a default expression).
1007 : : */
1008 [ + + + + : 102805 : if (values_attrno != 0 && apply_default && unused_values_attrnos)
+ - ]
1009 : 47 : *unused_values_attrnos = bms_add_member(*unused_values_attrnos,
1010 : : values_attrno);
1011 : : }
1012 : :
1013 : : /*
1014 : : * Updates to identity and generated columns follow the same rules as
1015 : : * above, except that UPDATE doesn't admit OVERRIDING clauses. Also,
1016 : : * the source can't be a VALUES RTE, so we needn't consider that.
1017 : : */
3454 peter_e@gmx.net 1018 [ + + ]: 185722 : if (commandType == CMD_UPDATE)
1019 : : {
2127 tgl@sss.pgh.pa.us 1020 [ + + + - ]: 82917 : if (att_tup->attidentity == ATTRIBUTE_IDENTITY_ALWAYS &&
1021 [ + + ]: 8 : new_tle && !apply_default)
3454 peter_e@gmx.net 1022 [ + - ]: 4 : ereport(ERROR,
1023 : : (errcode(ERRCODE_GENERATED_ALWAYS),
1024 : : errmsg("column \"%s\" can only be updated to DEFAULT",
1025 : : NameStr(att_tup->attname)),
1026 : : errdetail("Column \"%s\" is an identity column defined as GENERATED ALWAYS.",
1027 : : NameStr(att_tup->attname))));
1028 : :
2731 peter@eisentraut.org 1029 [ + + + + : 82913 : if (att_tup->attgenerated && new_tle && !apply_default)
+ + ]
1030 [ + - ]: 8 : ereport(ERROR,
1031 : : (errcode(ERRCODE_GENERATED_ALWAYS),
1032 : : errmsg("column \"%s\" can only be updated to DEFAULT",
1033 : : NameStr(att_tup->attname)),
1034 : : errdetail("Column \"%s\" is a generated column.",
1035 : : NameStr(att_tup->attname))));
1036 : : }
1037 : :
1038 [ + + ]: 185710 : if (att_tup->attgenerated)
1039 : : {
1040 : : /*
1041 : : * virtual generated column stores a null value; stored generated
1042 : : * column will be fixed in executor
1043 : : */
1044 : 1170 : new_tle = NULL;
1045 : : }
1046 [ + + ]: 184540 : else if (apply_default)
1047 : : {
1048 : : Node *new_expr;
1049 : :
3152 peter_e@gmx.net 1050 : 15339 : new_expr = build_column_default(target_relation, attrno);
1051 : :
1052 : : /*
1053 : : * If there is no default (ie, default is effectively NULL), we
1054 : : * can omit the tlist entry in the INSERT case, since the planner
1055 : : * can insert a NULL for itself, and there's no point in spending
1056 : : * any more rewriter cycles on the entry. But in the UPDATE case
1057 : : * we've got to explicitly set the column to NULL.
1058 : : */
8480 tgl@sss.pgh.pa.us 1059 [ + + ]: 15339 : if (!new_expr)
1060 : : {
1061 [ + + ]: 11688 : if (commandType == CMD_INSERT)
1062 : 11675 : new_tle = NULL;
1063 : : else
599 1064 : 13 : new_expr = coerce_null_to_domain(att_tup->atttypid,
1065 : : att_tup->atttypmod,
1066 : : att_tup->attcollation,
1067 : 13 : att_tup->attlen,
1068 : 13 : att_tup->attbyval);
1069 : : }
1070 : :
8934 1071 [ + + ]: 15339 : if (new_expr)
7837 1072 : 3664 : new_tle = makeTargetEntry((Expr *) new_expr,
1073 : : attrno,
1074 : 3664 : pstrdup(NameStr(att_tup->attname)),
1075 : : false);
1076 : : }
1077 : :
8934 1078 [ + + ]: 185710 : if (new_tle)
1079 : 104587 : new_tlist = lappend(new_tlist, new_tle);
1080 : : }
1081 : :
7848 1082 : 56293 : pfree(new_tles);
1083 : :
4153 andres@anarazel.de 1084 : 56293 : return list_concat(new_tlist, junk_tlist);
1085 : : }
1086 : :
1087 : :
1088 : : /*
1089 : : * Convert a matched TLE from the original tlist into a correct new TLE.
1090 : : *
1091 : : * This routine detects and handles multiple assignments to the same target
1092 : : * attribute. (The attribute name is needed only for error messages.)
1093 : : */
1094 : : static TargetEntry *
8934 tgl@sss.pgh.pa.us 1095 : 101829 : process_matched_tle(TargetEntry *src_tle,
1096 : : TargetEntry *prior_tle,
1097 : : const char *attrName)
1098 : : {
1099 : : TargetEntry *result;
3358 1100 : 101829 : CoerceToDomain *coerce_expr = NULL;
1101 : : Node *src_expr;
1102 : : Node *prior_expr;
1103 : : Node *src_input;
1104 : : Node *prior_input;
1105 : : Node *priorbottom;
1106 : : Node *newexpr;
1107 : :
8934 1108 [ + + ]: 101829 : if (prior_tle == NULL)
1109 : : {
1110 : : /*
1111 : : * Normal case where this is the first assignment to the attribute.
1112 : : */
1113 : 101604 : return src_tle;
1114 : : }
1115 : :
1116 : : /*----------
1117 : : * Multiple assignments to same attribute. Allow only if all are
1118 : : * FieldStore or SubscriptingRef assignment operations. This is a bit
1119 : : * tricky because what we may actually be looking at is a nest of
1120 : : * such nodes; consider
1121 : : * UPDATE tab SET col.fld1.subfld1 = x, col.fld2.subfld2 = y
1122 : : * The two expressions produced by the parser will look like
1123 : : * FieldStore(col, fld1, FieldStore(placeholder, subfld1, x))
1124 : : * FieldStore(col, fld2, FieldStore(placeholder, subfld2, y))
1125 : : * However, we can ignore the substructure and just consider the top
1126 : : * FieldStore or SubscriptingRef from each assignment, because it works to
1127 : : * combine these as
1128 : : * FieldStore(FieldStore(col, fld1,
1129 : : * FieldStore(placeholder, subfld1, x)),
1130 : : * fld2, FieldStore(placeholder, subfld2, y))
1131 : : * Note the leftmost expression goes on the inside so that the
1132 : : * assignments appear to occur left-to-right.
1133 : : *
1134 : : * For FieldStore, instead of nesting we can generate a single
1135 : : * FieldStore with multiple target fields. We must nest when
1136 : : * SubscriptingRefs are involved though.
1137 : : *
1138 : : * As a further complication, the destination column might be a domain,
1139 : : * resulting in each assignment containing a CoerceToDomain node over a
1140 : : * FieldStore or SubscriptingRef. These should have matching target
1141 : : * domains, so we strip them and reconstitute a single CoerceToDomain over
1142 : : * the combined FieldStore/SubscriptingRef nodes. (Notice that this has
1143 : : * the result that the domain's checks are applied only after we do all
1144 : : * the field or element updates, not after each one. This is desirable.)
1145 : : *----------
1146 : : */
8138 1147 : 225 : src_expr = (Node *) src_tle->expr;
1148 : 225 : prior_expr = (Node *) prior_tle->expr;
1149 : :
3358 1150 [ + - + + : 225 : if (src_expr && IsA(src_expr, CoerceToDomain) &&
+ - ]
1151 [ + - ]: 108 : prior_expr && IsA(prior_expr, CoerceToDomain) &&
1152 : 108 : ((CoerceToDomain *) src_expr)->resulttype ==
1153 [ + - ]: 108 : ((CoerceToDomain *) prior_expr)->resulttype)
1154 : : {
1155 : : /* we assume without checking that resulttypmod/resultcollid match */
1156 : 108 : coerce_expr = (CoerceToDomain *) src_expr;
1157 : 108 : src_expr = (Node *) ((CoerceToDomain *) src_expr)->arg;
1158 : 108 : prior_expr = (Node *) ((CoerceToDomain *) prior_expr)->arg;
1159 : : }
1160 : :
8138 1161 : 225 : src_input = get_assignment_input(src_expr);
1162 : 225 : prior_input = get_assignment_input(prior_expr);
1163 [ + + + - ]: 225 : if (src_input == NULL ||
1164 [ - + ]: 213 : prior_input == NULL ||
1165 : 213 : exprType(src_expr) != exprType(prior_expr))
8458 1166 [ + - ]: 12 : ereport(ERROR,
1167 : : (errcode(ERRCODE_SYNTAX_ERROR),
1168 : : errmsg("multiple assignments to same column \"%s\"",
1169 : : attrName)));
1170 : :
1171 : : /*
1172 : : * Prior TLE could be a nest of assignments if we do this more than once.
1173 : : */
8138 1174 : 213 : priorbottom = prior_input;
1175 : : for (;;)
1176 : 28 : {
8057 bruce@momjian.us 1177 : 241 : Node *newbottom = get_assignment_input(priorbottom);
1178 : :
8138 tgl@sss.pgh.pa.us 1179 [ + + ]: 241 : if (newbottom == NULL)
1180 : 213 : break; /* found the original Var reference */
1181 : 28 : priorbottom = newbottom;
1182 : : }
1183 [ - + ]: 213 : if (!equal(priorbottom, src_input))
8458 tgl@sss.pgh.pa.us 1184 [ # # ]:UBC 0 : ereport(ERROR,
1185 : : (errcode(ERRCODE_SYNTAX_ERROR),
1186 : : errmsg("multiple assignments to same column \"%s\"",
1187 : : attrName)));
1188 : :
1189 : : /*
1190 : : * Looks OK to nest 'em.
1191 : : */
8138 tgl@sss.pgh.pa.us 1192 [ + + ]:CBC 213 : if (IsA(src_expr, FieldStore))
1193 : : {
8057 bruce@momjian.us 1194 : 84 : FieldStore *fstore = makeNode(FieldStore);
1195 : :
8138 tgl@sss.pgh.pa.us 1196 [ + - ]: 84 : if (IsA(prior_expr, FieldStore))
1197 : : {
1198 : : /* combine the two */
1199 : 84 : memcpy(fstore, prior_expr, sizeof(FieldStore));
1200 : 84 : fstore->newvals =
2596 1201 : 84 : list_concat_copy(((FieldStore *) prior_expr)->newvals,
1202 : 84 : ((FieldStore *) src_expr)->newvals);
8138 1203 : 84 : fstore->fieldnums =
2596 1204 : 84 : list_concat_copy(((FieldStore *) prior_expr)->fieldnums,
1205 : 84 : ((FieldStore *) src_expr)->fieldnums);
1206 : : }
1207 : : else
1208 : : {
1209 : : /* general case, just nest 'em */
8138 tgl@sss.pgh.pa.us 1210 :UBC 0 : memcpy(fstore, src_expr, sizeof(FieldStore));
1211 : 0 : fstore->arg = (Expr *) prior_expr;
1212 : : }
8138 tgl@sss.pgh.pa.us 1213 :CBC 84 : newexpr = (Node *) fstore;
1214 : : }
2788 alvherre@alvh.no-ip. 1215 [ + - ]: 129 : else if (IsA(src_expr, SubscriptingRef))
1216 : : {
1217 : 129 : SubscriptingRef *sbsref = makeNode(SubscriptingRef);
1218 : :
1219 : 129 : memcpy(sbsref, src_expr, sizeof(SubscriptingRef));
1220 : 129 : sbsref->refexpr = (Expr *) prior_expr;
1221 : 129 : newexpr = (Node *) sbsref;
1222 : : }
1223 : : else
1224 : : {
7171 bruce@momjian.us 1225 [ # # ]:UBC 0 : elog(ERROR, "cannot happen");
1226 : : newexpr = NULL;
1227 : : }
1228 : :
3358 tgl@sss.pgh.pa.us 1229 [ + + ]:CBC 213 : if (coerce_expr)
1230 : : {
1231 : : /* put back the CoerceToDomain */
1232 : 108 : CoerceToDomain *newcoerce = makeNode(CoerceToDomain);
1233 : :
1234 : 108 : memcpy(newcoerce, coerce_expr, sizeof(CoerceToDomain));
1235 : 108 : newcoerce->arg = (Expr *) newexpr;
1236 : 108 : newexpr = (Node *) newcoerce;
1237 : : }
1238 : :
7837 1239 : 213 : result = flatCopyTargetEntry(src_tle);
1240 : 213 : result->expr = (Expr *) newexpr;
1241 : 213 : return result;
1242 : : }
1243 : :
1244 : : /*
1245 : : * If node is an assignment node, return its input; else return NULL
1246 : : */
1247 : : static Node *
8138 1248 : 691 : get_assignment_input(Node *node)
1249 : : {
1250 [ - + ]: 691 : if (node == NULL)
8138 tgl@sss.pgh.pa.us 1251 :UBC 0 : return NULL;
8138 tgl@sss.pgh.pa.us 1252 [ + + ]:CBC 691 : if (IsA(node, FieldStore))
1253 : : {
1254 : 168 : FieldStore *fstore = (FieldStore *) node;
1255 : :
1256 : 168 : return (Node *) fstore->arg;
1257 : : }
2788 alvherre@alvh.no-ip. 1258 [ + + ]: 523 : else if (IsA(node, SubscriptingRef))
1259 : : {
1260 : 286 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1261 : :
1262 [ - + ]: 286 : if (sbsref->refassgnexpr == NULL)
8138 tgl@sss.pgh.pa.us 1263 :UBC 0 : return NULL;
1264 : :
2788 alvherre@alvh.no-ip. 1265 :CBC 286 : return (Node *) sbsref->refexpr;
1266 : : }
1267 : :
8138 tgl@sss.pgh.pa.us 1268 : 237 : return NULL;
1269 : : }
1270 : :
1271 : : /*
1272 : : * Make an expression tree for the default value for a column.
1273 : : *
1274 : : * If there is no default, return a NULL instead.
1275 : : */
1276 : : Node *
8934 1277 : 99044 : build_column_default(Relation rel, int attrno)
1278 : : {
1279 : 99044 : TupleDesc rd_att = rel->rd_att;
3318 andres@anarazel.de 1280 : 99044 : Form_pg_attribute att_tup = TupleDescAttr(rd_att, attrno - 1);
8934 tgl@sss.pgh.pa.us 1281 : 99044 : Oid atttype = att_tup->atttypid;
1282 : 99044 : int32 atttypmod = att_tup->atttypmod;
1283 : 99044 : Node *expr = NULL;
1284 : : Oid exprtype;
1285 : :
3152 peter_e@gmx.net 1286 [ + + ]: 99044 : if (att_tup->attidentity)
1287 : : {
1288 : 323 : NextValueExpr *nve = makeNode(NextValueExpr);
1289 : :
866 peter@eisentraut.org 1290 : 323 : nve->seqid = getIdentitySequence(rel, attrno, false);
3152 peter_e@gmx.net 1291 : 323 : nve->typeId = att_tup->atttypid;
1292 : :
1293 : 323 : return (Node *) nve;
1294 : : }
1295 : :
1296 : : /*
1297 : : * If relation has a default for this column, fetch that expression.
1298 : : */
1993 tgl@sss.pgh.pa.us 1299 [ + + ]: 98721 : if (att_tup->atthasdef)
1300 : : {
1089 peter@eisentraut.org 1301 : 77320 : expr = TupleDescGetDefault(rd_att, attrno);
1993 tgl@sss.pgh.pa.us 1302 [ - + ]: 77320 : if (expr == NULL)
1993 tgl@sss.pgh.pa.us 1303 [ # # ]:UBC 0 : elog(ERROR, "default expression not found for attribute %d of relation \"%s\"",
1304 : : attrno, RelationGetRelationName(rel));
1305 : : }
1306 : :
1307 : : /*
1308 : : * No per-column default, so look for a default for the type itself. But
1309 : : * not for generated columns.
1310 : : */
2731 peter@eisentraut.org 1311 [ + + + - ]:CBC 98721 : if (expr == NULL && !att_tup->attgenerated)
8207 tgl@sss.pgh.pa.us 1312 : 21401 : expr = get_typdefault(atttype);
1313 : :
8934 1314 [ + + ]: 98721 : if (expr == NULL)
1315 : 21248 : return NULL; /* No default anywhere */
1316 : :
1317 : : /*
1318 : : * Make sure the value is coerced to the target column type; this will
1319 : : * generally be true already, but there seem to be some corner cases
1320 : : * involving domain defaults where it might not be true. This should match
1321 : : * the parser's processing of non-defaulted expressions --- see
1322 : : * transformAssignedExpr().
1323 : : */
1324 : 77473 : exprtype = exprType(expr);
1325 : :
8448 bruce@momjian.us 1326 : 77473 : expr = coerce_to_target_type(NULL, /* no UNKNOWN params here */
1327 : : expr, exprtype,
1328 : : atttype, atttypmod,
1329 : : COERCION_ASSIGNMENT,
1330 : : COERCE_IMPLICIT_CAST,
1331 : : -1);
8768 tgl@sss.pgh.pa.us 1332 [ - + ]: 77473 : if (expr == NULL)
8458 tgl@sss.pgh.pa.us 1333 [ # # ]:UBC 0 : ereport(ERROR,
1334 : : (errcode(ERRCODE_DATATYPE_MISMATCH),
1335 : : errmsg("column \"%s\" is of type %s"
1336 : : " but default expression is of type %s",
1337 : : NameStr(att_tup->attname),
1338 : : format_type_be(atttype),
1339 : : format_type_be(exprtype)),
1340 : : errhint("You will need to rewrite or cast the expression.")));
1341 : :
8934 tgl@sss.pgh.pa.us 1342 :CBC 77473 : return expr;
1343 : : }
1344 : :
1345 : :
1346 : : /* Does VALUES RTE contain any SetToDefault items? */
1347 : : static bool
7354 mail@joeconway.com 1348 : 3187 : searchForDefault(RangeTblEntry *rte)
1349 : : {
1350 : : ListCell *lc;
1351 : :
1352 [ + - + + : 13006 : foreach(lc, rte->values_lists)
+ + ]
1353 : : {
7291 bruce@momjian.us 1354 : 10026 : List *sublist = (List *) lfirst(lc);
1355 : : ListCell *lc2;
1356 : :
7354 mail@joeconway.com 1357 [ + - + + : 29609 : foreach(lc2, sublist)
+ + ]
1358 : : {
7291 bruce@momjian.us 1359 : 19790 : Node *col = (Node *) lfirst(lc2);
1360 : :
7354 mail@joeconway.com 1361 [ + + ]: 19790 : if (IsA(col, SetToDefault))
1362 : 207 : return true;
1363 : : }
1364 : : }
1365 : 2980 : return false;
1366 : : }
1367 : :
1368 : :
1369 : : /*
1370 : : * Search a VALUES RTE for columns that contain only SetToDefault items,
1371 : : * returning a Bitmapset containing the attribute numbers of any such columns.
1372 : : */
1373 : : static Bitmapset *
2128 tgl@sss.pgh.pa.us 1374 : 99 : findDefaultOnlyColumns(RangeTblEntry *rte)
1375 : : {
1376 : 99 : Bitmapset *default_only_cols = NULL;
1377 : : ListCell *lc;
1378 : :
1379 [ + - + + : 189 : foreach(lc, rte->values_lists)
+ + ]
1380 : : {
1381 : 158 : List *sublist = (List *) lfirst(lc);
1382 : : ListCell *lc2;
1383 : : int i;
1384 : :
1385 [ + + ]: 158 : if (default_only_cols == NULL)
1386 : : {
1387 : : /* Populate the initial result bitmap from the first row */
1388 : 99 : i = 0;
1389 [ + - + + : 305 : foreach(lc2, sublist)
+ + ]
1390 : : {
1391 : 206 : Node *col = (Node *) lfirst(lc2);
1392 : :
1393 : 206 : i++;
1394 [ + + ]: 206 : if (IsA(col, SetToDefault))
1395 : 52 : default_only_cols = bms_add_member(default_only_cols, i);
1396 : : }
1397 : : }
1398 : : else
1399 : : {
1400 : : /* Update the result bitmap from this next row */
1401 : 59 : i = 0;
1402 [ + - + + : 193 : foreach(lc2, sublist)
+ + ]
1403 : : {
1404 : 134 : Node *col = (Node *) lfirst(lc2);
1405 : :
1406 : 134 : i++;
1407 [ + + ]: 134 : if (!IsA(col, SetToDefault))
1408 : 94 : default_only_cols = bms_del_member(default_only_cols, i);
1409 : : }
1410 : : }
1411 : :
1412 : : /*
1413 : : * If no column in the rows read so far contains only DEFAULT items,
1414 : : * we are done.
1415 : : */
1416 [ + + ]: 158 : if (bms_is_empty(default_only_cols))
1417 : 68 : break;
1418 : : }
1419 : :
1420 : 99 : return default_only_cols;
1421 : : }
1422 : :
1423 : :
1424 : : /*
1425 : : * When processing INSERT ... VALUES with a VALUES RTE (ie, multiple VALUES
1426 : : * lists), we have to replace any DEFAULT items in the VALUES lists with
1427 : : * the appropriate default expressions. The other aspects of targetlist
1428 : : * rewriting need be applied only to the query's targetlist proper.
1429 : : *
1430 : : * For an auto-updatable view, each DEFAULT item in the VALUES list is
1431 : : * replaced with the default from the view, if it has one. Otherwise it is
1432 : : * left untouched so that the underlying base relation's default can be
1433 : : * applied instead (when we later recurse to here after rewriting the query
1434 : : * to refer to the base relation instead of the view).
1435 : : *
1436 : : * For other types of relation, including rule- and trigger-updatable views,
1437 : : * all DEFAULT items are replaced, and if the target relation doesn't have a
1438 : : * default, the value is explicitly set to NULL.
1439 : : *
1440 : : * Also, if a DEFAULT item is found in a column mentioned in unused_cols,
1441 : : * it is explicitly set to NULL. This happens for columns in the VALUES RTE
1442 : : * whose corresponding targetlist entries have already been replaced with the
1443 : : * relation's default expressions, so that any values in those columns of the
1444 : : * VALUES RTE are no longer used. This can happen for identity and generated
1445 : : * columns (if INSERT ... OVERRIDING USER VALUE is used, or all the values to
1446 : : * be inserted are DEFAULT). In principle we could replace all entries in
1447 : : * such a column with NULL, whether DEFAULT or not; but it doesn't seem worth
1448 : : * the trouble.
1449 : : *
1450 : : * Note that we may have subscripted or field assignment targetlist entries,
1451 : : * as well as more complex expressions from already-replaced DEFAULT items if
1452 : : * we have recursed to here for an auto-updatable view. However, it ought to
1453 : : * be impossible for such entries to have DEFAULTs assigned to them, except
1454 : : * for unused columns, as described above --- we should only have to replace
1455 : : * DEFAULT items for targetlist entries that contain simple Vars referencing
1456 : : * the VALUES RTE, or which are no longer referred to by the targetlist.
1457 : : *
1458 : : * Returns true if all DEFAULT items were replaced, and false if some were
1459 : : * left untouched.
1460 : : */
1461 : : static bool
2758 dean.a.rasheed@gmail 1462 : 3187 : rewriteValuesRTE(Query *parsetree, RangeTblEntry *rte, int rti,
1463 : : Relation target_relation,
1464 : : Bitmapset *unused_cols)
1465 : : {
1466 : : List *newValues;
1467 : : ListCell *lc;
1468 : : bool isAutoUpdatableView;
1469 : : bool allReplaced;
1470 : : int numattrs;
1471 : : int *attrnos;
1472 : :
1473 : : /* Steps below are not sensible for non-INSERT queries */
1440 tgl@sss.pgh.pa.us 1474 [ - + ]: 3187 : Assert(parsetree->commandType == CMD_INSERT);
1475 [ - + ]: 3187 : Assert(rte->rtekind == RTE_VALUES);
1476 : :
1477 : : /*
1478 : : * Rebuilding all the lists is a pretty expensive proposition in a big
1479 : : * VALUES list, and it's a waste of time if there aren't any DEFAULT
1480 : : * placeholders. So first scan to see if there are any.
