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 Node *expand_generated_columns_internal(Node *node, Relation rel, int rt_index,
100 : : RangeTblEntry *rte, int result_relation);
101 : :
102 : :
103 : : /*
104 : : * AcquireRewriteLocks -
105 : : * Acquire suitable locks on all the relations mentioned in the Query.
106 : : * These locks will ensure that the relation schemas don't change under us
107 : : * while we are rewriting, planning, and executing the query.
108 : : *
109 : : * Caution: this may modify the querytree, therefore caller should usually
110 : : * have done a copyObject() to make a writable copy of the querytree in the
111 : : * current memory context.
112 : : *
113 : : * forExecute indicates that the query is about to be executed. If so,
114 : : * we'll acquire the lock modes specified in the RTE rellockmode fields.
115 : : * If forExecute is false, AccessShareLock is acquired on all relations.
116 : : * This case is suitable for ruleutils.c, for example, where we only need
117 : : * schema stability and we don't intend to actually modify any relations.
118 : : *
119 : : * forUpdatePushedDown indicates that a pushed-down FOR [KEY] UPDATE/SHARE
120 : : * applies to the current subquery, requiring all rels to be opened with at
121 : : * least RowShareLock. This should always be false at the top of the
122 : : * recursion. When it is true, we adjust RTE rellockmode fields to reflect
123 : : * the higher lock level. This flag is ignored if forExecute is false.
124 : : *
125 : : * A secondary purpose of this routine is to fix up JOIN RTE references to
126 : : * dropped columns (see details below). Such RTEs are modified in-place.
127 : : *
128 : : * This processing can, and for efficiency's sake should, be skipped when the
129 : : * querytree has just been built by the parser: parse analysis already got
130 : : * all the same locks we'd get here, and the parser will have omitted dropped
131 : : * columns from JOINs to begin with. But we must do this whenever we are
132 : : * dealing with a querytree produced earlier than the current command.
133 : : *
134 : : * About JOINs and dropped columns: although the parser never includes an
135 : : * already-dropped column in a JOIN RTE's alias var list, it is possible for
136 : : * such a list in a stored rule to include references to dropped columns.
137 : : * (If the column is not explicitly referenced anywhere else in the query,
138 : : * the dependency mechanism won't consider it used by the rule and so won't
139 : : * prevent the column drop.) To support get_rte_attribute_is_dropped(), we
140 : : * replace join alias vars that reference dropped columns with null pointers.
141 : : *
142 : : * (In PostgreSQL 8.0, we did not do this processing but instead had
143 : : * get_rte_attribute_is_dropped() recurse to detect dropped columns in joins.
144 : : * That approach had horrible performance unfortunately; in particular
145 : : * construction of a nested join was O(N^2) in the nesting depth.)
146 : : */
147 : : void
4392 tgl@sss.pgh.pa.us 148 :CBC 24392 : AcquireRewriteLocks(Query *parsetree,
149 : : bool forExecute,
150 : : bool forUpdatePushedDown)
151 : : {
152 : : ListCell *l;
153 : : int rt_index;
154 : : acquireLocksOnSubLinks_context context;
155 : :
156 : 24392 : context.for_execute = forExecute;
157 : :
158 : : /*
159 : : * First, process RTEs of the current query level.
160 : : */
7590 161 : 24392 : rt_index = 0;
162 [ + + + + : 82229 : foreach(l, parsetree->rtable)
+ + ]
163 : : {
164 : 57837 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
165 : : Relation rel;
166 : : LOCKMODE lockmode;
167 : : List *newaliasvars;
168 : : Index curinputvarno;
169 : : RangeTblEntry *curinputrte;
170 : : ListCell *ll;
171 : :
172 : 57837 : ++rt_index;
173 [ + + + + ]: 57837 : switch (rte->rtekind)
174 : : {
175 : 31852 : case RTE_RELATION:
176 : :
177 : : /*
178 : : * Grab the appropriate lock type for the relation, and do not
179 : : * release it until end of transaction. This protects the
180 : : * rewriter, planner, and executor against schema changes
181 : : * mid-query.
182 : : *
183 : : * If forExecute is false, ignore rellockmode and just use
184 : : * AccessShareLock.
185 : : */
4392 186 [ + + ]: 31852 : if (!forExecute)
187 : 4008 : lockmode = AccessShareLock;
2723 188 [ + + ]: 27844 : else if (forUpdatePushedDown)
189 : : {
190 : : /* Upgrade RTE's lock mode to reflect pushed-down lock */
191 [ + - ]: 48 : if (rte->rellockmode == AccessShareLock)
192 : 48 : rte->rellockmode = RowShareLock;
2721 193 : 48 : lockmode = rte->rellockmode;
194 : : }
195 : : else
196 : 27796 : lockmode = rte->rellockmode;
197 : :
4 peter@eisentraut.org 198 :GNC 31852 : rel = relation_open(rte->relid, lockmode);
199 : :
200 : : /*
201 : : * While we have the relation open, update the RTE's relkind,
202 : : * just in case it changed since this rule was made.
203 : : */
5500 tgl@sss.pgh.pa.us 204 :CBC 31852 : rte->relkind = rel->rd_rel->relkind;
205 : :
4 peter@eisentraut.org 206 :GNC 31852 : relation_close(rel, NoLock);
7590 tgl@sss.pgh.pa.us 207 :CBC 31852 : break;
208 : :
209 : 14681 : case RTE_JOIN:
210 : :
211 : : /*
212 : : * Scan the join's alias var list to see if any columns have
213 : : * been dropped, and if so replace those Vars with null
214 : : * pointers.
215 : : *
216 : : * Since a join has only two inputs, we can expect to see
217 : : * multiple references to the same input RTE; optimize away
218 : : * multiple fetches.
219 : : */
220 : 14681 : newaliasvars = NIL;
7589 221 : 14681 : curinputvarno = 0;
222 : 14681 : curinputrte = NULL;
7590 223 [ + - + + : 568958 : foreach(ll, rte->joinaliasvars)
+ + ]
224 : : {
4618 225 : 554277 : Var *aliasitem = (Var *) lfirst(ll);
226 : 554277 : Var *aliasvar = aliasitem;
227 : :
228 : : /* Look through any implicit coercion */
229 : 554277 : aliasvar = (Var *) strip_implicit_coercions((Node *) aliasvar);
230 : :
231 : : /*
232 : : * If the list item isn't a simple Var, then it must
233 : : * represent a merged column, ie a USING column, and so it
234 : : * couldn't possibly be dropped, since it's referenced in
235 : : * the join clause. (Conceivably it could also be a null
236 : : * pointer already? But that's OK too.)
237 : : */
238 [ + - + + ]: 554277 : if (aliasvar && IsA(aliasvar, Var))
239 : : {
240 : : /*
241 : : * The elements of an alias list have to refer to
242 : : * earlier RTEs of the same rtable, because that's the
243 : : * order the planner builds things in. So we already
244 : : * processed the referenced RTE, and so it's safe to
245 : : * use get_rte_attribute_is_dropped on it. (This might
246 : : * not hold after rewriting or planning, but it's OK
247 : : * to assume here.)
248 : : */
7590 249 [ - + ]: 554190 : Assert(aliasvar->varlevelsup == 0);
7589 250 [ + + ]: 554190 : if (aliasvar->varno != curinputvarno)
251 : : {
252 : 38056 : curinputvarno = aliasvar->varno;
253 [ - + ]: 38056 : if (curinputvarno >= rt_index)
7589 tgl@sss.pgh.pa.us 254 [ # # ]:UBC 0 : elog(ERROR, "unexpected varno %d in JOIN RTE %d",
255 : : curinputvarno, rt_index);
7589 tgl@sss.pgh.pa.us 256 :CBC 38056 : curinputrte = rt_fetch(curinputvarno,
257 : : parsetree->rtable);
258 : : }
259 [ + + ]: 554190 : if (get_rte_attribute_is_dropped(curinputrte,
260 : 554190 : aliasvar->varattno))
261 : : {
262 : : /* Replace the join alias item with a NULL */
4618 263 : 3 : aliasitem = NULL;
264 : : }
265 : : }
266 : 554277 : newaliasvars = lappend(newaliasvars, aliasitem);
267 : : }
7590 268 : 14681 : rte->joinaliasvars = newaliasvars;
269 : 14681 : break;
270 : :
271 : 5078 : case RTE_SUBQUERY:
272 : :
273 : : /*
274 : : * The subquery RTE itself is all right, but we have to
275 : : * recurse to process the represented subquery.
276 : : */
5982 277 : 5078 : AcquireRewriteLocks(rte->subquery,
278 : : forExecute,
279 [ + - - + ]: 10156 : (forUpdatePushedDown ||
3189 280 : 5078 : get_parse_rowmark(parsetree, rt_index) != NULL));
7590 281 : 5078 : break;
282 : :
283 : 6226 : default:
284 : : /* ignore other types of RTEs */
285 : 6226 : break;
286 : : }
287 : : }
288 : :
289 : : /* Recurse into subqueries in WITH */
6371 290 [ + + + + : 24543 : foreach(l, parsetree->cteList)
+ + ]
291 : : {
292 : 151 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(l);
293 : :
4392 294 : 151 : AcquireRewriteLocks((Query *) cte->ctequery, forExecute, false);
295 : : }
296 : :
297 : : /*
298 : : * Recurse into sublink subqueries, too. But we already did the ones in
299 : : * the rtable and cteList.
300 : : */
7590 301 [ + + ]: 24392 : if (parsetree->hasSubLinks)
4392 302 : 1173 : query_tree_walker(parsetree, acquireLocksOnSubLinks, &context,
303 : : QTW_IGNORE_RC_SUBQUERIES);
7590 304 : 24392 : }
305 : :
306 : : /*
307 : : * Walker to find sublink subqueries for AcquireRewriteLocks
308 : : */
309 : : static bool
4392 310 : 104743 : acquireLocksOnSubLinks(Node *node, acquireLocksOnSubLinks_context *context)
311 : : {
7590 312 [ + + ]: 104743 : if (node == NULL)
313 : 20880 : return false;
314 [ + + ]: 83863 : if (IsA(node, SubLink))
315 : : {
316 : 2373 : SubLink *sub = (SubLink *) node;
317 : :
318 : : /* Do what we came for */
4392 319 : 2373 : AcquireRewriteLocks((Query *) sub->subselect,
320 : 2373 : context->for_execute,
321 : : false);
322 : : /* Fall through to process lefthand args of SubLink */
323 : : }
324 : :
325 : : /*
326 : : * Do NOT recurse into Query nodes, because AcquireRewriteLocks already
327 : : * processed subselects of subselects for us.
328 : : */
7590 329 : 83863 : return expression_tree_walker(node, acquireLocksOnSubLinks, context);
330 : : }
331 : :
332 : :
333 : : /*
334 : : * rewriteRuleAction -
335 : : * Rewrite the rule action with appropriate qualifiers (taken from
336 : : * the triggering query).
337 : : *
338 : : * Input arguments:
339 : : * parsetree - original query
340 : : * rule_action - one action (query) of a rule
341 : : * rule_qual - WHERE condition of rule, or NULL if unconditional
342 : : * rt_index - RT index of result relation in original query
343 : : * event - type of rule event
344 : : * Output arguments:
345 : : * *returning_flag - set true if we rewrite RETURNING clause in rule_action
346 : : * (must be initialized to false)
347 : : * Return value:
348 : : * rewritten form of rule_action
349 : : */
350 : : static Query *
9041 351 : 708 : rewriteRuleAction(Query *parsetree,
352 : : Query *rule_action,
353 : : Node *rule_qual,
354 : : int rt_index,
355 : : CmdType event,
356 : : bool *returning_flag)
357 : : {
358 : : int current_varno,
359 : : new_varno;
360 : : int rt_length;
361 : : Query *sub_action;
362 : : Query **sub_action_ptr;
363 : : acquireLocksOnSubLinks_context context;
364 : : ListCell *lc;
365 : :
4392 366 : 708 : context.for_execute = true;
367 : :
368 : : /*
369 : : * Make modifiable copies of rule action and qual (what we're passed are
370 : : * the stored versions in the relcache; don't touch 'em!).
371 : : */
3293 peter_e@gmx.net 372 : 708 : rule_action = copyObject(rule_action);
373 : 708 : rule_qual = copyObject(rule_qual);
374 : :
375 : : /*
376 : : * Acquire necessary locks and fix any deleted JOIN RTE entries.
377 : : */
4392 tgl@sss.pgh.pa.us 378 : 708 : AcquireRewriteLocks(rule_action, true, false);
379 : 708 : (void) acquireLocksOnSubLinks(rule_qual, &context);
380 : :
9041 381 : 708 : current_varno = rt_index;
7959 neilc@samurai.com 382 : 708 : rt_length = list_length(parsetree->rtable);
9041 tgl@sss.pgh.pa.us 383 : 708 : new_varno = PRS2_NEW_VARNO + rt_length;
384 : :
385 : : /*
386 : : * Adjust rule action and qual to offset its varnos, so that we can merge
387 : : * its rtable with the main parsetree's rtable.
388 : : *
389 : : * If the rule action is an INSERT...SELECT, the OLD/NEW rtable entries
390 : : * will be in the SELECT part, and we have to modify that rather than the
391 : : * top-level INSERT (kluge!).
392 : : */
393 : 708 : sub_action = getInsertSelectQuery(rule_action, &sub_action_ptr);
394 : :
9231 395 : 708 : OffsetVarNodes((Node *) sub_action, rt_length, 0);
9041 396 : 708 : OffsetVarNodes(rule_qual, rt_length, 0);
397 : : /* but references to OLD should point at original rt_index */
9231 398 : 708 : ChangeVarNodes((Node *) sub_action,
399 : : PRS2_OLD_VARNO + rt_length, rt_index, 0);
9041 400 : 708 : ChangeVarNodes(rule_qual,
401 : : PRS2_OLD_VARNO + rt_length, rt_index, 0);
402 : :
403 : : /*
404 : : * Mark any subquery RTEs in the rule action as LATERAL if they contain
405 : : * Vars referring to the current query level (references to NEW/OLD).
406 : : * Those really are lateral references, but we've historically not
407 : : * required users to mark such subqueries with LATERAL explicitly. But
408 : : * the planner will complain if such Vars exist in a non-LATERAL subquery,
409 : : * so we have to fix things up here.
410 : : */
1114 dean.a.rasheed@gmail 411 [ + + + + : 2817 : foreach(lc, sub_action->rtable)
+ + ]
412 : : {
413 : 2109 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
414 : :
415 [ + + + - : 2115 : if (rte->rtekind == RTE_SUBQUERY && !rte->lateral &&
+ - ]
416 : 6 : contain_vars_of_level((Node *) rte->subquery, 1))
417 : 6 : rte->lateral = true;
418 : : }
419 : :
420 : : /*
421 : : * Generate expanded rtable consisting of main parsetree's rtable plus
422 : : * rule action's rtable; this becomes the complete rtable for the rule
423 : : * action. Some of the entries may be unused after we finish rewriting,
424 : : * but we leave them all in place to avoid having to adjust the query's
425 : : * varnos. RT entries that are not referenced in the completed jointree
426 : : * will be ignored by the planner, so they do not affect query semantics.
427 : : *
428 : : * Also merge RTEPermissionInfo lists to ensure that all permissions are
429 : : * checked correctly.
430 : : *
431 : : * If the rule is INSTEAD, then the original query won't be executed at
432 : : * all, and so its rteperminfos must be preserved so that the executor
433 : : * will do the correct permissions checks on the relations referenced in
434 : : * it. This allows us to check that the caller has, say, insert-permission
435 : : * on a view, when the view is not semantically referenced at all in the
436 : : * resulting query.
437 : : *
438 : : * When a rule is not INSTEAD, the permissions checks done using the
439 : : * copied entries will be redundant with those done during execution of
440 : : * the original query, but we don't bother to treat that case differently.
441 : : *
442 : : * NOTE: because planner will destructively alter rtable and rteperminfos,
443 : : * we must ensure that rule action's lists are separate and shares no
444 : : * substructure with the main query's lists. Hence do a deep copy here
445 : : * for both.
446 : : */
447 : : {
1195 alvherre@alvh.no-ip. 448 : 708 : List *rtable_tail = sub_action->rtable;
449 : 708 : List *perminfos_tail = sub_action->rteperminfos;
450 : :
451 : : /*
452 : : * RewriteQuery relies on the fact that RT entries from the original
453 : : * query appear at the start of the expanded rtable, so we put the
454 : : * action's original table at the end of the list.
455 : : */
456 : 708 : sub_action->rtable = copyObject(parsetree->rtable);
457 : 708 : sub_action->rteperminfos = copyObject(parsetree->rteperminfos);
458 : 708 : CombineRangeTables(&sub_action->rtable, &sub_action->rteperminfos,
459 : : rtable_tail, perminfos_tail);
460 : : }
461 : :
462 : : /*
463 : : * There could have been some SubLinks in parsetree's rtable, in which
464 : : * case we'd better mark the sub_action correctly.
465 : : */
6381 tgl@sss.pgh.pa.us 466 [ + + + - ]: 708 : if (parsetree->hasSubLinks && !sub_action->hasSubLinks)
467 : : {
468 [ + - + + : 33 : foreach(lc, parsetree->rtable)
+ + ]
469 : : {
470 : 24 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
471 : :
472 [ + - - - : 24 : switch (rte->rtekind)
+ ]
473 : : {
3886 474 : 21 : case RTE_RELATION:
475 : 21 : sub_action->hasSubLinks =
476 : 21 : checkExprHasSubLink((Node *) rte->tablesample);
477 : 21 : break;
6381 tgl@sss.pgh.pa.us 478 :UBC 0 : case RTE_FUNCTION:
479 : 0 : sub_action->hasSubLinks =
4497 480 : 0 : checkExprHasSubLink((Node *) rte->functions);
6381 481 : 0 : break;
3294 alvherre@alvh.no-ip. 482 : 0 : case RTE_TABLEFUNC:
483 : 0 : sub_action->hasSubLinks =
484 : 0 : checkExprHasSubLink((Node *) rte->tablefunc);
485 : 0 : break;
6381 tgl@sss.pgh.pa.us 486 : 0 : case RTE_VALUES:
487 : 0 : sub_action->hasSubLinks =
488 : 0 : checkExprHasSubLink((Node *) rte->values_lists);
489 : 0 : break;
6381 tgl@sss.pgh.pa.us 490 :CBC 3 : default:
491 : : /* other RTE types don't contain bare expressions */
492 : 3 : break;
493 : : }
1006 494 : 24 : sub_action->hasSubLinks |=
495 : 24 : checkExprHasSubLink((Node *) rte->securityQuals);
6381 496 [ + + ]: 24 : if (sub_action->hasSubLinks)
6121 bruce@momjian.us 497 : 3 : break; /* no need to keep scanning rtable */
498 : : }
499 : : }
500 : :
501 : : /*
502 : : * Also, we might have absorbed some RTEs with RLS conditions into the
503 : : * sub_action. If so, mark it as hasRowSecurity, whether or not those
504 : : * RTEs will be referenced after we finish rewriting. (Note: currently
505 : : * this is a no-op because RLS conditions aren't added till later, but it
506 : : * seems like good future-proofing to do this anyway.)
507 : : */
3412 tgl@sss.pgh.pa.us 508 : 708 : sub_action->hasRowSecurity |= parsetree->hasRowSecurity;
509 : :
510 : : /*
511 : : * Each rule action's jointree should be the main parsetree's jointree
512 : : * plus that rule's jointree, but usually *without* the original rtindex
513 : : * that we're replacing (if present, which it won't be for INSERT). Note
514 : : * that if the rule action refers to OLD, its jointree will add a
515 : : * reference to rt_index. If the rule action doesn't refer to OLD, but
516 : : * either the rule_qual or the user query quals do, then we need to keep
517 : : * the original rtindex in the jointree to provide data for the quals. We
518 : : * don't want the original rtindex to be joined twice, however, so avoid
519 : : * keeping it if the rule action mentions it.
520 : : *
521 : : * As above, the action's jointree must not share substructure with the
522 : : * main parsetree's.
523 : : */
8278 524 [ + + ]: 708 : if (sub_action->commandType != CMD_UTILITY)
525 : : {
526 : : bool keeporig;
527 : : List *newjointree;
528 : :
529 [ - + ]: 693 : Assert(sub_action->jointree != NULL);
9124 bruce@momjian.us 530 : 693 : keeporig = (!rangeTableEntry_used((Node *) sub_action->jointree,
531 [ + + + - ]: 1629 : rt_index, 0)) &&
9041 tgl@sss.pgh.pa.us 532 [ - + ]: 936 : (rangeTableEntry_used(rule_qual, rt_index, 0) ||
7456 bruce@momjian.us 533 : 468 : rangeTableEntry_used(parsetree->jointree->quals, rt_index, 0));
9178 tgl@sss.pgh.pa.us 534 : 693 : newjointree = adjustJoinTreeList(parsetree, !keeporig, rt_index);
8278 535 [ + + ]: 693 : if (newjointree != NIL)
536 : : {
537 : : /*
538 : : * If sub_action is a setop, manipulating its jointree will do no
539 : : * good at all, because the jointree is dummy. (Perhaps someday
540 : : * we could push the joining and quals down to the member
541 : : * statements of the setop?)
542 : : */
543 [ - + ]: 138 : if (sub_action->setOperations != NULL)
8269 tgl@sss.pgh.pa.us 544 [ # # ]:UBC 0 : ereport(ERROR,
545 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
546 : : errmsg("conditional UNION/INTERSECT/EXCEPT statements are not implemented")));
547 : :
8278 tgl@sss.pgh.pa.us 548 :CBC 276 : sub_action->jointree->fromlist =
7959 neilc@samurai.com 549 : 138 : list_concat(newjointree, sub_action->jointree->fromlist);
550 : :
551 : : /*
552 : : * There could have been some SubLinks in newjointree, in which
553 : : * case we'd better mark the sub_action correctly.
554 : : */
7417 tgl@sss.pgh.pa.us 555 [ + + + - ]: 138 : if (parsetree->hasSubLinks && !sub_action->hasSubLinks)
556 : 3 : sub_action->hasSubLinks =
557 : 3 : checkExprHasSubLink((Node *) newjointree);
558 : : }
559 : : }
560 : :
561 : : /*
562 : : * If the original query has any CTEs, copy them into the rule action. But
563 : : * we don't need them for a utility action.
564 : : */
5395 565 [ + + + - ]: 708 : if (parsetree->cteList != NIL && sub_action->commandType != CMD_UTILITY)
566 : : {
567 : : /*
568 : : * Annoying implementation restriction: because CTEs are identified by
569 : : * name within a cteList, we can't merge a CTE from the original query
570 : : * if it has the same name as any CTE in the rule action.
571 : : *
572 : : * This could possibly be fixed by using some sort of internally
573 : : * generated ID, instead of names, to link CTE RTEs to their CTEs.
574 : : * However, decompiling the results would be quite confusing; note the
575 : : * merge of hasRecursive flags below, which could change the apparent
576 : : * semantics of such redundantly-named CTEs.
577 : : */
578 [ + - + + : 36 : foreach(lc, parsetree->cteList)
+ + ]
579 : : {
580 : 18 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
581 : : ListCell *lc2;
582 : :
583 [ + + + + : 21 : foreach(lc2, sub_action->cteList)
+ + ]
584 : : {
585 : 3 : CommonTableExpr *cte2 = (CommonTableExpr *) lfirst(lc2);
586 : :
587 [ - + ]: 3 : if (strcmp(cte->ctename, cte2->ctename) == 0)
5395 tgl@sss.pgh.pa.us 588 [ # # ]:UBC 0 : ereport(ERROR,
589 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
590 : : errmsg("WITH query name \"%s\" appears in both a rule action and the query being rewritten",
591 : : cte->ctename)));
592 : : }
593 : : }
594 : :
595 : : /*
596 : : * OK, it's safe to combine the CTE lists. Beware that RewriteQuery
597 : : * knows we concatenate the lists in this order.
598 : : */
5395 tgl@sss.pgh.pa.us 599 :CBC 18 : sub_action->cteList = list_concat(sub_action->cteList,
600 : 18 : copyObject(parsetree->cteList));
601 : : /* ... and don't forget about the associated flags */
1649 602 : 18 : sub_action->hasRecursive |= parsetree->hasRecursive;
603 : 18 : sub_action->hasModifyingCTE |= parsetree->hasModifyingCTE;
604 : :
605 : : /*
606 : : * If rule_action is different from sub_action (i.e., the rule action
607 : : * is an INSERT...SELECT), then we might have just added some
608 : : * data-modifying CTEs that are not at the top query level. This is
609 : : * disallowed by the parser and we mustn't generate such trees here
610 : : * either, so throw an error.
611 : : *
612 : : * Conceivably such cases could be supported by attaching the original
613 : : * query's CTEs to rule_action not sub_action. But to do that, we'd
614 : : * have to increment ctelevelsup in RTEs and SubLinks copied from the
615 : : * original query. For now, it doesn't seem worth the trouble.
616 : : */
617 [ + + + + ]: 18 : if (sub_action->hasModifyingCTE && rule_action != sub_action)
618 [ + - ]: 3 : ereport(ERROR,
619 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
620 : : errmsg("INSERT ... SELECT rule actions are not supported for queries having data-modifying statements in WITH")));
621 : : }
622 : :
623 : : /*
624 : : * Event Qualification forces copying of parsetree and splitting into two
625 : : * queries one w/rule_qual, one w/NOT rule_qual. Also add user query qual
626 : : * onto rule action
627 : : */
9041 628 : 705 : AddQual(sub_action, rule_qual);
629 : :
9231 630 : 705 : AddQual(sub_action, parsetree->jointree->quals);
631 : :
632 : : /*
633 : : * Rewrite new.attribute with right hand side of target-list entry for
634 : : * appropriate field name in insert/update.
635 : : *
636 : : * KLUGE ALERT: since ReplaceVarsFromTargetList returns a mutated copy, we
637 : : * can't just apply it to sub_action; we have to remember to update the
638 : : * sublink inside rule_action, too.
639 : : */
7890 640 [ + + + + ]: 705 : if ((event == CMD_INSERT || event == CMD_UPDATE) &&
641 [ + + ]: 615 : sub_action->commandType != CMD_UTILITY)
642 : : {
643 : : sub_action = (Query *)
4875 644 [ + + ]: 1200 : ReplaceVarsFromTargetList((Node *) sub_action,
645 : : new_varno,
646 : : 0,
647 : 600 : rt_fetch(new_varno, sub_action->rtable),
648 : : parsetree->targetList,
649 : : sub_action->resultRelation,
650 : : (event == CMD_UPDATE) ?
651 : : REPLACEVARS_CHANGE_VARNO :
652 : : REPLACEVARS_SUBSTITUTE_NULL,
653 : : current_varno,
654 : : NULL);
9231 655 [ + + ]: 600 : if (sub_action_ptr)
656 : 27 : *sub_action_ptr = sub_action;
657 : : else
9041 658 : 573 : rule_action = sub_action;
659 : : }
660 : :
661 : : /*
662 : : * If rule_action is INSERT .. ON CONFLICT DO SELECT, the parser should
663 : : * have verified that it has a RETURNING clause, but we must also check
664 : : * that the triggering query has a RETURNING clause.