1481 : : */
1482 [ + + ]: 3187 : if (!searchForDefault(rte))
2769 dean.a.rasheed@gmail 1483 : 2980 : return true; /* nothing to do */
1484 : :
1485 : : /*
1486 : : * Scan the targetlist for entries referring to the VALUES RTE, and note
1487 : : * the target attributes. As noted above, we should only need to do this
1488 : : * for targetlist entries containing simple Vars --- nothing else in the
1489 : : * VALUES RTE should contain DEFAULT items (except possibly for unused
1490 : : * columns), and we complain if such a thing does occur.
1491 : : */
2758 1492 : 207 : numattrs = list_length(linitial(rte->values_lists));
34 michael@paquier.xyz 1493 :GNC 207 : attrnos = palloc0_array(int, numattrs);
1494 : :
2758 dean.a.rasheed@gmail 1495 [ + - + + :CBC 832 : foreach(lc, parsetree->targetList)
+ + ]
1496 : : {
1497 : 625 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
1498 : :
1499 [ + + ]: 625 : if (IsA(tle->expr, Var))
1500 : : {
1501 : 535 : Var *var = (Var *) tle->expr;
1502 : :
1503 [ + - ]: 535 : if (var->varno == rti)
1504 : : {
1505 : 535 : int attrno = var->varattno;
1506 : :
1507 [ + - - + ]: 535 : Assert(attrno >= 1 && attrno <= numattrs);
1508 : 535 : attrnos[attrno - 1] = tle->resno;
1509 : : }
1510 : : }
1511 : : }
1512 : :
1513 : : /*
1514 : : * Check if the target relation is an auto-updatable view, in which case
1515 : : * unresolved defaults will be left untouched rather than being set to
1516 : : * NULL.
1517 : : */
2769 1518 : 207 : isAutoUpdatableView = false;
1440 tgl@sss.pgh.pa.us 1519 [ + + ]: 207 : if (target_relation->rd_rel->relkind == RELKIND_VIEW &&
934 dean.a.rasheed@gmail 1520 [ + + ]: 76 : !view_has_instead_trigger(target_relation, CMD_INSERT, NIL))
1521 : : {
1522 : : List *locks;
1523 : : bool hasUpdate;
1524 : : bool found;
1525 : : ListCell *l;
1526 : :
1527 : : /* Look for an unconditional DO INSTEAD rule */
1528 : 68 : locks = matchLocks(CMD_INSERT, target_relation,
1529 : : parsetree->resultRelation, parsetree, &hasUpdate);
1530 : :
2769 1531 : 68 : found = false;
1532 [ + + + + : 84 : foreach(l, locks)
+ + ]
1533 : : {
1534 : 24 : RewriteRule *rule_lock = (RewriteRule *) lfirst(l);
1535 : :
1536 [ + + ]: 24 : if (rule_lock->isInstead &&
1537 [ + - ]: 8 : rule_lock->qual == NULL)
1538 : : {
1539 : 8 : found = true;
1540 : 8 : break;
1541 : : }
1542 : : }
1543 : :
1544 : : /*
1545 : : * If we didn't find an unconditional DO INSTEAD rule, assume that the
1546 : : * view is auto-updatable. If it isn't, rewriteTargetView() will
1547 : : * throw an error.
1548 : : */
1549 [ + + ]: 68 : if (!found)
1550 : 60 : isAutoUpdatableView = true;
1551 : : }
1552 : :
7354 mail@joeconway.com 1553 : 207 : newValues = NIL;
2769 dean.a.rasheed@gmail 1554 : 207 : allReplaced = true;
7354 mail@joeconway.com 1555 [ + - + + : 637 : foreach(lc, rte->values_lists)
+ + ]
1556 : : {
7291 bruce@momjian.us 1557 : 430 : List *sublist = (List *) lfirst(lc);
1558 : 430 : List *newList = NIL;
1559 : : ListCell *lc2;
1560 : : int i;
1561 : :
2758 dean.a.rasheed@gmail 1562 [ - + ]: 430 : Assert(list_length(sublist) == numattrs);
1563 : :
1564 : 430 : i = 0;
1565 [ + - + + : 1710 : foreach(lc2, sublist)
+ + ]
1566 : : {
7291 bruce@momjian.us 1567 : 1280 : Node *col = (Node *) lfirst(lc2);
2758 dean.a.rasheed@gmail 1568 : 1280 : int attrno = attrnos[i++];
1569 : :
7354 mail@joeconway.com 1570 [ + + ]: 1280 : if (IsA(col, SetToDefault))
1571 : : {
1572 : : Form_pg_attribute att_tup;
1573 : : Node *new_expr;
1574 : :
1575 : : /*
1576 : : * If this column isn't used, just replace the DEFAULT with
1577 : : * NULL (attrno will be 0 in this case because the targetlist
1578 : : * entry will have been replaced by the default expression).
1579 : : */
2128 tgl@sss.pgh.pa.us 1580 [ + + ]: 592 : if (bms_is_member(i, unused_cols))
1581 : 86 : {
1582 : 86 : SetToDefault *def = (SetToDefault *) col;
1583 : :
1584 : 86 : newList = lappend(newList,
1585 : 86 : makeNullConst(def->typeId,
1586 : : def->typeMod,
1587 : : def->collation));
1588 : 86 : continue;
1589 : : }
1590 : :
2758 dean.a.rasheed@gmail 1591 [ - + ]: 506 : if (attrno == 0)
2758 dean.a.rasheed@gmail 1592 [ # # ]:UBC 0 : elog(ERROR, "cannot set value in column %d to DEFAULT", i);
1440 tgl@sss.pgh.pa.us 1593 [ + - - + ]:CBC 506 : Assert(attrno > 0 && attrno <= target_relation->rd_att->natts);
3318 andres@anarazel.de 1594 : 506 : att_tup = TupleDescAttr(target_relation->rd_att, attrno - 1);
1595 : :
1440 tgl@sss.pgh.pa.us 1596 [ + - ]: 506 : if (!att_tup->attisdropped)
7354 mail@joeconway.com 1597 : 506 : new_expr = build_column_default(target_relation, attrno);
1598 : : else
7291 bruce@momjian.us 1599 :UBC 0 : new_expr = NULL; /* force a NULL if dropped */
1600 : :
1601 : : /*
1602 : : * If there is no default (ie, default is effectively NULL),
1603 : : * we've got to explicitly set the column to NULL, unless the
1604 : : * target relation is an auto-updatable view.
1605 : : */
7354 mail@joeconway.com 1606 [ + + ]:CBC 506 : if (!new_expr)
1607 : : {
2769 dean.a.rasheed@gmail 1608 [ + + ]: 238 : if (isAutoUpdatableView)
1609 : : {
1610 : : /* Leave the value untouched */
1611 : 100 : newList = lappend(newList, col);
1612 : 100 : allReplaced = false;
1613 : 100 : continue;
1614 : : }
1615 : :
599 tgl@sss.pgh.pa.us 1616 : 138 : new_expr = coerce_null_to_domain(att_tup->atttypid,
1617 : : att_tup->atttypmod,
1618 : : att_tup->attcollation,
1619 : 138 : att_tup->attlen,
1620 : 138 : att_tup->attbyval);
1621 : : }
7354 mail@joeconway.com 1622 : 406 : newList = lappend(newList, new_expr);
1623 : : }
1624 : : else
1625 : 688 : newList = lappend(newList, col);
1626 : : }
1627 : 430 : newValues = lappend(newValues, newList);
1628 : : }
1629 : 207 : rte->values_lists = newValues;
1630 : :
2758 dean.a.rasheed@gmail 1631 : 207 : pfree(attrnos);
1632 : :
2769 1633 : 207 : return allReplaced;
1634 : : }
1635 : :
1636 : : /*
1637 : : * Mop up any remaining DEFAULT items in the given VALUES RTE by
1638 : : * replacing them with NULL constants.
1639 : : *
1640 : : * This is used for the product queries generated by DO ALSO rules attached to
1641 : : * an auto-updatable view. The action can't depend on the "target relation"
1642 : : * since the product query might not have one (it needn't be an INSERT).
1643 : : * Essentially, such queries are treated as being attached to a rule-updatable
1644 : : * view.
1645 : : */
1646 : : static void
1440 tgl@sss.pgh.pa.us 1647 : 16 : rewriteValuesRTEToNulls(Query *parsetree, RangeTblEntry *rte)
1648 : : {
1649 : : List *newValues;
1650 : : ListCell *lc;
1651 : :
1652 : 16 : newValues = NIL;
1653 [ + - + + : 48 : foreach(lc, rte->values_lists)
+ + ]
1654 : : {
1655 : 32 : List *sublist = (List *) lfirst(lc);
1656 : 32 : List *newList = NIL;
1657 : : ListCell *lc2;
1658 : :
1659 [ + - + + : 136 : foreach(lc2, sublist)
+ + ]
1660 : : {
1661 : 104 : Node *col = (Node *) lfirst(lc2);
1662 : :
1663 [ + + ]: 104 : if (IsA(col, SetToDefault))
1664 : : {
1665 : 44 : SetToDefault *def = (SetToDefault *) col;
1666 : :
1667 : 44 : newList = lappend(newList, makeNullConst(def->typeId,
1668 : : def->typeMod,
1669 : : def->collation));
1670 : : }
1671 : : else
1672 : 60 : newList = lappend(newList, col);
1673 : : }
1674 : 32 : newValues = lappend(newValues, newList);
1675 : : }
1676 : 16 : rte->values_lists = newValues;
1677 : 16 : }
1678 : :
1679 : :
1680 : : /*
1681 : : * matchLocks -
1682 : : * match a relation's list of locks and returns the matching rules
1683 : : */
1684 : : static List *
9487 1685 : 58060 : matchLocks(CmdType event,
1686 : : Relation relation,
1687 : : int varno,
1688 : : Query *parsetree,
1689 : : bool *hasUpdate)
1690 : : {
934 dean.a.rasheed@gmail 1691 : 58060 : RuleLock *rulelocks = relation->rd_rules;
8737 tgl@sss.pgh.pa.us 1692 : 58060 : List *matching_locks = NIL;
1693 : : int nlocks;
1694 : : int i;
1695 : :
8608 1696 [ + + ]: 58060 : if (rulelocks == NULL)
1697 : 54167 : return NIL;
1698 : :
9487 1699 [ + - ]: 3893 : if (parsetree->commandType != CMD_SELECT)
1700 : : {
1701 [ - + ]: 3893 : if (parsetree->resultRelation != varno)
9487 tgl@sss.pgh.pa.us 1702 :UBC 0 : return NIL;
1703 : : }
1704 : :
9487 tgl@sss.pgh.pa.us 1705 :CBC 3893 : nlocks = rulelocks->numLocks;
1706 : :
1707 [ + + ]: 8886 : for (i = 0; i < nlocks; i++)
1708 : : {
1709 : 5005 : RewriteRule *oneLock = rulelocks->rules[i];
1710 : :
4153 andres@anarazel.de 1711 [ + + ]: 5005 : if (oneLock->event == CMD_UPDATE)
1712 : 472 : *hasUpdate = true;
1713 : :
1714 : : /*
1715 : : * Suppress ON INSERT/UPDATE/DELETE rules that are disabled or
1716 : : * configured to not fire during the current session's replication
1717 : : * role. ON SELECT rules will always be applied in order to keep views
1718 : : * working even in LOCAL or REPLICA role.
1719 : : */
7125 JanWieck@Yahoo.com 1720 [ + + ]: 5005 : if (oneLock->event != CMD_SELECT)
1721 : : {
1722 [ + + ]: 1900 : if (SessionReplicationRole == SESSION_REPLICATION_ROLE_REPLICA)
1723 : : {
1724 [ + + ]: 8 : if (oneLock->enabled == RULE_FIRES_ON_ORIGIN ||
1725 [ - + ]: 4 : oneLock->enabled == RULE_DISABLED)
1726 : 4 : continue;
1727 : : }
1728 : : else /* ORIGIN or LOCAL ROLE */
1729 : : {
1730 [ + + ]: 1892 : if (oneLock->enabled == RULE_FIRES_ON_REPLICA ||
1731 [ + + ]: 1888 : oneLock->enabled == RULE_DISABLED)
1732 : 20 : continue;
1733 : : }
1734 : :
1735 : : /* Non-SELECT rules are not supported for MERGE */
934 dean.a.rasheed@gmail 1736 [ + + ]: 1876 : if (parsetree->commandType == CMD_MERGE)
1737 [ + - ]: 12 : ereport(ERROR,
1738 : : errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1739 : : errmsg("cannot execute MERGE on relation \"%s\"",
1740 : : RelationGetRelationName(relation)),
1741 : : errdetail("MERGE is not supported for relations with rules."));
1742 : : }
1743 : :
9487 tgl@sss.pgh.pa.us 1744 [ + + ]: 4969 : if (oneLock->event == event)
1745 : : {
1746 [ - + - - ]: 1112 : if (parsetree->commandType != CMD_SELECT ||
4763 kgrittn@postgresql.o 1747 :UBC 0 : rangeTableEntry_used((Node *) parsetree, varno, 0))
8737 tgl@sss.pgh.pa.us 1748 :CBC 1112 : matching_locks = lappend(matching_locks, oneLock);
1749 : : }
1750 : : }
1751 : :
1752 : 3881 : return matching_locks;
1753 : : }
1754 : :
1755 : :
1756 : : /*
1757 : : * ApplyRetrieveRule - expand an ON SELECT rule
1758 : : */
1759 : : static Query *
9487 1760 : 10636 : ApplyRetrieveRule(Query *parsetree,
1761 : : RewriteRule *rule,
1762 : : int rt_index,
1763 : : Relation relation,
1764 : : List *activeRIRs)
1765 : : {
1766 : : Query *rule_action;
1767 : : RangeTblEntry *rte;
1768 : : RowMarkClause *rc;
1769 : : int numCols;
1770 : :
8148 neilc@samurai.com 1771 [ - + ]: 10636 : if (list_length(rule->actions) != 1)
8458 tgl@sss.pgh.pa.us 1772 [ # # ]:UBC 0 : elog(ERROR, "expected just one rule action");
9487 tgl@sss.pgh.pa.us 1773 [ - + ]:CBC 10636 : if (rule->qual != NULL)
8458 tgl@sss.pgh.pa.us 1774 [ # # ]:UBC 0 : elog(ERROR, "cannot handle qualified ON SELECT rule");
1775 : :
1776 : : /* Check if the expansion of non-system views are restricted */
776 msawada@postgresql.o 1777 [ + + + + :CBC 10636 : if (unlikely((restrict_nonsystem_relation_kind & RESTRICT_RELKIND_VIEW) != 0 &&
+ + ]
1778 : : RelationGetRelid(relation) >= FirstNormalObjectId))
1779 [ + - ]: 4 : ereport(ERROR,
1780 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
1781 : : errmsg("access to non-system view \"%s\" is restricted",
1782 : : RelationGetRelationName(relation))));
1783 : :
5824 tgl@sss.pgh.pa.us 1784 [ + + ]: 10632 : if (rt_index == parsetree->resultRelation)
1785 : : {
1786 : : /*
1787 : : * We have a view as the result relation of the query, and it wasn't
1788 : : * rewritten by any rule. This case is supported if there is an
1789 : : * INSTEAD OF trigger that will trap attempts to insert/update/delete
1790 : : * view rows. The executor will check that; for the moment just plow
1791 : : * ahead. We have two cases:
1792 : : *
1793 : : * For INSERT, we needn't do anything. The unmodified RTE will serve
1794 : : * fine as the result relation.
1795 : : *
1796 : : * For UPDATE/DELETE/MERGE, we need to expand the view so as to have
1797 : : * source data for the operation. But we also need an unmodified RTE
1798 : : * to serve as the target. So, copy the RTE and add the copy to the
1799 : : * rangetable. Note that the copy does not get added to the jointree.
1800 : : * Also note that there's a hack in fireRIRrules to avoid calling this
1801 : : * function again when it arrives at the copied RTE.
1802 : : */
1803 [ + + ]: 269 : if (parsetree->commandType == CMD_INSERT)
1804 : 79 : return parsetree;
1805 [ + + ]: 190 : else if (parsetree->commandType == CMD_UPDATE ||
934 dean.a.rasheed@gmail 1806 [ + + ]: 87 : parsetree->commandType == CMD_DELETE ||
1807 [ + - ]: 52 : parsetree->commandType == CMD_MERGE)
5824 tgl@sss.pgh.pa.us 1808 : 190 : {
1809 : : RangeTblEntry *newrte;
1810 : : Var *var;
1811 : : TargetEntry *tle;
1812 : :
1813 : 190 : rte = rt_fetch(rt_index, parsetree->rtable);
1814 : 190 : newrte = copyObject(rte);
1815 : 190 : parsetree->rtable = lappend(parsetree->rtable, newrte);
1816 : 190 : parsetree->resultRelation = list_length(parsetree->rtable);
1817 : : /* parsetree->mergeTargetRelation unchanged (use expanded view) */
1818 : :
1819 : : /*
1820 : : * For the most part, Vars referencing the view should remain as
1821 : : * they are, meaning that they implicitly represent OLD values.
1822 : : * But in the RETURNING list if any, we want such Vars to
1823 : : * represent NEW values, so change them to reference the new RTE.
1824 : : *
1825 : : * Since ChangeVarNodes scribbles on the tree in-place, copy the
1826 : : * RETURNING list first for safety.
1827 : : */
1828 : 190 : parsetree->returningList = copyObject(parsetree->returningList);
1829 : 190 : ChangeVarNodes((Node *) parsetree->returningList, rt_index,
1830 : : parsetree->resultRelation, 0);
1831 : :
1832 : : /*
1833 : : * To allow the executor to compute the original view row to pass
1834 : : * to the INSTEAD OF trigger, we add a resjunk whole-row Var
1835 : : * referencing the original RTE. This will later get expanded
1836 : : * into a RowExpr computing all the OLD values of the view row.
1837 : : */
3219 1838 : 190 : var = makeWholeRowVar(rte, rt_index, 0, false);
1839 : 190 : tle = makeTargetEntry((Expr *) var,
1840 : 190 : list_length(parsetree->targetList) + 1,
1841 : : pstrdup("wholerow"),
1842 : : true);
1843 : :
1844 : 190 : parsetree->targetList = lappend(parsetree->targetList, tle);
1845 : :
1846 : : /* Now, continue with expanding the original view RTE */
1847 : : }
1848 : : else
5824 tgl@sss.pgh.pa.us 1849 [ # # ]:UBC 0 : elog(ERROR, "unrecognized commandType: %d",
1850 : : (int) parsetree->commandType);
1851 : : }
1852 : :
1853 : : /*
1854 : : * Check if there's a FOR [KEY] UPDATE/SHARE clause applying to this view.
1855 : : *
1856 : : * Note: we needn't explicitly consider any such clauses appearing in
1857 : : * ancestor query levels; their effects have already been pushed down to
1858 : : * here by markQueryForLocking, and will be reflected in "rc".
1859 : : */
6171 tgl@sss.pgh.pa.us 1860 :CBC 10553 : rc = get_parse_rowmark(parsetree, rt_index);
1861 : :
1862 : : /*
1863 : : * Make a modifiable copy of the view query, and acquire needed locks on
1864 : : * the relations it mentions. Force at least RowShareLock for all such
1865 : : * rels if there's a FOR [KEY] UPDATE/SHARE clause affecting this view.
1866 : : */
8152 neilc@samurai.com 1867 : 10553 : rule_action = copyObject(linitial(rule->actions));
1868 : :
3081 tgl@sss.pgh.pa.us 1869 : 10553 : AcquireRewriteLocks(rule_action, true, (rc != NULL));
1870 : :
1871 : : /*
1872 : : * If FOR [KEY] UPDATE/SHARE of view, mark all the contained tables as
1873 : : * implicit FOR [KEY] UPDATE/SHARE, the same as the parser would have done
1874 : : * if the view's subquery had been written out explicitly.
1875 : : */
1876 [ + + ]: 10553 : if (rc != NULL)
1877 : 64 : markQueryForLocking(rule_action, (Node *) rule_action->jointree,
1878 : : rc->strength, rc->waitPolicy, true);
1879 : :
1880 : : /*
1881 : : * Recursively expand any view references inside the view.
1882 : : */
1883 : 10553 : rule_action = fireRIRrules(rule_action, activeRIRs);
1884 : :
1885 : : /*
1886 : : * Make sure the query is marked as having row security if the view query
1887 : : * does.
1888 : : */
678 nathan@postgresql.or 1889 : 10533 : parsetree->hasRowSecurity |= rule_action->hasRowSecurity;
1890 : :
1891 : : /*
1892 : : * Now, plug the view query in as a subselect, converting the relation's
1893 : : * original RTE to a subquery RTE.
1894 : : */
9487 tgl@sss.pgh.pa.us 1895 : 10533 : rte = rt_fetch(rt_index, parsetree->rtable);
1896 : :
8958 1897 : 10533 : rte->rtekind = RTE_SUBQUERY;
9487 1898 : 10533 : rte->subquery = rule_action;
2924 1899 [ - + + + ]: 10533 : rte->security_barrier = RelationIsSecurityView(relation);
1900 : :
1901 : : /*
1902 : : * Clear fields that should not be set in a subquery RTE. Note that we
1903 : : * leave the relid, relkind, rellockmode, and perminfoindex fields set, so
1904 : : * that the view relation can be appropriately locked before execution and
1905 : : * its permissions checked.
1906 : : */
1341 1907 : 10533 : rte->tablesample = NULL;
1908 : 10533 : rte->inh = false; /* must not be set for a subquery */
1909 : :
1910 : : /*
1911 : : * Since we allow CREATE OR REPLACE VIEW to add columns to a view, the
1912 : : * rule_action might emit more columns than we expected when the current
1913 : : * query was parsed. Various places expect rte->eref->colnames to be
1914 : : * consistent with the non-junk output columns of the subquery, so patch
1915 : : * things up if necessary by adding some dummy column names.
1916 : : */
1293 1917 : 10533 : numCols = ExecCleanTargetListLength(rule_action->targetList);
1918 [ + + ]: 10545 : while (list_length(rte->eref->colnames) < numCols)
1919 : : {
1920 : 12 : rte->eref->colnames = lappend(rte->eref->colnames,
1921 : 12 : makeString(pstrdup("?column?")));
1922 : : }
1923 : :
9851 1924 : 10533 : return parsetree;
1925 : : }
1926 : :
1927 : : /*
1928 : : * Recursively mark all relations used by a view as FOR [KEY] UPDATE/SHARE.
1929 : : *
1930 : : * This may generate an invalid query, eg if some sub-query uses an
1931 : : * aggregate. We leave it to the planner to detect that.
1932 : : *
1933 : : * NB: this must agree with the parser's transformLockingClause() routine.
1934 : : * However, we used to have to avoid marking a view's OLD and NEW rels for
1935 : : * updating, which motivated scanning the jointree to determine which rels
1936 : : * are used. Possibly that could now be simplified into just scanning the
1937 : : * rangetable as the parser does.