665 : : */
31 dean.a.rasheed@gmail 666 [ + + ]:GNC 705 : if (rule_action->onConflict &&
667 [ + + ]: 39 : rule_action->onConflict->action == ONCONFLICT_SELECT &&
668 [ + - + + ]: 15 : (!rule_action->returningList || !parsetree->returningList))
669 [ + - ]: 3 : ereport(ERROR,
670 : : errcode(ERRCODE_SYNTAX_ERROR),
671 : : errmsg("ON CONFLICT DO SELECT requires a RETURNING clause"),
672 : : errdetail("A rule action is INSERT ... ON CONFLICT DO SELECT, which requires a RETURNING clause."));
673 : :
674 : : /*
675 : : * If rule_action has a RETURNING clause, then either throw it away if the
676 : : * triggering query has no RETURNING clause, or rewrite it to emit what
677 : : * the triggering query's RETURNING clause asks for. Throw an error if
678 : : * more than one rule has a RETURNING clause.
679 : : */
7134 tgl@sss.pgh.pa.us 680 [ + + ]:CBC 702 : if (!parsetree->returningList)
681 : 612 : rule_action->returningList = NIL;
682 [ + + ]: 90 : else if (rule_action->returningList)
683 : : {
684 [ - + ]: 84 : if (*returning_flag)
7134 tgl@sss.pgh.pa.us 685 [ # # ]:UBC 0 : ereport(ERROR,
686 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
687 : : errmsg("cannot have RETURNING lists in multiple rules")));
7134 tgl@sss.pgh.pa.us 688 :CBC 84 : *returning_flag = true;
689 : 84 : rule_action->returningList = (List *)
4875 690 : 84 : ReplaceVarsFromTargetList((Node *) parsetree->returningList,
691 : : parsetree->resultRelation,
692 : : 0,
693 : 84 : rt_fetch(parsetree->resultRelation,
694 : : parsetree->rtable),
695 : : rule_action->returningList,
696 : : rule_action->resultRelation,
697 : : REPLACEVARS_REPORT_ERROR,
698 : : 0,
699 : : &rule_action->hasSubLinks);
700 : :
701 : : /* use triggering query's aliases for OLD and NEW in RETURNING list */
423 dean.a.rasheed@gmail 702 : 84 : rule_action->returningOldAlias = parsetree->returningOldAlias;
703 : 84 : rule_action->returningNewAlias = parsetree->returningNewAlias;
704 : :
705 : : /*
706 : : * There could have been some SubLinks in parsetree's returningList,
707 : : * in which case we'd better mark the rule_action correctly.
708 : : */
6381 tgl@sss.pgh.pa.us 709 [ - + - - ]: 84 : if (parsetree->hasSubLinks && !rule_action->hasSubLinks)
6381 tgl@sss.pgh.pa.us 710 :UBC 0 : rule_action->hasSubLinks =
6121 bruce@momjian.us 711 : 0 : checkExprHasSubLink((Node *) rule_action->returningList);
712 : : }
713 : :
9041 tgl@sss.pgh.pa.us 714 :CBC 702 : return rule_action;
715 : : }
716 : :
717 : : /*
718 : : * Copy the query's jointree list, and optionally attempt to remove any
719 : : * occurrence of the given rt_index as a top-level join item (we do not look
720 : : * for it within join items; this is OK because we are only expecting to find
721 : : * it as an UPDATE or DELETE target relation, which will be at the top level
722 : : * of the join). Returns modified jointree list --- this is a separate copy
723 : : * sharing no nodes with the original.
724 : : */
725 : : static List *
9178 726 : 693 : adjustJoinTreeList(Query *parsetree, bool removert, int rt_index)
727 : : {
9042 728 : 693 : List *newjointree = copyObject(parsetree->jointree->fromlist);
729 : : ListCell *l;
730 : :
9178 731 [ + - ]: 693 : if (removert)
732 : : {
7963 neilc@samurai.com 733 [ + + + + : 813 : foreach(l, newjointree)
+ + ]
734 : : {
735 : 372 : RangeTblRef *rtr = lfirst(l);
736 : :
8489 tgl@sss.pgh.pa.us 737 [ + - ]: 372 : if (IsA(rtr, RangeTblRef) &&
738 [ + + ]: 372 : rtr->rtindex == rt_index)
739 : : {
1970 drowley@postgresql.o 740 : 252 : newjointree = foreach_delete_current(newjointree, l);
9178 tgl@sss.pgh.pa.us 741 : 252 : break;
742 : : }
743 : : }
744 : : }
9315 745 : 693 : return newjointree;
746 : : }
747 : :
748 : :
749 : : /*
750 : : * rewriteTargetListIU - rewrite INSERT/UPDATE targetlist into standard form
751 : : *
752 : : * This has the following responsibilities:
753 : : *
754 : : * 1. For an INSERT, add tlist entries to compute default values for any
755 : : * attributes that have defaults and are not assigned to in the given tlist.
756 : : * (We do not insert anything for default-less attributes, however. The
757 : : * planner will later insert NULLs for them, but there's no reason to slow
758 : : * down rewriter processing with extra tlist nodes.) Also, for both INSERT
759 : : * and UPDATE, replace explicit DEFAULT specifications with column default
760 : : * expressions.
761 : : *
762 : : * 2. Merge multiple entries for the same target attribute, or declare error
763 : : * if we can't. Multiple entries are only allowed for INSERT/UPDATE of
764 : : * portions of an array or record field, for example
765 : : * UPDATE table SET foo[2] = 42, foo[4] = 43;
766 : : * We can merge such operations into a single assignment op. Essentially,
767 : : * the expression we want to produce in this case is like
768 : : * foo = array_set_element(array_set_element(foo, 2, 42), 4, 43)
769 : : *
770 : : * 3. Sort the tlist into standard order: non-junk fields in order by resno,
771 : : * then junk fields (these in no particular order).
772 : : *
773 : : * We must do items 1 and 2 before firing rewrite rules, else rewritten
774 : : * references to NEW.foo will produce wrong or incomplete results. Item 3
775 : : * is not needed for rewriting, but it is helpful for the planner, and we
776 : : * can do it essentially for free while handling the other items.
777 : : *
778 : : * If values_rte is non-NULL (i.e., we are doing a multi-row INSERT using
779 : : * values from a VALUES RTE), we populate *unused_values_attrnos with the
780 : : * attribute numbers of any unused columns from the VALUES RTE. This can
781 : : * happen for identity and generated columns whose targetlist entries are
782 : : * replaced with generated expressions (if INSERT ... OVERRIDING USER VALUE is
783 : : * used, or all the values to be inserted are DEFAULT). This information is
784 : : * required by rewriteValuesRTE() to handle any DEFAULT items in the unused
785 : : * columns. The caller must have initialized *unused_values_attrnos to NULL.
786 : : */
787 : : static List *
3964 andres@anarazel.de 788 : 44193 : rewriteTargetListIU(List *targetList,
789 : : CmdType commandType,
790 : : OverridingKind override,
791 : : Relation target_relation,
792 : : RangeTblEntry *values_rte,
793 : : int values_rte_index,
794 : : Bitmapset **unused_values_attrnos)
795 : : {
796 : : TargetEntry **new_tles;
8745 tgl@sss.pgh.pa.us 797 : 44193 : List *new_tlist = NIL;
7659 798 : 44193 : List *junk_tlist = NIL;
799 : : Form_pg_attribute att_tup;
800 : : int attrno,
801 : : next_junk_attrno,
802 : : numattrs;
803 : : ListCell *temp;
1939 804 : 44193 : Bitmapset *default_only_cols = NULL;
805 : :
806 : : /*
807 : : * We process the normal (non-junk) attributes by scanning the input tlist
808 : : * once and transferring TLEs into an array, then scanning the array to
809 : : * build an output tlist. This avoids O(N^2) behavior for large numbers
810 : : * of attributes.
811 : : *
812 : : * Junk attributes are tossed into a separate list during the same tlist
813 : : * scan, then appended to the reconstructed tlist.
814 : : */
8745 815 : 44193 : numattrs = RelationGetNumberOfAttributes(target_relation);
7659 816 : 44193 : new_tles = (TargetEntry **) palloc0(numattrs * sizeof(TargetEntry *));
817 : 44193 : next_junk_attrno = numattrs + 1;
818 : :
3964 andres@anarazel.de 819 [ + + + + : 122502 : foreach(temp, targetList)
+ + ]
820 : : {
7659 tgl@sss.pgh.pa.us 821 : 78318 : TargetEntry *old_tle = (TargetEntry *) lfirst(temp);
822 : :
7648 823 [ + + ]: 78318 : if (!old_tle->resjunk)
824 : : {
825 : : /* Normal attr: stash it into new_tles[] */
826 : 78252 : attrno = old_tle->resno;
7659 827 [ + - - + ]: 78252 : if (attrno < 1 || attrno > numattrs)
7659 tgl@sss.pgh.pa.us 828 [ # # ]:UBC 0 : elog(ERROR, "bogus resno %d in targetlist", attrno);
3129 andres@anarazel.de 829 :CBC 78252 : att_tup = TupleDescAttr(target_relation->rd_att, attrno - 1);
830 : :
831 : : /* We can (and must) ignore deleted attributes */
7659 tgl@sss.pgh.pa.us 832 [ - + ]: 78252 : if (att_tup->attisdropped)
7659 tgl@sss.pgh.pa.us 833 :UBC 0 : continue;
834 : :
835 : : /* Merge with any prior assignment to same attribute */
7659 tgl@sss.pgh.pa.us 836 :CBC 78243 : new_tles[attrno - 1] =
837 : 78252 : process_matched_tle(old_tle,
838 : 78252 : new_tles[attrno - 1],
839 : 78252 : NameStr(att_tup->attname));
840 : : }
841 : : else
842 : : {
843 : : /*
844 : : * Copy all resjunk tlist entries to junk_tlist, and assign them
845 : : * resnos above the last real resno.
846 : : *
847 : : * Typical junk entries include ORDER BY or GROUP BY expressions
848 : : * (are these actually possible in an INSERT or UPDATE?), system
849 : : * attribute references, etc.
850 : : */
851 : :
852 : : /* Get the resno right, but don't copy unnecessarily */
7648 853 [ - + ]: 66 : if (old_tle->resno != next_junk_attrno)
854 : : {
7648 tgl@sss.pgh.pa.us 855 :UBC 0 : old_tle = flatCopyTargetEntry(old_tle);
856 : 0 : old_tle->resno = next_junk_attrno;
857 : : }
7659 tgl@sss.pgh.pa.us 858 :CBC 66 : junk_tlist = lappend(junk_tlist, old_tle);
859 : 66 : next_junk_attrno++;
860 : : }
861 : : }
862 : :
863 [ + + ]: 198414 : for (attrno = 1; attrno <= numattrs; attrno++)
864 : : {
865 : 154329 : TargetEntry *new_tle = new_tles[attrno - 1];
866 : : bool apply_default;
867 : :
3129 andres@anarazel.de 868 : 154329 : att_tup = TupleDescAttr(target_relation->rd_att, attrno - 1);
869 : :
870 : : /* We can (and must) ignore deleted attributes */
7659 tgl@sss.pgh.pa.us 871 [ + + ]: 154329 : if (att_tup->attisdropped)
872 : 514 : continue;
873 : :
874 : : /*
875 : : * Handle the two cases where we need to insert a default expression:
876 : : * it's an INSERT and there's no tlist entry for the column, or the
877 : : * tlist entry is a DEFAULT placeholder node.
878 : : */
3265 peter_e@gmx.net 879 [ + + + + : 231862 : apply_default = ((new_tle == NULL && commandType == CMD_INSERT) ||
+ + ]
3189 tgl@sss.pgh.pa.us 880 [ + - + + ]: 78047 : (new_tle && new_tle->expr && IsA(new_tle->expr, SetToDefault)));
881 : :
3265 peter_e@gmx.net 882 [ + + ]: 153815 : if (commandType == CMD_INSERT)
883 : : {
1939 tgl@sss.pgh.pa.us 884 : 78855 : int values_attrno = 0;
885 : :
886 : : /* Source attribute number for values that come from a VALUES RTE */
887 [ + + + + : 78855 : if (values_rte && new_tle && IsA(new_tle->expr, Var))
+ + ]
888 : : {
889 : 4748 : Var *var = (Var *) new_tle->expr;
890 : :
891 [ + - ]: 4748 : if (var->varno == values_rte_index)
892 : 4748 : values_attrno = var->varattno;
893 : : }
894 : :
895 : : /*
896 : : * Can only insert DEFAULT into GENERATED ALWAYS identity columns,
897 : : * unless either OVERRIDING USER VALUE or OVERRIDING SYSTEM VALUE
898 : : * is specified.
899 : : */
3265 peter_e@gmx.net 900 [ + + + + ]: 78855 : if (att_tup->attidentity == ATTRIBUTE_IDENTITY_ALWAYS && !apply_default)
901 : : {
2175 peter@eisentraut.org 902 [ + + ]: 71 : if (override == OVERRIDING_USER_VALUE)
903 : 21 : apply_default = true;
904 [ + + ]: 50 : else if (override != OVERRIDING_SYSTEM_VALUE)
905 : : {
906 : : /*
907 : : * If this column's values come from a VALUES RTE, test
908 : : * whether it contains only SetToDefault items. Since the
909 : : * VALUES list might be quite large, we arrange to only
910 : : * scan it once.
911 : : */
1939 tgl@sss.pgh.pa.us 912 [ + + ]: 26 : if (values_attrno != 0)
913 : : {
914 [ + - ]: 14 : if (default_only_cols == NULL)
915 : 14 : default_only_cols = findDefaultOnlyColumns(values_rte);
916 : :
917 [ + + ]: 14 : if (bms_is_member(values_attrno, default_only_cols))
918 : 5 : apply_default = true;
919 : : }
920 : :
921 [ + + ]: 26 : if (!apply_default)
922 [ + - ]: 21 : ereport(ERROR,
923 : : (errcode(ERRCODE_GENERATED_ALWAYS),
924 : : errmsg("cannot insert a non-DEFAULT value into column \"%s\"",
925 : : NameStr(att_tup->attname)),
926 : : errdetail("Column \"%s\" is an identity column defined as GENERATED ALWAYS.",
927 : : NameStr(att_tup->attname)),
928 : : errhint("Use OVERRIDING SYSTEM VALUE to override.")));
929 : : }
930 : : }
931 : :
932 : : /*
933 : : * Although inserting into a GENERATED BY DEFAULT identity column
934 : : * is allowed, apply the default if OVERRIDING USER VALUE is
935 : : * specified.
936 : : */
937 [ + + + + ]: 78834 : if (att_tup->attidentity == ATTRIBUTE_IDENTITY_BY_DEFAULT &&
938 : : override == OVERRIDING_USER_VALUE)
3265 peter_e@gmx.net 939 : 9 : apply_default = true;
940 : :
941 : : /*
942 : : * Can only insert DEFAULT into generated columns. (The
943 : : * OVERRIDING clause does not apply to generated columns, so we
944 : : * don't consider it here.)
945 : : */
2542 peter@eisentraut.org 946 [ + + + + ]: 78834 : if (att_tup->attgenerated && !apply_default)
947 : : {
948 : : /*
949 : : * If this column's values come from a VALUES RTE, test
950 : : * whether it contains only SetToDefault items, as above.
951 : : */
1939 tgl@sss.pgh.pa.us 952 [ + + ]: 85 : if (values_attrno != 0)
953 : : {
954 [ + - ]: 58 : if (default_only_cols == NULL)
955 : 58 : default_only_cols = findDefaultOnlyColumns(values_rte);
956 : :
957 [ + + ]: 58 : if (bms_is_member(values_attrno, default_only_cols))
958 : 16 : apply_default = true;
959 : : }
960 : :
961 [ + + ]: 85 : if (!apply_default)
962 [ + - ]: 69 : ereport(ERROR,
963 : : (errcode(ERRCODE_GENERATED_ALWAYS),
964 : : errmsg("cannot insert a non-DEFAULT value into column \"%s\"",
965 : : NameStr(att_tup->attname)),
966 : : errdetail("Column \"%s\" is a generated column.",
967 : : NameStr(att_tup->attname))));
968 : : }
969 : :
970 : : /*
971 : : * For an INSERT from a VALUES RTE, return the attribute numbers
972 : : * of any VALUES columns that will no longer be used (due to the
973 : : * targetlist entry being replaced by a default expression).
974 : : */
975 [ + + + + : 78765 : if (values_attrno != 0 && apply_default && unused_values_attrnos)
+ - ]
976 : 33 : *unused_values_attrnos = bms_add_member(*unused_values_attrnos,
977 : : values_attrno);
978 : : }
979 : :
980 : : /*
981 : : * Updates to identity and generated columns follow the same rules as
982 : : * above, except that UPDATE doesn't admit OVERRIDING clauses. Also,
983 : : * the source can't be a VALUES RTE, so we needn't consider that.
984 : : */
3265 peter_e@gmx.net 985 [ + + ]: 153725 : if (commandType == CMD_UPDATE)
986 : : {
1938 tgl@sss.pgh.pa.us 987 [ + + + - ]: 74960 : if (att_tup->attidentity == ATTRIBUTE_IDENTITY_ALWAYS &&
988 [ + + ]: 6 : new_tle && !apply_default)
3265 peter_e@gmx.net 989 [ + - ]: 3 : ereport(ERROR,
990 : : (errcode(ERRCODE_GENERATED_ALWAYS),
991 : : errmsg("column \"%s\" can only be updated to DEFAULT",
992 : : NameStr(att_tup->attname)),
993 : : errdetail("Column \"%s\" is an identity column defined as GENERATED ALWAYS.",
994 : : NameStr(att_tup->attname))));
995 : :
2542 peter@eisentraut.org 996 [ + + + + : 74957 : if (att_tup->attgenerated && new_tle && !apply_default)
+ + ]
997 [ + - ]: 6 : ereport(ERROR,
998 : : (errcode(ERRCODE_GENERATED_ALWAYS),
999 : : errmsg("column \"%s\" can only be updated to DEFAULT",
1000 : : NameStr(att_tup->attname)),
1001 : : errdetail("Column \"%s\" is a generated column.",
1002 : : NameStr(att_tup->attname))));
1003 : : }
1004 : :
1005 [ + + ]: 153716 : if (att_tup->attgenerated)
1006 : : {
1007 : : /*
1008 : : * virtual generated column stores a null value; stored generated
1009 : : * column will be fixed in executor
1010 : : */
1011 : 863 : new_tle = NULL;
1012 : : }
1013 [ + + ]: 152853 : else if (apply_default)
1014 : : {
1015 : : Node *new_expr;
1016 : :
2963 peter_e@gmx.net 1017 : 12512 : new_expr = build_column_default(target_relation, attrno);
1018 : :
1019 : : /*
1020 : : * If there is no default (ie, default is effectively NULL), we
1021 : : * can omit the tlist entry in the INSERT case, since the planner
1022 : : * can insert a NULL for itself, and there's no point in spending
1023 : : * any more rewriter cycles on the entry. But in the UPDATE case
1024 : : * we've got to explicitly set the column to NULL.
1025 : : */
8291 tgl@sss.pgh.pa.us 1026 [ + + ]: 12512 : if (!new_expr)
1027 : : {
1028 [ + + ]: 9552 : if (commandType == CMD_INSERT)
1029 : 9540 : new_tle = NULL;
1030 : : else
410 1031 : 12 : new_expr = coerce_null_to_domain(att_tup->atttypid,
1032 : : att_tup->atttypmod,
1033 : : att_tup->attcollation,
1034 : 12 : att_tup->attlen,
1035 : 12 : att_tup->attbyval);
1036 : : }
1037 : :
8745 1038 [ + + ]: 12512 : if (new_expr)
7648 1039 : 2972 : new_tle = makeTargetEntry((Expr *) new_expr,
1040 : : attrno,
1041 : 2972 : pstrdup(NameStr(att_tup->attname)),
1042 : : false);
1043 : : }
1044 : :
8745 1045 [ + + ]: 153716 : if (new_tle)
1046 : 80523 : new_tlist = lappend(new_tlist, new_tle);
1047 : : }
1048 : :
7659 1049 : 44085 : pfree(new_tles);
1050 : :
3964 andres@anarazel.de 1051 : 44085 : return list_concat(new_tlist, junk_tlist);
1052 : : }
1053 : :
1054 : :
1055 : : /*
1056 : : * Convert a matched TLE from the original tlist into a correct new TLE.
1057 : : *
1058 : : * This routine detects and handles multiple assignments to the same target
1059 : : * attribute. (The attribute name is needed only for error messages.)
1060 : : */
1061 : : static TargetEntry *
8745 tgl@sss.pgh.pa.us 1062 : 78252 : process_matched_tle(TargetEntry *src_tle,
1063 : : TargetEntry *prior_tle,
1064 : : const char *attrName)
1065 : : {
1066 : : TargetEntry *result;
3169 1067 : 78252 : CoerceToDomain *coerce_expr = NULL;
1068 : : Node *src_expr;
1069 : : Node *prior_expr;
1070 : : Node *src_input;
1071 : : Node *prior_input;
1072 : : Node *priorbottom;
1073 : : Node *newexpr;
1074 : :
8745 1075 [ + + ]: 78252 : if (prior_tle == NULL)
1076 : : {
1077 : : /*
1078 : : * Normal case where this is the first assignment to the attribute.
1079 : : */
1080 : 78083 : return src_tle;
1081 : : }
1082 : :
1083 : : /*----------
1084 : : * Multiple assignments to same attribute. Allow only if all are
1085 : : * FieldStore or SubscriptingRef assignment operations. This is a bit
1086 : : * tricky because what we may actually be looking at is a nest of
1087 : : * such nodes; consider
1088 : : * UPDATE tab SET col.fld1.subfld1 = x, col.fld2.subfld2 = y
1089 : : * The two expressions produced by the parser will look like
1090 : : * FieldStore(col, fld1, FieldStore(placeholder, subfld1, x))
1091 : : * FieldStore(col, fld2, FieldStore(placeholder, subfld2, y))
1092 : : * However, we can ignore the substructure and just consider the top
1093 : : * FieldStore or SubscriptingRef from each assignment, because it works to
1094 : : * combine these as
1095 : : * FieldStore(FieldStore(col, fld1,
1096 : : * FieldStore(placeholder, subfld1, x)),
1097 : : * fld2, FieldStore(placeholder, subfld2, y))
1098 : : * Note the leftmost expression goes on the inside so that the
1099 : : * assignments appear to occur left-to-right.
1100 : : *
1101 : : * For FieldStore, instead of nesting we can generate a single
1102 : : * FieldStore with multiple target fields. We must nest when
1103 : : * SubscriptingRefs are involved though.
1104 : : *
1105 : : * As a further complication, the destination column might be a domain,
1106 : : * resulting in each assignment containing a CoerceToDomain node over a
1107 : : * FieldStore or SubscriptingRef. These should have matching target
1108 : : * domains, so we strip them and reconstitute a single CoerceToDomain over
1109 : : * the combined FieldStore/SubscriptingRef nodes. (Notice that this has
1110 : : * the result that the domain's checks are applied only after we do all
1111 : : * the field or element updates, not after each one. This is desirable.)
1112 : : *----------
1113 : : */
7949 1114 : 169 : src_expr = (Node *) src_tle->expr;
1115 : 169 : prior_expr = (Node *) prior_tle->expr;
1116 : :
3169 1117 [ + - + + : 169 : if (src_expr && IsA(src_expr, CoerceToDomain) &&
+ - ]
1118 [ + - ]: 81 : prior_expr && IsA(prior_expr, CoerceToDomain) &&
1119 : 81 : ((CoerceToDomain *) src_expr)->resulttype ==
1120 [ + - ]: 81 : ((CoerceToDomain *) prior_expr)->resulttype)
1121 : : {
1122 : : /* we assume without checking that resulttypmod/resultcollid match */
1123 : 81 : coerce_expr = (CoerceToDomain *) src_expr;
1124 : 81 : src_expr = (Node *) ((CoerceToDomain *) src_expr)->arg;
1125 : 81 : prior_expr = (Node *) ((CoerceToDomain *) prior_expr)->arg;
1126 : : }
1127 : :
7949 1128 : 169 : src_input = get_assignment_input(src_expr);
1129 : 169 : prior_input = get_assignment_input(prior_expr);
1130 [ + + + - ]: 169 : if (src_input == NULL ||
1131 [ - + ]: 160 : prior_input == NULL ||
1132 : 160 : exprType(src_expr) != exprType(prior_expr))
8269 1133 [ + - ]: 9 : ereport(ERROR,
1134 : : (errcode(ERRCODE_SYNTAX_ERROR),
1135 : : errmsg("multiple assignments to same column \"%s\"",
1136 : : attrName)));
1137 : :
1138 : : /*
1139 : : * Prior TLE could be a nest of assignments if we do this more than once.
1140 : : */
7949 1141 : 160 : priorbottom = prior_input;
1142 : : for (;;)
1143 : 21 : {
7868 bruce@momjian.us 1144 : 181 : Node *newbottom = get_assignment_input(priorbottom);
1145 : :
7949 tgl@sss.pgh.pa.us 1146 [ + + ]: 181 : if (newbottom == NULL)
1147 : 160 : break; /* found the original Var reference */
1148 : 21 : priorbottom = newbottom;
1149 : : }
1150 [ - + ]: 160 : if (!equal(priorbottom, src_input))
8269 tgl@sss.pgh.pa.us 1151 [ # # ]:UBC 0 : ereport(ERROR,
1152 : : (errcode(ERRCODE_SYNTAX_ERROR),
1153 : : errmsg("multiple assignments to same column \"%s\"",
1154 : : attrName)));
1155 : :
1156 : : /*
1157 : : * Looks OK to nest 'em.
1158 : : */
7949 tgl@sss.pgh.pa.us 1159 [ + + ]:CBC 160 : if (IsA(src_expr, FieldStore))
1160 : : {
7868 bruce@momjian.us 1161 : 63 : FieldStore *fstore = makeNode(FieldStore);
1162 : :
7949 tgl@sss.pgh.pa.us 1163 [ + - ]: 63 : if (IsA(prior_expr, FieldStore))
1164 : : {
1165 : : /* combine the two */
1166 : 63 : memcpy(fstore, prior_expr, sizeof(FieldStore));
1167 : 63 : fstore->newvals =
2407 1168 : 63 : list_concat_copy(((FieldStore *) prior_expr)->newvals,
1169 : 63 : ((FieldStore *) src_expr)->newvals);
7949 1170 : 63 : fstore->fieldnums =
2407 1171 : 63 : list_concat_copy(((FieldStore *) prior_expr)->fieldnums,
1172 : 63 : ((FieldStore *) src_expr)->fieldnums);
1173 : : }
1174 : : else
1175 : : {
1176 : : /* general case, just nest 'em */
7949 tgl@sss.pgh.pa.us 1177 :UBC 0 : memcpy(fstore, src_expr, sizeof(FieldStore));
1178 : 0 : fstore->arg = (Expr *) prior_expr;
1179 : : }
7949 tgl@sss.pgh.pa.us 1180 :CBC 63 : newexpr = (Node *) fstore;
1181 : : }
2599 alvherre@alvh.no-ip. 1182 [ + - ]: 97 : else if (IsA(src_expr, SubscriptingRef))
1183 : : {
1184 : 97 : SubscriptingRef *sbsref = makeNode(SubscriptingRef);
1185 : :
1186 : 97 : memcpy(sbsref, src_expr, sizeof(SubscriptingRef));
1187 : 97 : sbsref->refexpr = (Expr *) prior_expr;
1188 : 97 : newexpr = (Node *) sbsref;
1189 : : }
1190 : : else
1191 : : {
6982 bruce@momjian.us 1192 [ # # ]:UBC 0 : elog(ERROR, "cannot happen");
1193 : : newexpr = NULL;
1194 : : }
1195 : :
3169 tgl@sss.pgh.pa.us 1196 [ + + ]:CBC 160 : if (coerce_expr)
1197 : : {
1198 : : /* put back the CoerceToDomain */
1199 : 81 : CoerceToDomain *newcoerce = makeNode(CoerceToDomain);
1200 : :
1201 : 81 : memcpy(newcoerce, coerce_expr, sizeof(CoerceToDomain));
1202 : 81 : newcoerce->arg = (Expr *) newexpr;
1203 : 81 : newexpr = (Node *) newcoerce;
1204 : : }
1205 : :
7648 1206 : 160 : result = flatCopyTargetEntry(src_tle);
1207 : 160 : result->expr = (Expr *) newexpr;
1208 : 160 : return result;
1209 : : }
1210 : :
1211 : : /*
1212 : : * If node is an assignment node, return its input; else return NULL
1213 : : */
1214 : : static Node *
7949 1215 : 519 : get_assignment_input(Node *node)
1216 : : {
1217 [ - + ]: 519 : if (node == NULL)
7949 tgl@sss.pgh.pa.us 1218 :UBC 0 : return NULL;
7949 tgl@sss.pgh.pa.us 1219 [ + + ]:CBC 519 : if (IsA(node, FieldStore))
1220 : : {
1221 : 126 : FieldStore *fstore = (FieldStore *) node;
1222 : :
1223 : 126 : return (Node *) fstore->arg;
1224 : : }
2599 alvherre@alvh.no-ip. 1225 [ + + ]: 393 : else if (IsA(node, SubscriptingRef))
1226 : : {
1227 : 215 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1228 : :
1229 [ - + ]: 215 : if (sbsref->refassgnexpr == NULL)
7949 tgl@sss.pgh.pa.us 1230 :UBC 0 : return NULL;
1231 : :
2599 alvherre@alvh.no-ip. 1232 :CBC 215 : return (Node *) sbsref->refexpr;
1233 : : }
1234 : :
7949 tgl@sss.pgh.pa.us 1235 : 178 : return NULL;
1236 : : }
1237 : :
1238 : : /*
1239 : : * Make an expression tree for the default value for a column.
1240 : : *
1241 : : * If there is no default, return a NULL instead.
1242 : : */
1243 : : Node *
8745 1244 : 94415 : build_column_default(Relation rel, int attrno)
1245 : : {
1246 : 94415 : TupleDesc rd_att = rel->rd_att;
3129 andres@anarazel.de 1247 : 94415 : Form_pg_attribute att_tup = TupleDescAttr(rd_att, attrno - 1);
8745 tgl@sss.pgh.pa.us 1248 : 94415 : Oid atttype = att_tup->atttypid;
1249 : 94415 : int32 atttypmod = att_tup->atttypmod;
1250 : 94415 : Node *expr = NULL;
1251 : : Oid exprtype;
1252 : :
2963 peter_e@gmx.net 1253 [ + + ]: 94415 : if (att_tup->attidentity)
1254 : : {
1255 : 252 : NextValueExpr *nve = makeNode(NextValueExpr);
1256 : :
677 peter@eisentraut.org 1257 : 252 : nve->seqid = getIdentitySequence(rel, attrno, false);
2963 peter_e@gmx.net 1258 : 252 : nve->typeId = att_tup->atttypid;
1259 : :
1260 : 252 : return (Node *) nve;
1261 : : }
1262 : :
1263 : : /*
1264 : : * If relation has a default for this column, fetch that expression.
1265 : : */
1804 tgl@sss.pgh.pa.us 1266 [ + + ]: 94163 : if (att_tup->atthasdef)
1267 : : {
900 peter@eisentraut.org 1268 : 75246 : expr = TupleDescGetDefault(rd_att, attrno);
1804 tgl@sss.pgh.pa.us 1269 [ - + ]: 75246 : if (expr == NULL)
1804 tgl@sss.pgh.pa.us 1270 [ # # ]:UBC 0 : elog(ERROR, "default expression not found for attribute %d of relation \"%s\"",
1271 : : attrno, RelationGetRelationName(rel));
1272 : : }
1273 : :
1274 : : /*
1275 : : * No per-column default, so look for a default for the type itself. But
1276 : : * not for generated columns.
1277 : : */
2542 peter@eisentraut.org 1278 [ + + + - ]:CBC 94163 : if (expr == NULL && !att_tup->attgenerated)
8018 tgl@sss.pgh.pa.us 1279 : 18917 : expr = get_typdefault(atttype);
1280 : :
8745 1281 [ + + ]: 94163 : if (expr == NULL)
1282 : 18793 : return NULL; /* No default anywhere */
1283 : :
1284 : : /*
1285 : : * Make sure the value is coerced to the target column type; this will
1286 : : * generally be true already, but there seem to be some corner cases
1287 : : * involving domain defaults where it might not be true. This should match
1288 : : * the parser's processing of non-defaulted expressions --- see
1289 : : * transformAssignedExpr().
1290 : : */
1291 : 75370 : exprtype = exprType(expr);
1292 : :
8259 bruce@momjian.us 1293 : 75370 : expr = coerce_to_target_type(NULL, /* no UNKNOWN params here */
1294 : : expr, exprtype,
1295 : : atttype, atttypmod,
1296 : : COERCION_ASSIGNMENT,
1297 : : COERCE_IMPLICIT_CAST,
1298 : : -1);
8579 tgl@sss.pgh.pa.us 1299 [ - + ]: 75370 : if (expr == NULL)
8269 tgl@sss.pgh.pa.us 1300 [ # # ]:UBC 0 : ereport(ERROR,
1301 : : (errcode(ERRCODE_DATATYPE_MISMATCH),
1302 : : errmsg("column \"%s\" is of type %s"
1303 : : " but default expression is of type %s",
1304 : : NameStr(att_tup->attname),
1305 : : format_type_be(atttype),
1306 : : format_type_be(exprtype)),
1307 : : errhint("You will need to rewrite or cast the expression.")));
1308 : :
8745 tgl@sss.pgh.pa.us 1309 :CBC 75370 : return expr;
1310 : : }
1311 : :
1312 : :
1313 : : /* Does VALUES RTE contain any SetToDefault items? */
1314 : : static bool
7165 mail@joeconway.com 1315 : 2553 : searchForDefault(RangeTblEntry *rte)
1316 : : {
1317 : : ListCell *lc;
1318 : :
1319 [ + - + + : 10974 : foreach(lc, rte->values_lists)
+ + ]
1320 : : {
7102 bruce@momjian.us 1321 : 8574 : List *sublist = (List *) lfirst(lc);
1322 : : ListCell *lc2;
1323 : :
7165 mail@joeconway.com 1324 [ + - + + : 26281 : foreach(lc2, sublist)
+ + ]
1325 : : {
7102 bruce@momjian.us 1326 : 17860 : Node *col = (Node *) lfirst(lc2);
1327 : :
7165 mail@joeconway.com 1328 [ + + ]: 17860 : if (IsA(col, SetToDefault))
1329 : 153 : return true;
1330 : : }
1331 : : }
1332 : 2400 : return false;
1333 : : }
1334 : :
1335 : :
1336 : : /*
1337 : : * Search a VALUES RTE for columns that contain only SetToDefault items,
1338 : : * returning a Bitmapset containing the attribute numbers of any such columns.
1339 : : */
1340 : : static Bitmapset *
1939 tgl@sss.pgh.pa.us 1341 : 72 : findDefaultOnlyColumns(RangeTblEntry *rte)
1342 : : {
1343 : 72 : Bitmapset *default_only_cols = NULL;
1344 : : ListCell *lc;
1345 : :
1346 [ + - + + : 132 : foreach(lc, rte->values_lists)
+ + ]
1347 : : {
1348 : 111 : List *sublist = (List *) lfirst(lc);
1349 : : ListCell *lc2;
1350 : : int i;
1351 : :
1352 [ + + ]: 111 : if (default_only_cols == NULL)
1353 : : {
1354 : : /* Populate the initial result bitmap from the first row */
1355 : 72 : i = 0;
1356 [ + - + + : 219 : foreach(lc2, sublist)
+ + ]
1357 : : {
1358 : 147 : Node *col = (Node *) lfirst(lc2);
1359 : :
1360 : 147 : i++;
1361 [ + + ]: 147 : if (IsA(col, SetToDefault))
1362 : 37 : default_only_cols = bms_add_member(default_only_cols, i);
1363 : : }
1364 : : }
1365 : : else
1366 : : {
1367 : : /* Update the result bitmap from this next row */
1368 : 39 : i = 0;
1369 [ + - + + : 123 : foreach(lc2, sublist)
+ + ]
1370 : : {
1371 : 84 : Node *col = (Node *) lfirst(lc2);
1372 : :
1373 : 84 : i++;
1374 [ + + ]: 84 : if (!IsA(col, SetToDefault))
1375 : 59 : default_only_cols = bms_del_member(default_only_cols, i);
1376 : : }
1377 : : }
1378 : :
1379 : : /*
1380 : : * If no column in the rows read so far contains only DEFAULT items,
1381 : : * we are done.
1382 : : */
1383 [ + + ]: 111 : if (bms_is_empty(default_only_cols))
1384 : 51 : break;
1385 : : }
1386 : :
1387 : 72 : return default_only_cols;
1388 : : }
1389 : :
1390 : :
1391 : : /*
1392 : : * When processing INSERT ... VALUES with a VALUES RTE (ie, multiple VALUES
1393 : : * lists), we have to replace any DEFAULT items in the VALUES lists with
1394 : : * the appropriate default expressions. The other aspects of targetlist
1395 : : * rewriting need be applied only to the query's targetlist proper.
1396 : : *
1397 : : * For an auto-updatable view, each DEFAULT item in the VALUES list is
1398 : : * replaced with the default from the view, if it has one. Otherwise it is
1399 : : * left untouched so that the underlying base relation's default can be
1400 : : * applied instead (when we later recurse to here after rewriting the query
1401 : : * to refer to the base relation instead of the view).
1402 : : *
1403 : : * For other types of relation, including rule- and trigger-updatable views,
1404 : : * all DEFAULT items are replaced, and if the target relation doesn't have a
1405 : : * default, the value is explicitly set to NULL.
1406 : : *
1407 : : * Also, if a DEFAULT item is found in a column mentioned in unused_cols,
1408 : : * it is explicitly set to NULL. This happens for columns in the VALUES RTE
1409 : : * whose corresponding targetlist entries have already been replaced with the
1410 : : * relation's default expressions, so that any values in those columns of the
1411 : : * VALUES RTE are no longer used. This can happen for identity and generated
1412 : : * columns (if INSERT ... OVERRIDING USER VALUE is used, or all the values to
1413 : : * be inserted are DEFAULT). In principle we could replace all entries in
1414 : : * such a column with NULL, whether DEFAULT or not; but it doesn't seem worth
1415 : : * the trouble.
1416 : : *
1417 : : * Note that we may have subscripted or field assignment targetlist entries,
1418 : : * as well as more complex expressions from already-replaced DEFAULT items if
1419 : : * we have recursed to here for an auto-updatable view. However, it ought to
1420 : : * be impossible for such entries to have DEFAULTs assigned to them, except
1421 : : * for unused columns, as described above --- we should only have to replace
1422 : : * DEFAULT items for targetlist entries that contain simple Vars referencing
1423 : : * the VALUES RTE, or which are no longer referred to by the targetlist.
1424 : : *
1425 : : * Returns true if all DEFAULT items were replaced, and false if some were
1426 : : * left untouched.
1427 : : */
1428 : : static bool
2569 dean.a.rasheed@gmail 1429 : 2553 : rewriteValuesRTE(Query *parsetree, RangeTblEntry *rte, int rti,
1430 : : Relation target_relation,
1431 : : Bitmapset *unused_cols)
1432 : : {
1433 : : List *newValues;
1434 : : ListCell *lc;
1435 : : bool isAutoUpdatableView;
1436 : : bool allReplaced;
1437 : : int numattrs;
1438 : : int *attrnos;
1439 : :
1440 : : /* Steps below are not sensible for non-INSERT queries */
1251 tgl@sss.pgh.pa.us 1441 [ - + ]: 2553 : Assert(parsetree->commandType == CMD_INSERT);
1442 [ - + ]: 2553 : Assert(rte->rtekind == RTE_VALUES);
1443 : :
1444 : : /*
1445 : : * Rebuilding all the lists is a pretty expensive proposition in a big
1446 : : * VALUES list, and it's a waste of time if there aren't any DEFAULT
1447 : : * placeholders. So first scan to see if there are any.
1448 : : */
1449 [ + + ]: 2553 : if (!searchForDefault(rte))
2580 dean.a.rasheed@gmail 1450 : 2400 : return true; /* nothing to do */
1451 : :
1452 : : /*
1453 : : * Scan the targetlist for entries referring to the VALUES RTE, and note
1454 : : * the target attributes. As noted above, we should only need to do this
1455 : : * for targetlist entries containing simple Vars --- nothing else in the
1456 : : * VALUES RTE should contain DEFAULT items (except possibly for unused
1457 : : * columns), and we complain if such a thing does occur.
1458 : : */
2569 1459 : 153 : numattrs = list_length(linitial(rte->values_lists));
1460 : 153 : attrnos = (int *) palloc0(numattrs * sizeof(int));
1461 : :
1462 [ + - + + : 617 : foreach(lc, parsetree->targetList)
+ + ]
1463 : : {
1464 : 464 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
1465 : :
1466 [ + + ]: 464 : if (IsA(tle->expr, Var))
1467 : : {
1468 : 396 : Var *var = (Var *) tle->expr;
1469 : :
1470 [ + - ]: 396 : if (var->varno == rti)
1471 : : {
1472 : 396 : int attrno = var->varattno;
1473 : :
1474 [ + - - + ]: 396 : Assert(attrno >= 1 && attrno <= numattrs);
1475 : 396 : attrnos[attrno - 1] = tle->resno;
1476 : : }
1477 : : }
1478 : : }
1479 : :
1480 : : /*
1481 : : * Check if the target relation is an auto-updatable view, in which case
1482 : : * unresolved defaults will be left untouched rather than being set to
1483 : : * NULL.
1484 : : */
2580 1485 : 153 : isAutoUpdatableView = false;
1251 tgl@sss.pgh.pa.us 1486 [ + + ]: 153 : if (target_relation->rd_rel->relkind == RELKIND_VIEW &&
745 dean.a.rasheed@gmail 1487 [ + + ]: 57 : !view_has_instead_trigger(target_relation, CMD_INSERT, NIL))
1488 : : {
1489 : : List *locks;
1490 : : bool hasUpdate;
1491 : : bool found;
1492 : : ListCell *l;
1493 : :
1494 : : /* Look for an unconditional DO INSTEAD rule */
1495 : 51 : locks = matchLocks(CMD_INSERT, target_relation,
1496 : : parsetree->resultRelation, parsetree, &hasUpdate);
1497 : :
2580 1498 : 51 : found = false;
1499 [ + + + + : 63 : foreach(l, locks)
+ + ]
1500 : : {
1501 : 18 : RewriteRule *rule_lock = (RewriteRule *) lfirst(l);
1502 : :
1503 [ + + ]: 18 : if (rule_lock->isInstead &&
1504 [ + - ]: 6 : rule_lock->qual == NULL)
1505 : : {
1506 : 6 : found = true;
1507 : 6 : break;
1508 : : }
1509 : : }
1510 : :
1511 : : /*
1512 : : * If we didn't find an unconditional DO INSTEAD rule, assume that the
1513 : : * view is auto-updatable. If it isn't, rewriteTargetView() will
1514 : : * throw an error.
1515 : : */
1516 [ + + ]: 51 : if (!found)
1517 : 45 : isAutoUpdatableView = true;
1518 : : }
1519 : :
7165 mail@joeconway.com 1520 : 153 : newValues = NIL;
2580 dean.a.rasheed@gmail 1521 : 153 : allReplaced = true;
7165 mail@joeconway.com 1522 [ + - + + : 468 : foreach(lc, rte->values_lists)
+ + ]
1523 : : {
7102 bruce@momjian.us 1524 : 315 : List *sublist = (List *) lfirst(lc);
1525 : 315 : List *newList = NIL;
1526 : : ListCell *lc2;
1527 : : int i;
1528 : :
2569 dean.a.rasheed@gmail 1529 [ - + ]: 315 : Assert(list_length(sublist) == numattrs);
1530 : :
1531 : 315 : i = 0;
1532 [ + - + + : 1251 : foreach(lc2, sublist)
+ + ]
1533 : : {
7102 bruce@momjian.us 1534 : 936 : Node *col = (Node *) lfirst(lc2);
2569 dean.a.rasheed@gmail 1535 : 936 : int attrno = attrnos[i++];
1536 : :
7165 mail@joeconway.com 1537 [ + + ]: 936 : if (IsA(col, SetToDefault))
1538 : : {
1539 : : Form_pg_attribute att_tup;
1540 : : Node *new_expr;
1541 : :
1542 : : /*
1543 : : * If this column isn't used, just replace the DEFAULT with
1544 : : * NULL (attrno will be 0 in this case because the targetlist
1545 : : * entry will have been replaced by the default expression).
1546 : : */
1939 tgl@sss.pgh.pa.us 1547 [ + + ]: 437 : if (bms_is_member(i, unused_cols))
1548 : 57 : {
1549 : 57 : SetToDefault *def = (SetToDefault *) col;
1550 : :
1551 : 57 : newList = lappend(newList,
1552 : 57 : makeNullConst(def->typeId,
1553 : : def->typeMod,
1554 : : def->collation));
1555 : 57 : continue;
1556 : : }
1557 : :
2569 dean.a.rasheed@gmail 1558 [ - + ]: 380 : if (attrno == 0)
2569 dean.a.rasheed@gmail 1559 [ # # ]:UBC 0 : elog(ERROR, "cannot set value in column %d to DEFAULT", i);
1251 tgl@sss.pgh.pa.us 1560 [ + - - + ]:CBC 380 : Assert(attrno > 0 && attrno <= target_relation->rd_att->natts);
3129 andres@anarazel.de 1561 : 380 : att_tup = TupleDescAttr(target_relation->rd_att, attrno - 1);
1562 : :
1251 tgl@sss.pgh.pa.us 1563 [ + - ]: 380 : if (!att_tup->attisdropped)
7165 mail@joeconway.com 1564 : 380 : new_expr = build_column_default(target_relation, attrno);
1565 : : else
7102 bruce@momjian.us 1566 :UBC 0 : new_expr = NULL; /* force a NULL if dropped */
1567 : :
1568 : : /*
1569 : : * If there is no default (ie, default is effectively NULL),
1570 : : * we've got to explicitly set the column to NULL, unless the
1571 : : * target relation is an auto-updatable view.
1572 : : */
7165 mail@joeconway.com 1573 [ + + ]:CBC 380 : if (!new_expr)
1574 : : {
2580 dean.a.rasheed@gmail 1575 [ + + ]: 179 : if (isAutoUpdatableView)
1576 : : {
1577 : : /* Leave the value untouched */
1578 : 75 : newList = lappend(newList, col);
1579 : 75 : allReplaced = false;
1580 : 75 : continue;
1581 : : }
1582 : :
410 tgl@sss.pgh.pa.us 1583 : 104 : new_expr = coerce_null_to_domain(att_tup->atttypid,
1584 : : att_tup->atttypmod,
1585 : : att_tup->attcollation,
1586 : 104 : att_tup->attlen,
1587 : 104 : att_tup->attbyval);
1588 : : }
7165 mail@joeconway.com 1589 : 305 : newList = lappend(newList, new_expr);
1590 : : }
1591 : : else
1592 : 499 : newList = lappend(newList, col);
1593 : : }
1594 : 315 : newValues = lappend(newValues, newList);
1595 : : }
1596 : 153 : rte->values_lists = newValues;
1597 : :
2569 dean.a.rasheed@gmail 1598 : 153 : pfree(attrnos);
1599 : :
2580 1600 : 153 : return allReplaced;
1601 : : }
1602 : :
1603 : : /*
1604 : : * Mop up any remaining DEFAULT items in the given VALUES RTE by
1605 : : * replacing them with NULL constants.
1606 : : *
1607 : : * This is used for the product queries generated by DO ALSO rules attached to
1608 : : * an auto-updatable view. The action can't depend on the "target relation"
1609 : : * since the product query might not have one (it needn't be an INSERT).
1610 : : * Essentially, such queries are treated as being attached to a rule-updatable
1611 : : * view.
1612 : : */
1613 : : static void
1251 tgl@sss.pgh.pa.us 1614 : 12 : rewriteValuesRTEToNulls(Query *parsetree, RangeTblEntry *rte)
1615 : : {
1616 : : List *newValues;
1617 : : ListCell *lc;
1618 : :
1619 : 12 : newValues = NIL;
1620 [ + - + + : 36 : foreach(lc, rte->values_lists)
+ + ]
1621 : : {
1622 : 24 : List *sublist = (List *) lfirst(lc);
1623 : 24 : List *newList = NIL;
1624 : : ListCell *lc2;
1625 : :
1626 [ + - + + : 102 : foreach(lc2, sublist)
+ + ]
1627 : : {
1628 : 78 : Node *col = (Node *) lfirst(lc2);
1629 : :
1630 [ + + ]: 78 : if (IsA(col, SetToDefault))
1631 : : {
1632 : 33 : SetToDefault *def = (SetToDefault *) col;
1633 : :
1634 : 33 : newList = lappend(newList, makeNullConst(def->typeId,
1635 : : def->typeMod,
1636 : : def->collation));
1637 : : }
1638 : : else
1639 : 45 : newList = lappend(newList, col);
1640 : : }
1641 : 24 : newValues = lappend(newValues, newList);
1642 : : }
1643 : 12 : rte->values_lists = newValues;
1644 : 12 : }
1645 : :
1646 : :
1647 : : /*
1648 : : * matchLocks -
1649 : : * match a relation's list of locks and returns the matching rules
1650 : : */
1651 : : static List *
9298 1652 : 45527 : matchLocks(CmdType event,
1653 : : Relation relation,
1654 : : int varno,
1655 : : Query *parsetree,
1656 : : bool *hasUpdate)
1657 : : {
745 dean.a.rasheed@gmail 1658 : 45527 : RuleLock *rulelocks = relation->rd_rules;
8548 tgl@sss.pgh.pa.us 1659 : 45527 : List *matching_locks = NIL;
1660 : : int nlocks;
1661 : : int i;
1662 : :
8419 1663 [ + + ]: 45527 : if (rulelocks == NULL)
1664 : 42625 : return NIL;
1665 : :
9298 1666 [ + - ]: 2902 : if (parsetree->commandType != CMD_SELECT)
1667 : : {
1668 [ - + ]: 2902 : if (parsetree->resultRelation != varno)
9298 tgl@sss.pgh.pa.us 1669 :UBC 0 : return NIL;
1670 : : }
1671 : :
9298 tgl@sss.pgh.pa.us 1672 :CBC 2902 : nlocks = rulelocks->numLocks;
1673 : :
1674 [ + + ]: 6614 : for (i = 0; i < nlocks; i++)
1675 : : {
1676 : 3721 : RewriteRule *oneLock = rulelocks->rules[i];
1677 : :
3964 andres@anarazel.de 1678 [ + + ]: 3721 : if (oneLock->event == CMD_UPDATE)
1679 : 330 : *hasUpdate = true;
1680 : :
1681 : : /*
1682 : : * Suppress ON INSERT/UPDATE/DELETE rules that are disabled or
1683 : : * configured to not fire during the current session's replication
1684 : : * role. ON SELECT rules will always be applied in order to keep views
1685 : : * working even in LOCAL or REPLICA role.
1686 : : */
6936 JanWieck@Yahoo.com 1687 [ + + ]: 3721 : if (oneLock->event != CMD_SELECT)
1688 : : {
1689 [ + + ]: 1377 : if (SessionReplicationRole == SESSION_REPLICATION_ROLE_REPLICA)
1690 : : {
1691 [ + + ]: 6 : if (oneLock->enabled == RULE_FIRES_ON_ORIGIN ||
1692 [ - + ]: 3 : oneLock->enabled == RULE_DISABLED)
1693 : 3 : continue;
1694 : : }
1695 : : else /* ORIGIN or LOCAL ROLE */
1696 : : {
1697 [ + + ]: 1371 : if (oneLock->enabled == RULE_FIRES_ON_REPLICA ||
1698 [ + + ]: 1368 : oneLock->enabled == RULE_DISABLED)
1699 : 15 : continue;
1700 : : }
1701 : :
1702 : : /* Non-SELECT rules are not supported for MERGE */
745 dean.a.rasheed@gmail 1703 [ + + ]: 1359 : if (parsetree->commandType == CMD_MERGE)
1704 [ + - ]: 9 : ereport(ERROR,
1705 : : errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1706 : : errmsg("cannot execute MERGE on relation \"%s\"",
1707 : : RelationGetRelationName(relation)),
1708 : : errdetail("MERGE is not supported for relations with rules."));
1709 : : }
1710 : :
9298 tgl@sss.pgh.pa.us 1711 [ + + ]: 3694 : if (oneLock->event == event)
1712 : : {
1713 [ - + - - ]: 804 : if (parsetree->commandType != CMD_SELECT ||
4574 kgrittn@postgresql.o 1714 :UBC 0 : rangeTableEntry_used((Node *) parsetree, varno, 0))
8548 tgl@sss.pgh.pa.us 1715 :CBC 804 : matching_locks = lappend(matching_locks, oneLock);
1716 : : }
1717 : : }
1718 : :
1719 : 2893 : return matching_locks;
1720 : : }
1721 : :
1722 : :
1723 : : /*
1724 : : * ApplyRetrieveRule - expand an ON SELECT rule
1725 : : */
1726 : : static Query *
9298 1727 : 9198 : ApplyRetrieveRule(Query *parsetree,
1728 : : RewriteRule *rule,
1729 : : int rt_index,
1730 : : Relation relation,
1731 : : List *activeRIRs)
1732 : : {
1733 : : Query *rule_action;
1734 : : RangeTblEntry *rte;
1735 : : RowMarkClause *rc;
1736 : : int numCols;
1737 : :
7959 neilc@samurai.com 1738 [ - + ]: 9198 : if (list_length(rule->actions) != 1)
8269 tgl@sss.pgh.pa.us 1739 [ # # ]:UBC 0 : elog(ERROR, "expected just one rule action");
9298 tgl@sss.pgh.pa.us 1740 [ - + ]:CBC 9198 : if (rule->qual != NULL)
8269 tgl@sss.pgh.pa.us 1741 [ # # ]:UBC 0 : elog(ERROR, "cannot handle qualified ON SELECT rule");
1742 : :
1743 : : /* Check if the expansion of non-system views are restricted */
587 msawada@postgresql.o 1744 [ + + + + :CBC 9198 : if (unlikely((restrict_nonsystem_relation_kind & RESTRICT_RELKIND_VIEW) != 0 &&
+ + ]
1745 : : RelationGetRelid(relation) >= FirstNormalObjectId))
1746 [ + - ]: 3 : ereport(ERROR,
1747 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
1748 : : errmsg("access to non-system view \"%s\" is restricted",
1749 : : RelationGetRelationName(relation))));
1750 : :
5635 tgl@sss.pgh.pa.us 1751 [ + + ]: 9195 : if (rt_index == parsetree->resultRelation)
1752 : : {
1753 : : /*
1754 : : * We have a view as the result relation of the query, and it wasn't
1755 : : * rewritten by any rule. This case is supported if there is an
1756 : : * INSTEAD OF trigger that will trap attempts to insert/update/delete
1757 : : * view rows. The executor will check that; for the moment just plow
1758 : : * ahead. We have two cases:
1759 : : *
1760 : : * For INSERT, we needn't do anything. The unmodified RTE will serve
1761 : : * fine as the result relation.