1938 : : */
1939 : : static void
6171 1940 : 128 : markQueryForLocking(Query *qry, Node *jtnode,
1941 : : LockClauseStrength strength, LockWaitPolicy waitPolicy,
1942 : : bool pushedDown)
1943 : : {
7143 1944 [ - + ]: 128 : if (jtnode == NULL)
7143 tgl@sss.pgh.pa.us 1945 :UBC 0 : return;
7143 tgl@sss.pgh.pa.us 1946 [ + + ]:CBC 128 : if (IsA(jtnode, RangeTblRef))
1947 : : {
1948 : 64 : int rti = ((RangeTblRef *) jtnode)->rtindex;
1949 : 64 : RangeTblEntry *rte = rt_fetch(rti, qry->rtable);
1950 : :
8958 1951 [ + - ]: 64 : if (rte->rtekind == RTE_RELATION)
1952 : : {
1953 : : RTEPermissionInfo *perminfo;
1954 : :
4366 alvherre@alvh.no-ip. 1955 : 64 : applyLockingClause(qry, rti, strength, waitPolicy, pushedDown);
1956 : :
1384 1957 : 64 : perminfo = getRTEPermissionInfo(qry->rteperminfos, rte);
1958 : 64 : perminfo->requiredPerms |= ACL_SELECT_FOR_UPDATE;
1959 : : }
8958 tgl@sss.pgh.pa.us 1960 [ # # ]:UBC 0 : else if (rte->rtekind == RTE_SUBQUERY)
1961 : : {
4366 alvherre@alvh.no-ip. 1962 : 0 : applyLockingClause(qry, rti, strength, waitPolicy, pushedDown);
1963 : : /* FOR UPDATE/SHARE of subquery is propagated to subquery's rels */
7143 tgl@sss.pgh.pa.us 1964 : 0 : markQueryForLocking(rte->subquery, (Node *) rte->subquery->jointree,
1965 : : strength, waitPolicy, true);
1966 : : }
1967 : : /* other RTE types are unaffected by FOR UPDATE */
1968 : : }
7143 tgl@sss.pgh.pa.us 1969 [ + - ]:CBC 64 : else if (IsA(jtnode, FromExpr))
1970 : : {
1971 : 64 : FromExpr *f = (FromExpr *) jtnode;
1972 : : ListCell *l;
1973 : :
1974 [ + - + + : 128 : foreach(l, f->fromlist)
+ + ]
4366 alvherre@alvh.no-ip. 1975 : 64 : markQueryForLocking(qry, lfirst(l), strength, waitPolicy, pushedDown);
1976 : : }
7143 tgl@sss.pgh.pa.us 1977 [ # # ]:UBC 0 : else if (IsA(jtnode, JoinExpr))
1978 : : {
1979 : 0 : JoinExpr *j = (JoinExpr *) jtnode;
1980 : :
4366 alvherre@alvh.no-ip. 1981 : 0 : markQueryForLocking(qry, j->larg, strength, waitPolicy, pushedDown);
1982 : 0 : markQueryForLocking(qry, j->rarg, strength, waitPolicy, pushedDown);
1983 : : }
1984 : : else
7143 tgl@sss.pgh.pa.us 1985 [ # # ]: 0 : elog(ERROR, "unrecognized node type: %d",
1986 : : (int) nodeTag(jtnode));
1987 : : }
1988 : :
1989 : :
1990 : : /*
1991 : : * fireRIRonSubLink -
1992 : : * Apply fireRIRrules() to each SubLink (subselect in expression) found
1993 : : * in the given tree.
1994 : : *
1995 : : * NOTE: although this has the form of a walker, we cheat and modify the
1996 : : * SubLink nodes in-place. It is caller's responsibility to ensure that
1997 : : * no unwanted side-effects occur!
1998 : : *
1999 : : * This is unlike most of the other routines that recurse into subselects,
2000 : : * because we must take control at the SubLink node in order to replace
2001 : : * the SubLink's subselect link with the possibly-rewritten subquery.
2002 : : */
2003 : : static bool
678 nathan@postgresql.or 2004 :CBC 1813506 : fireRIRonSubLink(Node *node, fireRIRonSubLink_context *context)
2005 : : {
10215 bruce@momjian.us 2006 [ + + ]: 1813506 : if (node == NULL)
9851 tgl@sss.pgh.pa.us 2007 : 372282 : return false;
2008 [ + + ]: 1441224 : if (IsA(node, SubLink))
2009 : : {
2010 : 34350 : SubLink *sub = (SubLink *) node;
2011 : :
2012 : : /* Do what we came for */
8608 2013 : 34350 : sub->subselect = (Node *) fireRIRrules((Query *) sub->subselect,
2014 : : context->activeRIRs);
2015 : :
2016 : : /*
2017 : : * Remember if any of the sublinks have row security.
2018 : : */
678 nathan@postgresql.or 2019 : 34302 : context->hasRowSecurity |= ((Query *) sub->subselect)->hasRowSecurity;
2020 : :
2021 : : /* Fall through to process lefthand args of SubLink */
2022 : : }
2023 : :
2024 : : /*
2025 : : * Do NOT recurse into Query nodes, because fireRIRrules already processed
2026 : : * subselects of subselects for us.
2027 : : */
661 peter@eisentraut.org 2028 : 1441176 : return expression_tree_walker(node, fireRIRonSubLink, context);
2029 : : }
2030 : :
2031 : :
2032 : : /*
2033 : : * fireRIRrules -
2034 : : * Apply all RIR rules on each rangetable entry in the given query
2035 : : *
2036 : : * activeRIRs is a list of the OIDs of views we're already processing RIR
2037 : : * rules for, used to detect/reject recursion.
2038 : : */
2039 : : static Query *
3081 tgl@sss.pgh.pa.us 2040 : 367001 : fireRIRrules(Query *parsetree, List *activeRIRs)
2041 : : {
5824 2042 : 367001 : int origResultRelation = parsetree->resultRelation;
2043 : : int rt_index;
2044 : : ListCell *lc;
2045 : :
2046 : : /*
2047 : : * Expand SEARCH and CYCLE clauses in CTEs.
2048 : : *
2049 : : * This is just a convenient place to do this, since we are already
2050 : : * looking at each Query.
2051 : : */
2057 peter@eisentraut.org 2052 [ + + + + : 369690 : foreach(lc, parsetree->cteList)
+ + ]
2053 : : {
2054 : 2693 : CommonTableExpr *cte = lfirst_node(CommonTableExpr, lc);
2055 : :
2056 [ + + + + ]: 2693 : if (cte->search_clause || cte->cycle_clause)
2057 : : {
2058 : 96 : cte = rewriteSearchAndCycle(cte);
2059 : 92 : lfirst(lc) = cte;
2060 : : }
2061 : : }
2062 : :
2063 : : /*
2064 : : * don't try to convert this into a foreach loop, because rtable list can
2065 : : * get changed each time through...
2066 : : */
10215 bruce@momjian.us 2067 : 366997 : rt_index = 0;
8148 neilc@samurai.com 2068 [ + + ]: 824087 : while (rt_index < list_length(parsetree->rtable))
2069 : : {
2070 : : RangeTblEntry *rte;
2071 : : Relation rel;
2072 : : List *locks;
2073 : : RuleLock *rules;
2074 : : RewriteRule *rule;
2075 : : int i;
2076 : :
10215 bruce@momjian.us 2077 : 457114 : ++rt_index;
2078 : :
9820 tgl@sss.pgh.pa.us 2079 : 457114 : rte = rt_fetch(rt_index, parsetree->rtable);
2080 : :
2081 : : /*
2082 : : * A subquery RTE can't have associated rules, so there's nothing to
2083 : : * do to this level of the query, but we must recurse into the
2084 : : * subquery to expand any rule references in it.
2085 : : */
8958 2086 [ + + ]: 457114 : if (rte->rtekind == RTE_SUBQUERY)
2087 : : {
3081 2088 : 37734 : rte->subquery = fireRIRrules(rte->subquery, activeRIRs);
2089 : :
2090 : : /*
2091 : : * While we are here, make sure the query is marked as having row
2092 : : * security if any of its subqueries do.
2093 : : */
678 nathan@postgresql.or 2094 : 37734 : parsetree->hasRowSecurity |= rte->subquery->hasRowSecurity;
2095 : :
9487 tgl@sss.pgh.pa.us 2096 : 37734 : continue;
2097 : : }
2098 : :
2099 : : /*
2100 : : * Joins and other non-relation RTEs can be ignored completely.
2101 : : */
8958 2102 [ + + ]: 419380 : if (rte->rtekind != RTE_RELATION)
2103 : 107793 : continue;
2104 : :
2105 : : /*
2106 : : * Always ignore RIR rules for materialized views referenced in
2107 : : * queries. (This does not prevent refreshing MVs, since they aren't
2108 : : * referenced in their own query definitions.)
2109 : : *
2110 : : * Note: in the future we might want to allow MVs to be conditionally
2111 : : * expanded as if they were regular views, if they are not scannable.
2112 : : * In that case this test would need to be postponed till after we've
2113 : : * opened the rel, so that we could check its state.
2114 : : */
4894 2115 [ + + ]: 311587 : if (rte->relkind == RELKIND_MATVIEW)
2116 : 291 : continue;
2117 : :
2118 : : /*
2119 : : * In INSERT ... ON CONFLICT, ignore the EXCLUDED pseudo-relation;
2120 : : * even if it points to a view, we needn't expand it, and should not
2121 : : * because we want the RTE to remain of RTE_RELATION type. Otherwise,
2122 : : * it would get changed to RTE_SUBQUERY type, which is an
2123 : : * untested/unsupported situation.
2124 : : */
2969 2125 [ + + ]: 311296 : if (parsetree->onConflict &&
2126 [ + + ]: 3265 : rt_index == parsetree->onConflict->exclRelIndex)
2127 : 1206 : continue;
2128 : :
2129 : : /*
2130 : : * If the table is not referenced in the query, then we ignore it.
2131 : : * This prevents infinite expansion loop due to new rtable entries
2132 : : * inserted by expansion of a rule. A table is referenced if it is
2133 : : * part of the join set (a source table), or is referenced by any Var
2134 : : * nodes, or is the result table.
2135 : : */
7784 2136 [ + + ]: 310090 : if (rt_index != parsetree->resultRelation &&
2137 [ + + ]: 254908 : !rangeTableEntry_used((Node *) parsetree, rt_index, 0))
10215 bruce@momjian.us 2138 : 5018 : continue;
2139 : :
2140 : : /*
2141 : : * Also, if this is a new result relation introduced by
2142 : : * ApplyRetrieveRule, we don't want to do anything more with it.
2143 : : */
5824 tgl@sss.pgh.pa.us 2144 [ + + + + ]: 305072 : if (rt_index == parsetree->resultRelation &&
2145 : : rt_index != origResultRelation)
2146 : 190 : continue;
2147 : :
2148 : : /*
2149 : : * We can use NoLock here since either the parser or
2150 : : * AcquireRewriteLocks should have locked the rel already.
2151 : : */
193 peter@eisentraut.org 2152 : 304882 : rel = relation_open(rte->relid, NoLock);
2153 : :
2154 : : /*
2155 : : * Collect the RIR rules that we must apply
2156 : : */
9845 tgl@sss.pgh.pa.us 2157 : 304882 : rules = rel->rd_rules;
4384 sfrost@snowman.net 2158 [ + + ]: 304882 : if (rules != NULL)
2159 : : {
2160 : 11579 : locks = NIL;
2161 [ + + ]: 25408 : for (i = 0; i < rules->numLocks; i++)
2162 : : {
2163 : 13829 : rule = rules->rules[i];
2164 [ + + ]: 13829 : if (rule->event != CMD_SELECT)
2165 : 3193 : continue;
2166 : :
2167 : 10636 : locks = lappend(locks, rule);
2168 : : }
2169 : :
2170 : : /*
2171 : : * If we found any, apply them --- but first check for recursion!
2172 : : */
2173 [ + + ]: 11579 : if (locks != NIL)
2174 : : {
2175 : : ListCell *l;
2176 : :
2177 [ - + ]: 10636 : if (list_member_oid(activeRIRs, RelationGetRelid(rel)))
4384 sfrost@snowman.net 2178 [ # # ]:UBC 0 : ereport(ERROR,
2179 : : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2180 : : errmsg("infinite recursion detected in rules for relation \"%s\"",
2181 : : RelationGetRelationName(rel))));
2622 tgl@sss.pgh.pa.us 2182 :CBC 10636 : activeRIRs = lappend_oid(activeRIRs, RelationGetRelid(rel));
2183 : :
4384 sfrost@snowman.net 2184 [ + - + + : 21248 : foreach(l, locks)
+ + ]
2185 : : {
2186 : 10636 : rule = lfirst(l);
2187 : :
2188 : 10636 : parsetree = ApplyRetrieveRule(parsetree,
2189 : : rule,
2190 : : rt_index,
2191 : : rel,
2192 : : activeRIRs);
2193 : : }
2194 : :
2622 tgl@sss.pgh.pa.us 2195 : 10612 : activeRIRs = list_delete_last(activeRIRs);
2196 : : }
2197 : : }
2198 : :
2799 andres@anarazel.de 2199 : 304858 : table_close(rel, NoLock);
2200 : : }
2201 : :
2202 : : /* Recurse into subqueries in WITH */
6560 tgl@sss.pgh.pa.us 2203 [ + + + + : 369662 : foreach(lc, parsetree->cteList)
+ + ]
2204 : : {
2205 : 2689 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
2206 : :
2207 : 2689 : cte->ctequery = (Node *)
3081 2208 : 2689 : fireRIRrules((Query *) cte->ctequery, activeRIRs);
2209 : :
2210 : : /*
2211 : : * While we are here, make sure the query is marked as having row
2212 : : * security if any of its CTEs do.
2213 : : */
678 nathan@postgresql.or 2214 : 2689 : parsetree->hasRowSecurity |= ((Query *) cte->ctequery)->hasRowSecurity;
2215 : : }
2216 : :
2217 : : /*
2218 : : * Recurse into sublink subqueries, too. But we already did the ones in
2219 : : * the rtable and cteList.
2220 : : */
9487 tgl@sss.pgh.pa.us 2221 [ + + ]: 366973 : if (parsetree->hasSubLinks)
2222 : : {
2223 : : fireRIRonSubLink_context context;
2224 : :
678 nathan@postgresql.or 2225 : 25937 : context.activeRIRs = activeRIRs;
2226 : 25937 : context.hasRowSecurity = false;
2227 : :
661 peter@eisentraut.org 2228 : 25937 : query_tree_walker(parsetree, fireRIRonSubLink, &context,
2229 : : QTW_IGNORE_RC_SUBQUERIES);
2230 : :
2231 : : /*
2232 : : * Make sure the query is marked as having row security if any of its
2233 : : * sublinks do.
2234 : : */
678 nathan@postgresql.or 2235 : 25937 : parsetree->hasRowSecurity |= context.hasRowSecurity;
2236 : : }
2237 : :
2238 : : /*
2239 : : * Apply any row-level security policies. We do this last because it
2240 : : * requires special recursion detection if the new quals have sublink
2241 : : * subqueries, and if we did it in the loop above query_tree_walker would
2242 : : * then recurse into those quals a second time.
2243 : : */
4169 sfrost@snowman.net 2244 : 366973 : rt_index = 0;
2245 [ + + + + : 823947 : foreach(lc, parsetree->rtable)
+ + ]
2246 : : {
2247 : 457090 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
2248 : : Relation rel;
2249 : : List *securityQuals;
2250 : : List *withCheckOptions;
2251 : : bool hasRowSecurity;
2252 : : bool hasSubLinks;
2253 : :
2254 : 457090 : ++rt_index;
2255 : :
2256 : : /* Only normal relations can have RLS policies */
572 rguo@postgresql.org 2257 [ + + ]: 457090 : if (rte->rtekind != RTE_RELATION ||
2258 [ + + ]: 301030 : (rte->relkind != RELKIND_RELATION &&
2259 [ + + ]: 17475 : rte->relkind != RELKIND_PARTITIONED_TABLE))
4169 sfrost@snowman.net 2260 : 162075 : continue;
2261 : :
193 peter@eisentraut.org 2262 : 295015 : rel = relation_open(rte->relid, NoLock);
2263 : :
2264 : : /*
2265 : : * Fetch any new security quals that must be applied to this RTE.
2266 : : */
4023 sfrost@snowman.net 2267 : 295015 : get_row_security_policies(parsetree, rte, rt_index,
2268 : : &securityQuals, &withCheckOptions,
2269 : : &hasRowSecurity, &hasSubLinks);
2270 : :
4169 2271 [ + + + + ]: 294975 : if (securityQuals != NIL || withCheckOptions != NIL)
2272 : : {
2273 [ + + ]: 2168 : if (hasSubLinks)
2274 : : {
2275 : : acquireLocksOnSubLinks_context context;
2276 : : fireRIRonSubLink_context fire_context;
2277 : :
2278 : : /*
2279 : : * Recursively process the new quals, checking for infinite
2280 : : * recursion.
2281 : : */
2282 [ + + ]: 492 : if (list_member_oid(activeRIRs, RelationGetRelid(rel)))
2283 [ + - ]: 28 : ereport(ERROR,
2284 : : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2285 : : errmsg("infinite recursion detected in policy for relation \"%s\"",
2286 : : RelationGetRelationName(rel))));
2287 : :
2622 tgl@sss.pgh.pa.us 2288 : 464 : activeRIRs = lappend_oid(activeRIRs, RelationGetRelid(rel));
2289 : :
2290 : : /*
2291 : : * get_row_security_policies just passed back securityQuals
2292 : : * and/or withCheckOptions, and there were SubLinks, make sure
2293 : : * we lock any relations which are referenced.
2294 : : *
2295 : : * These locks would normally be acquired by the parser, but
2296 : : * securityQuals and withCheckOptions are added post-parsing.
2297 : : */
4041 sfrost@snowman.net 2298 : 464 : context.for_execute = true;
2299 : 464 : (void) acquireLocksOnSubLinks((Node *) securityQuals, &context);
2300 : 464 : (void) acquireLocksOnSubLinks((Node *) withCheckOptions,
2301 : : &context);
2302 : :
2303 : : /*
2304 : : * Now that we have the locks on anything added by
2305 : : * get_row_security_policies, fire any RIR rules for them.
2306 : : */
678 nathan@postgresql.or 2307 : 464 : fire_context.activeRIRs = activeRIRs;
2308 : 464 : fire_context.hasRowSecurity = false;
2309 : :
4138 bruce@momjian.us 2310 : 464 : expression_tree_walker((Node *) securityQuals,
2311 : : fireRIRonSubLink, &fire_context);
2312 : :
2313 : 420 : expression_tree_walker((Node *) withCheckOptions,
2314 : : fireRIRonSubLink, &fire_context);
2315 : :
2316 : : /*
2317 : : * We can ignore the value of fire_context.hasRowSecurity
2318 : : * since we only reach this code in cases where hasRowSecurity
2319 : : * is already true.
2320 : : */
678 nathan@postgresql.or 2321 [ - + ]: 416 : Assert(hasRowSecurity);
2322 : :
2622 tgl@sss.pgh.pa.us 2323 : 416 : activeRIRs = list_delete_last(activeRIRs);
2324 : : }
2325 : :
2326 : : /*
2327 : : * Add the new security barrier quals to the start of the RTE's
2328 : : * list so that they get applied before any existing barrier quals
2329 : : * (which would have come from a security-barrier view, and should
2330 : : * get lower priority than RLS conditions on the table itself).
2331 : : */
4169 sfrost@snowman.net 2332 : 4184 : rte->securityQuals = list_concat(securityQuals,
2333 : 2092 : rte->securityQuals);
2334 : :
2335 : 2092 : parsetree->withCheckOptions = list_concat(withCheckOptions,
3378 tgl@sss.pgh.pa.us 2336 : 2092 : parsetree->withCheckOptions);
2337 : : }
2338 : :
2339 : : /*
2340 : : * Make sure the query is marked correctly if row-level security
2341 : : * applies, or if the new quals had sublinks.
2342 : : */
4169 sfrost@snowman.net 2343 [ + + ]: 294899 : if (hasRowSecurity)
2344 : 2481 : parsetree->hasRowSecurity = true;
2345 [ + + ]: 294899 : if (hasSubLinks)
2346 : 416 : parsetree->hasSubLinks = true;
2347 : :
2799 andres@anarazel.de 2348 : 294899 : table_close(rel, NoLock);
2349 : : }
2350 : :
10215 bruce@momjian.us 2351 : 366857 : return parsetree;
2352 : : }
2353 : :
2354 : :
2355 : : /*
2356 : : * Modify the given query by adding 'AND rule_qual IS NOT TRUE' to its
2357 : : * qualification. This is used to generate suitable "else clauses" for
2358 : : * conditional INSTEAD rules. (Unfortunately we must use "x IS NOT TRUE",
2359 : : * not just "NOT x" which the planner is much smarter about, else we will
2360 : : * do the wrong thing when the qual evaluates to NULL.)
2361 : : *
2362 : : * The rule_qual may contain references to OLD or NEW. OLD references are
2363 : : * replaced by references to the specified rt_index (the relation that the
2364 : : * rule applies to). NEW references are only possible for INSERT and UPDATE
2365 : : * queries on the relation itself, and so they should be replaced by copies
2366 : : * of the related entries in the query's own targetlist.
2367 : : */
2368 : : static Query *
8736 tgl@sss.pgh.pa.us 2369 : 304 : CopyAndAddInvertedQual(Query *parsetree,
2370 : : Node *rule_qual,
2371 : : int rt_index,
2372 : : CmdType event)
2373 : : {
2374 : : /* Don't scribble on the passed qual (it's in the relcache!) */
3482 peter_e@gmx.net 2375 : 304 : Node *new_qual = copyObject(rule_qual);
2376 : : acquireLocksOnSubLinks_context context;
2377 : :
4581 tgl@sss.pgh.pa.us 2378 : 304 : context.for_execute = true;
2379 : :
2380 : : /*
2381 : : * In case there are subqueries in the qual, acquire necessary locks and
2382 : : * fix any deleted JOIN RTE entries. (This is somewhat redundant with
2383 : : * rewriteRuleAction, but not entirely ... consider restructuring so that
2384 : : * we only need to process the qual this way once.)
2385 : : */
2386 : 304 : (void) acquireLocksOnSubLinks(new_qual, &context);
2387 : :
2388 : : /* Fix references to OLD */
9420 2389 : 304 : ChangeVarNodes(new_qual, PRS2_OLD_VARNO, rt_index, 0);
2390 : : /* Fix references to NEW */
2391 [ + + + + ]: 304 : if (event == CMD_INSERT || event == CMD_UPDATE)
2392 : : {
152 rguo@postgresql.org 2393 : 296 : RangeTblEntry *rte = rt_fetch(rt_index, parsetree->rtable);
2394 : : Relation rel;
2395 : : List *gen_cols;
2396 : :
2397 : : /*
2398 : : * As in rewriteRuleAction, build entries for generated columns so
2399 : : * that new.gen_col in the rule qualification can be rewritten
2400 : : * correctly.
2401 : : */
2402 : 296 : rel = relation_open(rte->relid, NoLock);
2403 : 296 : gen_cols = get_generated_columns(rel, PRS2_NEW_VARNO, true);
2404 : 296 : relation_close(rel, NoLock);
2405 : :
2406 : : /*
2407 : : * The generated column expressions refer to new.attribute, so they
2408 : : * must be rewritten before they can be used as replacements.
2409 : : */
2410 : : gen_cols = (List *)
2411 [ + + ]: 296 : ReplaceVarsFromTargetList((Node *) gen_cols,
2412 : : PRS2_NEW_VARNO,
2413 : : 0,
2414 : : rte,
2415 : : parsetree->targetList,
2416 : : parsetree->resultRelation,
2417 : : (event == CMD_UPDATE) ?