1762 : : *
1763 : : * For UPDATE/DELETE/MERGE, we need to expand the view so as to have
1764 : : * source data for the operation. But we also need an unmodified RTE
1765 : : * to serve as the target. So, copy the RTE and add the copy to the
1766 : : * rangetable. Note that the copy does not get added to the jointree.
1767 : : * Also note that there's a hack in fireRIRrules to avoid calling this
1768 : : * function again when it arrives at the copied RTE.
1769 : : */
1770 [ + + ]: 204 : if (parsetree->commandType == CMD_INSERT)
1771 : 60 : return parsetree;
1772 [ + + ]: 144 : else if (parsetree->commandType == CMD_UPDATE ||
745 dean.a.rasheed@gmail 1773 [ + + ]: 66 : parsetree->commandType == CMD_DELETE ||
1774 [ + - ]: 39 : parsetree->commandType == CMD_MERGE)
5635 tgl@sss.pgh.pa.us 1775 : 144 : {
1776 : : RangeTblEntry *newrte;
1777 : : Var *var;
1778 : : TargetEntry *tle;
1779 : :
1780 : 144 : rte = rt_fetch(rt_index, parsetree->rtable);
1781 : 144 : newrte = copyObject(rte);
1782 : 144 : parsetree->rtable = lappend(parsetree->rtable, newrte);
1783 : 144 : parsetree->resultRelation = list_length(parsetree->rtable);
1784 : : /* parsetree->mergeTargetRelation unchanged (use expanded view) */
1785 : :
1786 : : /*
1787 : : * For the most part, Vars referencing the view should remain as
1788 : : * they are, meaning that they implicitly represent OLD values.
1789 : : * But in the RETURNING list if any, we want such Vars to
1790 : : * represent NEW values, so change them to reference the new RTE.
1791 : : *
1792 : : * Since ChangeVarNodes scribbles on the tree in-place, copy the
1793 : : * RETURNING list first for safety.
1794 : : */
1795 : 144 : parsetree->returningList = copyObject(parsetree->returningList);
1796 : 144 : ChangeVarNodes((Node *) parsetree->returningList, rt_index,
1797 : : parsetree->resultRelation, 0);
1798 : :
1799 : : /*
1800 : : * To allow the executor to compute the original view row to pass
1801 : : * to the INSTEAD OF trigger, we add a resjunk whole-row Var
1802 : : * referencing the original RTE. This will later get expanded
1803 : : * into a RowExpr computing all the OLD values of the view row.
1804 : : */
3030 1805 : 144 : var = makeWholeRowVar(rte, rt_index, 0, false);
1806 : 144 : tle = makeTargetEntry((Expr *) var,
1807 : 144 : list_length(parsetree->targetList) + 1,
1808 : : pstrdup("wholerow"),
1809 : : true);
1810 : :
1811 : 144 : parsetree->targetList = lappend(parsetree->targetList, tle);
1812 : :
1813 : : /* Now, continue with expanding the original view RTE */
1814 : : }
1815 : : else
5635 tgl@sss.pgh.pa.us 1816 [ # # ]:UBC 0 : elog(ERROR, "unrecognized commandType: %d",
1817 : : (int) parsetree->commandType);
1818 : : }
1819 : :
1820 : : /*
1821 : : * Check if there's a FOR [KEY] UPDATE/SHARE clause applying to this view.
1822 : : *
1823 : : * Note: we needn't explicitly consider any such clauses appearing in
1824 : : * ancestor query levels; their effects have already been pushed down to
1825 : : * here by markQueryForLocking, and will be reflected in "rc".
1826 : : */
5982 tgl@sss.pgh.pa.us 1827 :CBC 9135 : rc = get_parse_rowmark(parsetree, rt_index);
1828 : :
1829 : : /*
1830 : : * Make a modifiable copy of the view query, and acquire needed locks on
1831 : : * the relations it mentions. Force at least RowShareLock for all such
1832 : : * rels if there's a FOR [KEY] UPDATE/SHARE clause affecting this view.
1833 : : */
7963 neilc@samurai.com 1834 : 9135 : rule_action = copyObject(linitial(rule->actions));
1835 : :
2892 tgl@sss.pgh.pa.us 1836 : 9135 : AcquireRewriteLocks(rule_action, true, (rc != NULL));
1837 : :
1838 : : /*
1839 : : * If FOR [KEY] UPDATE/SHARE of view, mark all the contained tables as
1840 : : * implicit FOR [KEY] UPDATE/SHARE, the same as the parser would have done
1841 : : * if the view's subquery had been written out explicitly.
1842 : : */
1843 [ + + ]: 9135 : if (rc != NULL)
1844 : 48 : markQueryForLocking(rule_action, (Node *) rule_action->jointree,
1845 : : rc->strength, rc->waitPolicy, true);
1846 : :
1847 : : /*
1848 : : * Recursively expand any view references inside the view.
1849 : : */
1850 : 9135 : rule_action = fireRIRrules(rule_action, activeRIRs);
1851 : :
1852 : : /*
1853 : : * Make sure the query is marked as having row security if the view query
1854 : : * does.
1855 : : */
489 nathan@postgresql.or 1856 : 9120 : parsetree->hasRowSecurity |= rule_action->hasRowSecurity;
1857 : :
1858 : : /*
1859 : : * Now, plug the view query in as a subselect, converting the relation's
1860 : : * original RTE to a subquery RTE.
1861 : : */
9298 tgl@sss.pgh.pa.us 1862 : 9120 : rte = rt_fetch(rt_index, parsetree->rtable);
1863 : :
8769 1864 : 9120 : rte->rtekind = RTE_SUBQUERY;
9298 1865 : 9120 : rte->subquery = rule_action;
2735 1866 [ - + + + ]: 9120 : rte->security_barrier = RelationIsSecurityView(relation);
1867 : :
1868 : : /*
1869 : : * Clear fields that should not be set in a subquery RTE. Note that we
1870 : : * leave the relid, relkind, rellockmode, and perminfoindex fields set, so
1871 : : * that the view relation can be appropriately locked before execution and
1872 : : * its permissions checked.
1873 : : */
1152 1874 : 9120 : rte->tablesample = NULL;
1875 : 9120 : rte->inh = false; /* must not be set for a subquery */
1876 : :
1877 : : /*
1878 : : * Since we allow CREATE OR REPLACE VIEW to add columns to a view, the
1879 : : * rule_action might emit more columns than we expected when the current
1880 : : * query was parsed. Various places expect rte->eref->colnames to be
1881 : : * consistent with the non-junk output columns of the subquery, so patch
1882 : : * things up if necessary by adding some dummy column names.
1883 : : */
1104 1884 : 9120 : numCols = ExecCleanTargetListLength(rule_action->targetList);
1885 [ + + ]: 9129 : while (list_length(rte->eref->colnames) < numCols)
1886 : : {
1887 : 9 : rte->eref->colnames = lappend(rte->eref->colnames,
1888 : 9 : makeString(pstrdup("?column?")));
1889 : : }
1890 : :
9662 1891 : 9120 : return parsetree;
1892 : : }
1893 : :
1894 : : /*
1895 : : * Recursively mark all relations used by a view as FOR [KEY] UPDATE/SHARE.
1896 : : *
1897 : : * This may generate an invalid query, eg if some sub-query uses an
1898 : : * aggregate. We leave it to the planner to detect that.
1899 : : *
1900 : : * NB: this must agree with the parser's transformLockingClause() routine.
1901 : : * However, we used to have to avoid marking a view's OLD and NEW rels for
1902 : : * updating, which motivated scanning the jointree to determine which rels
1903 : : * are used. Possibly that could now be simplified into just scanning the
1904 : : * rangetable as the parser does.
1905 : : */
1906 : : static void
5982 1907 : 96 : markQueryForLocking(Query *qry, Node *jtnode,
1908 : : LockClauseStrength strength, LockWaitPolicy waitPolicy,
1909 : : bool pushedDown)
1910 : : {
6954 1911 [ - + ]: 96 : if (jtnode == NULL)
6954 tgl@sss.pgh.pa.us 1912 :UBC 0 : return;
6954 tgl@sss.pgh.pa.us 1913 [ + + ]:CBC 96 : if (IsA(jtnode, RangeTblRef))
1914 : : {
1915 : 48 : int rti = ((RangeTblRef *) jtnode)->rtindex;
1916 : 48 : RangeTblEntry *rte = rt_fetch(rti, qry->rtable);
1917 : :
8769 1918 [ + - ]: 48 : if (rte->rtekind == RTE_RELATION)
1919 : : {
1920 : : RTEPermissionInfo *perminfo;
1921 : :
4177 alvherre@alvh.no-ip. 1922 : 48 : applyLockingClause(qry, rti, strength, waitPolicy, pushedDown);
1923 : :
1195 1924 : 48 : perminfo = getRTEPermissionInfo(qry->rteperminfos, rte);
1925 : 48 : perminfo->requiredPerms |= ACL_SELECT_FOR_UPDATE;
1926 : : }
8769 tgl@sss.pgh.pa.us 1927 [ # # ]:UBC 0 : else if (rte->rtekind == RTE_SUBQUERY)
1928 : : {
4177 alvherre@alvh.no-ip. 1929 : 0 : applyLockingClause(qry, rti, strength, waitPolicy, pushedDown);
1930 : : /* FOR UPDATE/SHARE of subquery is propagated to subquery's rels */
6954 tgl@sss.pgh.pa.us 1931 : 0 : markQueryForLocking(rte->subquery, (Node *) rte->subquery->jointree,
1932 : : strength, waitPolicy, true);
1933 : : }
1934 : : /* other RTE types are unaffected by FOR UPDATE */
1935 : : }
6954 tgl@sss.pgh.pa.us 1936 [ + - ]:CBC 48 : else if (IsA(jtnode, FromExpr))
1937 : : {
1938 : 48 : FromExpr *f = (FromExpr *) jtnode;
1939 : : ListCell *l;
1940 : :
1941 [ + - + + : 96 : foreach(l, f->fromlist)
+ + ]
4177 alvherre@alvh.no-ip. 1942 : 48 : markQueryForLocking(qry, lfirst(l), strength, waitPolicy, pushedDown);
1943 : : }
6954 tgl@sss.pgh.pa.us 1944 [ # # ]:UBC 0 : else if (IsA(jtnode, JoinExpr))
1945 : : {
1946 : 0 : JoinExpr *j = (JoinExpr *) jtnode;
1947 : :
4177 alvherre@alvh.no-ip. 1948 : 0 : markQueryForLocking(qry, j->larg, strength, waitPolicy, pushedDown);
1949 : 0 : markQueryForLocking(qry, j->rarg, strength, waitPolicy, pushedDown);
1950 : : }
1951 : : else
6954 tgl@sss.pgh.pa.us 1952 [ # # ]: 0 : elog(ERROR, "unrecognized node type: %d",
1953 : : (int) nodeTag(jtnode));
1954 : : }
1955 : :
1956 : :
1957 : : /*
1958 : : * fireRIRonSubLink -
1959 : : * Apply fireRIRrules() to each SubLink (subselect in expression) found
1960 : : * in the given tree.
1961 : : *
1962 : : * NOTE: although this has the form of a walker, we cheat and modify the
1963 : : * SubLink nodes in-place. It is caller's responsibility to ensure that
1964 : : * no unwanted side-effects occur!
1965 : : *
1966 : : * This is unlike most of the other routines that recurse into subselects,
1967 : : * because we must take control at the SubLink node in order to replace
1968 : : * the SubLink's subselect link with the possibly-rewritten subquery.
1969 : : */
1970 : : static bool
489 nathan@postgresql.or 1971 :CBC 1645071 : fireRIRonSubLink(Node *node, fireRIRonSubLink_context *context)
1972 : : {
10026 bruce@momjian.us 1973 [ + + ]: 1645071 : if (node == NULL)
9662 tgl@sss.pgh.pa.us 1974 : 323933 : return false;
1975 [ + + ]: 1321138 : if (IsA(node, SubLink))
1976 : : {
1977 : 28059 : SubLink *sub = (SubLink *) node;
1978 : :
1979 : : /* Do what we came for */
8419 1980 : 28059 : sub->subselect = (Node *) fireRIRrules((Query *) sub->subselect,
1981 : : context->activeRIRs);
1982 : :
1983 : : /*
1984 : : * Remember if any of the sublinks have row security.
1985 : : */
489 nathan@postgresql.or 1986 : 28023 : context->hasRowSecurity |= ((Query *) sub->subselect)->hasRowSecurity;
1987 : :
1988 : : /* Fall through to process lefthand args of SubLink */
1989 : : }
1990 : :
1991 : : /*
1992 : : * Do NOT recurse into Query nodes, because fireRIRrules already processed
1993 : : * subselects of subselects for us.
1994 : : */
472 peter@eisentraut.org 1995 : 1321102 : return expression_tree_walker(node, fireRIRonSubLink, context);
1996 : : }
1997 : :
1998 : :
1999 : : /*
2000 : : * fireRIRrules -
2001 : : * Apply all RIR rules on each rangetable entry in the given query
2002 : : *
2003 : : * activeRIRs is a list of the OIDs of views we're already processing RIR
2004 : : * rules for, used to detect/reject recursion.
2005 : : */
2006 : : static Query *
2892 tgl@sss.pgh.pa.us 2007 : 307821 : fireRIRrules(Query *parsetree, List *activeRIRs)
2008 : : {
5635 2009 : 307821 : int origResultRelation = parsetree->resultRelation;
2010 : : int rt_index;
2011 : : ListCell *lc;
2012 : :
2013 : : /*
2014 : : * Expand SEARCH and CYCLE clauses in CTEs.
2015 : : *
2016 : : * This is just a convenient place to do this, since we are already
2017 : : * looking at each Query.
2018 : : */
1868 peter@eisentraut.org 2019 [ + + + + : 310087 : foreach(lc, parsetree->cteList)
+ + ]
2020 : : {
2021 : 2269 : CommonTableExpr *cte = lfirst_node(CommonTableExpr, lc);
2022 : :
2023 [ + + + + ]: 2269 : if (cte->search_clause || cte->cycle_clause)
2024 : : {
2025 : 72 : cte = rewriteSearchAndCycle(cte);
2026 : 69 : lfirst(lc) = cte;
2027 : : }
2028 : : }
2029 : :
2030 : : /*
2031 : : * don't try to convert this into a foreach loop, because rtable list can
2032 : : * get changed each time through...
2033 : : */
10026 bruce@momjian.us 2034 : 307818 : rt_index = 0;
7959 neilc@samurai.com 2035 [ + + ]: 698647 : while (rt_index < list_length(parsetree->rtable))
2036 : : {
2037 : : RangeTblEntry *rte;
2038 : : Relation rel;
2039 : : List *locks;
2040 : : RuleLock *rules;
2041 : : RewriteRule *rule;
2042 : : int i;
2043 : :
10026 bruce@momjian.us 2044 : 390847 : ++rt_index;
2045 : :
9631 tgl@sss.pgh.pa.us 2046 : 390847 : rte = rt_fetch(rt_index, parsetree->rtable);
2047 : :
2048 : : /*
2049 : : * A subquery RTE can't have associated rules, so there's nothing to
2050 : : * do to this level of the query, but we must recurse into the
2051 : : * subquery to expand any rule references in it.
2052 : : */
8769 2053 [ + + ]: 390847 : if (rte->rtekind == RTE_SUBQUERY)
2054 : : {
2892 2055 : 31294 : rte->subquery = fireRIRrules(rte->subquery, activeRIRs);
2056 : :
2057 : : /*
2058 : : * While we are here, make sure the query is marked as having row
2059 : : * security if any of its subqueries do.
2060 : : */
489 nathan@postgresql.or 2061 : 31294 : parsetree->hasRowSecurity |= rte->subquery->hasRowSecurity;
2062 : :
9298 tgl@sss.pgh.pa.us 2063 : 31294 : continue;
2064 : : }
2065 : :
2066 : : /*
2067 : : * Joins and other non-relation RTEs can be ignored completely.
2068 : : */
8769 2069 [ + + ]: 359553 : if (rte->rtekind != RTE_RELATION)
2070 : 93819 : continue;
2071 : :
2072 : : /*
2073 : : * Always ignore RIR rules for materialized views referenced in
2074 : : * queries. (This does not prevent refreshing MVs, since they aren't
2075 : : * referenced in their own query definitions.)
2076 : : *
2077 : : * Note: in the future we might want to allow MVs to be conditionally
2078 : : * expanded as if they were regular views, if they are not scannable.
2079 : : * In that case this test would need to be postponed till after we've
2080 : : * opened the rel, so that we could check its state.
2081 : : */
4705 2082 [ + + ]: 265734 : if (rte->relkind == RELKIND_MATVIEW)
2083 : 229 : continue;
2084 : :
2085 : : /*
2086 : : * In INSERT ... ON CONFLICT, ignore the EXCLUDED pseudo-relation;
2087 : : * even if it points to a view, we needn't expand it, and should not
2088 : : * because we want the RTE to remain of RTE_RELATION type. Otherwise,
2089 : : * it would get changed to RTE_SUBQUERY type, which is an
2090 : : * untested/unsupported situation.
2091 : : */
2780 2092 [ + + ]: 265505 : if (parsetree->onConflict &&
2093 [ + + ]: 2374 : rt_index == parsetree->onConflict->exclRelIndex)
2094 : 871 : continue;
2095 : :
2096 : : /*
2097 : : * If the table is not referenced in the query, then we ignore it.
2098 : : * This prevents infinite expansion loop due to new rtable entries
2099 : : * inserted by expansion of a rule. A table is referenced if it is
2100 : : * part of the join set (a source table), or is referenced by any Var
2101 : : * nodes, or is the result table.
2102 : : */
7595 2103 [ + + ]: 264634 : if (rt_index != parsetree->resultRelation &&
2104 [ + + ]: 221268 : !rangeTableEntry_used((Node *) parsetree, rt_index, 0))
10026 bruce@momjian.us 2105 : 3733 : continue;
2106 : :
2107 : : /*
2108 : : * Also, if this is a new result relation introduced by
2109 : : * ApplyRetrieveRule, we don't want to do anything more with it.
2110 : : */
5635 tgl@sss.pgh.pa.us 2111 [ + + + + ]: 260901 : if (rt_index == parsetree->resultRelation &&
2112 : : rt_index != origResultRelation)
2113 : 144 : continue;
2114 : :
2115 : : /*
2116 : : * We can use NoLock here since either the parser or
2117 : : * AcquireRewriteLocks should have locked the rel already.
2118 : : */
4 peter@eisentraut.org 2119 :GNC 260757 : rel = relation_open(rte->relid, NoLock);
2120 : :
2121 : : /*
2122 : : * Collect the RIR rules that we must apply
2123 : : */
9656 tgl@sss.pgh.pa.us 2124 :CBC 260757 : rules = rel->rd_rules;
4195 sfrost@snowman.net 2125 [ + + ]: 260757 : if (rules != NULL)
2126 : : {
2127 : 9852 : locks = NIL;
2128 [ + + ]: 21360 : for (i = 0; i < rules->numLocks; i++)
2129 : : {
2130 : 11508 : rule = rules->rules[i];
2131 [ + + ]: 11508 : if (rule->event != CMD_SELECT)
2132 : 2310 : continue;
2133 : :
2134 : 9198 : locks = lappend(locks, rule);
2135 : : }
2136 : :
2137 : : /*
2138 : : * If we found any, apply them --- but first check for recursion!
2139 : : */
2140 [ + + ]: 9852 : if (locks != NIL)
2141 : : {
2142 : : ListCell *l;
2143 : :
2144 [ - + ]: 9198 : if (list_member_oid(activeRIRs, RelationGetRelid(rel)))
4195 sfrost@snowman.net 2145 [ # # ]:UBC 0 : ereport(ERROR,
2146 : : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2147 : : errmsg("infinite recursion detected in rules for relation \"%s\"",
2148 : : RelationGetRelationName(rel))));
2433 tgl@sss.pgh.pa.us 2149 :CBC 9198 : activeRIRs = lappend_oid(activeRIRs, RelationGetRelid(rel));
2150 : :
4195 sfrost@snowman.net 2151 [ + - + + : 18378 : foreach(l, locks)
+ + ]
2152 : : {
2153 : 9198 : rule = lfirst(l);
2154 : :
2155 : 9198 : parsetree = ApplyRetrieveRule(parsetree,
2156 : : rule,
2157 : : rt_index,
2158 : : rel,
2159 : : activeRIRs);
2160 : : }
2161 : :
2433 tgl@sss.pgh.pa.us 2162 : 9180 : activeRIRs = list_delete_last(activeRIRs);
2163 : : }
2164 : : }
2165 : :
2610 andres@anarazel.de 2166 : 260739 : table_close(rel, NoLock);
2167 : : }
2168 : :
2169 : : /* Recurse into subqueries in WITH */
6371 tgl@sss.pgh.pa.us 2170 [ + + + + : 310066 : foreach(lc, parsetree->cteList)
+ + ]
2171 : : {
2172 : 2266 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
2173 : :
2174 : 2266 : cte->ctequery = (Node *)
2892 2175 : 2266 : fireRIRrules((Query *) cte->ctequery, activeRIRs);
2176 : :
2177 : : /*
2178 : : * While we are here, make sure the query is marked as having row
2179 : : * security if any of its CTEs do.
2180 : : */
489 nathan@postgresql.or 2181 : 2266 : parsetree->hasRowSecurity |= ((Query *) cte->ctequery)->hasRowSecurity;
2182 : : }
2183 : :
2184 : : /*
2185 : : * Recurse into sublink subqueries, too. But we already did the ones in
2186 : : * the rtable and cteList.
2187 : : */
9298 tgl@sss.pgh.pa.us 2188 [ + + ]: 307800 : if (parsetree->hasSubLinks)
2189 : : {
2190 : : fireRIRonSubLink_context context;
2191 : :
489 nathan@postgresql.or 2192 : 22522 : context.activeRIRs = activeRIRs;
2193 : 22522 : context.hasRowSecurity = false;
2194 : :
472 peter@eisentraut.org 2195 : 22522 : query_tree_walker(parsetree, fireRIRonSubLink, &context,
2196 : : QTW_IGNORE_RC_SUBQUERIES);
2197 : :
2198 : : /*
2199 : : * Make sure the query is marked as having row security if any of its
2200 : : * sublinks do.
2201 : : */
489 nathan@postgresql.or 2202 : 22522 : parsetree->hasRowSecurity |= context.hasRowSecurity;
2203 : : }
2204 : :
2205 : : /*
2206 : : * Apply any row-level security policies. We do this last because it
2207 : : * requires special recursion detection if the new quals have sublink
2208 : : * subqueries, and if we did it in the loop above query_tree_walker would
2209 : : * then recurse into those quals a second time.
2210 : : */
3980 sfrost@snowman.net 2211 : 307800 : rt_index = 0;
2212 [ + + + + : 698542 : foreach(lc, parsetree->rtable)
+ + ]
2213 : : {
2214 : 390829 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
2215 : : Relation rel;
2216 : : List *securityQuals;
2217 : : List *withCheckOptions;
2218 : : bool hasRowSecurity;
2219 : : bool hasSubLinks;
2220 : :
2221 : 390829 : ++rt_index;
2222 : :
2223 : : /* Only normal relations can have RLS policies */
383 rguo@postgresql.org 2224 [ + + ]: 390829 : if (rte->rtekind != RTE_RELATION ||
2225 [ + + ]: 256596 : (rte->relkind != RELKIND_RELATION &&
2226 [ + + ]: 13184 : rte->relkind != RELKIND_PARTITIONED_TABLE))
3980 sfrost@snowman.net 2227 : 138926 : continue;
2228 : :
4 peter@eisentraut.org 2229 :GNC 251903 : rel = relation_open(rte->relid, NoLock);
2230 : :
2231 : : /*
2232 : : * Fetch any new security quals that must be applied to this RTE.
2233 : : */
3834 sfrost@snowman.net 2234 :CBC 251903 : get_row_security_policies(parsetree, rte, rt_index,
2235 : : &securityQuals, &withCheckOptions,
2236 : : &hasRowSecurity, &hasSubLinks);
2237 : :
3980 2238 [ + + + + ]: 251873 : if (securityQuals != NIL || withCheckOptions != NIL)
2239 : : {
2240 [ + + ]: 1621 : if (hasSubLinks)
2241 : : {
2242 : : acquireLocksOnSubLinks_context context;
2243 : : fireRIRonSubLink_context fire_context;
2244 : :
2245 : : /*
2246 : : * Recursively process the new quals, checking for infinite
2247 : : * recursion.
2248 : : */
2249 [ + + ]: 366 : if (list_member_oid(activeRIRs, RelationGetRelid(rel)))
2250 [ + - ]: 21 : ereport(ERROR,
2251 : : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2252 : : errmsg("infinite recursion detected in policy for relation \"%s\"",
2253 : : RelationGetRelationName(rel))));
2254 : :
2433 tgl@sss.pgh.pa.us 2255 : 345 : activeRIRs = lappend_oid(activeRIRs, RelationGetRelid(rel));
2256 : :
2257 : : /*
2258 : : * get_row_security_policies just passed back securityQuals
2259 : : * and/or withCheckOptions, and there were SubLinks, make sure
2260 : : * we lock any relations which are referenced.
2261 : : *
2262 : : * These locks would normally be acquired by the parser, but
2263 : : * securityQuals and withCheckOptions are added post-parsing.
2264 : : */
3852 sfrost@snowman.net 2265 : 345 : context.for_execute = true;
2266 : 345 : (void) acquireLocksOnSubLinks((Node *) securityQuals, &context);
2267 : 345 : (void) acquireLocksOnSubLinks((Node *) withCheckOptions,
2268 : : &context);
2269 : :
2270 : : /*
2271 : : * Now that we have the locks on anything added by
2272 : : * get_row_security_policies, fire any RIR rules for them.