2418 : : REPLACEVARS_CHANGE_VARNO :
2419 : : REPLACEVARS_SUBSTITUTE_NULL,
2420 : : rt_index,
2421 : : &parsetree->hasSubLinks);
2422 : :
5064 tgl@sss.pgh.pa.us 2423 [ + + ]: 592 : new_qual = ReplaceVarsFromTargetList(new_qual,
2424 : : PRS2_NEW_VARNO,
2425 : : 0,
2426 : : rte,
2427 : : list_concat(gen_cols,
152 rguo@postgresql.org 2428 : 296 : parsetree->targetList),
2429 : : parsetree->resultRelation,
2430 : : (event == CMD_UPDATE) ?
2431 : : REPLACEVARS_CHANGE_VARNO :
2432 : : REPLACEVARS_SUBSTITUTE_NULL,
2433 : : rt_index,
2434 : : &parsetree->hasSubLinks);
2435 : : }
2436 : : /* And attach the fixed qual */
7779 tgl@sss.pgh.pa.us 2437 : 304 : AddInvertedQual(parsetree, new_qual);
2438 : :
2439 : 304 : return parsetree;
2440 : : }
2441 : :
2442 : :
2443 : : /*
2444 : : * fireRules -
2445 : : * Iterate through rule locks applying rules.
2446 : : *
2447 : : * Input arguments:
2448 : : * parsetree - original query
2449 : : * rt_index - RT index of result relation in original query
2450 : : * event - type of rule event
2451 : : * locks - list of rules to fire
2452 : : * Output arguments:
2453 : : * *instead_flag - set true if any unqualified INSTEAD rule is found
2454 : : * (must be initialized to false)
2455 : : * *returning_flag - set true if we rewrite RETURNING clause in any rule
2456 : : * (must be initialized to false)
2457 : : * *qual_product - filled with modified original query if any qualified
2458 : : * INSTEAD rule is found (must be initialized to NULL)
2459 : : * Return value:
2460 : : * list of rule actions adjusted for use with this query
2461 : : *
2462 : : * Qualified INSTEAD rules generate their action with the qualification
2463 : : * condition added. They also generate a modified version of the original
2464 : : * query with the negated qualification added, so that it will run only for
2465 : : * rows that the qualified action doesn't act on. (If there are multiple
2466 : : * qualified INSTEAD rules, we AND all the negated quals onto a single
2467 : : * modified original query.) We won't execute the original, unmodified
2468 : : * query if we find either qualified or unqualified INSTEAD rules. If
2469 : : * we find both, the modified original query is discarded too.
2470 : : */
2471 : : static List *
10604 bruce@momjian.us 2472 : 57980 : fireRules(Query *parsetree,
2473 : : int rt_index,
2474 : : CmdType event,
2475 : : List *locks,
2476 : : bool *instead_flag,
2477 : : bool *returning_flag,
2478 : : Query **qual_product)
2479 : : {
2480 : 57980 : List *results = NIL;
2481 : : ListCell *l;
2482 : :
8152 neilc@samurai.com 2483 [ + + + + : 59048 : foreach(l, locks)
+ + ]
2484 : : {
2485 : 1088 : RewriteRule *rule_lock = (RewriteRule *) lfirst(l);
8737 tgl@sss.pgh.pa.us 2486 : 1088 : Node *event_qual = rule_lock->qual;
2487 : 1088 : List *actions = rule_lock->actions;
2488 : : QuerySource qsrc;
2489 : : ListCell *r;
2490 : :
2491 : : /* Determine correct QuerySource value for actions */
8742 2492 [ + + ]: 1088 : if (rule_lock->isInstead)
2493 : : {
2494 [ + + ]: 808 : if (event_qual != NULL)
2495 : 308 : qsrc = QSRC_QUAL_INSTEAD_RULE;
2496 : : else
2497 : : {
2498 : 500 : qsrc = QSRC_INSTEAD_RULE;
8448 bruce@momjian.us 2499 : 500 : *instead_flag = true; /* report unqualified INSTEAD */
2500 : : }
2501 : : }
2502 : : else
8742 tgl@sss.pgh.pa.us 2503 : 280 : qsrc = QSRC_NON_INSTEAD_RULE;
2504 : :
2505 [ + + ]: 1088 : if (qsrc == QSRC_QUAL_INSTEAD_RULE)
2506 : : {
2507 : : /*
2508 : : * If there are INSTEAD rules with qualifications, the original
2509 : : * query is still performed. But all the negated rule
2510 : : * qualifications of the INSTEAD rules are added so it does its
2511 : : * actions only in cases where the rule quals of all INSTEAD rules
2512 : : * are false. Think of it as the default action in a case. We save
2513 : : * this in *qual_product so RewriteQuery() can add it to the query
2514 : : * list after we mangled it up enough.
2515 : : *
2516 : : * If we have already found an unqualified INSTEAD rule, then
2517 : : * *qual_product won't be used, so don't bother building it.
2518 : : */
8448 bruce@momjian.us 2519 [ + + ]: 308 : if (!*instead_flag)
2520 : : {
8737 tgl@sss.pgh.pa.us 2521 [ + + ]: 304 : if (*qual_product == NULL)
7779 2522 : 248 : *qual_product = copyObject(parsetree);
8736 2523 : 304 : *qual_product = CopyAndAddInvertedQual(*qual_product,
2524 : : event_qual,
2525 : : rt_index,
2526 : : event);
2527 : : }
2528 : : }
2529 : :
2530 : : /* Now process the rule's actions and add them to the result list */
10605 bruce@momjian.us 2531 [ + - + + : 2192 : foreach(r, actions)
+ + ]
2532 : : {
10604 2533 : 1124 : Query *rule_action = lfirst(r);
2534 : :
10260 scrappy@hub.org 2535 [ + + ]: 1124 : if (rule_action->commandType == CMD_NOTHING)
2536 : 148 : continue;
2537 : :
9230 tgl@sss.pgh.pa.us 2538 : 976 : rule_action = rewriteRuleAction(parsetree, rule_action,
2539 : : event_qual, rt_index, event,
2540 : : returning_flag);
2541 : :
8742 2542 : 956 : rule_action->querySource = qsrc;
3378 2543 : 956 : rule_action->canSetTag = false; /* might change later */
2544 : :
9230 2545 : 956 : results = lappend(results, rule_action);
2546 : : }
2547 : : }
2548 : :
10605 bruce@momjian.us 2549 : 57960 : return results;
2550 : : }
2551 : :
2552 : :
2553 : : /*
2554 : : * get_view_query - get the Query from a view's _RETURN rule.
2555 : : *
2556 : : * Caller should have verified that the relation is a view, and therefore
2557 : : * we should find an ON SELECT action.
2558 : : *
2559 : : * Note that the pointer returned is into the relcache and therefore must
2560 : : * be treated as read-only to the caller and not modified or scribbled on.
2561 : : */
2562 : : Query *
5034 tgl@sss.pgh.pa.us 2563 : 3987 : get_view_query(Relation view)
2564 : : {
2565 : : int i;
2566 : :
2567 [ - + ]: 3987 : Assert(view->rd_rel->relkind == RELKIND_VIEW);
2568 : :
2569 [ + - ]: 3987 : for (i = 0; i < view->rd_rules->numLocks; i++)
2570 : : {
2571 : 3987 : RewriteRule *rule = view->rd_rules->rules[i];
2572 : :
2573 [ + - ]: 3987 : if (rule->event == CMD_SELECT)
2574 : : {
2575 : : /* A _RETURN rule should have only one action */
2576 [ - + ]: 3987 : if (list_length(rule->actions) != 1)
5034 tgl@sss.pgh.pa.us 2577 [ # # ]:UBC 0 : elog(ERROR, "invalid _RETURN rule action specification");
2578 : :
5034 tgl@sss.pgh.pa.us 2579 :CBC 3987 : return (Query *) linitial(rule->actions);
2580 : : }
2581 : : }
2582 : :
5034 tgl@sss.pgh.pa.us 2583 [ # # ]:UBC 0 : elog(ERROR, "failed to find _RETURN rule for view");
2584 : : return NULL; /* keep compiler quiet */
2585 : : }
2586 : :
2587 : :
2588 : : /*
2589 : : * view_has_instead_trigger - does view have an INSTEAD OF trigger for event?
2590 : : *
2591 : : * If it does, we don't want to treat it as auto-updatable. This test can't
2592 : : * be folded into view_query_is_auto_updatable because it's not an error
2593 : : * condition.
2594 : : *
2595 : : * For MERGE, this will return true if there is an INSTEAD OF trigger for
2596 : : * every action in mergeActionList, and false if there are any actions that
2597 : : * lack an INSTEAD OF trigger. If there are no data-modifying MERGE actions
2598 : : * (only DO NOTHING actions), true is returned so that the view is treated
2599 : : * as trigger-updatable, rather than erroring out if it's not auto-updatable.
2600 : : */
2601 : : bool
934 dean.a.rasheed@gmail 2602 :CBC 3708 : view_has_instead_trigger(Relation view, CmdType event, List *mergeActionList)
2603 : : {
5034 tgl@sss.pgh.pa.us 2604 : 3708 : TriggerDesc *trigDesc = view->trigdesc;
2605 : :
2606 [ + + + + : 3708 : switch (event)
- ]
2607 : : {
2608 : 1234 : case CMD_INSERT:
2609 [ + + + - ]: 1234 : if (trigDesc && trigDesc->trig_insert_instead_row)
2610 : 174 : return true;
2611 : 1060 : break;
2612 : 1368 : case CMD_UPDATE:
2613 [ + + + - ]: 1368 : if (trigDesc && trigDesc->trig_update_instead_row)
2614 : 210 : return true;
2615 : 1158 : break;
2616 : 406 : case CMD_DELETE:
2617 [ + + + - ]: 406 : if (trigDesc && trigDesc->trig_delete_instead_row)
2618 : 70 : return true;
2619 : 336 : break;
934 dean.a.rasheed@gmail 2620 : 700 : case CMD_MERGE:
2621 [ + - + + : 988 : foreach_node(MergeAction, action, mergeActionList)
+ + ]
2622 : : {
2623 [ + + + + : 780 : switch (action->commandType)
- ]
2624 : : {
2625 : 136 : case CMD_INSERT:
2626 [ + + + + ]: 136 : if (!trigDesc || !trigDesc->trig_insert_instead_row)
2627 : 596 : return false;
2628 : 56 : break;
2629 : 496 : case CMD_UPDATE:
2630 [ + + - + ]: 496 : if (!trigDesc || !trigDesc->trig_update_instead_row)
2631 : 424 : return false;
2632 : 72 : break;
2633 : 108 : case CMD_DELETE:
2634 [ + + + + ]: 108 : if (!trigDesc || !trigDesc->trig_delete_instead_row)
2635 : 92 : return false;
2636 : 16 : break;
2637 : 40 : case CMD_NOTHING:
2638 : : /* No trigger required */
2639 : 40 : break;
934 dean.a.rasheed@gmail 2640 :UBC 0 : default:
2641 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d", action->commandType);
2642 : : break;
2643 : : }
2644 : : }
934 dean.a.rasheed@gmail 2645 :CBC 104 : return true; /* no actions without an INSTEAD OF trigger */
5034 tgl@sss.pgh.pa.us 2646 :UBC 0 : default:
2647 [ # # ]: 0 : elog(ERROR, "unrecognized CmdType: %d", (int) event);
2648 : : break;
2649 : : }
5034 tgl@sss.pgh.pa.us 2650 :CBC 2554 : return false;
2651 : : }
2652 : :
2653 : :
2654 : : /*
2655 : : * view_col_is_auto_updatable - test whether the specified column of a view
2656 : : * is auto-updatable. Returns NULL (if the column can be updated) or a message
2657 : : * string giving the reason that it cannot be.
2658 : : *
2659 : : * The returned string has not been translated; if it is shown as an error
2660 : : * message, the caller should apply _() to translate it.
2661 : : *
2662 : : * Note that the checks performed here are local to this view. We do not check
2663 : : * whether the referenced column of the underlying base relation is updatable.
2664 : : */
2665 : : static const char *
4720 rhaas@postgresql.org 2666 : 9784 : view_col_is_auto_updatable(RangeTblRef *rtr, TargetEntry *tle)
2667 : : {
2668 : 9784 : Var *var = (Var *) tle->expr;
2669 : :
2670 : : /*
2671 : : * For now, the only updatable columns we support are those that are Vars
2672 : : * referring to user columns of the underlying base relation.
2673 : : *
2674 : : * The view targetlist may contain resjunk columns (e.g., a view defined
2675 : : * like "SELECT * FROM t ORDER BY a+b" is auto-updatable) but such columns
2676 : : * are not auto-updatable, and in fact should never appear in the outer
2677 : : * query's targetlist.
2678 : : */
2679 [ + + ]: 9784 : if (tle->resjunk)
2680 : 120 : return gettext_noop("Junk view columns are not updatable.");
2681 : :
2682 [ + + ]: 9664 : if (!IsA(var, Var) ||
2683 [ + - ]: 8684 : var->varno != rtr->rtindex ||
2684 [ - + ]: 8684 : var->varlevelsup != 0)
2685 : 980 : return gettext_noop("View columns that are not columns of their base relation are not updatable.");
2686 : :
2687 [ + + ]: 8684 : if (var->varattno < 0)
2688 : 268 : return gettext_noop("View columns that refer to system columns are not updatable.");
2689 : :
2690 [ - + ]: 8416 : if (var->varattno == 0)
4720 rhaas@postgresql.org 2691 :UBC 0 : return gettext_noop("View columns that return whole-row references are not updatable.");
2692 : :
4720 rhaas@postgresql.org 2693 :CBC 8416 : return NULL; /* the view column is updatable */
2694 : : }
2695 : :
2696 : :
2697 : : /*
2698 : : * view_query_is_auto_updatable - test whether the specified view definition
2699 : : * represents an auto-updatable view. Returns NULL (if the view can be updated)
2700 : : * or a message string giving the reason that it cannot be.
2701 : : *
2702 : : * The returned string has not been translated; if it is shown as an error
2703 : : * message, the caller should apply _() to translate it.
2704 : : *
2705 : : * If check_cols is true, the view is required to have at least one updatable
2706 : : * column (necessary for INSERT/UPDATE). Otherwise the view's columns are not
2707 : : * checked for updatability. See also view_cols_are_auto_updatable.
2708 : : *
2709 : : * Note that the checks performed here are only based on the view definition.
2710 : : * We do not check whether any base relations referred to by the view are
2711 : : * updatable.
2712 : : */
2713 : : const char *
4544 sfrost@snowman.net 2714 : 3830 : view_query_is_auto_updatable(Query *viewquery, bool check_cols)
2715 : : {
2716 : : RangeTblRef *rtr;
2717 : : RangeTblEntry *base_rte;
2718 : :
2719 : : /*----------
2720 : : * Check if the view is simply updatable. According to SQL-92 this means:
2721 : : * - No DISTINCT clause.
2722 : : * - Each TLE is a column reference, and each column appears at most once.
2723 : : * - FROM contains exactly one base relation.
2724 : : * - No GROUP BY or HAVING clauses.
2725 : : * - No set operations (UNION, INTERSECT or EXCEPT).
2726 : : * - No sub-queries in the WHERE clause that reference the target table.
2727 : : *
2728 : : * We ignore that last restriction since it would be complex to enforce
2729 : : * and there isn't any actual benefit to disallowing sub-queries. (The
2730 : : * semantic issues that the standard is presumably concerned about don't
2731 : : * arise in Postgres, since any such sub-query will not see any updates
2732 : : * executed by the outer query anyway, thanks to MVCC snapshotting.)
2733 : : *
2734 : : * We also relax the second restriction by supporting part of SQL:1999
2735 : : * feature T111, which allows for a mix of updatable and non-updatable
2736 : : * columns, provided that an INSERT or UPDATE doesn't attempt to assign to
2737 : : * a non-updatable column.
2738 : : *
2739 : : * In addition we impose these constraints, involving features that are
2740 : : * not part of SQL-92:
2741 : : * - No CTEs (WITH clauses).
2742 : : * - No OFFSET or LIMIT clauses (this matches a SQL:2008 restriction).
2743 : : * - No system columns (including whole-row references) in the tlist.
2744 : : * - No window functions in the tlist.
2745 : : * - No set-returning functions in the tlist.
2746 : : *
2747 : : * Note that we do these checks without recursively expanding the view.
2748 : : * If the base relation is a view, we'll recursively deal with it later.
2749 : : *----------
2750 : : */
5034 tgl@sss.pgh.pa.us 2751 [ + + ]: 3830 : if (viewquery->distinctClause != NIL)
2752 : 48 : return gettext_noop("Views containing DISTINCT are not automatically updatable.");
2753 : :
4145 andres@anarazel.de 2754 [ + + - + ]: 3782 : if (viewquery->groupClause != NIL || viewquery->groupingSets)
5034 tgl@sss.pgh.pa.us 2755 : 24 : return gettext_noop("Views containing GROUP BY are not automatically updatable.");
2756 : :
2757 [ + + ]: 3758 : if (viewquery->havingQual != NULL)
2758 : 20 : return gettext_noop("Views containing HAVING are not automatically updatable.");
2759 : :
2760 [ + + ]: 3738 : if (viewquery->setOperations != NULL)
4907 peter_e@gmx.net 2761 : 24 : return gettext_noop("Views containing UNION, INTERSECT, or EXCEPT are not automatically updatable.");
2762 : :
5034 tgl@sss.pgh.pa.us 2763 [ + + ]: 3714 : if (viewquery->cteList != NIL)
2764 : 24 : return gettext_noop("Views containing WITH are not automatically updatable.");
2765 : :
2766 [ + + + + ]: 3690 : if (viewquery->limitOffset != NULL || viewquery->limitCount != NULL)
2767 : 384 : return gettext_noop("Views containing LIMIT or OFFSET are not automatically updatable.");
2768 : :
2769 : : /*
2770 : : * We must not allow window functions or set returning functions in the
2771 : : * targetlist. Otherwise we might end up inserting them into the quals of
2772 : : * the main query. We must also check for aggregates in the targetlist in
2773 : : * case they appear without a GROUP BY.
2774 : : *
2775 : : * These restrictions ensure that each row of the view corresponds to a
2776 : : * unique row in the underlying base relation.
2777 : : */
4720 rhaas@postgresql.org 2778 [ + + ]: 3306 : if (viewquery->hasAggs)
4405 peter_e@gmx.net 2779 : 20 : return gettext_noop("Views that return aggregate functions are not automatically updatable.");
2780 : :
4720 rhaas@postgresql.org 2781 [ + + ]: 3286 : if (viewquery->hasWindowFuncs)
4405 peter_e@gmx.net 2782 : 24 : return gettext_noop("Views that return window functions are not automatically updatable.");
2783 : :
3659 tgl@sss.pgh.pa.us 2784 [ + + ]: 3262 : if (viewquery->hasTargetSRFs)
4720 rhaas@postgresql.org 2785 : 28 : return gettext_noop("Views that return set-returning functions are not automatically updatable.");
2786 : :
2787 : : /*
2788 : : * The view query should select from a single base relation, which must be
2789 : : * a table or another view.
2790 : : */
5034 tgl@sss.pgh.pa.us 2791 [ + + ]: 3234 : if (list_length(viewquery->jointree->fromlist) != 1)
2792 : 44 : return gettext_noop("Views that do not select from a single table or view are not automatically updatable.");
2793 : :
2794 : 3190 : rtr = (RangeTblRef *) linitial(viewquery->jointree->fromlist);
2795 [ - + ]: 3190 : if (!IsA(rtr, RangeTblRef))
5034 tgl@sss.pgh.pa.us 2796 :UBC 0 : return gettext_noop("Views that do not select from a single table or view are not automatically updatable.");
2797 : :
5034 tgl@sss.pgh.pa.us 2798 :CBC 3190 : base_rte = rt_fetch(rtr->rtindex, viewquery->rtable);
2799 [ + + ]: 3190 : if (base_rte->rtekind != RTE_RELATION ||
2800 [ + + ]: 3114 : (base_rte->relkind != RELKIND_RELATION &&
4848 2801 [ + + ]: 1197 : base_rte->relkind != RELKIND_FOREIGN_TABLE &&
3526 rhaas@postgresql.org 2802 [ + + ]: 1186 : base_rte->relkind != RELKIND_VIEW &&
2803 [ + + ]: 166 : base_rte->relkind != RELKIND_PARTITIONED_TABLE))
5034 tgl@sss.pgh.pa.us 2804 : 104 : return gettext_noop("Views that do not select from a single table or view are not automatically updatable.");
2805 : :
4146 simon@2ndQuadrant.co 2806 [ + + ]: 3086 : if (base_rte->tablesample)
2807 : 4 : return gettext_noop("Views containing TABLESAMPLE are not automatically updatable.");
2808 : :
2809 : : /*
2810 : : * Check that the view has at least one updatable column. This is required
2811 : : * for INSERT/UPDATE but not for DELETE.
2812 : : */
4720 rhaas@postgresql.org 2813 [ + + ]: 3082 : if (check_cols)
2814 : : {
2815 : : ListCell *cell;
2816 : : bool found;
2817 : :
2818 : 2126 : found = false;
2819 [ + - + - : 2250 : foreach(cell, viewquery->targetList)
+ - ]
2820 : : {
2821 : 2250 : TargetEntry *tle = (TargetEntry *) lfirst(cell);
2822 : :
2823 [ + + ]: 2250 : if (view_col_is_auto_updatable(rtr, tle) == NULL)
2824 : : {
2825 : 2126 : found = true;
2826 : 2126 : break;
2827 : : }
2828 : : }
2829 : :
2830 [ - + ]: 2126 : if (!found)
4720 rhaas@postgresql.org 2831 :UBC 0 : return gettext_noop("Views that have no updatable columns are not automatically updatable.");
2832 : : }
2833 : :
4720 rhaas@postgresql.org 2834 :CBC 3082 : return NULL; /* the view is updatable */
2835 : : }
2836 : :
2837 : :
2838 : : /*
2839 : : * view_cols_are_auto_updatable - test whether all of the required columns of
2840 : : * an auto-updatable view are actually updatable. Returns NULL (if all the
2841 : : * required columns can be updated) or a message string giving the reason that
2842 : : * they cannot be.
2843 : : *
2844 : : * The returned string has not been translated; if it is shown as an error
2845 : : * message, the caller should apply _() to translate it.
2846 : : *
2847 : : * This should be used for INSERT/UPDATE to ensure that we don't attempt to
2848 : : * assign to any non-updatable columns.
2849 : : *
2850 : : * Additionally it may be used to retrieve the set of updatable columns in the
2851 : : * view, or if one or more of the required columns is not updatable, the name
2852 : : * of the first offending non-updatable column.
2853 : : *
2854 : : * The caller must have already verified that this is an auto-updatable view
2855 : : * using view_query_is_auto_updatable.
2856 : : *
2857 : : * Note that the checks performed here are only based on the view definition.
2858 : : * We do not check whether the referenced columns of the base relation are
2859 : : * updatable.
2860 : : */
2861 : : static const char *
2862 : 2726 : view_cols_are_auto_updatable(Query *viewquery,
2863 : : Bitmapset *required_cols,
2864 : : Bitmapset **updatable_cols,
2865 : : char **non_updatable_col)
2866 : : {
2867 : : RangeTblRef *rtr;
2868 : : AttrNumber col;
2869 : : ListCell *cell;
2870 : :
2871 : : /*
2872 : : * The caller should have verified that this view is auto-updatable and so
2873 : : * there should be a single base relation.