2273 : : */
489 nathan@postgresql.or 2274 : 345 : fire_context.activeRIRs = activeRIRs;
2275 : 345 : fire_context.hasRowSecurity = false;
2276 : :
3949 bruce@momjian.us 2277 : 345 : expression_tree_walker((Node *) securityQuals,
2278 : : fireRIRonSubLink, &fire_context);
2279 : :
2280 : 312 : expression_tree_walker((Node *) withCheckOptions,
2281 : : fireRIRonSubLink, &fire_context);
2282 : :
2283 : : /*
2284 : : * We can ignore the value of fire_context.hasRowSecurity
2285 : : * since we only reach this code in cases where hasRowSecurity
2286 : : * is already true.
2287 : : */
489 nathan@postgresql.or 2288 [ - + ]: 309 : Assert(hasRowSecurity);
2289 : :
2433 tgl@sss.pgh.pa.us 2290 : 309 : activeRIRs = list_delete_last(activeRIRs);
2291 : : }
2292 : :
2293 : : /*
2294 : : * Add the new security barrier quals to the start of the RTE's
2295 : : * list so that they get applied before any existing barrier quals
2296 : : * (which would have come from a security-barrier view, and should
2297 : : * get lower priority than RLS conditions on the table itself).
2298 : : */
3980 sfrost@snowman.net 2299 : 3128 : rte->securityQuals = list_concat(securityQuals,
2300 : 1564 : rte->securityQuals);
2301 : :
2302 : 1564 : parsetree->withCheckOptions = list_concat(withCheckOptions,
3189 tgl@sss.pgh.pa.us 2303 : 1564 : parsetree->withCheckOptions);
2304 : : }
2305 : :
2306 : : /*
2307 : : * Make sure the query is marked correctly if row-level security
2308 : : * applies, or if the new quals had sublinks.
2309 : : */
3980 sfrost@snowman.net 2310 [ + + ]: 251816 : if (hasRowSecurity)
2311 : 1870 : parsetree->hasRowSecurity = true;
2312 [ + + ]: 251816 : if (hasSubLinks)
2313 : 309 : parsetree->hasSubLinks = true;
2314 : :
2610 andres@anarazel.de 2315 : 251816 : table_close(rel, NoLock);
2316 : : }
2317 : :
10026 bruce@momjian.us 2318 : 307713 : return parsetree;
2319 : : }
2320 : :
2321 : :
2322 : : /*
2323 : : * Modify the given query by adding 'AND rule_qual IS NOT TRUE' to its
2324 : : * qualification. This is used to generate suitable "else clauses" for
2325 : : * conditional INSTEAD rules. (Unfortunately we must use "x IS NOT TRUE",
2326 : : * not just "NOT x" which the planner is much smarter about, else we will
2327 : : * do the wrong thing when the qual evaluates to NULL.)
2328 : : *
2329 : : * The rule_qual may contain references to OLD or NEW. OLD references are
2330 : : * replaced by references to the specified rt_index (the relation that the
2331 : : * rule applies to). NEW references are only possible for INSERT and UPDATE
2332 : : * queries on the relation itself, and so they should be replaced by copies
2333 : : * of the related entries in the query's own targetlist.
2334 : : */
2335 : : static Query *
8547 tgl@sss.pgh.pa.us 2336 : 222 : CopyAndAddInvertedQual(Query *parsetree,
2337 : : Node *rule_qual,
2338 : : int rt_index,
2339 : : CmdType event)
2340 : : {
2341 : : /* Don't scribble on the passed qual (it's in the relcache!) */
3293 peter_e@gmx.net 2342 : 222 : Node *new_qual = copyObject(rule_qual);
2343 : : acquireLocksOnSubLinks_context context;
2344 : :
4392 tgl@sss.pgh.pa.us 2345 : 222 : context.for_execute = true;
2346 : :
2347 : : /*
2348 : : * In case there are subqueries in the qual, acquire necessary locks and
2349 : : * fix any deleted JOIN RTE entries. (This is somewhat redundant with
2350 : : * rewriteRuleAction, but not entirely ... consider restructuring so that
2351 : : * we only need to process the qual this way once.)
2352 : : */
2353 : 222 : (void) acquireLocksOnSubLinks(new_qual, &context);
2354 : :
2355 : : /* Fix references to OLD */
9231 2356 : 222 : ChangeVarNodes(new_qual, PRS2_OLD_VARNO, rt_index, 0);
2357 : : /* Fix references to NEW */
2358 [ + + + + ]: 222 : if (event == CMD_INSERT || event == CMD_UPDATE)
4875 2359 [ + + ]: 432 : new_qual = ReplaceVarsFromTargetList(new_qual,
2360 : : PRS2_NEW_VARNO,
2361 : : 0,
2362 : 216 : rt_fetch(rt_index,
2363 : : parsetree->rtable),
2364 : : parsetree->targetList,
2365 : : parsetree->resultRelation,
2366 : : (event == CMD_UPDATE) ?
2367 : : REPLACEVARS_CHANGE_VARNO :
2368 : : REPLACEVARS_SUBSTITUTE_NULL,
2369 : : rt_index,
2370 : : &parsetree->hasSubLinks);
2371 : : /* And attach the fixed qual */
7590 2372 : 222 : AddInvertedQual(parsetree, new_qual);
2373 : :
2374 : 222 : return parsetree;
2375 : : }
2376 : :
2377 : :
2378 : : /*
2379 : : * fireRules -
2380 : : * Iterate through rule locks applying rules.
2381 : : *
2382 : : * Input arguments:
2383 : : * parsetree - original query
2384 : : * rt_index - RT index of result relation in original query
2385 : : * event - type of rule event
2386 : : * locks - list of rules to fire
2387 : : * Output arguments:
2388 : : * *instead_flag - set true if any unqualified INSTEAD rule is found
2389 : : * (must be initialized to false)
2390 : : * *returning_flag - set true if we rewrite RETURNING clause in any rule
2391 : : * (must be initialized to false)
2392 : : * *qual_product - filled with modified original query if any qualified
2393 : : * INSTEAD rule is found (must be initialized to NULL)
2394 : : * Return value:
2395 : : * list of rule actions adjusted for use with this query
2396 : : *
2397 : : * Qualified INSTEAD rules generate their action with the qualification
2398 : : * condition added. They also generate a modified version of the original
2399 : : * query with the negated qualification added, so that it will run only for
2400 : : * rows that the qualified action doesn't act on. (If there are multiple
2401 : : * qualified INSTEAD rules, we AND all the negated quals onto a single
2402 : : * modified original query.) We won't execute the original, unmodified
2403 : : * query if we find either qualified or unqualified INSTEAD rules. If
2404 : : * we find both, the modified original query is discarded too.
2405 : : */
2406 : : static List *
10415 bruce@momjian.us 2407 : 45467 : fireRules(Query *parsetree,
2408 : : int rt_index,
2409 : : CmdType event,
2410 : : List *locks,
2411 : : bool *instead_flag,
2412 : : bool *returning_flag,
2413 : : Query **qual_product)
2414 : : {
2415 : 45467 : List *results = NIL;
2416 : : ListCell *l;
2417 : :
7963 neilc@samurai.com 2418 [ + + + + : 46247 : foreach(l, locks)
+ + ]
2419 : : {
2420 : 786 : RewriteRule *rule_lock = (RewriteRule *) lfirst(l);
8548 tgl@sss.pgh.pa.us 2421 : 786 : Node *event_qual = rule_lock->qual;
2422 : 786 : List *actions = rule_lock->actions;
2423 : : QuerySource qsrc;
2424 : : ListCell *r;
2425 : :
2426 : : /* Determine correct QuerySource value for actions */
8553 2427 [ + + ]: 786 : if (rule_lock->isInstead)
2428 : : {
2429 [ + + ]: 594 : if (event_qual != NULL)
2430 : 225 : qsrc = QSRC_QUAL_INSTEAD_RULE;
2431 : : else
2432 : : {
2433 : 369 : qsrc = QSRC_INSTEAD_RULE;
8259 bruce@momjian.us 2434 : 369 : *instead_flag = true; /* report unqualified INSTEAD */
2435 : : }
2436 : : }
2437 : : else
8553 tgl@sss.pgh.pa.us 2438 : 192 : qsrc = QSRC_NON_INSTEAD_RULE;
2439 : :
2440 [ + + ]: 786 : if (qsrc == QSRC_QUAL_INSTEAD_RULE)
2441 : : {
2442 : : /*
2443 : : * If there are INSTEAD rules with qualifications, the original
2444 : : * query is still performed. But all the negated rule
2445 : : * qualifications of the INSTEAD rules are added so it does its
2446 : : * actions only in cases where the rule quals of all INSTEAD rules
2447 : : * are false. Think of it as the default action in a case. We save
2448 : : * this in *qual_product so RewriteQuery() can add it to the query
2449 : : * list after we mangled it up enough.
2450 : : *
2451 : : * If we have already found an unqualified INSTEAD rule, then
2452 : : * *qual_product won't be used, so don't bother building it.
2453 : : */
8259 bruce@momjian.us 2454 [ + + ]: 225 : if (!*instead_flag)
2455 : : {
8548 tgl@sss.pgh.pa.us 2456 [ + + ]: 222 : if (*qual_product == NULL)
7590 2457 : 180 : *qual_product = copyObject(parsetree);
8547 2458 : 222 : *qual_product = CopyAndAddInvertedQual(*qual_product,
2459 : : event_qual,
2460 : : rt_index,
2461 : : event);
2462 : : }
2463 : : }
2464 : :
2465 : : /* Now process the rule's actions and add them to the result list */
10416 bruce@momjian.us 2466 [ + - + + : 1593 : foreach(r, actions)
+ + ]
2467 : : {
10415 2468 : 813 : Query *rule_action = lfirst(r);
2469 : :
10071 scrappy@hub.org 2470 [ + + ]: 813 : if (rule_action->commandType == CMD_NOTHING)
2471 : 105 : continue;
2472 : :
9041 tgl@sss.pgh.pa.us 2473 : 708 : rule_action = rewriteRuleAction(parsetree, rule_action,
2474 : : event_qual, rt_index, event,
2475 : : returning_flag);
2476 : :
8553 2477 : 702 : rule_action->querySource = qsrc;
3189 2478 : 702 : rule_action->canSetTag = false; /* might change later */
2479 : :
9041 2480 : 702 : results = lappend(results, rule_action);
2481 : : }
2482 : : }
2483 : :
10416 bruce@momjian.us 2484 : 45461 : return results;
2485 : : }
2486 : :
2487 : :
2488 : : /*
2489 : : * get_view_query - get the Query from a view's _RETURN rule.
2490 : : *
2491 : : * Caller should have verified that the relation is a view, and therefore
2492 : : * we should find an ON SELECT action.
2493 : : *
2494 : : * Note that the pointer returned is into the relcache and therefore must
2495 : : * be treated as read-only to the caller and not modified or scribbled on.
2496 : : */
2497 : : Query *
4845 tgl@sss.pgh.pa.us 2498 : 2994 : get_view_query(Relation view)
2499 : : {
2500 : : int i;
2501 : :
2502 [ - + ]: 2994 : Assert(view->rd_rel->relkind == RELKIND_VIEW);
2503 : :
2504 [ + - ]: 2994 : for (i = 0; i < view->rd_rules->numLocks; i++)
2505 : : {
2506 : 2994 : RewriteRule *rule = view->rd_rules->rules[i];
2507 : :
2508 [ + - ]: 2994 : if (rule->event == CMD_SELECT)
2509 : : {
2510 : : /* A _RETURN rule should have only one action */
2511 [ - + ]: 2994 : if (list_length(rule->actions) != 1)
4845 tgl@sss.pgh.pa.us 2512 [ # # ]:UBC 0 : elog(ERROR, "invalid _RETURN rule action specification");
2513 : :
4845 tgl@sss.pgh.pa.us 2514 :CBC 2994 : return (Query *) linitial(rule->actions);
2515 : : }
2516 : : }
2517 : :
4845 tgl@sss.pgh.pa.us 2518 [ # # ]:UBC 0 : elog(ERROR, "failed to find _RETURN rule for view");
2519 : : return NULL; /* keep compiler quiet */
2520 : : }
2521 : :
2522 : :
2523 : : /*
2524 : : * view_has_instead_trigger - does view have an INSTEAD OF trigger for event?
2525 : : *
2526 : : * If it does, we don't want to treat it as auto-updatable. This test can't
2527 : : * be folded into view_query_is_auto_updatable because it's not an error
2528 : : * condition.
2529 : : *
2530 : : * For MERGE, this will return true if there is an INSTEAD OF trigger for
2531 : : * every action in mergeActionList, and false if there are any actions that
2532 : : * lack an INSTEAD OF trigger. If there are no data-modifying MERGE actions
2533 : : * (only DO NOTHING actions), true is returned so that the view is treated
2534 : : * as trigger-updatable, rather than erroring out if it's not auto-updatable.
2535 : : */
2536 : : bool
745 dean.a.rasheed@gmail 2537 :CBC 2791 : view_has_instead_trigger(Relation view, CmdType event, List *mergeActionList)
2538 : : {
4845 tgl@sss.pgh.pa.us 2539 : 2791 : TriggerDesc *trigDesc = view->trigdesc;
2540 : :
2541 [ + + + + : 2791 : switch (event)
- ]
2542 : : {
2543 : 930 : case CMD_INSERT:
2544 [ + + + - ]: 930 : if (trigDesc && trigDesc->trig_insert_instead_row)
2545 : 132 : return true;
2546 : 798 : break;
2547 : 1030 : case CMD_UPDATE:
2548 [ + + + - ]: 1030 : if (trigDesc && trigDesc->trig_update_instead_row)
2549 : 159 : return true;
2550 : 871 : break;
2551 : 306 : case CMD_DELETE:
2552 [ + + + - ]: 306 : if (trigDesc && trigDesc->trig_delete_instead_row)
2553 : 54 : return true;
2554 : 252 : break;
745 dean.a.rasheed@gmail 2555 : 525 : case CMD_MERGE:
2556 [ + - + + : 741 : foreach_node(MergeAction, action, mergeActionList)
+ + ]
2557 : : {
2558 [ + + + + : 585 : switch (action->commandType)
- ]
2559 : : {
2560 : 102 : case CMD_INSERT:
2561 [ + + + + ]: 102 : if (!trigDesc || !trigDesc->trig_insert_instead_row)
2562 : 447 : return false;
2563 : 42 : break;
2564 : 372 : case CMD_UPDATE:
2565 [ + + - + ]: 372 : if (!trigDesc || !trigDesc->trig_update_instead_row)
2566 : 318 : return false;
2567 : 54 : break;
2568 : 81 : case CMD_DELETE:
2569 [ + + + + ]: 81 : if (!trigDesc || !trigDesc->trig_delete_instead_row)
2570 : 69 : return false;
2571 : 12 : break;
2572 : 30 : case CMD_NOTHING:
2573 : : /* No trigger required */
2574 : 30 : break;
745 dean.a.rasheed@gmail 2575 :UBC 0 : default:
2576 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d", action->commandType);
2577 : : break;
2578 : : }
2579 : : }
745 dean.a.rasheed@gmail 2580 :CBC 78 : return true; /* no actions without an INSTEAD OF trigger */
4845 tgl@sss.pgh.pa.us 2581 :UBC 0 : default:
2582 [ # # ]: 0 : elog(ERROR, "unrecognized CmdType: %d", (int) event);
2583 : : break;
2584 : : }
4845 tgl@sss.pgh.pa.us 2585 :CBC 1921 : return false;
2586 : : }
2587 : :
2588 : :
2589 : : /*
2590 : : * view_col_is_auto_updatable - test whether the specified column of a view
2591 : : * is auto-updatable. Returns NULL (if the column can be updated) or a message
2592 : : * string giving the reason that it cannot be.
2593 : : *
2594 : : * The returned string has not been translated; if it is shown as an error
2595 : : * message, the caller should apply _() to translate it.
2596 : : *
2597 : : * Note that the checks performed here are local to this view. We do not check
2598 : : * whether the referenced column of the underlying base relation is updatable.
2599 : : */
2600 : : static const char *
4531 rhaas@postgresql.org 2601 : 7356 : view_col_is_auto_updatable(RangeTblRef *rtr, TargetEntry *tle)
2602 : : {
2603 : 7356 : Var *var = (Var *) tle->expr;
2604 : :
2605 : : /*
2606 : : * For now, the only updatable columns we support are those that are Vars
2607 : : * referring to user columns of the underlying base relation.
2608 : : *
2609 : : * The view targetlist may contain resjunk columns (e.g., a view defined
2610 : : * like "SELECT * FROM t ORDER BY a+b" is auto-updatable) but such columns
2611 : : * are not auto-updatable, and in fact should never appear in the outer
2612 : : * query's targetlist.
2613 : : */
2614 [ + + ]: 7356 : if (tle->resjunk)
2615 : 90 : return gettext_noop("Junk view columns are not updatable.");
2616 : :
2617 [ + + ]: 7266 : if (!IsA(var, Var) ||
2618 [ + - ]: 6531 : var->varno != rtr->rtindex ||
2619 [ - + ]: 6531 : var->varlevelsup != 0)
2620 : 735 : return gettext_noop("View columns that are not columns of their base relation are not updatable.");
2621 : :
2622 [ + + ]: 6531 : if (var->varattno < 0)
2623 : 201 : return gettext_noop("View columns that refer to system columns are not updatable.");
2624 : :
2625 [ - + ]: 6330 : if (var->varattno == 0)
4531 rhaas@postgresql.org 2626 :UBC 0 : return gettext_noop("View columns that return whole-row references are not updatable.");
2627 : :
4531 rhaas@postgresql.org 2628 :CBC 6330 : return NULL; /* the view column is updatable */
2629 : : }
2630 : :
2631 : :
2632 : : /*
2633 : : * view_query_is_auto_updatable - test whether the specified view definition
2634 : : * represents an auto-updatable view. Returns NULL (if the view can be updated)
2635 : : * or a message string giving the reason that it cannot be.
2636 : : *
2637 : : * The returned string has not been translated; if it is shown as an error
2638 : : * message, the caller should apply _() to translate it.
2639 : : *
2640 : : * If check_cols is true, the view is required to have at least one updatable
2641 : : * column (necessary for INSERT/UPDATE). Otherwise the view's columns are not
2642 : : * checked for updatability. See also view_cols_are_auto_updatable.
2643 : : *
2644 : : * Note that the checks performed here are only based on the view definition.
2645 : : * We do not check whether any base relations referred to by the view are
2646 : : * updatable.
2647 : : */
2648 : : const char *
4355 sfrost@snowman.net 2649 : 2879 : view_query_is_auto_updatable(Query *viewquery, bool check_cols)
2650 : : {
2651 : : RangeTblRef *rtr;
2652 : : RangeTblEntry *base_rte;
2653 : :
2654 : : /*----------
2655 : : * Check if the view is simply updatable. According to SQL-92 this means:
2656 : : * - No DISTINCT clause.
2657 : : * - Each TLE is a column reference, and each column appears at most once.
2658 : : * - FROM contains exactly one base relation.
2659 : : * - No GROUP BY or HAVING clauses.
2660 : : * - No set operations (UNION, INTERSECT or EXCEPT).
2661 : : * - No sub-queries in the WHERE clause that reference the target table.
2662 : : *
2663 : : * We ignore that last restriction since it would be complex to enforce
2664 : : * and there isn't any actual benefit to disallowing sub-queries. (The
2665 : : * semantic issues that the standard is presumably concerned about don't
2666 : : * arise in Postgres, since any such sub-query will not see any updates
2667 : : * executed by the outer query anyway, thanks to MVCC snapshotting.)
2668 : : *
2669 : : * We also relax the second restriction by supporting part of SQL:1999
2670 : : * feature T111, which allows for a mix of updatable and non-updatable
2671 : : * columns, provided that an INSERT or UPDATE doesn't attempt to assign to
2672 : : * a non-updatable column.
2673 : : *
2674 : : * In addition we impose these constraints, involving features that are
2675 : : * not part of SQL-92:
2676 : : * - No CTEs (WITH clauses).
2677 : : * - No OFFSET or LIMIT clauses (this matches a SQL:2008 restriction).
2678 : : * - No system columns (including whole-row references) in the tlist.
2679 : : * - No window functions in the tlist.
2680 : : * - No set-returning functions in the tlist.
2681 : : *
2682 : : * Note that we do these checks without recursively expanding the view.
2683 : : * If the base relation is a view, we'll recursively deal with it later.
2684 : : *----------
2685 : : */
4845 tgl@sss.pgh.pa.us 2686 [ + + ]: 2879 : if (viewquery->distinctClause != NIL)
2687 : 36 : return gettext_noop("Views containing DISTINCT are not automatically updatable.");
2688 : :
3956 andres@anarazel.de 2689 [ + + - + ]: 2843 : if (viewquery->groupClause != NIL || viewquery->groupingSets)
4845 tgl@sss.pgh.pa.us 2690 : 18 : return gettext_noop("Views containing GROUP BY are not automatically updatable.");
2691 : :
2692 [ + + ]: 2825 : if (viewquery->havingQual != NULL)
2693 : 15 : return gettext_noop("Views containing HAVING are not automatically updatable.");
2694 : :
2695 [ + + ]: 2810 : if (viewquery->setOperations != NULL)
4718 peter_e@gmx.net 2696 : 18 : return gettext_noop("Views containing UNION, INTERSECT, or EXCEPT are not automatically updatable.");
2697 : :
4845 tgl@sss.pgh.pa.us 2698 [ + + ]: 2792 : if (viewquery->cteList != NIL)
2699 : 18 : return gettext_noop("Views containing WITH are not automatically updatable.");
2700 : :
2701 [ + + + + ]: 2774 : if (viewquery->limitOffset != NULL || viewquery->limitCount != NULL)
2702 : 288 : return gettext_noop("Views containing LIMIT or OFFSET are not automatically updatable.");
2703 : :
2704 : : /*
2705 : : * We must not allow window functions or set returning functions in the
2706 : : * targetlist. Otherwise we might end up inserting them into the quals of
2707 : : * the main query. We must also check for aggregates in the targetlist in
2708 : : * case they appear without a GROUP BY.
2709 : : *
2710 : : * These restrictions ensure that each row of the view corresponds to a
2711 : : * unique row in the underlying base relation.
2712 : : */
4531 rhaas@postgresql.org 2713 [ + + ]: 2486 : if (viewquery->hasAggs)
4216 peter_e@gmx.net 2714 : 15 : return gettext_noop("Views that return aggregate functions are not automatically updatable.");
2715 : :
4531 rhaas@postgresql.org 2716 [ + + ]: 2471 : if (viewquery->hasWindowFuncs)
4216 peter_e@gmx.net 2717 : 18 : return gettext_noop("Views that return window functions are not automatically updatable.");
2718 : :
3470 tgl@sss.pgh.pa.us 2719 [ + + ]: 2453 : if (viewquery->hasTargetSRFs)
4531 rhaas@postgresql.org 2720 : 21 : return gettext_noop("Views that return set-returning functions are not automatically updatable.");
2721 : :
2722 : : /*
2723 : : * The view query should select from a single base relation, which must be
2724 : : * a table or another view.
2725 : : */
4845 tgl@sss.pgh.pa.us 2726 [ + + ]: 2432 : if (list_length(viewquery->jointree->fromlist) != 1)
2727 : 33 : return gettext_noop("Views that do not select from a single table or view are not automatically updatable.");
2728 : :
2729 : 2399 : rtr = (RangeTblRef *) linitial(viewquery->jointree->fromlist);
2730 [ - + ]: 2399 : if (!IsA(rtr, RangeTblRef))
4845 tgl@sss.pgh.pa.us 2731 :UBC 0 : return gettext_noop("Views that do not select from a single table or view are not automatically updatable.");
2732 : :
4845 tgl@sss.pgh.pa.us 2733 :CBC 2399 : base_rte = rt_fetch(rtr->rtindex, viewquery->rtable);
2734 [ + + ]: 2399 : if (base_rte->rtekind != RTE_RELATION ||
2735 [ + + ]: 2342 : (base_rte->relkind != RELKIND_RELATION &&
4659 2736 [ + + ]: 904 : base_rte->relkind != RELKIND_FOREIGN_TABLE &&
3337 rhaas@postgresql.org 2737 [ + + ]: 893 : base_rte->relkind != RELKIND_VIEW &&
2738 [ + + ]: 128 : base_rte->relkind != RELKIND_PARTITIONED_TABLE))
4845 tgl@sss.pgh.pa.us 2739 : 78 : return gettext_noop("Views that do not select from a single table or view are not automatically updatable.");
2740 : :
3957 simon@2ndQuadrant.co 2741 [ + + ]: 2321 : if (base_rte->tablesample)
2742 : 3 : return gettext_noop("Views containing TABLESAMPLE are not automatically updatable.");
2743 : :
2744 : : /*
2745 : : * Check that the view has at least one updatable column. This is required
2746 : : * for INSERT/UPDATE but not for DELETE.
2747 : : */
4531 rhaas@postgresql.org 2748 [ + + ]: 2318 : if (check_cols)
2749 : : {
2750 : : ListCell *cell;
2751 : : bool found;
2752 : :
2753 : 1601 : found = false;
2754 [ + - + - : 1694 : foreach(cell, viewquery->targetList)
+ - ]
2755 : : {
2756 : 1694 : TargetEntry *tle = (TargetEntry *) lfirst(cell);
2757 : :
2758 [ + + ]: 1694 : if (view_col_is_auto_updatable(rtr, tle) == NULL)
2759 : : {
2760 : 1601 : found = true;
2761 : 1601 : break;
2762 : : }
2763 : : }
2764 : :
2765 [ - + ]: 1601 : if (!found)
4531 rhaas@postgresql.org 2766 :UBC 0 : return gettext_noop("Views that have no updatable columns are not automatically updatable.");
2767 : : }
2768 : :
4531 rhaas@postgresql.org 2769 :CBC 2318 : return NULL; /* the view is updatable */
2770 : : }
2771 : :
2772 : :
2773 : : /*
2774 : : * view_cols_are_auto_updatable - test whether all of the required columns of
2775 : : * an auto-updatable view are actually updatable. Returns NULL (if all the
2776 : : * required columns can be updated) or a message string giving the reason that
2777 : : * they cannot be.
2778 : : *
2779 : : * The returned string has not been translated; if it is shown as an error
2780 : : * message, the caller should apply _() to translate it.
2781 : : *
2782 : : * This should be used for INSERT/UPDATE to ensure that we don't attempt to
2783 : : * assign to any non-updatable columns.
2784 : : *
2785 : : * Additionally it may be used to retrieve the set of updatable columns in the
2786 : : * view, or if one or more of the required columns is not updatable, the name
2787 : : * of the first offending non-updatable column.
2788 : : *
2789 : : * The caller must have already verified that this is an auto-updatable view
2790 : : * using view_query_is_auto_updatable.
2791 : : *
2792 : : * Note that the checks performed here are only based on the view definition.
2793 : : * We do not check whether the referenced columns of the base relation are
2794 : : * updatable.
2795 : : */
2796 : : static const char *
2797 : 2050 : view_cols_are_auto_updatable(Query *viewquery,
2798 : : Bitmapset *required_cols,
2799 : : Bitmapset **updatable_cols,
2800 : : char **non_updatable_col)
2801 : : {
2802 : : RangeTblRef *rtr;
2803 : : AttrNumber col;
2804 : : ListCell *cell;
2805 : :
2806 : : /*
2807 : : * The caller should have verified that this view is auto-updatable and so
2808 : : * there should be a single base relation.
2809 : : */
2810 [ - + ]: 2050 : Assert(list_length(viewquery->jointree->fromlist) == 1);
3261 tgl@sss.pgh.pa.us 2811 : 2050 : rtr = linitial_node(RangeTblRef, viewquery->jointree->fromlist);
2812 : :
2813 : : /* Initialize the optional return values */
4531 rhaas@postgresql.org 2814 [ + + ]: 2050 : if (updatable_cols != NULL)
2815 : 525 : *updatable_cols = NULL;
2816 [ + + ]: 2050 : if (non_updatable_col != NULL)
2817 : 1525 : *non_updatable_col = NULL;
2818 : :
2819 : : /* Test each view column for updatability */
2820 : 2050 : col = -FirstLowInvalidHeapAttributeNumber;
2821 [ + - + + : 7652 : foreach(cell, viewquery->targetList)
+ + ]
2822 : : {
2823 : 5662 : TargetEntry *tle = (TargetEntry *) lfirst(cell);
2824 : : const char *col_update_detail;
2825 : :
2826 : 5662 : col++;
2827 : 5662 : col_update_detail = view_col_is_auto_updatable(rtr, tle);
2828 : :
2829 [ + + ]: 5662 : if (col_update_detail == NULL)
2830 : : {
2831 : : /* The column is updatable */
2832 [ + + ]: 4729 : if (updatable_cols != NULL)
2833 : 1068 : *updatable_cols = bms_add_member(*updatable_cols, col);
2834 : : }
2835 [ + + ]: 933 : else if (bms_is_member(col, required_cols))
2836 : : {
2837 : : /* The required column is not updatable */
2838 [ + - ]: 60 : if (non_updatable_col != NULL)
2839 : 60 : *non_updatable_col = tle->resname;
2840 : 60 : return col_update_detail;
2841 : : }
2842 : : }
2843 : :
4331 bruce@momjian.us 2844 : 1990 : return NULL; /* all the required view columns are updatable */
2845 : : }
2846 : :
2847 : :
2848 : : /*
2849 : : * relation_is_updatable - determine which update events the specified
2850 : : * relation supports.
2851 : : *
2852 : : * Note that views may contain a mix of updatable and non-updatable columns.
2853 : : * For a view to support INSERT/UPDATE it must have at least one updatable
2854 : : * column, but there is no such restriction for DELETE. If include_cols is
2855 : : * non-NULL, then only the specified columns are considered when testing for
2856 : : * updatability.
2857 : : *
2858 : : * Unlike the preceding functions, this does recurse to look at a view's
2859 : : * base relations, so it needs to detect recursion. To do that, we pass
2860 : : * a list of currently-considered outer relations. External callers need
2861 : : * only pass NIL.
2862 : : *
2863 : : * This is used for the information_schema views, which have separate concepts
2864 : : * of "updatable" and "trigger updatable". A relation is "updatable" if it
2865 : : * can be updated without the need for triggers (either because it has a
2866 : : * suitable RULE, or because it is simple enough to be automatically updated).
2867 : : * A relation is "trigger updatable" if it has a suitable INSTEAD OF trigger.
2868 : : * The SQL standard regards this as not necessarily updatable, presumably
2869 : : * because there is no way of knowing what the trigger will actually do.
2870 : : * The information_schema views therefore call this function with
2871 : : * include_triggers = false. However, other callers might only care whether
2872 : : * data-modifying SQL will work, so they can pass include_triggers = true
2873 : : * to have trigger updatability included in the result.
2874 : : *
2875 : : * The return value is a bitmask of rule event numbers indicating which of
2876 : : * the INSERT, UPDATE and DELETE operations are supported. (We do it this way
2877 : : * so that we can test for UPDATE plus DELETE support in a single call.)
2878 : : */
2879 : : int
4531 rhaas@postgresql.org 2880 : 1056 : relation_is_updatable(Oid reloid,
2881 : : List *outer_reloids,
2882 : : bool include_triggers,
2883 : : Bitmapset *include_cols)
2884 : : {
4659 tgl@sss.pgh.pa.us 2885 : 1056 : int events = 0;
2886 : : Relation rel;
2887 : : RuleLock *rulelocks;
2888 : :
2889 : : #define ALL_EVENTS ((1 << CMD_INSERT) | (1 << CMD_UPDATE) | (1 << CMD_DELETE))
2890 : :
2891 : : /* Since this function recurses, it could be driven to stack overflow */
2306 2892 : 1056 : check_stack_depth();
2893 : :
4845 2894 : 1056 : rel = try_relation_open(reloid, AccessShareLock);
2895 : :
2896 : : /*
2897 : : * If the relation doesn't exist, return zero rather than throwing an
2898 : : * error. This is helpful since scanning an information_schema view under
2899 : : * MVCC rules can result in referencing rels that have actually been
2900 : : * deleted already.
2901 : : */
2902 [ - + ]: 1056 : if (rel == NULL)
4659 tgl@sss.pgh.pa.us 2903 :UBC 0 : return 0;
2904 : :
2905 : : /* If we detect a recursive view, report that it is not updatable */
2306 tgl@sss.pgh.pa.us 2906 [ - + ]:CBC 1056 : if (list_member_oid(outer_reloids, RelationGetRelid(rel)))
2907 : : {
2306 tgl@sss.pgh.pa.us 2908 :UBC 0 : relation_close(rel, AccessShareLock);
2909 : 0 : return 0;
2910 : : }
2911 : :
2912 : : /* If the relation is a table, it is always updatable */
3197 dean.a.rasheed@gmail 2913 [ + - ]:CBC 1056 : if (rel->rd_rel->relkind == RELKIND_RELATION ||
2914 [ + + ]: 1056 : rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
2915 : : {
4659 tgl@sss.pgh.pa.us 2916 : 9 : relation_close(rel, AccessShareLock);
2917 : 9 : return ALL_EVENTS;
2918 : : }
2919 : :
2920 : : /* Look for unconditional DO INSTEAD rules, and note supported events */
4845 2921 : 1047 : rulelocks = rel->rd_rules;
2922 [ + - ]: 1047 : if (rulelocks != NULL)
2923 : : {
2924 : : int i;
2925 : :
2926 [ + + ]: 2280 : for (i = 0; i < rulelocks->numLocks; i++)
2927 : : {
2928 [ + + ]: 1233 : if (rulelocks->rules[i]->isInstead &&
2929 [ + - ]: 1227 : rulelocks->rules[i]->qual == NULL)
2930 : : {
4659 2931 : 1227 : events |= ((1 << rulelocks->rules[i]->event) & ALL_EVENTS);
2932 : : }
2933 : : }
2934 : :
2935 : : /* If we have rules for all events, we're done */
2936 [ + + ]: 1047 : if (events == ALL_EVENTS)
2937 : : {
4845 2938 : 30 : relation_close(rel, AccessShareLock);
4659 2939 : 30 : return events;
2940 : : }
2941 : : }
2942 : :
2943 : : /* Similarly look for INSTEAD OF triggers, if they are to be included */
2944 [ - + ]: 1017 : if (include_triggers)
2945 : : {
4659 tgl@sss.pgh.pa.us 2946 :UBC 0 : TriggerDesc *trigDesc = rel->trigdesc;
2947 : :
2948 [ # # ]: 0 : if (trigDesc)
2949 : : {
2950 [ # # ]: 0 : if (trigDesc->trig_insert_instead_row)
2951 : 0 : events |= (1 << CMD_INSERT);
2952 [ # # ]: 0 : if (trigDesc->trig_update_instead_row)
2953 : 0 : events |= (1 << CMD_UPDATE);
2954 [ # # ]: 0 : if (trigDesc->trig_delete_instead_row)
2955 : 0 : events |= (1 << CMD_DELETE);
2956 : :
2957 : : /* If we have triggers for all events, we're done */
2958 [ # # ]: 0 : if (events == ALL_EVENTS)
2959 : : {
2960 : 0 : relation_close(rel, AccessShareLock);
2961 : 0 : return events;
2962 : : }
2963 : : }
2964 : : }
2965 : :
2966 : : /* If this is a foreign table, check which update events it supports */
4659 tgl@sss.pgh.pa.us 2967 [ - + ]:CBC 1017 : if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
2968 : : {
4659 tgl@sss.pgh.pa.us 2969 :UBC 0 : FdwRoutine *fdwroutine = GetFdwRoutineForRelation(rel, false);
2970 : :
2971 [ # # ]: 0 : if (fdwroutine->IsForeignRelUpdatable != NULL)
2972 : 0 : events |= fdwroutine->IsForeignRelUpdatable(rel);
2973 : : else
2974 : : {
2975 : : /* Assume presence of executor functions is sufficient */
2976 [ # # ]: 0 : if (fdwroutine->ExecForeignInsert != NULL)
2977 : 0 : events |= (1 << CMD_INSERT);
2978 [ # # ]: 0 : if (fdwroutine->ExecForeignUpdate != NULL)
2979 : 0 : events |= (1 << CMD_UPDATE);
2980 [ # # ]: 0 : if (fdwroutine->ExecForeignDelete != NULL)
2981 : 0 : events |= (1 << CMD_DELETE);
2982 : : }
2983 : :
2984 : 0 : relation_close(rel, AccessShareLock);
2985 : 0 : return events;
2986 : : }
2987 : :
2988 : : /* Check if this is an automatically updatable view */
4531 rhaas@postgresql.org 2989 [ + - ]:CBC 1017 : if (rel->rd_rel->relkind == RELKIND_VIEW)
2990 : : {
2991 : 1017 : Query *viewquery = get_view_query(rel);
2992 : :
4355 sfrost@snowman.net 2993 [ + + ]: 1017 : if (view_query_is_auto_updatable(viewquery, false) == NULL)
2994 : : {
2995 : : Bitmapset *updatable_cols;
2996 : : int auto_events;
2997 : : RangeTblRef *rtr;
2998 : : RangeTblEntry *base_rte;
2999 : : Oid baseoid;
3000 : :
3001 : : /*
3002 : : * Determine which of the view's columns are updatable. If there
3003 : : * are none within the set of columns we are looking at, then the
3004 : : * view doesn't support INSERT/UPDATE, but it may still support
3005 : : * DELETE.
3006 : : */
4531 rhaas@postgresql.org 3007 : 525 : view_cols_are_auto_updatable(viewquery, NULL,
3008 : : &updatable_cols, NULL);
3009 : :
3010 [ + + ]: 525 : if (include_cols != NULL)
3011 : 288 : updatable_cols = bms_int_members(updatable_cols, include_cols);
3012 : :
3013 [ + + ]: 525 : if (bms_is_empty(updatable_cols))
3189 tgl@sss.pgh.pa.us 3014 : 75 : auto_events = (1 << CMD_DELETE); /* May support DELETE */
3015 : : else
3016 : 450 : auto_events = ALL_EVENTS; /* May support all events */
3017 : :
3018 : : /*
3019 : : * The base relation must also support these update commands.
3020 : : * Tables are always updatable, but for any other kind of base
3021 : : * relation we must do a recursive check limited to the columns
3022 : : * referenced by the locally updatable columns in this view.
3023 : : */
4531 rhaas@postgresql.org 3024 : 525 : rtr = (RangeTblRef *) linitial(viewquery->jointree->fromlist);
3025 : 525 : base_rte = rt_fetch(rtr->rtindex, viewquery->rtable);
3026 [ - + ]: 525 : Assert(base_rte->rtekind == RTE_RELATION);
3027 : :
3197 dean.a.rasheed@gmail 3028 [ + + ]: 525 : if (base_rte->relkind != RELKIND_RELATION &&
3029 [ + + ]: 291 : base_rte->relkind != RELKIND_PARTITIONED_TABLE)
3030 : : {
4531 rhaas@postgresql.org 3031 : 276 : baseoid = base_rte->relid;
2306 tgl@sss.pgh.pa.us 3032 : 276 : outer_reloids = lappend_oid(outer_reloids,
3033 : : RelationGetRelid(rel));
4531 rhaas@postgresql.org 3034 : 276 : include_cols = adjust_view_column_set(updatable_cols,
3035 : : viewquery->targetList);
3036 : 276 : auto_events &= relation_is_updatable(baseoid,
3037 : : outer_reloids,
3038 : : include_triggers,
3039 : : include_cols);
2306 tgl@sss.pgh.pa.us 3040 : 276 : outer_reloids = list_delete_last(outer_reloids);
3041 : : }
4531 rhaas@postgresql.org 3042 : 525 : events |= auto_events;
3043 : : }
3044 : : }
3045 : :
3046 : : /* If we reach here, the relation may support some update commands */
4845 tgl@sss.pgh.pa.us 3047 : 1017 : relation_close(rel, AccessShareLock);
4659 3048 : 1017 : return events;
3049 : : }
3050 : :
3051 : :
3052 : : /*
3053 : : * adjust_view_column_set - map a set of column numbers according to targetlist
3054 : : *
3055 : : * This is used with simply-updatable views to map column-permissions sets for
3056 : : * the view columns onto the matching columns in the underlying base relation.
3057 : : * Relevant entries in the targetlist must be plain Vars of the underlying
3058 : : * relation (as per the checks above in view_query_is_auto_updatable).
3059 : : */
3060 : : static Bitmapset *
4845 3061 : 3584 : adjust_view_column_set(Bitmapset *cols, List *targetlist)
3062 : : {
3063 : 3584 : Bitmapset *result = NULL;
3064 : : int col;
3065 : :
4125 3066 : 3584 : col = -1;
3067 [ + + ]: 6218 : while ((col = bms_next_member(cols, col)) >= 0)
3068 : : {
3069 : : /* bit numbers are offset by FirstLowInvalidHeapAttributeNumber */
4845 3070 : 2634 : AttrNumber attno = col + FirstLowInvalidHeapAttributeNumber;
3071 : :
3072 [ - + ]: 2634 : if (attno == InvalidAttrNumber)
3073 : : {
3074 : : /*
3075 : : * There's a whole-row reference to the view. For permissions
3076 : : * purposes, treat it as a reference to each column available from
3077 : : * the view. (We should *not* convert this to a whole-row
3078 : : * reference to the base relation, since the view may not touch
3079 : : * all columns of the base relation.)
3080 : : */
3081 : : ListCell *lc;
3082 : :
4845 tgl@sss.pgh.pa.us 3083 [ # # # # :UBC 0 : foreach(lc, targetlist)
# # ]
3084 : : {
3261 3085 : 0 : TargetEntry *tle = lfirst_node(TargetEntry, lc);
3086 : : Var *var;
3087 : :
4845 3088 [ # # ]: 0 : if (tle->resjunk)
3089 : 0 : continue;
3309 peter_e@gmx.net 3090 : 0 : var = castNode(Var, tle->expr);
4845 tgl@sss.pgh.pa.us 3091 : 0 : result = bms_add_member(result,
3189 3092 : 0 : var->varattno - FirstLowInvalidHeapAttributeNumber);
3093 : : }
3094 : : }
3095 : : else
3096 : : {
3097 : : /*
3098 : : * Views do not have system columns, so we do not expect to see
3099 : : * any other system attnos here. If we do find one, the error
3100 : : * case will apply.
3101 : : */
4845 tgl@sss.pgh.pa.us 3102 :CBC 2634 : TargetEntry *tle = get_tle_by_resno(targetlist, attno);
3103 : :
3104 [ + - + - : 2634 : if (tle != NULL && !tle->resjunk && IsA(tle->expr, Var))
+ - ]
3105 : 2634 : {
3106 : 2634 : Var *var = (Var *) tle->expr;
3107 : :
3108 : 2634 : result = bms_add_member(result,
3189 3109 : 2634 : var->varattno - FirstLowInvalidHeapAttributeNumber);
3110 : : }
3111 : : else
4845 tgl@sss.pgh.pa.us 3112 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3113 : : attno);
3114 : : }
3115 : : }
3116 : :
4845 tgl@sss.pgh.pa.us 3117 :CBC 3584 : return result;
3118 : : }
3119 : :
3120 : :
3121 : : /*
3122 : : * error_view_not_updatable -
3123 : : * Report an error due to an attempt to update a non-updatable view.
3124 : : *
3125 : : * Generally this is expected to be called from the rewriter, with suitable
3126 : : * error detail explaining why the view is not updatable. Note, however, that
3127 : : * the executor also performs a just-in-case check that the target view is
3128 : : * updatable. That check is expected to never fail, but if it does, it will
3129 : : * call this function with NULL error detail --- see CheckValidResultRel().
3130 : : *
3131 : : * Note: for MERGE, at least one of the actions in mergeActionList is expected
3132 : : * to lack a suitable INSTEAD OF trigger --- see view_has_instead_trigger().
3133 : : */
3134 : : void
745 dean.a.rasheed@gmail 3135 : 78 : error_view_not_updatable(Relation view,
3136 : : CmdType command,
3137 : : List *mergeActionList,
3138 : : const char *detail)
3139 : : {
3140 : 78 : TriggerDesc *trigDesc = view->trigdesc;
3141 : :
3142 [ + + + + : 78 : switch (command)
- ]
3143 : : {
3144 : 12 : case CMD_INSERT:
3145 [ + - + - ]: 12 : ereport(ERROR,
3146 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3147 : : errmsg("cannot insert into view \"%s\"",
3148 : : RelationGetRelationName(view)),
3149 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3150 : : errhint("To enable inserting into the view, provide an INSTEAD OF INSERT trigger or an unconditional ON INSERT DO INSTEAD rule."));
3151 : : break;
3152 : 27 : case CMD_UPDATE:
3153 [ + - + - ]: 27 : ereport(ERROR,
3154 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3155 : : errmsg("cannot update view \"%s\"",
3156 : : RelationGetRelationName(view)),
3157 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3158 : : errhint("To enable updating the view, provide an INSTEAD OF UPDATE trigger or an unconditional ON UPDATE DO INSTEAD rule."));
3159 : : break;
3160 : 24 : case CMD_DELETE:
3161 [ + - + - ]: 24 : ereport(ERROR,
3162 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3163 : : errmsg("cannot delete from view \"%s\"",
3164 : : RelationGetRelationName(view)),
3165 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3166 : : errhint("To enable deleting from the view, provide an INSTEAD OF DELETE trigger or an unconditional ON DELETE DO INSTEAD rule."));
3167 : : break;
3168 : 15 : case CMD_MERGE:
3169 : :
3170 : : /*
3171 : : * Note that the error hints here differ from above, since MERGE
3172 : : * doesn't support rules.
3173 : : */
3174 [ + - + - : 18 : foreach_node(MergeAction, action, mergeActionList)
+ - ]
3175 : : {
3176 [ + + + - : 18 : switch (action->commandType)
- ]
3177 : : {
3178 : 6 : case CMD_INSERT:
3179 [ + + + - ]: 6 : if (!trigDesc || !trigDesc->trig_insert_instead_row)
3180 [ + - + - ]: 6 : ereport(ERROR,
3181 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3182 : : errmsg("cannot insert into view \"%s\"",
3183 : : RelationGetRelationName(view)),
3184 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3185 : : errhint("To enable inserting into the view using MERGE, provide an INSTEAD OF INSERT trigger."));
745 dean.a.rasheed@gmail 3186 :UBC 0 : break;
745 dean.a.rasheed@gmail 3187 :CBC 6 : case CMD_UPDATE:
3188 [ + + - + ]: 6 : if (!trigDesc || !trigDesc->trig_update_instead_row)
3189 [ + - + - ]: 3 : ereport(ERROR,
3190 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3191 : : errmsg("cannot update view \"%s\"",
3192 : : RelationGetRelationName(view)),
3193 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3194 : : errhint("To enable updating the view using MERGE, provide an INSTEAD OF UPDATE trigger."));
3195 : 3 : break;
3196 : 6 : case CMD_DELETE:
3197 [ + + + - ]: 6 : if (!trigDesc || !trigDesc->trig_delete_instead_row)
3198 [ + - + - ]: 6 : ereport(ERROR,
3199 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3200 : : errmsg("cannot delete from view \"%s\"",
3201 : : RelationGetRelationName(view)),
3202 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3203 : : errhint("To enable deleting from the view using MERGE, provide an INSTEAD OF DELETE trigger."));
745 dean.a.rasheed@gmail 3204 :UBC 0 : break;
3205 : 0 : case CMD_NOTHING:
3206 : 0 : break;
3207 : 0 : default:
3208 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d", action->commandType);
3209 : : break;
3210 : : }
3211 : : }
3212 : 0 : break;
3213 : 0 : default:
3214 [ # # ]: 0 : elog(ERROR, "unrecognized CmdType: %d", (int) command);
3215 : : break;
3216 : : }
3217 : 0 : }
3218 : :
3219 : :
3220 : : /*
3221 : : * rewriteTargetView -
3222 : : * Attempt to rewrite a query where the target relation is a view, so that
3223 : : * the view's base relation becomes the target relation.
3224 : : *
3225 : : * Note that the base relation here may itself be a view, which may or may not
3226 : : * have INSTEAD OF triggers or rules to handle the update. That is handled by
3227 : : * the recursion in RewriteQuery.
3228 : : */
3229 : : static Query *
4845 tgl@sss.pgh.pa.us 3230 :CBC 1789 : rewriteTargetView(Query *parsetree, Relation view)
3231 : : {
3232 : : Query *viewquery;
3233 : : bool insert_or_update;
3234 : : const char *auto_update_detail;
3235 : : RangeTblRef *rtr;
3236 : : int base_rt_index;
3237 : : int new_rt_index;
3238 : : RangeTblEntry *base_rte;
3239 : : RangeTblEntry *view_rte;
3240 : : RangeTblEntry *new_rte;
3241 : : RTEPermissionInfo *base_perminfo;
3242 : : RTEPermissionInfo *view_perminfo;
3243 : : RTEPermissionInfo *new_perminfo;
3244 : : Relation base_rel;
3245 : : List *view_targetlist;
3246 : : ListCell *lc;
3247 : :
3248 : : /*
3249 : : * Get the Query from the view's ON SELECT rule. We're going to munge the
3250 : : * Query to change the view's base relation into the target relation,
3251 : : * along with various other changes along the way, so we need to make a
3252 : : * copy of it (get_view_query() returns a pointer into the relcache, so we
3253 : : * have to treat it as read-only).
3254 : : */
3737 sfrost@snowman.net 3255 : 1789 : viewquery = copyObject(get_view_query(view));
3256 : :
3257 : : /* Locate RTE and perminfo describing the view in the outer query */
603 tgl@sss.pgh.pa.us 3258 : 1789 : view_rte = rt_fetch(parsetree->resultRelation, parsetree->rtable);
3259 : 1789 : view_perminfo = getRTEPermissionInfo(parsetree->rteperminfos, view_rte);
3260 : :
3261 : : /*
3262 : : * Are we doing INSERT/UPDATE, or MERGE containing INSERT/UPDATE? If so,
3263 : : * various additional checks on the view columns need to be applied, and
3264 : : * any view CHECK OPTIONs need to be enforced.
3265 : : */
745 dean.a.rasheed@gmail 3266 : 1789 : insert_or_update =
3267 [ + + ]: 2933 : (parsetree->commandType == CMD_INSERT ||
3268 [ + + ]: 1144 : parsetree->commandType == CMD_UPDATE);
3269 : :
3270 [ + + ]: 1789 : if (parsetree->commandType == CMD_MERGE)
3271 : : {
3272 [ + - + + : 963 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3273 : : {
3274 [ + + ]: 471 : if (action->commandType == CMD_INSERT ||
3275 [ + + ]: 417 : action->commandType == CMD_UPDATE)
3276 : : {
3277 : 402 : insert_or_update = true;
4845 tgl@sss.pgh.pa.us 3278 : 402 : break;
3279 : : }
3280 : : }
3281 : : }
3282 : :
3283 : : /* Check if the expansion of non-system views are restricted */
587 msawada@postgresql.o 3284 [ + + + - : 1789 : if (unlikely((restrict_nonsystem_relation_kind & RESTRICT_RELKIND_VIEW) != 0 &&
+ + ]
3285 : : RelationGetRelid(view) >= FirstNormalObjectId))
3286 [ + - ]: 3 : ereport(ERROR,
3287 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3288 : : errmsg("access to non-system view \"%s\" is restricted",
3289 : : RelationGetRelationName(view))));
3290 : :
3291 : : /*
3292 : : * The view must be updatable, else fail.
3293 : : *
3294 : : * If we are doing INSERT/UPDATE (or MERGE containing INSERT/UPDATE), we
3295 : : * also check that there is at least one updatable column.
3296 : : */
3297 : : auto_update_detail =
745 dean.a.rasheed@gmail 3298 : 1786 : view_query_is_auto_updatable(viewquery, insert_or_update);
3299 : :
3300 [ + + ]: 1786 : if (auto_update_detail)
3301 : 69 : error_view_not_updatable(view,
3302 : : parsetree->commandType,
3303 : : parsetree->mergeActionList,
3304 : : auto_update_detail);
3305 : :
3306 : : /*
3307 : : * For INSERT/UPDATE (or MERGE containing INSERT/UPDATE) the modified
3308 : : * columns must all be updatable.
3309 : : */
3310 [ + + ]: 1717 : if (insert_or_update)
3311 : : {
3312 : : Bitmapset *modified_cols;
3313 : : char *non_updatable_col;
3314 : :
3315 : : /*
3316 : : * Compute the set of modified columns as those listed in the result
3317 : : * RTE's insertedCols and/or updatedCols sets plus those that are
3318 : : * targets of the query's targetlist(s). We must consider the query's
3319 : : * targetlist because rewriteTargetListIU may have added additional
3320 : : * targetlist entries for view defaults, and these must also be
3321 : : * updatable. But rewriteTargetListIU can also remove entries if they
3322 : : * are DEFAULT markers and the column's default is NULL, so
3323 : : * considering only the targetlist would also be wrong.