2874 : : */
2875 [ - + ]: 2726 : Assert(list_length(viewquery->jointree->fromlist) == 1);
3450 tgl@sss.pgh.pa.us 2876 : 2726 : rtr = linitial_node(RangeTblRef, viewquery->jointree->fromlist);
2877 : :
2878 : : /* Initialize the optional return values */
4720 rhaas@postgresql.org 2879 [ + + ]: 2726 : if (updatable_cols != NULL)
2880 : 700 : *updatable_cols = NULL;
2881 [ + + ]: 2726 : if (non_updatable_col != NULL)
2882 : 2026 : *non_updatable_col = NULL;
2883 : :
2884 : : /* Test each view column for updatability */
2885 : 2726 : col = -FirstLowInvalidHeapAttributeNumber;
2886 [ + - + + : 10180 : foreach(cell, viewquery->targetList)
+ + ]
2887 : : {
2888 : 7534 : TargetEntry *tle = (TargetEntry *) lfirst(cell);
2889 : : const char *col_update_detail;
2890 : :
2891 : 7534 : col++;
2892 : 7534 : col_update_detail = view_col_is_auto_updatable(rtr, tle);
2893 : :
2894 [ + + ]: 7534 : if (col_update_detail == NULL)
2895 : : {
2896 : : /* The column is updatable */
2897 [ + + ]: 6290 : if (updatable_cols != NULL)
2898 : 1424 : *updatable_cols = bms_add_member(*updatable_cols, col);
2899 : : }
2900 [ + + ]: 1244 : else if (bms_is_member(col, required_cols))
2901 : : {
2902 : : /* The required column is not updatable */
2903 [ + - ]: 80 : if (non_updatable_col != NULL)
2904 : 80 : *non_updatable_col = tle->resname;
2905 : 80 : return col_update_detail;
2906 : : }
2907 : : }
2908 : :
4520 bruce@momjian.us 2909 : 2646 : return NULL; /* all the required view columns are updatable */
2910 : : }
2911 : :
2912 : :
2913 : : /*
2914 : : * relation_is_updatable - determine which update events the specified
2915 : : * relation supports.
2916 : : *
2917 : : * Note that views may contain a mix of updatable and non-updatable columns.
2918 : : * For a view to support INSERT/UPDATE it must have at least one updatable
2919 : : * column, but there is no such restriction for DELETE. If include_cols is
2920 : : * non-NULL, then only the specified columns are considered when testing for
2921 : : * updatability.
2922 : : *
2923 : : * Unlike the preceding functions, this does recurse to look at a view's
2924 : : * base relations, so it needs to detect recursion. To do that, we pass
2925 : : * a list of currently-considered outer relations. External callers need
2926 : : * only pass NIL.
2927 : : *
2928 : : * This is used for the information_schema views, which have separate concepts
2929 : : * of "updatable" and "trigger updatable". A relation is "updatable" if it
2930 : : * can be updated without the need for triggers (either because it has a
2931 : : * suitable RULE, or because it is simple enough to be automatically updated).
2932 : : * A relation is "trigger updatable" if it has a suitable INSTEAD OF trigger.
2933 : : * The SQL standard regards this as not necessarily updatable, presumably
2934 : : * because there is no way of knowing what the trigger will actually do.
2935 : : * The information_schema views therefore call this function with
2936 : : * include_triggers = false. However, other callers might only care whether
2937 : : * data-modifying SQL will work, so they can pass include_triggers = true
2938 : : * to have trigger updatability included in the result.
2939 : : *
2940 : : * The return value is a bitmask of rule event numbers indicating which of
2941 : : * the INSERT, UPDATE and DELETE operations are supported. (We do it this way
2942 : : * so that we can test for UPDATE plus DELETE support in a single call.)
2943 : : */
2944 : : int
4720 rhaas@postgresql.org 2945 : 1408 : relation_is_updatable(Oid reloid,
2946 : : List *outer_reloids,
2947 : : bool include_triggers,
2948 : : Bitmapset *include_cols)
2949 : : {
4848 tgl@sss.pgh.pa.us 2950 : 1408 : int events = 0;
2951 : : Relation rel;
2952 : : RuleLock *rulelocks;
2953 : :
2954 : : #define ALL_EVENTS ((1 << CMD_INSERT) | (1 << CMD_UPDATE) | (1 << CMD_DELETE))
2955 : :
2956 : : /* Since this function recurses, it could be driven to stack overflow */
2495 2957 : 1408 : check_stack_depth();
2958 : :
5034 2959 : 1408 : rel = try_relation_open(reloid, AccessShareLock);
2960 : :
2961 : : /*
2962 : : * If the relation doesn't exist, return zero rather than throwing an
2963 : : * error. This is helpful since scanning an information_schema view under
2964 : : * MVCC rules can result in referencing rels that have actually been
2965 : : * deleted already.
2966 : : */
2967 [ - + ]: 1408 : if (rel == NULL)
4848 tgl@sss.pgh.pa.us 2968 :UBC 0 : return 0;
2969 : :
2970 : : /* If we detect a recursive view, report that it is not updatable */
2495 tgl@sss.pgh.pa.us 2971 [ - + ]:CBC 1408 : if (list_member_oid(outer_reloids, RelationGetRelid(rel)))
2972 : : {
2495 tgl@sss.pgh.pa.us 2973 :UBC 0 : relation_close(rel, AccessShareLock);
2974 : 0 : return 0;
2975 : : }
2976 : :
2977 : : /* If the relation is a table, it is always updatable */
3386 dean.a.rasheed@gmail 2978 [ + - ]:CBC 1408 : if (rel->rd_rel->relkind == RELKIND_RELATION ||
2979 [ + + ]: 1408 : rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
2980 : : {
4848 tgl@sss.pgh.pa.us 2981 : 12 : relation_close(rel, AccessShareLock);
2982 : 12 : return ALL_EVENTS;
2983 : : }
2984 : :
2985 : : /* Look for unconditional DO INSTEAD rules, and note supported events */
5034 2986 : 1396 : rulelocks = rel->rd_rules;
2987 [ + - ]: 1396 : if (rulelocks != NULL)
2988 : : {
2989 : : int i;
2990 : :
2991 [ + + ]: 3040 : for (i = 0; i < rulelocks->numLocks; i++)
2992 : : {
2993 [ + + ]: 1644 : if (rulelocks->rules[i]->isInstead &&
2994 [ + - ]: 1636 : rulelocks->rules[i]->qual == NULL)
2995 : : {
4848 2996 : 1636 : events |= ((1 << rulelocks->rules[i]->event) & ALL_EVENTS);
2997 : : }
2998 : : }
2999 : :
3000 : : /* If we have rules for all events, we're done */
3001 [ + + ]: 1396 : if (events == ALL_EVENTS)
3002 : : {
5034 3003 : 40 : relation_close(rel, AccessShareLock);
4848 3004 : 40 : return events;
3005 : : }
3006 : : }
3007 : :
3008 : : /* Similarly look for INSTEAD OF triggers, if they are to be included */
3009 [ - + ]: 1356 : if (include_triggers)
3010 : : {
4848 tgl@sss.pgh.pa.us 3011 :UBC 0 : TriggerDesc *trigDesc = rel->trigdesc;
3012 : :
3013 [ # # ]: 0 : if (trigDesc)
3014 : : {
3015 [ # # ]: 0 : if (trigDesc->trig_insert_instead_row)
3016 : 0 : events |= (1 << CMD_INSERT);
3017 [ # # ]: 0 : if (trigDesc->trig_update_instead_row)
3018 : 0 : events |= (1 << CMD_UPDATE);
3019 [ # # ]: 0 : if (trigDesc->trig_delete_instead_row)
3020 : 0 : events |= (1 << CMD_DELETE);
3021 : :
3022 : : /* If we have triggers for all events, we're done */
3023 [ # # ]: 0 : if (events == ALL_EVENTS)
3024 : : {
3025 : 0 : relation_close(rel, AccessShareLock);
3026 : 0 : return events;
3027 : : }
3028 : : }
3029 : : }
3030 : :
3031 : : /* If this is a foreign table, check which update events it supports */
4848 tgl@sss.pgh.pa.us 3032 [ - + ]:CBC 1356 : if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
3033 : : {
4848 tgl@sss.pgh.pa.us 3034 :UBC 0 : FdwRoutine *fdwroutine = GetFdwRoutineForRelation(rel, false);
3035 : :
3036 [ # # ]: 0 : if (fdwroutine->IsForeignRelUpdatable != NULL)
3037 : 0 : events |= fdwroutine->IsForeignRelUpdatable(rel);
3038 : : else
3039 : : {
3040 : : /* Assume presence of executor functions is sufficient */
3041 [ # # ]: 0 : if (fdwroutine->ExecForeignInsert != NULL)
3042 : 0 : events |= (1 << CMD_INSERT);
3043 [ # # ]: 0 : if (fdwroutine->ExecForeignUpdate != NULL)
3044 : 0 : events |= (1 << CMD_UPDATE);
3045 [ # # ]: 0 : if (fdwroutine->ExecForeignDelete != NULL)
3046 : 0 : events |= (1 << CMD_DELETE);
3047 : : }
3048 : :
3049 : 0 : relation_close(rel, AccessShareLock);
3050 : 0 : return events;
3051 : : }
3052 : :
3053 : : /* Check if this is an automatically updatable view */
4720 rhaas@postgresql.org 3054 [ + - ]:CBC 1356 : if (rel->rd_rel->relkind == RELKIND_VIEW)
3055 : : {
3056 : 1356 : Query *viewquery = get_view_query(rel);
3057 : :
4544 sfrost@snowman.net 3058 [ + + ]: 1356 : if (view_query_is_auto_updatable(viewquery, false) == NULL)
3059 : : {
3060 : : Bitmapset *updatable_cols;
3061 : : int auto_events;
3062 : : RangeTblRef *rtr;
3063 : : RangeTblEntry *base_rte;
3064 : : Oid baseoid;
3065 : :
3066 : : /*
3067 : : * Determine which of the view's columns are updatable. If there
3068 : : * are none within the set of columns we are looking at, then the
3069 : : * view doesn't support INSERT/UPDATE, but it may still support
3070 : : * DELETE.
3071 : : */
4720 rhaas@postgresql.org 3072 : 700 : view_cols_are_auto_updatable(viewquery, NULL,
3073 : : &updatable_cols, NULL);
3074 : :
3075 [ + + ]: 700 : if (include_cols != NULL)
3076 : 384 : updatable_cols = bms_int_members(updatable_cols, include_cols);
3077 : :
3078 [ + + ]: 700 : if (bms_is_empty(updatable_cols))
3378 tgl@sss.pgh.pa.us 3079 : 100 : auto_events = (1 << CMD_DELETE); /* May support DELETE */
3080 : : else
3081 : 600 : auto_events = ALL_EVENTS; /* May support all events */
3082 : :
3083 : : /*
3084 : : * The base relation must also support these update commands.
3085 : : * Tables are always updatable, but for any other kind of base
3086 : : * relation we must do a recursive check limited to the columns
3087 : : * referenced by the locally updatable columns in this view.
3088 : : */
4720 rhaas@postgresql.org 3089 : 700 : rtr = (RangeTblRef *) linitial(viewquery->jointree->fromlist);
3090 : 700 : base_rte = rt_fetch(rtr->rtindex, viewquery->rtable);
3091 [ - + ]: 700 : Assert(base_rte->rtekind == RTE_RELATION);
3092 : :
3386 dean.a.rasheed@gmail 3093 [ + + ]: 700 : if (base_rte->relkind != RELKIND_RELATION &&
3094 [ + + ]: 388 : base_rte->relkind != RELKIND_PARTITIONED_TABLE)
3095 : : {
4720 rhaas@postgresql.org 3096 : 368 : baseoid = base_rte->relid;
2495 tgl@sss.pgh.pa.us 3097 : 368 : outer_reloids = lappend_oid(outer_reloids,
3098 : : RelationGetRelid(rel));
4720 rhaas@postgresql.org 3099 : 368 : include_cols = adjust_view_column_set(updatable_cols,
3100 : : viewquery->targetList);
3101 : 368 : auto_events &= relation_is_updatable(baseoid,
3102 : : outer_reloids,
3103 : : include_triggers,
3104 : : include_cols);
2495 tgl@sss.pgh.pa.us 3105 : 368 : outer_reloids = list_delete_last(outer_reloids);
3106 : : }
4720 rhaas@postgresql.org 3107 : 700 : events |= auto_events;
3108 : : }
3109 : : }
3110 : :
3111 : : /* If we reach here, the relation may support some update commands */
5034 tgl@sss.pgh.pa.us 3112 : 1356 : relation_close(rel, AccessShareLock);
4848 3113 : 1356 : return events;
3114 : : }
3115 : :
3116 : :
3117 : : /*
3118 : : * adjust_view_column_set - map a set of column numbers according to targetlist
3119 : : *
3120 : : * This is used with simply-updatable views to map column-permissions sets for
3121 : : * the view columns onto the matching columns in the underlying base relation.
3122 : : * Relevant entries in the targetlist must be plain Vars of the underlying
3123 : : * relation (as per the checks above in view_query_is_auto_updatable).
3124 : : */
3125 : : static Bitmapset *
5034 3126 : 4764 : adjust_view_column_set(Bitmapset *cols, List *targetlist)
3127 : : {
3128 : 4764 : Bitmapset *result = NULL;
3129 : : int col;
3130 : :
4314 3131 : 4764 : col = -1;
3132 [ + + ]: 8264 : while ((col = bms_next_member(cols, col)) >= 0)
3133 : : {
3134 : : /* bit numbers are offset by FirstLowInvalidHeapAttributeNumber */
5034 3135 : 3500 : AttrNumber attno = col + FirstLowInvalidHeapAttributeNumber;
3136 : :
3137 [ - + ]: 3500 : if (attno == InvalidAttrNumber)
3138 : : {
3139 : : /*
3140 : : * There's a whole-row reference to the view. For permissions
3141 : : * purposes, treat it as a reference to each column available from
3142 : : * the view. (We should *not* convert this to a whole-row
3143 : : * reference to the base relation, since the view may not touch
3144 : : * all columns of the base relation.)
3145 : : */
3146 : : ListCell *lc;
3147 : :
5034 tgl@sss.pgh.pa.us 3148 [ # # # # :UBC 0 : foreach(lc, targetlist)
# # ]
3149 : : {
3450 3150 : 0 : TargetEntry *tle = lfirst_node(TargetEntry, lc);
3151 : : Var *var;
3152 : :
5034 3153 [ # # ]: 0 : if (tle->resjunk)
3154 : 0 : continue;
3498 peter_e@gmx.net 3155 : 0 : var = castNode(Var, tle->expr);
5034 tgl@sss.pgh.pa.us 3156 : 0 : result = bms_add_member(result,
3378 3157 : 0 : var->varattno - FirstLowInvalidHeapAttributeNumber);
3158 : : }
3159 : : }
3160 : : else
3161 : : {
3162 : : /*
3163 : : * Views do not have system columns, so we do not expect to see
3164 : : * any other system attnos here. If we do find one, the error
3165 : : * case will apply.
3166 : : */
5034 tgl@sss.pgh.pa.us 3167 :CBC 3500 : TargetEntry *tle = get_tle_by_resno(targetlist, attno);
3168 : :
3169 [ + - + - : 3500 : if (tle != NULL && !tle->resjunk && IsA(tle->expr, Var))
+ - ]
3170 : 3500 : {
3171 : 3500 : Var *var = (Var *) tle->expr;
3172 : :
3173 : 3500 : result = bms_add_member(result,
3378 3174 : 3500 : var->varattno - FirstLowInvalidHeapAttributeNumber);
3175 : : }
3176 : : else
5034 tgl@sss.pgh.pa.us 3177 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3178 : : attno);
3179 : : }
3180 : : }
3181 : :
5034 tgl@sss.pgh.pa.us 3182 :CBC 4764 : return result;
3183 : : }
3184 : :
3185 : :
3186 : : /*
3187 : : * error_view_not_updatable -
3188 : : * Report an error due to an attempt to update a non-updatable view.
3189 : : *
3190 : : * Generally this is expected to be called from the rewriter, with suitable
3191 : : * error detail explaining why the view is not updatable. Note, however, that
3192 : : * the executor also performs a just-in-case check that the target view is
3193 : : * updatable. That check is expected to never fail, but if it does, it will
3194 : : * call this function with NULL error detail --- see CheckValidResultRel().
3195 : : *
3196 : : * Note: for MERGE, at least one of the actions in mergeActionList is expected
3197 : : * to lack a suitable INSTEAD OF trigger --- see view_has_instead_trigger().
3198 : : */
3199 : : void
934 dean.a.rasheed@gmail 3200 : 104 : error_view_not_updatable(Relation view,
3201 : : CmdType command,
3202 : : List *mergeActionList,
3203 : : const char *detail)
3204 : : {
3205 : 104 : TriggerDesc *trigDesc = view->trigdesc;
3206 : :
3207 [ + + + + : 104 : switch (command)
- ]
3208 : : {
3209 : 16 : case CMD_INSERT:
3210 [ + - + - ]: 16 : ereport(ERROR,
3211 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3212 : : errmsg("cannot insert into view \"%s\"",
3213 : : RelationGetRelationName(view)),
3214 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3215 : : errhint("To enable inserting into the view, provide an INSTEAD OF INSERT trigger or an unconditional ON INSERT DO INSTEAD rule."));
3216 : : break;
3217 : 36 : case CMD_UPDATE:
3218 [ + - + - ]: 36 : ereport(ERROR,
3219 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3220 : : errmsg("cannot update view \"%s\"",
3221 : : RelationGetRelationName(view)),
3222 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3223 : : errhint("To enable updating the view, provide an INSTEAD OF UPDATE trigger or an unconditional ON UPDATE DO INSTEAD rule."));
3224 : : break;
3225 : 32 : case CMD_DELETE:
3226 [ + - + - ]: 32 : ereport(ERROR,
3227 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3228 : : errmsg("cannot delete from view \"%s\"",
3229 : : RelationGetRelationName(view)),
3230 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3231 : : errhint("To enable deleting from the view, provide an INSTEAD OF DELETE trigger or an unconditional ON DELETE DO INSTEAD rule."));
3232 : : break;
3233 : 20 : case CMD_MERGE:
3234 : :
3235 : : /*
3236 : : * Note that the error hints here differ from above, since MERGE
3237 : : * doesn't support rules.
3238 : : */
3239 [ + - + - : 24 : foreach_node(MergeAction, action, mergeActionList)
+ - ]
3240 : : {
3241 [ + + + - : 24 : switch (action->commandType)
- ]
3242 : : {
3243 : 8 : case CMD_INSERT:
3244 [ + + + - ]: 8 : if (!trigDesc || !trigDesc->trig_insert_instead_row)
3245 [ + - + - ]: 8 : ereport(ERROR,
3246 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3247 : : errmsg("cannot insert into view \"%s\"",
3248 : : RelationGetRelationName(view)),
3249 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3250 : : errhint("To enable inserting into the view using MERGE, provide an INSTEAD OF INSERT trigger."));
934 dean.a.rasheed@gmail 3251 :UBC 0 : break;
934 dean.a.rasheed@gmail 3252 :CBC 8 : case CMD_UPDATE:
3253 [ + + - + ]: 8 : if (!trigDesc || !trigDesc->trig_update_instead_row)
3254 [ + - + - ]: 4 : ereport(ERROR,
3255 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3256 : : errmsg("cannot update view \"%s\"",
3257 : : RelationGetRelationName(view)),
3258 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3259 : : errhint("To enable updating the view using MERGE, provide an INSTEAD OF UPDATE trigger."));
3260 : 4 : break;
3261 : 8 : case CMD_DELETE:
3262 [ + + + - ]: 8 : if (!trigDesc || !trigDesc->trig_delete_instead_row)
3263 [ + - + - ]: 8 : ereport(ERROR,
3264 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3265 : : errmsg("cannot delete from view \"%s\"",
3266 : : RelationGetRelationName(view)),
3267 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3268 : : errhint("To enable deleting from the view using MERGE, provide an INSTEAD OF DELETE trigger."));
934 dean.a.rasheed@gmail 3269 :UBC 0 : break;
3270 : 0 : case CMD_NOTHING:
3271 : 0 : break;
3272 : 0 : default:
3273 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d", action->commandType);
3274 : : break;
3275 : : }
3276 : : }
3277 : 0 : break;
3278 : 0 : default:
3279 [ # # ]: 0 : elog(ERROR, "unrecognized CmdType: %d", (int) command);
3280 : : break;
3281 : : }
3282 : 0 : }
3283 : :
3284 : :
3285 : : /*
3286 : : * rewriteTargetView -
3287 : : * Attempt to rewrite a query where the target relation is a view, so that
3288 : : * the view's base relation becomes the target relation.
3289 : : *
3290 : : * Note that the base relation here may itself be a view, which may or may not
3291 : : * have INSTEAD OF triggers or rules to handle the update. That is handled by
3292 : : * the recursion in RewriteQuery.
3293 : : */
3294 : : static Query *
5034 tgl@sss.pgh.pa.us 3295 :CBC 2378 : rewriteTargetView(Query *parsetree, Relation view)
3296 : : {
3297 : : Query *viewquery;
3298 : : bool insert_or_update;
3299 : : const char *auto_update_detail;
3300 : : RangeTblRef *rtr;
3301 : : int base_rt_index;
3302 : : int new_rt_index;
3303 : : RangeTblEntry *base_rte;
3304 : : RangeTblEntry *view_rte;
3305 : : RangeTblEntry *new_rte;
3306 : : RTEPermissionInfo *base_perminfo;
3307 : : RTEPermissionInfo *view_perminfo;
3308 : : RTEPermissionInfo *new_perminfo;
3309 : : Relation base_rel;
3310 : : List *view_targetlist;
3311 : : ListCell *lc;
3312 : :
3313 : : /*
3314 : : * Get the Query from the view's ON SELECT rule. We're going to munge the
3315 : : * Query to change the view's base relation into the target relation,
3316 : : * along with various other changes along the way, so we need to make a
3317 : : * copy of it (get_view_query() returns a pointer into the relcache, so we
3318 : : * have to treat it as read-only).
3319 : : */
3926 sfrost@snowman.net 3320 : 2378 : viewquery = copyObject(get_view_query(view));
3321 : :
3322 : : /* Locate RTE and perminfo describing the view in the outer query */
792 tgl@sss.pgh.pa.us 3323 : 2378 : view_rte = rt_fetch(parsetree->resultRelation, parsetree->rtable);
3324 : 2378 : view_perminfo = getRTEPermissionInfo(parsetree->rteperminfos, view_rte);
3325 : :
3326 : : /*
3327 : : * Are we doing INSERT/UPDATE, or MERGE containing INSERT/UPDATE? If so,
3328 : : * various additional checks on the view columns need to be applied, and
3329 : : * any view CHECK OPTIONs need to be enforced.
3330 : : */
934 dean.a.rasheed@gmail 3331 : 2378 : insert_or_update =
3332 [ + + ]: 3900 : (parsetree->commandType == CMD_INSERT ||
3333 [ + + ]: 1522 : parsetree->commandType == CMD_UPDATE);
3334 : :
3335 [ + + ]: 2378 : if (parsetree->commandType == CMD_MERGE)
3336 : : {
3337 [ + - + + : 1284 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3338 : : {
3339 [ + + ]: 628 : if (action->commandType == CMD_INSERT ||
3340 [ + + ]: 556 : action->commandType == CMD_UPDATE)
3341 : : {
3342 : 536 : insert_or_update = true;
5034 tgl@sss.pgh.pa.us 3343 : 536 : break;
3344 : : }
3345 : : }
3346 : : }
3347 : :
3348 : : /* Check if the expansion of non-system views are restricted */
776 msawada@postgresql.o 3349 [ + + + - : 2378 : if (unlikely((restrict_nonsystem_relation_kind & RESTRICT_RELKIND_VIEW) != 0 &&
+ + ]
3350 : : RelationGetRelid(view) >= FirstNormalObjectId))
3351 [ + - ]: 4 : ereport(ERROR,
3352 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3353 : : errmsg("access to non-system view \"%s\" is restricted",
3354 : : RelationGetRelationName(view))));
3355 : :
3356 : : /*
3357 : : * The view must be updatable, else fail.