3324 : : */
603 tgl@sss.pgh.pa.us 3325 : 1525 : modified_cols = bms_union(view_perminfo->insertedCols,
3326 : 1525 : view_perminfo->updatedCols);
3327 : :
4531 rhaas@postgresql.org 3328 [ + + + + : 3241 : foreach(lc, parsetree->targetList)
+ + ]
3329 : : {
3330 : 1716 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3331 : :
3332 [ + - ]: 1716 : if (!tle->resjunk)
3333 : 1716 : modified_cols = bms_add_member(modified_cols,
3189 tgl@sss.pgh.pa.us 3334 : 1716 : tle->resno - FirstLowInvalidHeapAttributeNumber);
3335 : : }
3336 : :
3964 andres@anarazel.de 3337 [ + + ]: 1525 : if (parsetree->onConflict)
3338 : : {
3339 [ + + + + : 210 : foreach(lc, parsetree->onConflict->onConflictSet)
+ + ]
3340 : : {
3341 : 81 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3342 : :
3343 [ + - ]: 81 : if (!tle->resjunk)
3344 : 81 : modified_cols = bms_add_member(modified_cols,
3189 tgl@sss.pgh.pa.us 3345 : 81 : tle->resno - FirstLowInvalidHeapAttributeNumber);
3346 : : }
3347 : : }
3348 : :
745 dean.a.rasheed@gmail 3349 [ + + + + : 3539 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3350 : : {
3351 [ + + ]: 489 : if (action->commandType == CMD_INSERT ||
3352 [ + + ]: 384 : action->commandType == CMD_UPDATE)
3353 : : {
3354 [ + - + + : 1473 : foreach_node(TargetEntry, tle, action->targetList)
+ + ]
3355 : : {
3356 [ + - ]: 567 : if (!tle->resjunk)
3357 : 567 : modified_cols = bms_add_member(modified_cols,
3358 : 567 : tle->resno - FirstLowInvalidHeapAttributeNumber);
3359 : : }
3360 : : }
3361 : : }
3362 : :
4531 rhaas@postgresql.org 3363 : 1525 : auto_update_detail = view_cols_are_auto_updatable(viewquery,
3364 : : modified_cols,
3365 : : NULL,
3366 : : &non_updatable_col);
3367 [ + + ]: 1525 : if (auto_update_detail)
3368 : : {
3369 : : /*
3370 : : * This is a different error, caused by an attempt to update a
3371 : : * non-updatable column in an otherwise updatable view.
3372 : : */
3373 [ + + + - ]: 60 : switch (parsetree->commandType)
3374 : : {
3375 : 36 : case CMD_INSERT:
3376 [ + - ]: 36 : ereport(ERROR,
3377 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3378 : : errmsg("cannot insert into column \"%s\" of view \"%s\"",
3379 : : non_updatable_col,
3380 : : RelationGetRelationName(view)),
3381 : : errdetail_internal("%s", _(auto_update_detail))));
3382 : : break;
3383 : 21 : case CMD_UPDATE:
3384 [ + - ]: 21 : ereport(ERROR,
3385 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3386 : : errmsg("cannot update column \"%s\" of view \"%s\"",
3387 : : non_updatable_col,
3388 : : RelationGetRelationName(view)),
3389 : : errdetail_internal("%s", _(auto_update_detail))));
3390 : : break;
745 dean.a.rasheed@gmail 3391 : 3 : case CMD_MERGE:
3392 [ + - ]: 3 : ereport(ERROR,
3393 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3394 : : errmsg("cannot merge into column \"%s\" of view \"%s\"",
3395 : : non_updatable_col,
3396 : : RelationGetRelationName(view)),
3397 : : errdetail_internal("%s", _(auto_update_detail))));
3398 : : break;
4531 rhaas@postgresql.org 3399 :UBC 0 : default:
3400 [ # # ]: 0 : elog(ERROR, "unrecognized CmdType: %d",
3401 : : (int) parsetree->commandType);
3402 : : break;
3403 : : }
3404 : : }
3405 : : }
3406 : :
3407 : : /*
3408 : : * For MERGE, there must not be any INSTEAD OF triggers on an otherwise
3409 : : * updatable view. The caller already checked that there isn't a full set
3410 : : * of INSTEAD OF triggers, so this is to guard against having a partial
3411 : : * set (mixing auto-update and trigger-update actions in a single command
3412 : : * isn't supported).
3413 : : */
745 dean.a.rasheed@gmail 3414 [ + + ]:CBC 1657 : if (parsetree->commandType == CMD_MERGE)
3415 : : {
3416 [ + - + + : 1374 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3417 : : {
3418 [ + - + + ]: 1044 : if (action->commandType != CMD_NOTHING &&
3419 : 522 : view_has_instead_trigger(view, action->commandType, NIL))
3420 [ + - ]: 3 : ereport(ERROR,
3421 : : errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3422 : : errmsg("cannot merge into view \"%s\"",
3423 : : RelationGetRelationName(view)),
3424 : : errdetail("MERGE is not supported for views with INSTEAD OF triggers for some actions but not all."),
3425 : : errhint("To enable merging into the view, either provide a full set of INSTEAD OF triggers or drop the existing INSTEAD OF triggers."));
3426 : : }
3427 : : }
3428 : :
3429 : : /*
3430 : : * If we get here, view_query_is_auto_updatable() has verified that the
3431 : : * view contains a single base relation.
3432 : : */
4845 tgl@sss.pgh.pa.us 3433 [ - + ]: 1654 : Assert(list_length(viewquery->jointree->fromlist) == 1);
3261 3434 : 1654 : rtr = linitial_node(RangeTblRef, viewquery->jointree->fromlist);
3435 : :
4845 3436 : 1654 : base_rt_index = rtr->rtindex;
3437 : 1654 : base_rte = rt_fetch(base_rt_index, viewquery->rtable);
3438 [ - + ]: 1654 : Assert(base_rte->rtekind == RTE_RELATION);
1195 alvherre@alvh.no-ip. 3439 : 1654 : base_perminfo = getRTEPermissionInfo(viewquery->rteperminfos, base_rte);
3440 : :
3441 : : /*
3442 : : * Up to now, the base relation hasn't been touched at all in our query.
3443 : : * We need to acquire lock on it before we try to do anything with it.
3444 : : * (The subsequent recursive call of RewriteQuery will suppose that we
3445 : : * already have the right lock!) Since it will become the query target
3446 : : * relation, RowExclusiveLock is always the right thing.
3447 : : */
4 peter@eisentraut.org 3448 :GNC 1654 : base_rel = relation_open(base_rte->relid, RowExclusiveLock);
3449 : :
3450 : : /*
3451 : : * While we have the relation open, update the RTE's relkind, just in case
3452 : : * it changed since this view was made (cf. AcquireRewriteLocks).
3453 : : */
4845 tgl@sss.pgh.pa.us 3454 :CBC 1654 : base_rte->relkind = base_rel->rd_rel->relkind;
3455 : :
3456 : : /*
3457 : : * If the view query contains any sublink subqueries then we need to also
3458 : : * acquire locks on any relations they refer to. We know that there won't
3459 : : * be any subqueries in the range table or CTEs, so we can skip those, as
3460 : : * in AcquireRewriteLocks.
3461 : : */
3841 sfrost@snowman.net 3462 [ + + ]: 1654 : if (viewquery->hasSubLinks)
3463 : : {
3464 : : acquireLocksOnSubLinks_context context;
3465 : :
3466 : 129 : context.for_execute = true;
3467 : 129 : query_tree_walker(viewquery, acquireLocksOnSubLinks, &context,
3468 : : QTW_IGNORE_RC_SUBQUERIES);
3469 : : }
3470 : :
3471 : : /*
3472 : : * Create a new target RTE describing the base relation, and add it to the
3473 : : * outer query's rangetable. (What's happening in the next few steps is
3474 : : * very much like what the planner would do to "pull up" the view into the
3475 : : * outer query. Perhaps someday we should refactor things enough so that
3476 : : * we can share code with the planner.)
3477 : : *
3478 : : * Be sure to set rellockmode to the correct thing for the target table.
3479 : : * Since we copied the whole viewquery above, we can just scribble on
3480 : : * base_rte instead of copying it.
3481 : : */
2723 tgl@sss.pgh.pa.us 3482 : 1654 : new_rte = base_rte;
3483 : 1654 : new_rte->rellockmode = RowExclusiveLock;
3484 : :
4845 3485 : 1654 : parsetree->rtable = lappend(parsetree->rtable, new_rte);
3486 : 1654 : new_rt_index = list_length(parsetree->rtable);
3487 : :
3488 : : /*
3489 : : * INSERTs never inherit. For UPDATE/DELETE/MERGE, we use the view
3490 : : * query's inheritance flag for the base relation.
3491 : : */
4638 3492 [ + + ]: 1654 : if (parsetree->commandType == CMD_INSERT)
3493 : 597 : new_rte->inh = false;
3494 : :
3495 : : /*
3496 : : * Adjust the view's targetlist Vars to reference the new target RTE, ie
3497 : : * make their varnos be new_rt_index instead of base_rt_index. There can
3498 : : * be no Vars for other rels in the tlist, so this is sufficient to pull
3499 : : * up the tlist expressions for use in the outer query. The tlist will
3500 : : * provide the replacement expressions used by ReplaceVarsFromTargetList
3501 : : * below.
3502 : : */
3737 sfrost@snowman.net 3503 : 1654 : view_targetlist = viewquery->targetList;
3504 : :
4845 tgl@sss.pgh.pa.us 3505 : 1654 : ChangeVarNodes((Node *) view_targetlist,
3506 : : base_rt_index,
3507 : : new_rt_index,
3508 : : 0);
3509 : :
3510 : : /*
3511 : : * If the view has "security_invoker" set, mark the new target relation
3512 : : * for the permissions checks that we want to enforce against the query
3513 : : * caller. Otherwise we want to enforce them against the view owner.
3514 : : *
3515 : : * At the relation level, require the same INSERT/UPDATE/DELETE
3516 : : * permissions that the query caller needs against the view. We drop the
3517 : : * ACL_SELECT bit that is presumably in new_perminfo->requiredPerms
3518 : : * initially.
3519 : : *
3520 : : * Note: the original view's RTEPermissionInfo remains in the query's
3521 : : * rteperminfos so that the executor still performs appropriate
3522 : : * permissions checks for the query caller's use of the view.
3523 : : *
3524 : : * Disregard the perminfo in viewquery->rteperminfos that the base_rte
3525 : : * would currently be pointing at, because we'd like it to point now to a
3526 : : * new one that will be filled below. Must set perminfoindex to 0 to not
3527 : : * trip over the Assert in addRTEPermissionInfo().
3528 : : */
1195 alvherre@alvh.no-ip. 3529 : 1654 : new_rte->perminfoindex = 0;
3530 : 1654 : new_perminfo = addRTEPermissionInfo(&parsetree->rteperminfos, new_rte);
1454 dean.a.rasheed@gmail 3531 [ - + + + : 1654 : if (RelationHasSecurityInvoker(view))
+ + ]
1195 alvherre@alvh.no-ip. 3532 : 243 : new_perminfo->checkAsUser = InvalidOid;
3533 : : else
3534 : 1411 : new_perminfo->checkAsUser = view->rd_rel->relowner;
3535 : 1654 : new_perminfo->requiredPerms = view_perminfo->requiredPerms;
3536 : :
3537 : : /*
3538 : : * Now for the per-column permissions bits.
3539 : : *
3540 : : * Initially, new_perminfo (base_perminfo) contains selectedCols
3541 : : * permission check bits for all base-rel columns referenced by the view,
3542 : : * but since the view is a SELECT query its insertedCols/updatedCols is
3543 : : * empty. We set insertedCols and updatedCols to include all the columns
3544 : : * the outer query is trying to modify, adjusting the column numbers as
3545 : : * needed. But we leave selectedCols as-is, so the view owner must have
3546 : : * read permission for all columns used in the view definition, even if
3547 : : * some of them are not read by the outer query. We could try to limit
3548 : : * selectedCols to only columns used in the transformed query, but that
3549 : : * does not correspond to what happens in ordinary SELECT usage of a view:
3550 : : * all referenced columns must have read permission, even if optimization
3551 : : * finds that some of them can be discarded during query transformation.
3552 : : * The flattening we're doing here is an optional optimization, too. (If
3553 : : * you are unpersuaded and want to change this, note that applying
3554 : : * adjust_view_column_set to view_perminfo->selectedCols is clearly *not*
3555 : : * the right answer, since that neglects base-rel columns used in the
3556 : : * view's WHERE quals.)
3557 : : *
3558 : : * This step needs the modified view targetlist, so we have to do things
3559 : : * in this order.
3560 : : */
3561 [ + - - + ]: 1654 : Assert(bms_is_empty(new_perminfo->insertedCols) &&
3562 : : bms_is_empty(new_perminfo->updatedCols));
3563 : :
3564 : 1654 : new_perminfo->selectedCols = base_perminfo->selectedCols;
3565 : :
3566 : 1654 : new_perminfo->insertedCols =
3567 : 1654 : adjust_view_column_set(view_perminfo->insertedCols, view_targetlist);
3568 : :
3569 : 1654 : new_perminfo->updatedCols =
3570 : 1654 : adjust_view_column_set(view_perminfo->updatedCols, view_targetlist);
3571 : :
3572 : : /*
3573 : : * Move any security barrier quals from the view RTE onto the new target
3574 : : * RTE. Any such quals should now apply to the new target RTE and will
3575 : : * not reference the original view RTE in the rewritten query.
3576 : : */
4355 sfrost@snowman.net 3577 : 1654 : new_rte->securityQuals = view_rte->securityQuals;
3578 : 1654 : view_rte->securityQuals = NIL;
3579 : :
3580 : : /*
3581 : : * Now update all Vars in the outer query that reference the view to
3582 : : * reference the appropriate column of the base relation instead.
3583 : : */
3584 : : parsetree = (Query *)
4845 tgl@sss.pgh.pa.us 3585 : 1654 : ReplaceVarsFromTargetList((Node *) parsetree,
3586 : : parsetree->resultRelation,
3587 : : 0,
3588 : : view_rte,
3589 : : view_targetlist,
3590 : : new_rt_index,
3591 : : REPLACEVARS_REPORT_ERROR,
3592 : : 0,
3593 : : NULL);
3594 : :
3595 : : /*
3596 : : * Update all other RTI references in the query that point to the view
3597 : : * (for example, parsetree->resultRelation itself) to point to the new
3598 : : * base relation instead. Vars will not be affected since none of them
3599 : : * reference parsetree->resultRelation any longer.
3600 : : */
3601 : 1654 : ChangeVarNodes((Node *) parsetree,
3602 : : parsetree->resultRelation,
3603 : : new_rt_index,
3604 : : 0);
3605 [ - + ]: 1654 : Assert(parsetree->resultRelation == new_rt_index);
3606 : :
3607 : : /*
3608 : : * For INSERT/UPDATE we must also update resnos in the targetlist to refer
3609 : : * to columns of the base relation, since those indicate the target
3610 : : * columns to be affected. Similarly, for MERGE we must update the resnos
3611 : : * in the merge action targetlists of any INSERT/UPDATE actions.
3612 : : *
3613 : : * Note that this destroys the resno ordering of the targetlists, but that
3614 : : * will be fixed when we recurse through RewriteQuery, which will invoke
3615 : : * rewriteTargetListIU again on the updated targetlists.
3616 : : */
3617 [ + + ]: 1654 : if (parsetree->commandType != CMD_DELETE)
3618 : : {
3619 [ + + + + : 3106 : foreach(lc, parsetree->targetList)
+ + ]
3620 : : {
3621 : 1602 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3622 : : TargetEntry *view_tle;
3623 : :
3624 [ - + ]: 1602 : if (tle->resjunk)
4845 tgl@sss.pgh.pa.us 3625 :UBC 0 : continue;
3626 : :
4845 tgl@sss.pgh.pa.us 3627 :CBC 1602 : view_tle = get_tle_by_resno(view_targetlist, tle->resno);
3628 [ + - + - : 1602 : if (view_tle != NULL && !view_tle->resjunk && IsA(view_tle->expr, Var))
+ - ]
3629 : 1602 : tle->resno = ((Var *) view_tle->expr)->varattno;
3630 : : else
4845 tgl@sss.pgh.pa.us 3631 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3632 : : tle->resno);
3633 : : }
3634 : :
745 dean.a.rasheed@gmail 3635 [ + + + + :CBC 3527 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3636 : : {
3637 [ + + ]: 519 : if (action->commandType == CMD_INSERT ||
3638 [ + + ]: 420 : action->commandType == CMD_UPDATE)
3639 : : {
3640 [ + - + + : 1428 : foreach_node(TargetEntry, tle, action->targetList)
+ + ]
3641 : : {
3642 : : TargetEntry *view_tle;
3643 : :
3644 [ - + ]: 546 : if (tle->resjunk)
745 dean.a.rasheed@gmail 3645 :UBC 0 : continue;
3646 : :
745 dean.a.rasheed@gmail 3647 :CBC 546 : view_tle = get_tle_by_resno(view_targetlist, tle->resno);
3648 [ + - + - : 546 : if (view_tle != NULL && !view_tle->resjunk && IsA(view_tle->expr, Var))
+ - ]
3649 : 546 : tle->resno = ((Var *) view_tle->expr)->varattno;
3650 : : else
745 dean.a.rasheed@gmail 3651 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3652 : : tle->resno);
3653 : : }
3654 : : }
3655 : : }
3656 : : }
3657 : :
3658 : : /*
3659 : : * For INSERT .. ON CONFLICT .. DO SELECT/UPDATE, we must also update
3660 : : * assorted stuff in the onConflict data structure.
3661 : : */
2780 tgl@sss.pgh.pa.us 3662 [ + + ]:CBC 1654 : if (parsetree->onConflict &&
31 dean.a.rasheed@gmail 3663 [ + + ]:GNC 123 : (parsetree->onConflict->action == ONCONFLICT_UPDATE ||
3664 [ + + ]: 48 : parsetree->onConflict->action == ONCONFLICT_SELECT))
3665 : : {
3666 : : Index old_exclRelIndex,
3667 : : new_exclRelIndex;
3668 : : ParseNamespaceItem *new_exclNSItem;
3669 : : RangeTblEntry *new_exclRte;
3670 : : List *tmp_tlist;
3671 : :
3672 : : /*
3673 : : * For ON CONFLICT DO UPDATE, update the resnos in the auxiliary
3674 : : * UPDATE targetlist to refer to columns of the base relation.
3675 : : */
2780 tgl@sss.pgh.pa.us 3676 [ + + + + :CBC 186 : foreach(lc, parsetree->onConflict->onConflictSet)
+ + ]
3677 : : {
3678 : 75 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3679 : : TargetEntry *view_tle;
3680 : :
3681 [ - + ]: 75 : if (tle->resjunk)
2780 tgl@sss.pgh.pa.us 3682 :UBC 0 : continue;
3683 : :
2780 tgl@sss.pgh.pa.us 3684 :CBC 75 : view_tle = get_tle_by_resno(view_targetlist, tle->resno);
3685 [ + - + - : 75 : if (view_tle != NULL && !view_tle->resjunk && IsA(view_tle->expr, Var))
+ - ]
3686 : 75 : tle->resno = ((Var *) view_tle->expr)->varattno;
3687 : : else
2780 tgl@sss.pgh.pa.us 3688 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3689 : : tle->resno);
3690 : : }
3691 : :
3692 : : /*
3693 : : * Create a new RTE for the EXCLUDED pseudo-relation, using the
3694 : : * query's new base rel (which may well have a different column list
3695 : : * from the view, hence we need a new column alias list). This should
3696 : : * match transformOnConflictClause. In particular, note that the
3697 : : * relkind is set to composite to signal that we're not dealing with
3698 : : * an actual relation.
3699 : : */
2780 tgl@sss.pgh.pa.us 3700 :CBC 111 : old_exclRelIndex = parsetree->onConflict->exclRelIndex;
3701 : :
2264 3702 : 111 : new_exclNSItem = addRangeTableEntryForRelation(make_parsestate(NULL),
3703 : : base_rel,
3704 : : RowExclusiveLock,
3705 : : makeAlias("excluded", NIL),
3706 : : false, false);
3707 : 111 : new_exclRte = new_exclNSItem->p_rte;
2780 3708 : 111 : new_exclRte->relkind = RELKIND_COMPOSITE_TYPE;
3709 : : /* Ignore the RTEPermissionInfo that would've been added. */
1195 alvherre@alvh.no-ip. 3710 : 111 : new_exclRte->perminfoindex = 0;
3711 : :
2780 tgl@sss.pgh.pa.us 3712 : 111 : parsetree->rtable = lappend(parsetree->rtable, new_exclRte);
3713 : 222 : new_exclRelIndex = parsetree->onConflict->exclRelIndex =
3714 : 111 : list_length(parsetree->rtable);
3715 : :
3716 : : /*
3717 : : * Replace the targetlist for the EXCLUDED pseudo-relation with a new
3718 : : * one, representing the columns from the new base relation.
3719 : : */
3720 : 222 : parsetree->onConflict->exclRelTlist =
3721 : 111 : BuildOnConflictExcludedTargetlist(base_rel, new_exclRelIndex);
3722 : :
3723 : : /*
3724 : : * Update all Vars in the ON CONFLICT clause that refer to the old
3725 : : * EXCLUDED pseudo-relation. We want to use the column mappings
3726 : : * defined in the view targetlist, but we need the outputs to refer to
3727 : : * the new EXCLUDED pseudo-relation rather than the new target RTE.
3728 : : * Also notice that "EXCLUDED.*" will be expanded using the view's
3729 : : * rowtype, which seems correct.
3730 : : */
3731 : 111 : tmp_tlist = copyObject(view_targetlist);
3732 : :
3733 : 111 : ChangeVarNodes((Node *) tmp_tlist, new_rt_index,
3734 : : new_exclRelIndex, 0);
3735 : :
3736 : 111 : parsetree->onConflict = (OnConflictExpr *)
3737 : 111 : ReplaceVarsFromTargetList((Node *) parsetree->onConflict,
3738 : : old_exclRelIndex,
3739 : : 0,
3740 : : view_rte,
3741 : : tmp_tlist,
3742 : : new_rt_index,
3743 : : REPLACEVARS_REPORT_ERROR,
3744 : : 0,
3745 : : &parsetree->hasSubLinks);
3746 : : }
3747 : :
3748 : : /*
3749 : : * For UPDATE/DELETE/MERGE, pull up any WHERE quals from the view. We
3750 : : * know that any Vars in the quals must reference the one base relation,
3751 : : * so we need only adjust their varnos to reference the new target (just
3752 : : * the same as we did with the view targetlist).
3753 : : *
3754 : : * If it's a security-barrier view, its WHERE quals must be applied before
3755 : : * quals from the outer query, so we attach them to the RTE as security
3756 : : * barrier quals rather than adding them to the main WHERE clause.
3757 : : *
3758 : : * For INSERT, the view's quals can be ignored in the main query.
3759 : : */
4845 3760 [ + + ]: 1654 : if (parsetree->commandType != CMD_INSERT &&
3761 [ + + ]: 1057 : viewquery->jointree->quals != NULL)
3762 : : {
3737 sfrost@snowman.net 3763 : 379 : Node *viewqual = (Node *) viewquery->jointree->quals;
3764 : :
3765 : : /*
3766 : : * Even though we copied viewquery already at the top of this
3767 : : * function, we must duplicate the viewqual again here, because we may
3768 : : * need to use the quals again below for a WithCheckOption clause.
3769 : : */
3729 tgl@sss.pgh.pa.us 3770 : 379 : viewqual = copyObject(viewqual);
3771 : :
4845 3772 : 379 : ChangeVarNodes(viewqual, base_rt_index, new_rt_index, 0);
3773 : :
4355 sfrost@snowman.net 3774 [ - + + + : 379 : if (RelationIsSecurityView(view))
+ + ]
3775 : : {
3776 : : /*
3777 : : * The view's quals go in front of existing barrier quals: those
3778 : : * would have come from an outer level of security-barrier view,
3779 : : * and so must get evaluated later.
3780 : : *
3781 : : * Note: the parsetree has been mutated, so the new_rte pointer is
3782 : : * stale and needs to be re-computed.
3783 : : */
3784 : 117 : new_rte = rt_fetch(new_rt_index, parsetree->rtable);
3785 : 117 : new_rte->securityQuals = lcons(viewqual, new_rte->securityQuals);
3786 : :
3787 : : /*
3788 : : * Do not set parsetree->hasRowSecurity, because these aren't RLS
3789 : : * conditions (they aren't affected by enabling/disabling RLS).
3790 : : */
3791 : :
3792 : : /*
3793 : : * Make sure that the query is marked correctly if the added qual
3794 : : * has sublinks.
3795 : : */
3796 [ + + ]: 117 : if (!parsetree->hasSubLinks)
3797 : 105 : parsetree->hasSubLinks = checkExprHasSubLink(viewqual);
3798 : : }
3799 : : else
103 peter@eisentraut.org 3800 :GNC 262 : AddQual(parsetree, viewqual);
3801 : : }
3802 : :
3803 : : /*
3804 : : * For INSERT/UPDATE (or MERGE containing INSERT/UPDATE), if the view has
3805 : : * the WITH CHECK OPTION, or any parent view specified WITH CASCADED CHECK
3806 : : * OPTION, add the quals from the view to the query's withCheckOptions
3807 : : * list.
3808 : : */
745 dean.a.rasheed@gmail 3809 [ + + ]:CBC 1654 : if (insert_or_update)
3810 : : {
4623 sfrost@snowman.net 3811 [ - + + + : 1462 : bool has_wco = RelationHasCheckOption(view);
+ + ]
3812 [ - + + + : 1462 : bool cascaded = RelationHasCascadedCheckOption(view);
+ + ]
3813 : :
3814 : : /*
3815 : : * If the parent view has a cascaded check option, treat this view as
3816 : : * if it also had a cascaded check option.
3817 : : *
3818 : : * New WithCheckOptions are added to the start of the list, so if
3819 : : * there is a cascaded check option, it will be the first item in the
3820 : : * list.
3821 : : */
3822 [ + + ]: 1462 : if (parsetree->withCheckOptions != NIL)
3823 : : {
3824 : 57 : WithCheckOption *parent_wco =
1031 tgl@sss.pgh.pa.us 3825 : 57 : (WithCheckOption *) linitial(parsetree->withCheckOptions);
3826 : :
4623 sfrost@snowman.net 3827 [ + + ]: 57 : if (parent_wco->cascaded)
3828 : : {
3829 : 45 : has_wco = true;
3830 : 45 : cascaded = true;
3831 : : }
3832 : : }
3833 : :
3834 : : /*
3835 : : * Add the new WithCheckOption to the start of the list, so that
3836 : : * checks on inner views are run before checks on outer views, as
3837 : : * required by the SQL standard.
3838 : : *
3839 : : * If the new check is CASCADED, we need to add it even if this view
3840 : : * has no quals, since there may be quals on child views. A LOCAL
3841 : : * check can be omitted if this view has no quals.
3842 : : */
3843 [ + + + + : 1462 : if (has_wco && (cascaded || viewquery->jointree->quals != NULL))
+ - ]
3844 : : {
3845 : : WithCheckOption *wco;
3846 : :
3847 : 328 : wco = makeNode(WithCheckOption);
3978 3848 : 328 : wco->kind = WCO_VIEW_CHECK;
3849 : 328 : wco->relname = pstrdup(RelationGetRelationName(view));
3834 3850 : 328 : wco->polname = NULL;
4623 3851 : 328 : wco->qual = NULL;
3852 : 328 : wco->cascaded = cascaded;
3853 : :
3854 : 328 : parsetree->withCheckOptions = lcons(wco,
3855 : : parsetree->withCheckOptions);
3856 : :
3857 [ + + ]: 328 : if (viewquery->jointree->quals != NULL)
3858 : : {
3737 3859 : 298 : wco->qual = (Node *) viewquery->jointree->quals;
4623 3860 : 298 : ChangeVarNodes(wco->qual, base_rt_index, new_rt_index, 0);
3861 : :
3862 : : /*
3863 : : * For INSERT, make sure that the query is marked correctly if
3864 : : * the added qual has sublinks. This can be skipped for
3865 : : * UPDATE/MERGE, since the same qual will have already been
3866 : : * added above, and the check will already have been done.