3358 : : *
3359 : : * If we are doing INSERT/UPDATE (or MERGE containing INSERT/UPDATE), we
3360 : : * also check that there is at least one updatable column.
3361 : : */
3362 : : auto_update_detail =
934 dean.a.rasheed@gmail 3363 : 2374 : view_query_is_auto_updatable(viewquery, insert_or_update);
3364 : :
3365 [ + + ]: 2374 : if (auto_update_detail)
3366 : 92 : error_view_not_updatable(view,
3367 : : parsetree->commandType,
3368 : : parsetree->mergeActionList,
3369 : : auto_update_detail);
3370 : :
3371 : : /*
3372 : : * For INSERT/UPDATE (or MERGE containing INSERT/UPDATE) the modified
3373 : : * columns must all be updatable.
3374 : : */
3375 [ + + ]: 2282 : if (insert_or_update)
3376 : : {
3377 : : Bitmapset *modified_cols;
3378 : : char *non_updatable_col;
3379 : :
3380 : : /*
3381 : : * Compute the set of modified columns as those listed in the result
3382 : : * RTE's insertedCols and/or updatedCols sets plus those that are
3383 : : * targets of the query's targetlist(s). We must consider the query's
3384 : : * targetlist because rewriteTargetListIU may have added additional
3385 : : * targetlist entries for view defaults, and these must also be
3386 : : * updatable. But rewriteTargetListIU can also remove entries if they
3387 : : * are DEFAULT markers and the column's default is NULL, so
3388 : : * considering only the targetlist would also be wrong.
3389 : : */
792 tgl@sss.pgh.pa.us 3390 : 2026 : modified_cols = bms_union(view_perminfo->insertedCols,
3391 : 2026 : view_perminfo->updatedCols);
3392 : :
4720 rhaas@postgresql.org 3393 [ + + + + : 4302 : foreach(lc, parsetree->targetList)
+ + ]
3394 : : {
3395 : 2276 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3396 : :
3397 [ + - ]: 2276 : if (!tle->resjunk)
3398 : 2276 : modified_cols = bms_add_member(modified_cols,
3378 tgl@sss.pgh.pa.us 3399 : 2276 : tle->resno - FirstLowInvalidHeapAttributeNumber);
3400 : : }
3401 : :
4153 andres@anarazel.de 3402 [ + + ]: 2026 : if (parsetree->onConflict)
3403 : : {
3404 [ + + + + : 280 : foreach(lc, parsetree->onConflict->onConflictSet)
+ + ]
3405 : : {
3406 : 108 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3407 : :
3408 [ + - ]: 108 : if (!tle->resjunk)
3409 : 108 : modified_cols = bms_add_member(modified_cols,
3378 tgl@sss.pgh.pa.us 3410 : 108 : tle->resno - FirstLowInvalidHeapAttributeNumber);
3411 : : }
3412 : : }
3413 : :
934 dean.a.rasheed@gmail 3414 [ + + + + : 4704 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3415 : : {
3416 [ + + ]: 652 : if (action->commandType == CMD_INSERT ||
3417 [ + + ]: 512 : action->commandType == CMD_UPDATE)
3418 : : {
3419 [ + - + + : 1964 : foreach_node(TargetEntry, tle, action->targetList)
+ + ]
3420 : : {
3421 [ + - ]: 756 : if (!tle->resjunk)
3422 : 756 : modified_cols = bms_add_member(modified_cols,
3423 : 756 : tle->resno - FirstLowInvalidHeapAttributeNumber);
3424 : : }
3425 : : }
3426 : : }
3427 : :
4720 rhaas@postgresql.org 3428 : 2026 : auto_update_detail = view_cols_are_auto_updatable(viewquery,
3429 : : modified_cols,
3430 : : NULL,
3431 : : &non_updatable_col);
3432 [ + + ]: 2026 : if (auto_update_detail)
3433 : : {
3434 : : /*
3435 : : * This is a different error, caused by an attempt to update a
3436 : : * non-updatable column in an otherwise updatable view.
3437 : : */
3438 [ + + + - ]: 80 : switch (parsetree->commandType)
3439 : : {
3440 : 48 : case CMD_INSERT:
3441 [ + - ]: 48 : ereport(ERROR,
3442 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3443 : : errmsg("cannot insert into column \"%s\" of view \"%s\"",
3444 : : non_updatable_col,
3445 : : RelationGetRelationName(view)),
3446 : : errdetail_internal("%s", _(auto_update_detail))));
3447 : : break;
3448 : 28 : case CMD_UPDATE:
3449 [ + - ]: 28 : ereport(ERROR,
3450 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3451 : : errmsg("cannot update column \"%s\" of view \"%s\"",
3452 : : non_updatable_col,
3453 : : RelationGetRelationName(view)),
3454 : : errdetail_internal("%s", _(auto_update_detail))));
3455 : : break;
934 dean.a.rasheed@gmail 3456 : 4 : case CMD_MERGE:
3457 [ + - ]: 4 : ereport(ERROR,
3458 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3459 : : errmsg("cannot merge into column \"%s\" of view \"%s\"",
3460 : : non_updatable_col,
3461 : : RelationGetRelationName(view)),
3462 : : errdetail_internal("%s", _(auto_update_detail))));
3463 : : break;
4720 rhaas@postgresql.org 3464 :UBC 0 : default:
3465 [ # # ]: 0 : elog(ERROR, "unrecognized CmdType: %d",
3466 : : (int) parsetree->commandType);
3467 : : break;
3468 : : }
3469 : : }
3470 : : }
3471 : :
3472 : : /*
3473 : : * For MERGE, there must not be any INSTEAD OF triggers on an otherwise
3474 : : * updatable view. The caller already checked that there isn't a full set
3475 : : * of INSTEAD OF triggers, so this is to guard against having a partial
3476 : : * set (mixing auto-update and trigger-update actions in a single command
3477 : : * isn't supported).
3478 : : */
934 dean.a.rasheed@gmail 3479 [ + + ]:CBC 2202 : if (parsetree->commandType == CMD_MERGE)
3480 : : {
3481 [ + - + + : 1832 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3482 : : {
3483 [ + - + + ]: 1392 : if (action->commandType != CMD_NOTHING &&
3484 : 696 : view_has_instead_trigger(view, action->commandType, NIL))
3485 [ + - ]: 4 : ereport(ERROR,
3486 : : errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3487 : : errmsg("cannot merge into view \"%s\"",
3488 : : RelationGetRelationName(view)),
3489 : : errdetail("MERGE is not supported for views with INSTEAD OF triggers for some actions but not all."),
3490 : : errhint("To enable merging into the view, either provide a full set of INSTEAD OF triggers or drop the existing INSTEAD OF triggers."));
3491 : : }
3492 : : }
3493 : :
3494 : : /*
3495 : : * If we get here, view_query_is_auto_updatable() has verified that the
3496 : : * view contains a single base relation.
3497 : : */
5034 tgl@sss.pgh.pa.us 3498 [ - + ]: 2198 : Assert(list_length(viewquery->jointree->fromlist) == 1);
3450 3499 : 2198 : rtr = linitial_node(RangeTblRef, viewquery->jointree->fromlist);
3500 : :
5034 3501 : 2198 : base_rt_index = rtr->rtindex;
3502 : 2198 : base_rte = rt_fetch(base_rt_index, viewquery->rtable);
3503 [ - + ]: 2198 : Assert(base_rte->rtekind == RTE_RELATION);
1384 alvherre@alvh.no-ip. 3504 : 2198 : base_perminfo = getRTEPermissionInfo(viewquery->rteperminfos, base_rte);
3505 : :
3506 : : /*
3507 : : * Up to now, the base relation hasn't been touched at all in our query.
3508 : : * We need to acquire lock on it before we try to do anything with it.
3509 : : * (The subsequent recursive call of RewriteQuery will suppose that we
3510 : : * already have the right lock!) Since it will become the query target
3511 : : * relation, RowExclusiveLock is always the right thing.
3512 : : */
193 peter@eisentraut.org 3513 : 2198 : base_rel = relation_open(base_rte->relid, RowExclusiveLock);
3514 : :
3515 : : /*
3516 : : * While we have the relation open, update the RTE's relkind, just in case
3517 : : * it changed since this view was made (cf. AcquireRewriteLocks).
3518 : : */
5034 tgl@sss.pgh.pa.us 3519 : 2198 : base_rte->relkind = base_rel->rd_rel->relkind;
3520 : :
3521 : : /*
3522 : : * If the view query contains any sublink subqueries then we need to also
3523 : : * acquire locks on any relations they refer to. We know that there won't
3524 : : * be any subqueries in the range table or CTEs, so we can skip those, as
3525 : : * in AcquireRewriteLocks.
3526 : : */
4030 sfrost@snowman.net 3527 [ + + ]: 2198 : if (viewquery->hasSubLinks)
3528 : : {
3529 : : acquireLocksOnSubLinks_context context;
3530 : :
3531 : 172 : context.for_execute = true;
3532 : 172 : query_tree_walker(viewquery, acquireLocksOnSubLinks, &context,
3533 : : QTW_IGNORE_RC_SUBQUERIES);
3534 : : }
3535 : :
3536 : : /*
3537 : : * Create a new target RTE describing the base relation, and add it to the
3538 : : * outer query's rangetable. (What's happening in the next few steps is
3539 : : * very much like what the planner would do to "pull up" the view into the
3540 : : * outer query. Perhaps someday we should refactor things enough so that
3541 : : * we can share code with the planner.)
3542 : : *
3543 : : * Be sure to set rellockmode to the correct thing for the target table.
3544 : : * Since we copied the whole viewquery above, we can just scribble on
3545 : : * base_rte instead of copying it.
3546 : : */
2912 tgl@sss.pgh.pa.us 3547 : 2198 : new_rte = base_rte;
3548 : 2198 : new_rte->rellockmode = RowExclusiveLock;
3549 : :
5034 3550 : 2198 : parsetree->rtable = lappend(parsetree->rtable, new_rte);
3551 : 2198 : new_rt_index = list_length(parsetree->rtable);
3552 : :
3553 : : /*
3554 : : * INSERTs never inherit. For UPDATE/DELETE/MERGE, we use the view
3555 : : * query's inheritance flag for the base relation.
3556 : : */
4827 3557 [ + + ]: 2198 : if (parsetree->commandType == CMD_INSERT)
3558 : 792 : new_rte->inh = false;
3559 : :
3560 : : /*
3561 : : * Adjust the view's targetlist Vars to reference the new target RTE, ie
3562 : : * make their varnos be new_rt_index instead of base_rt_index. There can
3563 : : * be no Vars for other rels in the tlist, so this is sufficient to pull
3564 : : * up the tlist expressions for use in the outer query. The tlist will
3565 : : * provide the replacement expressions used by ReplaceVarsFromTargetList
3566 : : * below.
3567 : : */
3926 sfrost@snowman.net 3568 : 2198 : view_targetlist = viewquery->targetList;
3569 : :
5034 tgl@sss.pgh.pa.us 3570 : 2198 : ChangeVarNodes((Node *) view_targetlist,
3571 : : base_rt_index,
3572 : : new_rt_index,
3573 : : 0);
3574 : :
3575 : : /*
3576 : : * If the view has "security_invoker" set, mark the new target relation
3577 : : * for the permissions checks that we want to enforce against the query
3578 : : * caller. Otherwise we want to enforce them against the view owner.
3579 : : *
3580 : : * At the relation level, require the same INSERT/UPDATE/DELETE
3581 : : * permissions that the query caller needs against the view. We drop the
3582 : : * ACL_SELECT bit that is presumably in new_perminfo->requiredPerms
3583 : : * initially.
3584 : : *
3585 : : * Note: the original view's RTEPermissionInfo remains in the query's
3586 : : * rteperminfos so that the executor still performs appropriate
3587 : : * permissions checks for the query caller's use of the view.
3588 : : *
3589 : : * Disregard the perminfo in viewquery->rteperminfos that the base_rte
3590 : : * would currently be pointing at, because we'd like it to point now to a
3591 : : * new one that will be filled below. Must set perminfoindex to 0 to not
3592 : : * trip over the Assert in addRTEPermissionInfo().
3593 : : */
1384 alvherre@alvh.no-ip. 3594 : 2198 : new_rte->perminfoindex = 0;
3595 : 2198 : new_perminfo = addRTEPermissionInfo(&parsetree->rteperminfos, new_rte);
1643 dean.a.rasheed@gmail 3596 [ - + + + : 2198 : if (RelationHasSecurityInvoker(view))
+ + ]
1384 alvherre@alvh.no-ip. 3597 : 324 : new_perminfo->checkAsUser = InvalidOid;
3598 : : else
3599 : 1874 : new_perminfo->checkAsUser = view->rd_rel->relowner;
3600 : 2198 : new_perminfo->requiredPerms = view_perminfo->requiredPerms;
3601 : :
3602 : : /*
3603 : : * Now for the per-column permissions bits.
3604 : : *
3605 : : * Initially, new_perminfo (base_perminfo) contains selectedCols
3606 : : * permission check bits for all base-rel columns referenced by the view,
3607 : : * but since the view is a SELECT query its insertedCols/updatedCols is
3608 : : * empty. We set insertedCols and updatedCols to include all the columns
3609 : : * the outer query is trying to modify, adjusting the column numbers as
3610 : : * needed. But we leave selectedCols as-is, so the view owner must have
3611 : : * read permission for all columns used in the view definition, even if
3612 : : * some of them are not read by the outer query. We could try to limit
3613 : : * selectedCols to only columns used in the transformed query, but that
3614 : : * does not correspond to what happens in ordinary SELECT usage of a view:
3615 : : * all referenced columns must have read permission, even if optimization
3616 : : * finds that some of them can be discarded during query transformation.
3617 : : * The flattening we're doing here is an optional optimization, too. (If
3618 : : * you are unpersuaded and want to change this, note that applying
3619 : : * adjust_view_column_set to view_perminfo->selectedCols is clearly *not*
3620 : : * the right answer, since that neglects base-rel columns used in the
3621 : : * view's WHERE quals.)
3622 : : *
3623 : : * This step needs the modified view targetlist, so we have to do things
3624 : : * in this order.
3625 : : */
3626 [ + - - + ]: 2198 : Assert(bms_is_empty(new_perminfo->insertedCols) &&
3627 : : bms_is_empty(new_perminfo->updatedCols));
3628 : :
3629 : 2198 : new_perminfo->selectedCols = base_perminfo->selectedCols;
3630 : :
3631 : 2198 : new_perminfo->insertedCols =
3632 : 2198 : adjust_view_column_set(view_perminfo->insertedCols, view_targetlist);
3633 : :
3634 : 2198 : new_perminfo->updatedCols =
3635 : 2198 : adjust_view_column_set(view_perminfo->updatedCols, view_targetlist);
3636 : :
3637 : : /*
3638 : : * Move any security barrier quals from the view RTE onto the new target
3639 : : * RTE. Any such quals should now apply to the new target RTE and will
3640 : : * not reference the original view RTE in the rewritten query.
3641 : : */
4544 sfrost@snowman.net 3642 : 2198 : new_rte->securityQuals = view_rte->securityQuals;
3643 : 2198 : view_rte->securityQuals = NIL;
3644 : :
3645 : : /*
3646 : : * Now update all Vars in the outer query that reference the view to
3647 : : * reference the appropriate column of the base relation instead.
3648 : : */
3649 : : parsetree = (Query *)
5034 tgl@sss.pgh.pa.us 3650 : 2198 : ReplaceVarsFromTargetList((Node *) parsetree,
3651 : : parsetree->resultRelation,
3652 : : 0,
3653 : : view_rte,
3654 : : view_targetlist,
3655 : : new_rt_index,
3656 : : REPLACEVARS_REPORT_ERROR,
3657 : : 0,
3658 : : NULL);
3659 : :
3660 : : /*
3661 : : * Update all other RTI references in the query that point to the view
3662 : : * (for example, parsetree->resultRelation itself) to point to the new
3663 : : * base relation instead. Vars will not be affected since none of them
3664 : : * reference parsetree->resultRelation any longer.
3665 : : */
3666 : 2198 : ChangeVarNodes((Node *) parsetree,
3667 : : parsetree->resultRelation,
3668 : : new_rt_index,
3669 : : 0);
3670 [ - + ]: 2198 : Assert(parsetree->resultRelation == new_rt_index);
3671 : :
3672 : : /*
3673 : : * For INSERT/UPDATE we must also update resnos in the targetlist to refer
3674 : : * to columns of the base relation, since those indicate the target
3675 : : * columns to be affected. Similarly, for MERGE we must update the resnos
3676 : : * in the merge action targetlists of any INSERT/UPDATE actions.
3677 : : *
3678 : : * Note that this destroys the resno ordering of the targetlists, but that
3679 : : * will be fixed when we recurse through RewriteQuery, which will invoke
3680 : : * rewriteTargetListIU again on the updated targetlists.
3681 : : */
3682 [ + + ]: 2198 : if (parsetree->commandType != CMD_DELETE)
3683 : : {
3684 [ + + + + : 4122 : foreach(lc, parsetree->targetList)
+ + ]
3685 : : {
3686 : 2124 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3687 : : TargetEntry *view_tle;
3688 : :
3689 [ - + ]: 2124 : if (tle->resjunk)
5034 tgl@sss.pgh.pa.us 3690 :UBC 0 : continue;
3691 : :
5034 tgl@sss.pgh.pa.us 3692 :CBC 2124 : view_tle = get_tle_by_resno(view_targetlist, tle->resno);
3693 [ + - + - : 2124 : if (view_tle != NULL && !view_tle->resjunk && IsA(view_tle->expr, Var))
+ - ]
3694 : 2124 : tle->resno = ((Var *) view_tle->expr)->varattno;
3695 : : else
5034 tgl@sss.pgh.pa.us 3696 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3697 : : tle->resno);
3698 : : }
3699 : :
934 dean.a.rasheed@gmail 3700 [ + + + + :CBC 4688 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3701 : : {
3702 [ + + ]: 692 : if (action->commandType == CMD_INSERT ||
3703 [ + + ]: 560 : action->commandType == CMD_UPDATE)
3704 : : {
3705 [ + - + + : 1904 : foreach_node(TargetEntry, tle, action->targetList)
+ + ]
3706 : : {
3707 : : TargetEntry *view_tle;
3708 : :
3709 [ - + ]: 728 : if (tle->resjunk)
934 dean.a.rasheed@gmail 3710 :UBC 0 : continue;
3711 : :
934 dean.a.rasheed@gmail 3712 :CBC 728 : view_tle = get_tle_by_resno(view_targetlist, tle->resno);
3713 [ + - + - : 728 : if (view_tle != NULL && !view_tle->resjunk && IsA(view_tle->expr, Var))
+ - ]
3714 : 728 : tle->resno = ((Var *) view_tle->expr)->varattno;
3715 : : else
934 dean.a.rasheed@gmail 3716 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3717 : : tle->resno);
3718 : : }
3719 : : }
3720 : : }
3721 : : }
3722 : :
3723 : : /*
3724 : : * For INSERT .. ON CONFLICT .. DO SELECT/UPDATE, we must also update
3725 : : * assorted stuff in the onConflict data structure.
3726 : : */
2969 tgl@sss.pgh.pa.us 3727 [ + + ]:CBC 2198 : if (parsetree->onConflict &&
220 dean.a.rasheed@gmail 3728 [ + + ]: 164 : (parsetree->onConflict->action == ONCONFLICT_UPDATE ||
3729 [ + + ]: 64 : parsetree->onConflict->action == ONCONFLICT_SELECT))
3730 : : {
3731 : : Index old_exclRelIndex,
3732 : : new_exclRelIndex;
3733 : : ParseNamespaceItem *new_exclNSItem;
3734 : : RangeTblEntry *new_exclRte;
3735 : : List *tmp_tlist;
3736 : :
3737 : : /*
3738 : : * For ON CONFLICT DO UPDATE, update the resnos in the auxiliary
3739 : : * UPDATE targetlist to refer to columns of the base relation.
3740 : : */
2969 tgl@sss.pgh.pa.us 3741 [ + + + + : 248 : foreach(lc, parsetree->onConflict->onConflictSet)
+ + ]
3742 : : {
3743 : 100 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3744 : : TargetEntry *view_tle;
3745 : :
3746 [ - + ]: 100 : if (tle->resjunk)
2969 tgl@sss.pgh.pa.us 3747 :UBC 0 : continue;
3748 : :
2969 tgl@sss.pgh.pa.us 3749 :CBC 100 : view_tle = get_tle_by_resno(view_targetlist, tle->resno);
3750 [ + - + - : 100 : if (view_tle != NULL && !view_tle->resjunk && IsA(view_tle->expr, Var))
+ - ]
3751 : 100 : tle->resno = ((Var *) view_tle->expr)->varattno;
3752 : : else
2969 tgl@sss.pgh.pa.us 3753 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3754 : : tle->resno);
3755 : : }
3756 : :
3757 : : /*
3758 : : * Create a new RTE for the EXCLUDED pseudo-relation, using the
3759 : : * query's new base rel (which may well have a different column list
3760 : : * from the view, hence we need a new column alias list). This should
3761 : : * match transformOnConflictClause. In particular, note that the
3762 : : * relkind is set to composite to signal that we're not dealing with
3763 : : * an actual relation.
3764 : : */
2969 tgl@sss.pgh.pa.us 3765 :CBC 148 : old_exclRelIndex = parsetree->onConflict->exclRelIndex;
3766 : :
2453 3767 : 148 : new_exclNSItem = addRangeTableEntryForRelation(make_parsestate(NULL),
3768 : : base_rel,
3769 : : RowExclusiveLock,
3770 : : makeAlias("excluded", NIL),
3771 : : false, false);
3772 : 148 : new_exclRte = new_exclNSItem->p_rte;
2969 3773 : 148 : new_exclRte->relkind = RELKIND_COMPOSITE_TYPE;
3774 : : /* Ignore the RTEPermissionInfo that would've been added. */
1384 alvherre@alvh.no-ip. 3775 : 148 : new_exclRte->perminfoindex = 0;
3776 : :
2969 tgl@sss.pgh.pa.us 3777 : 148 : parsetree->rtable = lappend(parsetree->rtable, new_exclRte);
3778 : 296 : new_exclRelIndex = parsetree->onConflict->exclRelIndex =
3779 : 148 : list_length(parsetree->rtable);
3780 : :
3781 : : /*
3782 : : * Replace the targetlist for the EXCLUDED pseudo-relation with a new
3783 : : * one, representing the columns from the new base relation.
3784 : : */
3785 : 296 : parsetree->onConflict->exclRelTlist =
3786 : 148 : BuildOnConflictExcludedTargetlist(base_rel, new_exclRelIndex);
3787 : :
3788 : : /*
3789 : : * Update all Vars in the ON CONFLICT clause that refer to the old
3790 : : * EXCLUDED pseudo-relation. We want to use the column mappings
3791 : : * defined in the view targetlist, but we need the outputs to refer to
3792 : : * the new EXCLUDED pseudo-relation rather than the new target RTE.
3793 : : * Also notice that "EXCLUDED.*" will be expanded using the view's
3794 : : * rowtype, which seems correct.
3795 : : */
3796 : 148 : tmp_tlist = copyObject(view_targetlist);
3797 : :
3798 : 148 : ChangeVarNodes((Node *) tmp_tlist, new_rt_index,
3799 : : new_exclRelIndex, 0);
3800 : :
3801 : 148 : parsetree->onConflict = (OnConflictExpr *)
3802 : 148 : ReplaceVarsFromTargetList((Node *) parsetree->onConflict,
3803 : : old_exclRelIndex,
3804 : : 0,
3805 : : view_rte,
3806 : : tmp_tlist,
3807 : : new_rt_index,
3808 : : REPLACEVARS_REPORT_ERROR,
3809 : : 0,
3810 : : &parsetree->hasSubLinks);
3811 : : }
3812 : :
3813 : : /*
3814 : : * For UPDATE/DELETE/MERGE, pull up any WHERE quals from the view. We
3815 : : * know that any Vars in the quals must reference the one base relation,
3816 : : * so we need only adjust their varnos to reference the new target (just
3817 : : * the same as we did with the view targetlist).
3818 : : *
3819 : : * If it's a security-barrier view, its WHERE quals must be applied before
3820 : : * quals from the outer query, so we attach them to the RTE as security
3821 : : * barrier quals rather than adding them to the main WHERE clause.
3822 : : *
3823 : : * For INSERT, the view's quals can be ignored in the main query.
3824 : : */
5034 3825 [ + + ]: 2198 : if (parsetree->commandType != CMD_INSERT &&
3826 [ + + ]: 1406 : viewquery->jointree->quals != NULL)
3827 : : {
3926 sfrost@snowman.net 3828 : 502 : Node *viewqual = (Node *) viewquery->jointree->quals;
3829 : :
3830 : : /*
3831 : : * Even though we copied viewquery already at the top of this
3832 : : * function, we must duplicate the viewqual again here, because we may
3833 : : * need to use the quals again below for a WithCheckOption clause.
3834 : : */
3918 tgl@sss.pgh.pa.us 3835 : 502 : viewqual = copyObject(viewqual);
3836 : :
5034 3837 : 502 : ChangeVarNodes(viewqual, base_rt_index, new_rt_index, 0);
3838 : :
4544 sfrost@snowman.net 3839 [ - + + + : 502 : if (RelationIsSecurityView(view))
+ + ]
3840 : : {
3841 : : /*
3842 : : * The view's quals go in front of existing barrier quals: those
3843 : : * would have come from an outer level of security-barrier view,
3844 : : * and so must get evaluated later.
3845 : : *
3846 : : * Note: the parsetree has been mutated, so the new_rte pointer is
3847 : : * stale and needs to be re-computed.
3848 : : */
3849 : 156 : new_rte = rt_fetch(new_rt_index, parsetree->rtable);
3850 : 156 : new_rte->securityQuals = lcons(viewqual, new_rte->securityQuals);
3851 : :
3852 : : /*
3853 : : * Do not set parsetree->hasRowSecurity, because these aren't RLS
3854 : : * conditions (they aren't affected by enabling/disabling RLS).
3855 : : */
3856 : :
3857 : : /*
3858 : : * Make sure that the query is marked correctly if the added qual
3859 : : * has sublinks.
3860 : : */
3861 [ + + ]: 156 : if (!parsetree->hasSubLinks)
3862 : 140 : parsetree->hasSubLinks = checkExprHasSubLink(viewqual);
3863 : : }
3864 : : else
292 peter@eisentraut.org 3865 : 346 : AddQual(parsetree, viewqual);
3866 : : }
3867 : :
3868 : : /*
3869 : : * For INSERT/UPDATE (or MERGE containing INSERT/UPDATE), if the view has
3870 : : * the WITH CHECK OPTION, or any parent view specified WITH CASCADED CHECK
3871 : : * OPTION, add the quals from the view to the query's withCheckOptions
3872 : : * list.
3873 : : */
5 3874 [ + + ]: 2198 : if (insert_or_update)
3875 : : {
4812 sfrost@snowman.net 3876 [ - + + + : 1942 : bool has_wco = RelationHasCheckOption(view);
+ + ]
3877 [ - + + + : 1942 : bool cascaded = RelationHasCascadedCheckOption(view);
+ + ]
3878 : :
3879 : : /*
3880 : : * If the parent view has a cascaded check option, treat this view as
3881 : : * if it also had a cascaded check option.
3882 : : *
3883 : : * New WithCheckOptions are added to the start of the list, so if
3884 : : * there is a cascaded check option, it will be the first item in the
3885 : : * list.
3886 : : */
3887 [ + + ]: 1942 : if (parsetree->withCheckOptions != NIL)
3888 : : {
3889 : 76 : WithCheckOption *parent_wco =
1220 tgl@sss.pgh.pa.us 3890 : 76 : (WithCheckOption *) linitial(parsetree->withCheckOptions);
3891 : :
4812 sfrost@snowman.net 3892 [ + + ]: 76 : if (parent_wco->cascaded)
3893 : : {
3894 : 60 : has_wco = true;
3895 : 60 : cascaded = true;
3896 : : }
3897 : : }
3898 : :
3899 : : /*
3900 : : * Add the new WithCheckOption to the start of the list, so that
3901 : : * checks on inner views are run before checks on outer views, as
3902 : : * required by the SQL standard.
3903 : : *
3904 : : * If the new check is CASCADED, we need to add it even if this view
3905 : : * has no quals, since there may be quals on child views. A LOCAL
3906 : : * check can be omitted if this view has no quals.
3907 : : */
3908 [ + + + + : 1942 : if (has_wco && (cascaded || viewquery->jointree->quals != NULL))
+ - ]
3909 : : {
3910 : : WithCheckOption *wco;
3911 : :
3912 : 430 : wco = makeNode(WithCheckOption);
4167 3913 : 430 : wco->kind = WCO_VIEW_CHECK;
3914 : 430 : wco->relname = pstrdup(RelationGetRelationName(view));
4023 3915 : 430 : wco->polname = NULL;
4812 3916 : 430 : wco->qual = NULL;
3917 : 430 : wco->cascaded = cascaded;
3918 : :
3919 : 430 : parsetree->withCheckOptions = lcons(wco,
3920 : : parsetree->withCheckOptions);
3921 : :
3922 [ + + ]: 430 : if (viewquery->jointree->quals != NULL)
3923 : : {
3926 3924 : 390 : wco->qual = (Node *) viewquery->jointree->quals;
4812 3925 : 390 : ChangeVarNodes(wco->qual, base_rt_index, new_rt_index, 0);
3926 : :
3927 : : /*
3928 : : * For INSERT, make sure that the query is marked correctly if
3929 : : * the added qual has sublinks. This can be skipped for
3930 : : * UPDATE/MERGE, since the same qual will have already been
3931 : : * added above, and the check will already have been done.
3932 : : */
3933 [ + + ]: 390 : if (!parsetree->hasSubLinks &&
934 dean.a.rasheed@gmail 3934 [ + + ]: 326 : parsetree->commandType == CMD_INSERT)
4812 sfrost@snowman.net 3935 : 204 : parsetree->hasSubLinks = checkExprHasSubLink(wco->qual);
3936 : : }
3937 : : }
3938 : : }
3939 : :
2799 andres@anarazel.de 3940 : 2198 : table_close(base_rel, NoLock);
3941 : :
5034 tgl@sss.pgh.pa.us 3942 : 2198 : return parsetree;
3943 : : }
3944 : :
3945 : :
3946 : : /*
3947 : : * RewriteQuery -
3948 : : * rewrites the query and apply the rules again on the queries rewritten
3949 : : *
3950 : : * rewrite_events is a list of open query-rewrite actions, so we can detect
3951 : : * infinite recursion.
3952 : : *
3953 : : * orig_rt_length is the length of the originating query's rtable, for product
3954 : : * queries created by fireRules(), and 0 otherwise. This is used to skip any
3955 : : * already-processed VALUES RTEs from the original query.
3956 : : *
3957 : : * num_ctes_processed is the number of CTEs at the end of the query's cteList
3958 : : * that have already been rewritten, and must not be rewritten again.
3959 : : */
3960 : : static List *
295 dean.a.rasheed@gmail 3961 : 284999 : RewriteQuery(Query *parsetree, List *rewrite_events, int orig_rt_length,
3962 : : int num_ctes_processed)
3963 : : {
8608 tgl@sss.pgh.pa.us 3964 : 284999 : CmdType event = parsetree->commandType;
3965 : 284999 : bool instead = false;
7323 3966 : 284999 : bool returning = false;
4153 andres@anarazel.de 3967 : 284999 : bool updatableview = false;
8608 tgl@sss.pgh.pa.us 3968 : 284999 : Query *qual_product = NULL;
3969 : 284999 : List *rewritten = NIL;
3970 : : ListCell *lc1;
3971 : :
3972 : : /*
3973 : : * First, recursively process any insert/update/delete/merge statements in
3974 : : * WITH clauses. (We have to do this first because the WITH clauses may
3975 : : * get copied into rule actions below.)
3976 : : *
3977 : : * Any new WITH clauses from rule actions are processed when we recurse
3978 : : * into product queries below. However, when recursing, we must take care
3979 : : * to avoid rewriting a CTE query more than once (because expanding
3980 : : * generated columns in the targetlist more than once would fail). Since
3981 : : * new CTEs from product queries are added to the start of the list (see
3982 : : * rewriteRuleAction), we just skip the last num_ctes_processed items.
3983 : : */
5584 3984 [ + + + + : 287335 : foreach(lc1, parsetree->cteList)
+ + ]
3985 : : {
3450 3986 : 2384 : CommonTableExpr *cte = lfirst_node(CommonTableExpr, lc1);
3498 peter_e@gmx.net 3987 : 2384 : Query *ctequery = castNode(Query, cte->ctequery);
295 dean.a.rasheed@gmail 3988 : 2384 : int i = foreach_current_index(lc1);
3989 : : List *newstuff;
3990 : :
3991 : : /* Skip already-processed CTEs at the end of the list */
3992 [ + + ]: 2384 : if (i >= list_length(parsetree->cteList) - num_ctes_processed)
3993 : 28 : break;
3994 : :
5584 tgl@sss.pgh.pa.us 3995 [ + + ]: 2356 : if (ctequery->commandType == CMD_SELECT)
3996 : 2114 : continue;
3997 : :
295 dean.a.rasheed@gmail 3998 : 242 : newstuff = RewriteQuery(ctequery, rewrite_events, 0, 0);
3999 : :
4000 : : /*
4001 : : * Currently we can only handle unconditional, single-statement DO
4002 : : * INSTEAD rules correctly; we have to get exactly one non-utility
4003 : : * Query out of the rewrite operation to stuff back into the CTE node.
4004 : : */
5584 tgl@sss.pgh.pa.us 4005 [ + + ]: 242 : if (list_length(newstuff) == 1)
4006 : : {
4007 : : /* Must check it's not a utility command */
3450 4008 : 226 : ctequery = linitial_node(Query, newstuff);
1899 4009 [ + - ]: 226 : if (!(ctequery->commandType == CMD_SELECT ||
4010 [ + + ]: 226 : ctequery->commandType == CMD_UPDATE ||
4011 [ + + ]: 169 : ctequery->commandType == CMD_INSERT ||
917 dean.a.rasheed@gmail 4012 [ + + ]: 54 : ctequery->commandType == CMD_DELETE ||
4013 [ + + ]: 23 : ctequery->commandType == CMD_MERGE))
4014 : : {
4015 : : /*
4016 : : * Currently it could only be NOTIFY; this error message will
4017 : : * need work if we ever allow other utility commands in rules.
4018 : : */
1899 tgl@sss.pgh.pa.us 4019 [ + - ]: 4 : ereport(ERROR,
4020 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4021 : : errmsg("DO INSTEAD NOTIFY rules are not supported for data-modifying statements in WITH")));
4022 : : }
4023 : : /* WITH queries should never be canSetTag */
5584 4024 [ - + ]: 222 : Assert(!ctequery->canSetTag);
4025 : : /* Push the single Query back into the CTE node */
4026 : 222 : cte->ctequery = (Node *) ctequery;
4027 : : }
4028 [ + + ]: 16 : else if (newstuff == NIL)
4029 : : {
4030 [ + - ]: 4 : ereport(ERROR,
4031 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4032 : : errmsg("DO INSTEAD NOTHING rules are not supported for data-modifying statements in WITH")));
4033 : : }
4034 : : else
4035 : : {
4036 : : ListCell *lc2;
4037 : :
4038 : : /* examine queries to determine which error message to issue */
4039 [ + - + + : 28 : foreach(lc2, newstuff)
+ + ]
4040 : : {
4041 : 24 : Query *q = (Query *) lfirst(lc2);
4042 : :
4043 [ + + ]: 24 : if (q->querySource == QSRC_QUAL_INSTEAD_RULE)
4044 [ + - ]: 4 : ereport(ERROR,
4045 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4046 : : errmsg("conditional DO INSTEAD rules are not supported for data-modifying statements in WITH")));
4047 [ + + ]: 20 : if (q->querySource == QSRC_NON_INSTEAD_RULE)
4048 [ + - ]: 4 : ereport(ERROR,
4049 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4050 : : errmsg("DO ALSO rules are not supported for data-modifying statements in WITH")));
4051 : : }
4052 : :
4053 [ + - ]: 4 : ereport(ERROR,
4054 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4055 : : errmsg("multi-statement DO INSTEAD rules are not supported for data-modifying statements in WITH")));
4056 : : }
4057 : : }
295 dean.a.rasheed@gmail 4058 : 284979 : num_ctes_processed = list_length(parsetree->cteList);
4059 : :
4060 : : /*
4061 : : * If the statement is an insert, update, delete, or merge, adjust its
4062 : : * targetlist as needed, and then fire INSERT/UPDATE/DELETE rules on it.
4063 : : *
4064 : : * SELECT rules are handled later when we have all the queries that should
4065 : : * get executed. Also, utilities aren't rewritten at all (do we still
4066 : : * need that check?)
4067 : : */
8608 tgl@sss.pgh.pa.us 4068 [ + + + + ]: 284979 : if (event != CMD_SELECT && event != CMD_UTILITY)
4069 : : {
4070 : : int result_relation;
4071 : : RangeTblEntry *rt_entry;
4072 : : Relation rt_entry_relation;
4073 : : List *locks;
4074 : : int product_orig_rt_length;
4075 : : List *product_queries;
4153 andres@anarazel.de 4076 : 58136 : bool hasUpdate = false;
2769 dean.a.rasheed@gmail 4077 : 58136 : int values_rte_index = 0;
4078 : 58136 : bool defaults_remaining = false;
4079 : :
8608 tgl@sss.pgh.pa.us 4080 : 58136 : result_relation = parsetree->resultRelation;
4081 [ - + ]: 58136 : Assert(result_relation != 0);
4082 : 58136 : rt_entry = rt_fetch(result_relation, parsetree->rtable);
4083 [ - + ]: 58136 : Assert(rt_entry->rtekind == RTE_RELATION);
4084 : :
4085 : : /*
4086 : : * We can use NoLock here since either the parser or
4087 : : * AcquireRewriteLocks should have locked the rel already.
4088 : : */
193 peter@eisentraut.org 4089 : 58136 : rt_entry_relation = relation_open(rt_entry->relid, NoLock);
4090 : :
4091 : : /*
4092 : : * Rewrite the targetlist as needed for the command type.
4093 : : */
5824 tgl@sss.pgh.pa.us 4094 [ + + ]: 58136 : if (event == CMD_INSERT)
4095 : : {
4096 : : ListCell *lc2;
7354 mail@joeconway.com 4097 : 43862 : RangeTblEntry *values_rte = NULL;
4098 : :
4099 : : /*
4100 : : * Test if it's a multi-row INSERT ... VALUES (...), (...), ... by
4101 : : * looking for a VALUES RTE in the fromlist. For product queries,
4102 : : * we must ignore any already-processed VALUES RTEs from the
4103 : : * original query. These appear at the start of the rangetable.
4104 : : */
1387 dean.a.rasheed@gmail 4105 [ + + + + : 51889 : foreach(lc2, parsetree->jointree->fromlist)
+ + ]
4106 : : {
4107 : 8027 : RangeTblRef *rtr = (RangeTblRef *) lfirst(lc2);
4108 : :
4109 [ + - + + ]: 8027 : if (IsA(rtr, RangeTblRef) && rtr->rtindex > orig_rt_length)
4110 : : {
7354 mail@joeconway.com 4111 : 7795 : RangeTblEntry *rte = rt_fetch(rtr->rtindex,
4112 : : parsetree->rtable);
4113 : :
4114 [ + + ]: 7795 : if (rte->rtekind == RTE_VALUES)
4115 : : {
4116 : : /* should not find more than one VALUES RTE */
1387 dean.a.rasheed@gmail 4117 [ - + ]: 3255 : if (values_rte != NULL)
1387 dean.a.rasheed@gmail 4118 [ # # ]:UBC 0 : elog(ERROR, "more than one VALUES RTE found");
4119 : :
7354 mail@joeconway.com 4120 :CBC 3255 : values_rte = rte;
2769 dean.a.rasheed@gmail 4121 : 3255 : values_rte_index = rtr->rtindex;
4122 : : }
4123 : : }
4124 : : }
4125 : :
7354 mail@joeconway.com 4126 [ + + ]: 43862 : if (values_rte)
4127 : : {
2128 tgl@sss.pgh.pa.us 4128 : 3255 : Bitmapset *unused_values_attrnos = NULL;
4129 : :
4130 : : /* Process the main targetlist ... */
4153 andres@anarazel.de 4131 : 3255 : parsetree->targetList = rewriteTargetListIU(parsetree->targetList,
4132 : : parsetree->commandType,
4133 : : parsetree->override,
4134 : : rt_entry_relation,
4135 : : values_rte,
4136 : : values_rte_index,
4137 : : &unused_values_attrnos);
4138 : : /* ... and the VALUES expression lists */
2758 dean.a.rasheed@gmail 4139 [ + + ]: 3187 : if (!rewriteValuesRTE(parsetree, values_rte, values_rte_index,
4140 : : rt_entry_relation,
4141 : : unused_values_attrnos))
2769 4142 : 52 : defaults_remaining = true;
4143 : : }
4144 : : else
4145 : : {
4146 : : /* Process just the main targetlist */
4153 andres@anarazel.de 4147 : 40555 : parsetree->targetList =
4148 : 40607 : rewriteTargetListIU(parsetree->targetList,
4149 : : parsetree->commandType,
4150 : : parsetree->override,
4151 : : rt_entry_relation,
4152 : : NULL, 0, NULL);
4153 : : }
4154 : :
4155 [ + + ]: 43742 : if (parsetree->onConflict &&
4156 [ + + ]: 1783 : parsetree->onConflict->action == ONCONFLICT_UPDATE)
4157 : : {
4158 : 1048 : parsetree->onConflict->onConflictSet =
4159 : 1048 : rewriteTargetListIU(parsetree->onConflict->onConflictSet,
4160 : : CMD_UPDATE,
4161 : : parsetree->override,
4162 : : rt_entry_relation,
4163 : : NULL, 0, NULL);
4164 : : }
4165 : : }
5824 tgl@sss.pgh.pa.us 4166 [ + + ]: 14274 : else if (event == CMD_UPDATE)
4167 : : {
1637 alvherre@alvh.no-ip. 4168 [ - + ]: 9284 : Assert(parsetree->override == OVERRIDING_NOT_SET);
4153 andres@anarazel.de 4169 : 9264 : parsetree->targetList =
4170 : 9284 : rewriteTargetListIU(parsetree->targetList,
4171 : : parsetree->commandType,
4172 : : parsetree->override,
4173 : : rt_entry_relation,
4174 : : NULL, 0, NULL);
4175 : : }
1637 alvherre@alvh.no-ip. 4176 [ + + ]: 4990 : else if (event == CMD_MERGE)
4177 : : {
4178 [ - + ]: 1906 : Assert(parsetree->override == OVERRIDING_NOT_SET);
4179 : :
4180 : : /*
4181 : : * Rewrite each action targetlist separately
4182 : : */
4183 [ + - + + : 4659 : foreach(lc1, parsetree->mergeActionList)
+ + ]
4184 : : {
4185 : 2757 : MergeAction *action = (MergeAction *) lfirst(lc1);
4186 : :
4187 [ + + - ]: 2757 : switch (action->commandType)
4188 : : {
4189 : 514 : case CMD_NOTHING:
4190 : : case CMD_DELETE: /* Nothing to do here */
4191 : 514 : break;
4192 : 2243 : case CMD_UPDATE:
4193 : : case CMD_INSERT:
4194 : :
4195 : : /*
4196 : : * MERGE actions do not permit multi-row INSERTs, so
4197 : : * there is no VALUES RTE to deal with here.
4198 : : */
4199 : 2239 : action->targetList =
4200 : 2243 : rewriteTargetListIU(action->targetList,
4201 : : action->commandType,
4202 : : action->override,
4203 : : rt_entry_relation,
4204 : : NULL, 0, NULL);
4205 : 2239 : break;
1637 alvherre@alvh.no-ip. 4206 :UBC 0 : default:
4207 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d", action->commandType);
4208 : : break;
4209 : : }
4210 : : }
4211 : : }
5824 tgl@sss.pgh.pa.us 4212 [ - + ]:CBC 3084 : else if (event == CMD_DELETE)
4213 : : {
4214 : : /* Nothing to do here */
4215 : : }
4216 : : else
5824 tgl@sss.pgh.pa.us 4217 [ # # ]:UBC 0 : elog(ERROR, "unrecognized commandType: %d", (int) event);
4218 : :
4219 : : /*
4220 : : * Collect and apply the appropriate rules.
4221 : : */
934 dean.a.rasheed@gmail 4222 :CBC 57992 : locks = matchLocks(event, rt_entry_relation,
4223 : : result_relation, parsetree, &hasUpdate);
4224 : :
1387 4225 : 57980 : product_orig_rt_length = list_length(parsetree->rtable);
3083 simon@2ndQuadrant.co 4226 : 57980 : product_queries = fireRules(parsetree,
4227 : : result_relation,
4228 : : event,
4229 : : locks,
4230 : : &instead,
4231 : : &returning,
4232 : : &qual_product);
4233 : :
4234 : : /*
4235 : : * If we have a VALUES RTE with any remaining untouched DEFAULT items,
4236 : : * and we got any product queries, finalize the VALUES RTE for each
4237 : : * product query (replacing the remaining DEFAULT items with NULLs).
4238 : : * We don't do this for the original query, because we know that it
4239 : : * must be an auto-insert on a view, and so should use the base
4240 : : * relation's defaults for any remaining DEFAULT items.
4241 : : */
2769 dean.a.rasheed@gmail 4242 [ + + + + ]: 57960 : if (defaults_remaining && product_queries != NIL)
4243 : : {
4244 : : ListCell *n;
4245 : :
4246 : : /*
4247 : : * Each product query has its own copy of the VALUES RTE at the
4248 : : * same index in the rangetable, so we must finalize each one.
4249 : : *
4250 : : * Note that if the product query is an INSERT ... SELECT, then
4251 : : * the VALUES RTE will be at the same index in the SELECT part of
4252 : : * the product query rather than the top-level product query
4253 : : * itself.
4254 : : */
4255 [ + - + + : 32 : foreach(n, product_queries)
+ + ]
4256 : : {
4257 : 16 : Query *pt = (Query *) lfirst(n);
4258 : : RangeTblEntry *values_rte;
4259 : :
1305 4260 [ + - ]: 16 : if (pt->commandType == CMD_INSERT &&
4261 [ + - + - : 32 : pt->jointree && IsA(pt->jointree, FromExpr) &&
+ - ]
4262 : 16 : list_length(pt->jointree->fromlist) == 1)
4263 : : {
4264 : 16 : Node *jtnode = (Node *) linitial(pt->jointree->fromlist);
4265 : :
4266 [ + - ]: 16 : if (IsA(jtnode, RangeTblRef))
4267 : : {
4268 : 16 : int rtindex = ((RangeTblRef *) jtnode)->rtindex;
4269 : 16 : RangeTblEntry *src_rte = rt_fetch(rtindex, pt->rtable);
4270 : :
4271 [ + + ]: 16 : if (src_rte->rtekind == RTE_SUBQUERY &&
4272 [ + - ]: 4 : src_rte->subquery &&
4273 [ + - ]: 4 : IsA(src_rte->subquery, Query) &&
4274 [ + - ]: 4 : src_rte->subquery->commandType == CMD_SELECT)
4275 : 4 : pt = src_rte->subquery;
4276 : : }
4277 : : }
4278 : :
4279 : 16 : values_rte = rt_fetch(values_rte_index, pt->rtable);
4280 [ - + ]: 16 : if (values_rte->rtekind != RTE_VALUES)
1305 dean.a.rasheed@gmail 4281 [ # # ]:UBC 0 : elog(ERROR, "failed to find VALUES RTE in product query");
4282 : :
1440 tgl@sss.pgh.pa.us 4283 :CBC 16 : rewriteValuesRTEToNulls(pt, values_rte);
4284 : : }
4285 : : }
4286 : :
4287 : : /*
4288 : : * If there was no unqualified INSTEAD rule, and the target relation
4289 : : * is a view without any INSTEAD OF triggers, see if the view can be
4290 : : * automatically updated. If so, we perform the necessary query
4291 : : * transformation here and add the resulting query to the
4292 : : * product_queries list, so that it gets recursively rewritten if
4293 : : * necessary. For MERGE, the view must be automatically updatable if
4294 : : * any of the merge actions lack a corresponding INSTEAD OF trigger.
4295 : : *
4296 : : * If the view cannot be automatically updated, we throw an error here
4297 : : * which is OK since the query would fail at runtime anyway. Throwing
4298 : : * the error here is preferable to the executor check since we have
4299 : : * more detailed information available about why the view isn't
4300 : : * updatable.
4301 : : */
2441 dean.a.rasheed@gmail 4302 [ + + ]: 57960 : if (!instead &&
5034 tgl@sss.pgh.pa.us 4303 [ + + ]: 57484 : rt_entry_relation->rd_rel->relkind == RELKIND_VIEW &&
934 dean.a.rasheed@gmail 4304 [ + + ]: 2659 : !view_has_instead_trigger(rt_entry_relation, event,
4305 : : parsetree->mergeActionList))
4306 : : {
4307 : : /*
4308 : : * If there were any qualified INSTEAD rules, don't allow the view
4309 : : * to be automatically updated (an unqualified INSTEAD rule or
4310 : : * INSTEAD OF trigger is required).
4311 : : */
2441 4312 [ + + ]: 2390 : if (qual_product != NULL)
934 4313 : 12 : error_view_not_updatable(rt_entry_relation,
4314 : : parsetree->commandType,
4315 : : parsetree->mergeActionList,
4316 : : gettext_noop("Views with conditional DO INSTEAD rules are not automatically updatable."));
4317 : :
4318 : : /*
4319 : : * Attempt to rewrite the query to automatically update the view.
4320 : : * This throws an error if the view can't be automatically
4321 : : * updated.
4322 : : */
5034 tgl@sss.pgh.pa.us 4323 : 2378 : parsetree = rewriteTargetView(parsetree, rt_entry_relation);
4324 : :
4325 : : /*
4326 : : * At this point product_queries contains any DO ALSO rule
4327 : : * actions. Add the rewritten query before or after those. This
4328 : : * must match the handling the original query would have gotten
4329 : : * below, if we allowed it to be included again.
4330 : : */
4331 [ + + ]: 2198 : if (parsetree->commandType == CMD_INSERT)
4332 : 792 : product_queries = lcons(parsetree, product_queries);
4333 : : else
4334 : 1406 : product_queries = lappend(product_queries, parsetree);
4335 : :
4336 : : /*
4337 : : * Set the "instead" flag, as if there had been an unqualified
4338 : : * INSTEAD, to prevent the original query from being included a
4339 : : * second time below. The transformation will have rewritten any
4340 : : * RETURNING list, so we can also set "returning" to forestall
4341 : : * throwing an error below.
4342 : : */
4343 : 2198 : instead = true;
4344 : 2198 : returning = true;
4153 andres@anarazel.de 4345 : 2198 : updatableview = true;
4346 : : }
4347 : :
4348 : : /*
4349 : : * If we got any product queries, recursively rewrite them --- but
4350 : : * first check for recursion!
4351 : : */
4862 bruce@momjian.us 4352 [ + + ]: 57768 : if (product_queries != NIL)
4353 : : {
4354 : : ListCell *n;
4355 : : rewrite_event *rev;
4356 : :
4357 [ + + + + : 3630 : foreach(n, rewrite_events)
+ + ]
4358 : : {
4359 : 644 : rev = (rewrite_event *) lfirst(n);
4360 [ - + ]: 644 : if (rev->relation == RelationGetRelid(rt_entry_relation) &&
4862 bruce@momjian.us 4361 [ # # ]:UBC 0 : rev->event == event)
4362 [ # # ]: 0 : ereport(ERROR,
4363 : : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
4364 : : errmsg("infinite recursion detected in rules for relation \"%s\"",
4365 : : RelationGetRelationName(rt_entry_relation))));
4366 : : }
4367 : :
284 michael@paquier.xyz 4368 :CBC 2986 : rev = palloc_object(rewrite_event);
4862 bruce@momjian.us 4369 : 2986 : rev->relation = RelationGetRelid(rt_entry_relation);
4370 : 2986 : rev->event = event;
2622 tgl@sss.pgh.pa.us 4371 : 2986 : rewrite_events = lappend(rewrite_events, rev);
4372 : :
4862 bruce@momjian.us 4373 [ + - + + : 6032 : foreach(n, product_queries)
+ + ]
4374 : : {
4375 : 3142 : Query *pt = (Query *) lfirst(n);
4376 : : List *newstuff;
4377 : :
4378 : : /*
4379 : : * For an updatable view, pt might be the rewritten version of
4380 : : * the original query, in which case we pass on orig_rt_length
4381 : : * to finish processing any VALUES RTE it contained.
4382 : : *
4383 : : * Otherwise, we have a product query created by fireRules().
4384 : : * Any VALUES RTEs from the original query have been fully
4385 : : * processed, and must be skipped when we recurse.
4386 : : */
1387 dean.a.rasheed@gmail 4387 [ + + ]: 3142 : newstuff = RewriteQuery(pt, rewrite_events,
4388 : : pt == parsetree ?
4389 : : orig_rt_length :
4390 : : product_orig_rt_length,
4391 : : num_ctes_processed);
4862 bruce@momjian.us 4392 : 3046 : rewritten = list_concat(rewritten, newstuff);
4393 : : }
4394 : :
2622 tgl@sss.pgh.pa.us 4395 : 2890 : rewrite_events = list_delete_last(rewrite_events);
4396 : : }
4397 : :
4398 : : /*
4399 : : * If there is an INSTEAD, and the original query has a RETURNING, we
4400 : : * have to have found a RETURNING in the rule(s), else fail. (Because
4401 : : * DefineQueryRewrite only allows RETURNING in unconditional INSTEAD
4402 : : * rules, there's no need to worry whether the substituted RETURNING
4403 : : * will actually be executed --- it must be.)
4404 : : */
7323 4405 [ + + + + ]: 57672 : if ((instead || qual_product != NULL) &&
4406 [ + + ]: 2794 : parsetree->returningList &&
4407 [ + + ]: 324 : !returning)
4408 : : {
4409 [ + - - - ]: 4 : switch (event)
4410 : : {
4411 : 4 : case CMD_INSERT:
4412 [ + - ]: 4 : ereport(ERROR,
4413 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4414 : : errmsg("cannot perform INSERT RETURNING on relation \"%s\"",
4415 : : RelationGetRelationName(rt_entry_relation)),
4416 : : errhint("You need an unconditional ON INSERT DO INSTEAD rule with a RETURNING clause.")));
4417 : : break;
7323 tgl@sss.pgh.pa.us 4418 :UBC 0 : case CMD_UPDATE:
4419 [ # # ]: 0 : ereport(ERROR,
4420 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4421 : : errmsg("cannot perform UPDATE RETURNING on relation \"%s\"",
4422 : : RelationGetRelationName(rt_entry_relation)),
4423 : : errhint("You need an unconditional ON UPDATE DO INSTEAD rule with a RETURNING clause.")));
4424 : : break;
4425 : 0 : case CMD_DELETE:
4426 [ # # ]: 0 : ereport(ERROR,
4427 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4428 : : errmsg("cannot perform DELETE RETURNING on relation \"%s\"",
4429 : : RelationGetRelationName(rt_entry_relation)),
4430 : : errhint("You need an unconditional ON DELETE DO INSTEAD rule with a RETURNING clause.")));
4431 : : break;
4432 : 0 : default:
4433 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d",
4434 : : (int) event);
4435 : : break;
4436 : : }
4437 : : }
4438 : :
4439 : : /*
4440 : : * Updatable views are supported by ON CONFLICT, so don't prevent that
4441 : : * case from proceeding
4442 : : */
4153 andres@anarazel.de 4443 [ + + + + ]:CBC 57668 : if (parsetree->onConflict &&
4444 [ - + ]: 1603 : (product_queries != NIL || hasUpdate) &&
4445 [ + + ]: 172 : !updatableview)
4138 bruce@momjian.us 4446 [ + - ]: 8 : ereport(ERROR,
4447 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4448 : : errmsg("INSERT with ON CONFLICT clause cannot be used with table that has INSERT or UPDATE rules")));
4449 : :
2799 andres@anarazel.de 4450 : 57660 : table_close(rt_entry_relation, NoLock);
4451 : : }
4452 : :
4453 : : /*
4454 : : * For INSERTs, the original query is done first; for UPDATE/DELETE, it is
4455 : : * done last. This is needed because update and delete rule actions might
4456 : : * not do anything if they are invoked after the update or delete is
4457 : : * performed. The command counter increment between the query executions
4458 : : * makes the deleted (and maybe the updated) tuples disappear so the scans
4459 : : * for them in the rule actions cannot find them.
4460 : : *
4461 : : * If we found any unqualified INSTEAD, the original query is not done at
4462 : : * all, in any form. Otherwise, we add the modified form if qualified
4463 : : * INSTEADs were found, else the unmodified form.
4464 : : */
8737 tgl@sss.pgh.pa.us 4465 [ + + ]: 284503 : if (!instead)
4466 : : {
4467 [ + + ]: 281937 : if (parsetree->commandType == CMD_INSERT)
4468 : : {
4469 [ + + ]: 42602 : if (qual_product != NULL)
4470 : 196 : rewritten = lcons(qual_product, rewritten);
4471 : : else
4472 : 42406 : rewritten = lcons(parsetree, rewritten);
4473 : : }
4474 : : else
4475 : : {
4476 [ + + ]: 239335 : if (qual_product != NULL)
4477 : 20 : rewritten = lappend(rewritten, qual_product);
4478 : : else
4479 : 239315 : rewritten = lappend(rewritten, parsetree);
4480 : : }
4481 : : }
4482 : :
4483 : : /*
4484 : : * If the original query has a CTE list, and we generated more than one
4485 : : * non-utility result query, we have to fail because we'll have copied the
4486 : : * CTE list into each result query. That would break the expectation of
4487 : : * single evaluation of CTEs. This could possibly be fixed by
4488 : : * restructuring so that a CTE list can be shared across multiple Query
4489 : : * and PlannableStatement nodes.
4490 : : */
5584 4491 [ + + ]: 284503 : if (parsetree->cteList != NIL)
4492 : : {
5582 bruce@momjian.us 4493 : 1660 : int qcount = 0;
4494 : :
5584 tgl@sss.pgh.pa.us 4495 [ + - + + : 3320 : foreach(lc1, rewritten)
+ + ]
4496 : : {
4497 : 1660 : Query *q = (Query *) lfirst(lc1);
4498 : :
4499 [ + - ]: 1660 : if (q->commandType != CMD_UTILITY)
4500 : 1660 : qcount++;
4501 : : }
4502 [ - + ]: 1660 : if (qcount > 1)
5584 tgl@sss.pgh.pa.us 4503 [ # # ]:UBC 0 : ereport(ERROR,
4504 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4505 : : errmsg("WITH cannot be used in a query that is rewritten by rules into multiple queries")));
4506 : : }
4507 : :
10605 bruce@momjian.us 4508 :CBC 284503 : return rewritten;
4509 : : }
4510 : :
4511 : :
4512 : : /*
4513 : : * Get a table's generated columns
4514 : : *
4515 : : * If include_stored is true, both stored and virtual generated columns are
4516 : : * returned. Otherwise, only virtual generated columns are returned.
4517 : : *
4518 : : * Returns a list of TargetEntry, one for each generated column, containing
4519 : : * the attribute numbers and generation expressions.
4520 : : */
4521 : : static List *
152 rguo@postgresql.org 4522 : 1419 : get_generated_columns(Relation rel, int rt_index, bool include_stored)
4523 : : {
4524 : 1419 : List *gen_cols = NIL;
4525 : : TupleDesc tupdesc;
4526 : :
590 peter@eisentraut.org 4527 : 1419 : tupdesc = RelationGetDescr(rel);
152 rguo@postgresql.org 4528 [ + + ]: 1419 : if (tupdesc->constr &&
4529 [ + + + - ]: 571 : (tupdesc->constr->has_generated_virtual ||
4530 [ + + ]: 256 : (include_stored && tupdesc->constr->has_generated_stored)))
4531 : : {
590 peter@eisentraut.org 4532 [ + + ]: 1306 : for (int i = 0; i < tupdesc->natts; i++)
4533 : : {
4534 : 975 : Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
4535 : :
152 rguo@postgresql.org 4536 [ + + + + ]: 975 : if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL ||
4537 [ + + ]: 48 : (include_stored && attr->attgenerated == ATTRIBUTE_GENERATED_STORED))
4538 : : {
4539 : : Node *defexpr;
4540 : : TargetEntry *te;
4541 : :
572 4542 : 451 : defexpr = build_generation_expression(rel, i + 1);
590 peter@eisentraut.org 4543 : 451 : ChangeVarNodes(defexpr, 1, rt_index, 0);
4544 : :
572 rguo@postgresql.org 4545 : 451 : te = makeTargetEntry((Expr *) defexpr, i + 1, 0, false);
152 4546 : 451 : gen_cols = lappend(gen_cols, te);
4547 : : }
4548 : : }
4549 : : }
4550 : :
4551 : 1419 : return gen_cols;
4552 : : }
4553 : :
4554 : : /*
4555 : : * Expand virtual generated columns in an expression
4556 : : *
4557 : : * This is for expressions that are not part of a query, such as default
4558 : : * expressions or index predicates. The rt_index is usually 1.
4559 : : */
4560 : : Node *
590 peter@eisentraut.org 4561 : 10288 : expand_generated_columns_in_expr(Node *node, Relation rel, int rt_index)
4562 : : {
4563 : 10288 : TupleDesc tupdesc = RelationGetDescr(rel);
4564 : :
4565 [ + + + + ]: 10288 : if (tupdesc->constr && tupdesc->constr->has_generated_virtual)
4566 : : {
4567 : : RangeTblEntry *rte;
4568 : : List *vcols;
4569 : :
4570 : 299 : rte = makeNode(RangeTblEntry);
4571 : : /* eref needs to be set, but the actual name doesn't matter */
4572 : 299 : rte->eref = makeAlias(RelationGetRelationName(rel), NIL);
4573 : 299 : rte->rtekind = RTE_RELATION;
4574 : 299 : rte->relid = RelationGetRelid(rel);
4575 : :
152 rguo@postgresql.org 4576 : 299 : vcols = get_generated_columns(rel, rt_index, false);
4577 : :
4578 [ + - ]: 299 : if (vcols)
4579 : : {
4580 : : /*
4581 : : * Passing NULL for outer_hasSubLinks is safe because generation
4582 : : * expressions cannot contain SubLinks, so the replacement cannot
4583 : : * introduce any.
4584 : : */
4585 : 299 : node = ReplaceVarsFromTargetList(node, rt_index, 0, rte, vcols, 0,
4586 : : REPLACEVARS_CHANGE_VARNO, rt_index,
4587 : : NULL);
4588 : : }
4589 : : }
4590 : :
590 peter@eisentraut.org 4591 : 10288 : return node;
4592 : : }
4593 : :
4594 : : /*
4595 : : * Build the generation expression for a generated column.
4596 : : *
4597 : : * Error out if there is no generation expression found for the given column.
4598 : : */
4599 : : Node *
572 rguo@postgresql.org 4600 : 2057 : build_generation_expression(Relation rel, int attrno)
4601 : : {
4602 : 2057 : TupleDesc rd_att = RelationGetDescr(rel);
4603 : 2057 : Form_pg_attribute att_tup = TupleDescAttr(rd_att, attrno - 1);
4604 : : Node *defexpr;
4605 : : Oid attcollid;
4606 : :
152 4607 [ + - + + : 2057 : Assert(rd_att->constr &&
- + ]
4608 : : (rd_att->constr->has_generated_virtual ||
4609 : : rd_att->constr->has_generated_stored));
4610 [ + + - + ]: 2057 : Assert(att_tup->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL ||
4611 : : att_tup->attgenerated == ATTRIBUTE_GENERATED_STORED);
4612 : :
572 4613 : 2057 : defexpr = build_column_default(rel, attrno);
4614 [ - + ]: 2057 : if (defexpr == NULL)
572 rguo@postgresql.org 4615 [ # # ]:UBC 0 : elog(ERROR, "no generation expression found for column number %d of table \"%s\"",
4616 : : attrno, RelationGetRelationName(rel));
4617 : :
4618 : : /*
4619 : : * If the column definition has a collation and it is different from the
4620 : : * collation of the generation expression, put a COLLATE clause around the
4621 : : * expression.
4622 : : */
572 rguo@postgresql.org 4623 :CBC 2057 : attcollid = att_tup->attcollation;
4624 [ + + + + ]: 2057 : if (attcollid && attcollid != exprCollation(defexpr))
4625 : : {
4626 : 10 : CollateExpr *ce = makeNode(CollateExpr);
4627 : :
4628 : 10 : ce->arg = (Expr *) defexpr;
4629 : 10 : ce->collOid = attcollid;
4630 : 10 : ce->location = -1;
4631 : :
4632 : 10 : defexpr = (Node *) ce;
4633 : : }
4634 : :
4635 : 2057 : return defexpr;
4636 : : }
4637 : :
4638 : :
4639 : : /*
4640 : : * QueryRewrite -
4641 : : * Primary entry point to the query rewriter.
4642 : : * Rewrite one query via query rewrite system, possibly returning 0
4643 : : * or many queries.
4644 : : *
4645 : : * NOTE: the parsetree must either have come straight from the parser,
4646 : : * or have been scanned by AcquireRewriteLocks to acquire suitable locks.
4647 : : */
4648 : : List *
9481 tgl@sss.pgh.pa.us 4649 : 281615 : QueryRewrite(Query *parsetree)
4650 : : {
478 drowley@postgresql.o 4651 : 281615 : int64 input_query_id = parsetree->queryId;
4652 : : List *querylist;
4653 : : List *results;
4654 : : ListCell *l;
4655 : : CmdType origCmdType;
4656 : : bool foundOriginalQuery;
4657 : : Query *lastInstead;
4658 : :
4659 : : /*
4660 : : * This function is only applied to top-level original queries
4661 : : */
5686 tgl@sss.pgh.pa.us 4662 [ - + ]: 281615 : Assert(parsetree->querySource == QSRC_ORIGINAL);
4663 [ - + ]: 281615 : Assert(parsetree->canSetTag);
4664 : :
4665 : : /*
4666 : : * Step 1
4667 : : *
4668 : : * Apply all non-SELECT rules possibly getting 0 or many queries
4669 : : */
295 dean.a.rasheed@gmail 4670 : 281615 : querylist = RewriteQuery(parsetree, NIL, 0, 0);
4671 : :
4672 : : /*
4673 : : * Step 2
4674 : : *
4675 : : * Apply all the RIR rules on each query
4676 : : *
4677 : : * This is also a handy place to mark each query with the original queryId
4678 : : */
5824 tgl@sss.pgh.pa.us 4679 : 281215 : results = NIL;
9980 bruce@momjian.us 4680 [ + + + + : 562814 : foreach(l, querylist)
+ + ]
4681 : : {
9313 4682 : 281675 : Query *query = (Query *) lfirst(l);
4683 : :
3081 tgl@sss.pgh.pa.us 4684 : 281675 : query = fireRIRrules(query, NIL);
4685 : :
5290 4686 : 281599 : query->queryId = input_query_id;
4687 : :
9481 4688 : 281599 : results = lappend(results, query);
4689 : : }
4690 : :
4691 : : /*
4692 : : * Step 3
4693 : : *
4694 : : * Determine which, if any, of the resulting queries is supposed to set
4695 : : * the command-result tag; and update the canSetTag fields accordingly.
4696 : : *
4697 : : * If the original query is still in the list, it sets the command tag.
4698 : : * Otherwise, the last INSTEAD query of the same kind as the original is
4699 : : * allowed to set the tag. (Note these rules can leave us with no query
4700 : : * setting the tag. The tcop code has to cope with this by setting up a
4701 : : * default tag based on the original un-rewritten query.)
4702 : : *
4703 : : * The Asserts verify that at most one query in the result list is marked
4704 : : * canSetTag. If we aren't checking asserts, we can fall out of the loop
4705 : : * as soon as we find the original query.
4706 : : */
8542 4707 : 281139 : origCmdType = parsetree->commandType;
4708 : 281139 : foundOriginalQuery = false;
4709 : 281139 : lastInstead = NULL;
4710 : :
4711 [ + + + + : 562738 : foreach(l, results)
+ + ]
4712 : : {
4713 : 281599 : Query *query = (Query *) lfirst(l);
4714 : :
4715 [ + + ]: 281599 : if (query->querySource == QSRC_ORIGINAL)
4716 : : {
4717 [ - + ]: 280695 : Assert(query->canSetTag);
4718 [ - + ]: 280695 : Assert(!foundOriginalQuery);
4719 : 280695 : foundOriginalQuery = true;
4720 : : #ifndef USE_ASSERT_CHECKING
4721 : : break;
4722 : : #endif
4723 : : }
4724 : : else
4725 : : {
4726 [ - + ]: 904 : Assert(!query->canSetTag);
4727 [ + + ]: 904 : if (query->commandType == origCmdType &&
4728 [ + + ]: 720 : (query->querySource == QSRC_INSTEAD_RULE ||
4729 [ + + ]: 360 : query->querySource == QSRC_QUAL_INSTEAD_RULE))
4730 : 512 : lastInstead = query;
4731 : : }
4732 : : }
4733 : :
4734 [ + + + + ]: 281139 : if (!foundOriginalQuery && lastInstead != NULL)
4735 : 376 : lastInstead->canSetTag = true;
4736 : :
9481 4737 : 281139 : return results;
4738 : : }
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