3867 : : */
3868 [ + + ]: 298 : if (!parsetree->hasSubLinks &&
745 dean.a.rasheed@gmail 3869 [ + + ]: 250 : parsetree->commandType == CMD_INSERT)
4623 sfrost@snowman.net 3870 : 156 : parsetree->hasSubLinks = checkExprHasSubLink(wco->qual);
3871 : : }
3872 : : }
3873 : : }
3874 : :
2610 andres@anarazel.de 3875 : 1654 : table_close(base_rel, NoLock);
3876 : :
4845 tgl@sss.pgh.pa.us 3877 : 1654 : return parsetree;
3878 : : }
3879 : :
3880 : :
3881 : : /*
3882 : : * RewriteQuery -
3883 : : * rewrites the query and apply the rules again on the queries rewritten
3884 : : *
3885 : : * rewrite_events is a list of open query-rewrite actions, so we can detect
3886 : : * infinite recursion.
3887 : : *
3888 : : * orig_rt_length is the length of the originating query's rtable, for product
3889 : : * queries created by fireRules(), and 0 otherwise. This is used to skip any
3890 : : * already-processed VALUES RTEs from the original query.
3891 : : *
3892 : : * num_ctes_processed is the number of CTEs at the end of the query's cteList
3893 : : * that have already been rewritten, and must not be rewritten again.
3894 : : */
3895 : : static List *
106 dean.a.rasheed@gmail 3896 : 239567 : RewriteQuery(Query *parsetree, List *rewrite_events, int orig_rt_length,
3897 : : int num_ctes_processed)
3898 : : {
8419 tgl@sss.pgh.pa.us 3899 : 239567 : CmdType event = parsetree->commandType;
3900 : 239567 : bool instead = false;
7134 3901 : 239567 : bool returning = false;
3964 andres@anarazel.de 3902 : 239567 : bool updatableview = false;
8419 tgl@sss.pgh.pa.us 3903 : 239567 : Query *qual_product = NULL;
3904 : 239567 : List *rewritten = NIL;
3905 : : ListCell *lc1;
3906 : :
3907 : : /*
3908 : : * First, recursively process any insert/update/delete/merge statements in
3909 : : * WITH clauses. (We have to do this first because the WITH clauses may
3910 : : * get copied into rule actions below.)
3911 : : *
3912 : : * Any new WITH clauses from rule actions are processed when we recurse
3913 : : * into product queries below. However, when recursing, we must take care
3914 : : * to avoid rewriting a CTE query more than once (because expanding
3915 : : * generated columns in the targetlist more than once would fail). Since
3916 : : * new CTEs from product queries are added to the start of the list (see
3917 : : * rewriteRuleAction), we just skip the last num_ctes_processed items.
3918 : : */
5395 3919 [ + + + + : 241563 : foreach(lc1, parsetree->cteList)
+ + ]
3920 : : {
3261 3921 : 2032 : CommonTableExpr *cte = lfirst_node(CommonTableExpr, lc1);
3309 peter_e@gmx.net 3922 : 2032 : Query *ctequery = castNode(Query, cte->ctequery);
106 dean.a.rasheed@gmail 3923 : 2032 : int i = foreach_current_index(lc1);
3924 : : List *newstuff;
3925 : :
3926 : : /* Skip already-processed CTEs at the end of the list */
3927 [ + + ]: 2032 : if (i >= list_length(parsetree->cteList) - num_ctes_processed)
3928 : 21 : break;
3929 : :
5395 tgl@sss.pgh.pa.us 3930 [ + + ]: 2011 : if (ctequery->commandType == CMD_SELECT)
3931 : 1822 : continue;
3932 : :
106 dean.a.rasheed@gmail 3933 : 189 : newstuff = RewriteQuery(ctequery, rewrite_events, 0, 0);
3934 : :
3935 : : /*
3936 : : * Currently we can only handle unconditional, single-statement DO
3937 : : * INSTEAD rules correctly; we have to get exactly one non-utility
3938 : : * Query out of the rewrite operation to stuff back into the CTE node.
3939 : : */
5395 tgl@sss.pgh.pa.us 3940 [ + + ]: 189 : if (list_length(newstuff) == 1)
3941 : : {
3942 : : /* Must check it's not a utility command */
3261 3943 : 177 : ctequery = linitial_node(Query, newstuff);
1710 3944 [ + - ]: 177 : if (!(ctequery->commandType == CMD_SELECT ||
3945 [ + + ]: 177 : ctequery->commandType == CMD_UPDATE ||
3946 [ + + ]: 130 : ctequery->commandType == CMD_INSERT ||
728 dean.a.rasheed@gmail 3947 [ + + ]: 43 : ctequery->commandType == CMD_DELETE ||
3948 [ + + ]: 17 : ctequery->commandType == CMD_MERGE))
3949 : : {
3950 : : /*
3951 : : * Currently it could only be NOTIFY; this error message will
3952 : : * need work if we ever allow other utility commands in rules.
3953 : : */
1710 tgl@sss.pgh.pa.us 3954 [ + - ]: 3 : ereport(ERROR,
3955 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3956 : : errmsg("DO INSTEAD NOTIFY rules are not supported for data-modifying statements in WITH")));
3957 : : }
3958 : : /* WITH queries should never be canSetTag */
5395 3959 [ - + ]: 174 : Assert(!ctequery->canSetTag);
3960 : : /* Push the single Query back into the CTE node */
3961 : 174 : cte->ctequery = (Node *) ctequery;
3962 : : }
3963 [ + + ]: 12 : else if (newstuff == NIL)
3964 : : {
3965 [ + - ]: 3 : ereport(ERROR,
3966 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3967 : : errmsg("DO INSTEAD NOTHING rules are not supported for data-modifying statements in WITH")));
3968 : : }
3969 : : else
3970 : : {
3971 : : ListCell *lc2;
3972 : :
3973 : : /* examine queries to determine which error message to issue */
3974 [ + - + + : 21 : foreach(lc2, newstuff)
+ + ]
3975 : : {
3976 : 18 : Query *q = (Query *) lfirst(lc2);
3977 : :
3978 [ + + ]: 18 : if (q->querySource == QSRC_QUAL_INSTEAD_RULE)
3979 [ + - ]: 3 : ereport(ERROR,
3980 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3981 : : errmsg("conditional DO INSTEAD rules are not supported for data-modifying statements in WITH")));
3982 [ + + ]: 15 : if (q->querySource == QSRC_NON_INSTEAD_RULE)
3983 [ + - ]: 3 : ereport(ERROR,
3984 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3985 : : errmsg("DO ALSO rules are not supported for data-modifying statements in WITH")));
3986 : : }
3987 : :
3988 [ + - ]: 3 : ereport(ERROR,
3989 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3990 : : errmsg("multi-statement DO INSTEAD rules are not supported for data-modifying statements in WITH")));
3991 : : }
3992 : : }
106 dean.a.rasheed@gmail 3993 : 239552 : num_ctes_processed = list_length(parsetree->cteList);
3994 : :
3995 : : /*
3996 : : * If the statement is an insert, update, delete, or merge, adjust its
3997 : : * targetlist as needed, and then fire INSERT/UPDATE/DELETE rules on it.
3998 : : *
3999 : : * SELECT rules are handled later when we have all the queries that should
4000 : : * get executed. Also, utilities aren't rewritten at all (do we still
4001 : : * need that check?)
4002 : : */
8419 tgl@sss.pgh.pa.us 4003 [ + + + + ]: 239552 : if (event != CMD_SELECT && event != CMD_UTILITY)
4004 : : {
4005 : : int result_relation;
4006 : : RangeTblEntry *rt_entry;
4007 : : Relation rt_entry_relation;
4008 : : List *locks;
4009 : : int product_orig_rt_length;
4010 : : List *product_queries;
3964 andres@anarazel.de 4011 : 45584 : bool hasUpdate = false;
2580 dean.a.rasheed@gmail 4012 : 45584 : int values_rte_index = 0;
4013 : 45584 : bool defaults_remaining = false;
4014 : :
8419 tgl@sss.pgh.pa.us 4015 : 45584 : result_relation = parsetree->resultRelation;
4016 [ - + ]: 45584 : Assert(result_relation != 0);
4017 : 45584 : rt_entry = rt_fetch(result_relation, parsetree->rtable);
4018 [ - + ]: 45584 : Assert(rt_entry->rtekind == RTE_RELATION);
4019 : :
4020 : : /*
4021 : : * We can use NoLock here since either the parser or
4022 : : * AcquireRewriteLocks should have locked the rel already.
4023 : : */
4 peter@eisentraut.org 4024 :GNC 45584 : rt_entry_relation = relation_open(rt_entry->relid, NoLock);
4025 : :
4026 : : /*
4027 : : * Rewrite the targetlist as needed for the command type.
4028 : : */
5635 tgl@sss.pgh.pa.us 4029 [ + + ]:CBC 45584 : if (event == CMD_INSERT)
4030 : : {
4031 : : ListCell *lc2;
7165 mail@joeconway.com 4032 : 33887 : RangeTblEntry *values_rte = NULL;
4033 : :
4034 : : /*
4035 : : * Test if it's a multi-row INSERT ... VALUES (...), (...), ... by
4036 : : * looking for a VALUES RTE in the fromlist. For product queries,
4037 : : * we must ignore any already-processed VALUES RTEs from the
4038 : : * original query. These appear at the start of the rangetable.
4039 : : */
1198 dean.a.rasheed@gmail 4040 [ + + + + : 40354 : foreach(lc2, parsetree->jointree->fromlist)
+ + ]
4041 : : {
4042 : 6467 : RangeTblRef *rtr = (RangeTblRef *) lfirst(lc2);
4043 : :
4044 [ + - + + ]: 6467 : if (IsA(rtr, RangeTblRef) && rtr->rtindex > orig_rt_length)
4045 : : {
7165 mail@joeconway.com 4046 : 6305 : RangeTblEntry *rte = rt_fetch(rtr->rtindex,
4047 : : parsetree->rtable);
4048 : :
4049 [ + + ]: 6305 : if (rte->rtekind == RTE_VALUES)
4050 : : {
4051 : : /* should not find more than one VALUES RTE */
1198 dean.a.rasheed@gmail 4052 [ - + ]: 2604 : if (values_rte != NULL)
1198 dean.a.rasheed@gmail 4053 [ # # ]:UBC 0 : elog(ERROR, "more than one VALUES RTE found");
4054 : :
7165 mail@joeconway.com 4055 :CBC 2604 : values_rte = rte;
2580 dean.a.rasheed@gmail 4056 : 2604 : values_rte_index = rtr->rtindex;
4057 : : }
4058 : : }
4059 : : }
4060 : :
7165 mail@joeconway.com 4061 [ + + ]: 33887 : if (values_rte)
4062 : : {
1939 tgl@sss.pgh.pa.us 4063 : 2604 : Bitmapset *unused_values_attrnos = NULL;
4064 : :
4065 : : /* Process the main targetlist ... */
3964 andres@anarazel.de 4066 : 2604 : parsetree->targetList = rewriteTargetListIU(parsetree->targetList,
4067 : : parsetree->commandType,
4068 : : parsetree->override,
4069 : : rt_entry_relation,
4070 : : values_rte,
4071 : : values_rte_index,
4072 : : &unused_values_attrnos);
4073 : : /* ... and the VALUES expression lists */
2569 dean.a.rasheed@gmail 4074 [ + + ]: 2553 : if (!rewriteValuesRTE(parsetree, values_rte, values_rte_index,
4075 : : rt_entry_relation,
4076 : : unused_values_attrnos))
2580 4077 : 39 : defaults_remaining = true;
4078 : : }
4079 : : else
4080 : : {
4081 : : /* Process just the main targetlist */
3964 andres@anarazel.de 4082 : 31244 : parsetree->targetList =
4083 : 31283 : rewriteTargetListIU(parsetree->targetList,
4084 : : parsetree->commandType,
4085 : : parsetree->override,
4086 : : rt_entry_relation,
4087 : : NULL, 0, NULL);
4088 : : }
4089 : :
4090 [ + + ]: 33797 : if (parsetree->onConflict &&
4091 [ + + ]: 1296 : parsetree->onConflict->action == ONCONFLICT_UPDATE)
4092 : : {
4093 : 766 : parsetree->onConflict->onConflictSet =
4094 : 766 : rewriteTargetListIU(parsetree->onConflict->onConflictSet,
4095 : : CMD_UPDATE,
4096 : : parsetree->override,
4097 : : rt_entry_relation,
4098 : : NULL, 0, NULL);
4099 : : }
4100 : : }
5635 tgl@sss.pgh.pa.us 4101 [ + + ]: 11697 : else if (event == CMD_UPDATE)
4102 : : {
1448 alvherre@alvh.no-ip. 4103 [ - + ]: 7813 : Assert(parsetree->override == OVERRIDING_NOT_SET);
3964 andres@anarazel.de 4104 : 7798 : parsetree->targetList =
4105 : 7813 : rewriteTargetListIU(parsetree->targetList,
4106 : : parsetree->commandType,
4107 : : parsetree->override,
4108 : : rt_entry_relation,
4109 : : NULL, 0, NULL);
4110 : : }
1448 alvherre@alvh.no-ip. 4111 [ + + ]: 3884 : else if (event == CMD_MERGE)
4112 : : {
4113 [ - + ]: 1451 : Assert(parsetree->override == OVERRIDING_NOT_SET);
4114 : :
4115 : : /*
4116 : : * Rewrite each action targetlist separately
4117 : : */
4118 [ + - + + : 3551 : foreach(lc1, parsetree->mergeActionList)
+ + ]
4119 : : {
4120 : 2103 : MergeAction *action = (MergeAction *) lfirst(lc1);
4121 : :
4122 [ + + - ]: 2103 : switch (action->commandType)
4123 : : {
4124 : 376 : case CMD_NOTHING:
4125 : : case CMD_DELETE: /* Nothing to do here */
4126 : 376 : break;
4127 : 1727 : case CMD_UPDATE:
4128 : : case CMD_INSERT:
4129 : :
4130 : : /*
4131 : : * MERGE actions do not permit multi-row INSERTs, so
4132 : : * there is no VALUES RTE to deal with here.
4133 : : */
4134 : 1724 : action->targetList =
4135 : 1727 : rewriteTargetListIU(action->targetList,
4136 : : action->commandType,
4137 : : action->override,
4138 : : rt_entry_relation,
4139 : : NULL, 0, NULL);
4140 : 1724 : break;
1448 alvherre@alvh.no-ip. 4141 :UBC 0 : default:
4142 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d", action->commandType);
4143 : : break;
4144 : : }
4145 : : }
4146 : : }
5635 tgl@sss.pgh.pa.us 4147 [ - + ]:CBC 2433 : else if (event == CMD_DELETE)
4148 : : {
4149 : : /* Nothing to do here */
4150 : : }
4151 : : else
5635 tgl@sss.pgh.pa.us 4152 [ # # ]:UBC 0 : elog(ERROR, "unrecognized commandType: %d", (int) event);
4153 : :
4154 : : /*
4155 : : * Collect and apply the appropriate rules.
4156 : : */
745 dean.a.rasheed@gmail 4157 :CBC 45476 : locks = matchLocks(event, rt_entry_relation,
4158 : : result_relation, parsetree, &hasUpdate);
4159 : :
1198 4160 : 45467 : product_orig_rt_length = list_length(parsetree->rtable);
2894 simon@2ndQuadrant.co 4161 : 45467 : product_queries = fireRules(parsetree,
4162 : : result_relation,
4163 : : event,
4164 : : locks,
4165 : : &instead,
4166 : : &returning,
4167 : : &qual_product);
4168 : :
4169 : : /*
4170 : : * If we have a VALUES RTE with any remaining untouched DEFAULT items,
4171 : : * and we got any product queries, finalize the VALUES RTE for each
4172 : : * product query (replacing the remaining DEFAULT items with NULLs).
4173 : : * We don't do this for the original query, because we know that it
4174 : : * must be an auto-insert on a view, and so should use the base
4175 : : * relation's defaults for any remaining DEFAULT items.
4176 : : */
2580 dean.a.rasheed@gmail 4177 [ + + + + ]: 45461 : if (defaults_remaining && product_queries != NIL)
4178 : : {
4179 : : ListCell *n;
4180 : :
4181 : : /*
4182 : : * Each product query has its own copy of the VALUES RTE at the
4183 : : * same index in the rangetable, so we must finalize each one.
4184 : : *
4185 : : * Note that if the product query is an INSERT ... SELECT, then
4186 : : * the VALUES RTE will be at the same index in the SELECT part of
4187 : : * the product query rather than the top-level product query
4188 : : * itself.
4189 : : */
4190 [ + - + + : 24 : foreach(n, product_queries)
+ + ]
4191 : : {
4192 : 12 : Query *pt = (Query *) lfirst(n);
4193 : : RangeTblEntry *values_rte;
4194 : :
1116 4195 [ + - ]: 12 : if (pt->commandType == CMD_INSERT &&
4196 [ + - + - : 24 : pt->jointree && IsA(pt->jointree, FromExpr) &&
+ - ]
4197 : 12 : list_length(pt->jointree->fromlist) == 1)
4198 : : {
4199 : 12 : Node *jtnode = (Node *) linitial(pt->jointree->fromlist);
4200 : :
4201 [ + - ]: 12 : if (IsA(jtnode, RangeTblRef))
4202 : : {
4203 : 12 : int rtindex = ((RangeTblRef *) jtnode)->rtindex;
4204 : 12 : RangeTblEntry *src_rte = rt_fetch(rtindex, pt->rtable);
4205 : :
4206 [ + + ]: 12 : if (src_rte->rtekind == RTE_SUBQUERY &&
4207 [ + - ]: 3 : src_rte->subquery &&
4208 [ + - ]: 3 : IsA(src_rte->subquery, Query) &&
4209 [ + - ]: 3 : src_rte->subquery->commandType == CMD_SELECT)
4210 : 3 : pt = src_rte->subquery;
4211 : : }
4212 : : }
4213 : :
4214 : 12 : values_rte = rt_fetch(values_rte_index, pt->rtable);
4215 [ - + ]: 12 : if (values_rte->rtekind != RTE_VALUES)
1116 dean.a.rasheed@gmail 4216 [ # # ]:UBC 0 : elog(ERROR, "failed to find VALUES RTE in product query");
4217 : :
1251 tgl@sss.pgh.pa.us 4218 :CBC 12 : rewriteValuesRTEToNulls(pt, values_rte);
4219 : : }
4220 : : }
4221 : :
4222 : : /*
4223 : : * If there was no unqualified INSTEAD rule, and the target relation
4224 : : * is a view without any INSTEAD OF triggers, see if the view can be
4225 : : * automatically updated. If so, we perform the necessary query
4226 : : * transformation here and add the resulting query to the
4227 : : * product_queries list, so that it gets recursively rewritten if
4228 : : * necessary. For MERGE, the view must be automatically updatable if
4229 : : * any of the merge actions lack a corresponding INSTEAD OF trigger.
4230 : : *
4231 : : * If the view cannot be automatically updated, we throw an error here
4232 : : * which is OK since the query would fail at runtime anyway. Throwing
4233 : : * the error here is preferable to the executor check since we have
4234 : : * more detailed information available about why the view isn't
4235 : : * updatable.
4236 : : */
2252 dean.a.rasheed@gmail 4237 [ + + ]: 45461 : if (!instead &&
4845 tgl@sss.pgh.pa.us 4238 [ + + ]: 45101 : rt_entry_relation->rd_rel->relkind == RELKIND_VIEW &&
745 dean.a.rasheed@gmail 4239 [ + + ]: 2002 : !view_has_instead_trigger(rt_entry_relation, event,
4240 : : parsetree->mergeActionList))
4241 : : {
4242 : : /*
4243 : : * If there were any qualified INSTEAD rules, don't allow the view
4244 : : * to be automatically updated (an unqualified INSTEAD rule or
4245 : : * INSTEAD OF trigger is required).
4246 : : */
2252 4247 [ + + ]: 1798 : if (qual_product != NULL)
745 4248 : 9 : error_view_not_updatable(rt_entry_relation,
4249 : : parsetree->commandType,
4250 : : parsetree->mergeActionList,
4251 : : gettext_noop("Views with conditional DO INSTEAD rules are not automatically updatable."));
4252 : :
4253 : : /*
4254 : : * Attempt to rewrite the query to automatically update the view.
4255 : : * This throws an error if the view can't be automatically
4256 : : * updated.
4257 : : */
4845 tgl@sss.pgh.pa.us 4258 : 1789 : parsetree = rewriteTargetView(parsetree, rt_entry_relation);
4259 : :
4260 : : /*
4261 : : * At this point product_queries contains any DO ALSO rule
4262 : : * actions. Add the rewritten query before or after those. This
4263 : : * must match the handling the original query would have gotten
4264 : : * below, if we allowed it to be included again.
4265 : : */
4266 [ + + ]: 1654 : if (parsetree->commandType == CMD_INSERT)
4267 : 597 : product_queries = lcons(parsetree, product_queries);
4268 : : else
4269 : 1057 : product_queries = lappend(product_queries, parsetree);
4270 : :
4271 : : /*
4272 : : * Set the "instead" flag, as if there had been an unqualified
4273 : : * INSTEAD, to prevent the original query from being included a
4274 : : * second time below. The transformation will have rewritten any
4275 : : * RETURNING list, so we can also set "returning" to forestall
4276 : : * throwing an error below.
4277 : : */
4278 : 1654 : instead = true;
4279 : 1654 : returning = true;
3964 andres@anarazel.de 4280 : 1654 : updatableview = true;
4281 : : }
4282 : :
4283 : : /*
4284 : : * If we got any product queries, recursively rewrite them --- but
4285 : : * first check for recursion!
4286 : : */
4673 bruce@momjian.us 4287 [ + + ]: 45317 : if (product_queries != NIL)
4288 : : {
4289 : : ListCell *n;
4290 : : rewrite_event *rev;
4291 : :
4292 [ + + + + : 2713 : foreach(n, rewrite_events)
+ + ]
4293 : : {
4294 : 483 : rev = (rewrite_event *) lfirst(n);
4295 [ - + ]: 483 : if (rev->relation == RelationGetRelid(rt_entry_relation) &&
4673 bruce@momjian.us 4296 [ # # ]:UBC 0 : rev->event == event)
4297 [ # # ]: 0 : ereport(ERROR,
4298 : : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
4299 : : errmsg("infinite recursion detected in rules for relation \"%s\"",
4300 : : RelationGetRelationName(rt_entry_relation))));
4301 : : }
4302 : :
95 michael@paquier.xyz 4303 :GNC 2230 : rev = palloc_object(rewrite_event);
4673 bruce@momjian.us 4304 :CBC 2230 : rev->relation = RelationGetRelid(rt_entry_relation);
4305 : 2230 : rev->event = event;
2433 tgl@sss.pgh.pa.us 4306 : 2230 : rewrite_events = lappend(rewrite_events, rev);
4307 : :
4673 bruce@momjian.us 4308 [ + - + + : 4505 : foreach(n, product_queries)
+ + ]
4309 : : {
4310 : 2347 : Query *pt = (Query *) lfirst(n);
4311 : : List *newstuff;
4312 : :
4313 : : /*
4314 : : * For an updatable view, pt might be the rewritten version of
4315 : : * the original query, in which case we pass on orig_rt_length
4316 : : * to finish processing any VALUES RTE it contained.
4317 : : *
4318 : : * Otherwise, we have a product query created by fireRules().
4319 : : * Any VALUES RTEs from the original query have been fully
4320 : : * processed, and must be skipped when we recurse.
4321 : : */
1198 dean.a.rasheed@gmail 4322 [ + + ]: 2347 : newstuff = RewriteQuery(pt, rewrite_events,
4323 : : pt == parsetree ?
4324 : : orig_rt_length :
4325 : : product_orig_rt_length,
4326 : : num_ctes_processed);
4673 bruce@momjian.us 4327 : 2275 : rewritten = list_concat(rewritten, newstuff);
4328 : : }
4329 : :
2433 tgl@sss.pgh.pa.us 4330 : 2158 : rewrite_events = list_delete_last(rewrite_events);
4331 : : }
4332 : :
4333 : : /*
4334 : : * If there is an INSTEAD, and the original query has a RETURNING, we
4335 : : * have to have found a RETURNING in the rule(s), else fail. (Because
4336 : : * DefineQueryRewrite only allows RETURNING in unconditional INSTEAD
4337 : : * rules, there's no need to worry whether the substituted RETURNING
4338 : : * will actually be executed --- it must be.)
4339 : : */
7134 4340 [ + + + + ]: 45245 : if ((instead || qual_product != NULL) &&
4341 [ + + ]: 2098 : parsetree->returningList &&
4342 [ + + ]: 243 : !returning)
4343 : : {
4344 [ + - - - ]: 3 : switch (event)
4345 : : {
4346 : 3 : case CMD_INSERT:
4347 [ + - ]: 3 : ereport(ERROR,
4348 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4349 : : errmsg("cannot perform INSERT RETURNING on relation \"%s\"",
4350 : : RelationGetRelationName(rt_entry_relation)),
4351 : : errhint("You need an unconditional ON INSERT DO INSTEAD rule with a RETURNING clause.")));
4352 : : break;
7134 tgl@sss.pgh.pa.us 4353 :UBC 0 : case CMD_UPDATE:
4354 [ # # ]: 0 : ereport(ERROR,
4355 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4356 : : errmsg("cannot perform UPDATE RETURNING on relation \"%s\"",
4357 : : RelationGetRelationName(rt_entry_relation)),
4358 : : errhint("You need an unconditional ON UPDATE DO INSTEAD rule with a RETURNING clause.")));
4359 : : break;
4360 : 0 : case CMD_DELETE:
4361 [ # # ]: 0 : ereport(ERROR,
4362 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4363 : : errmsg("cannot perform DELETE RETURNING on relation \"%s\"",
4364 : : RelationGetRelationName(rt_entry_relation)),
4365 : : errhint("You need an unconditional ON DELETE DO INSTEAD rule with a RETURNING clause.")));
4366 : : break;
4367 : 0 : default:
4368 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d",
4369 : : (int) event);
4370 : : break;
4371 : : }
4372 : : }
4373 : :
4374 : : /*
4375 : : * Updatable views are supported by ON CONFLICT, so don't prevent that
4376 : : * case from proceeding
4377 : : */
3964 andres@anarazel.de 4378 [ + + + + ]:CBC 45242 : if (parsetree->onConflict &&
4379 [ - + ]: 1161 : (product_queries != NIL || hasUpdate) &&
4380 [ + + ]: 129 : !updatableview)
3949 bruce@momjian.us 4381 [ + - ]: 6 : ereport(ERROR,
4382 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4383 : : errmsg("INSERT with ON CONFLICT clause cannot be used with table that has INSERT or UPDATE rules")));
4384 : :
2610 andres@anarazel.de 4385 : 45236 : table_close(rt_entry_relation, NoLock);
4386 : : }
4387 : :
4388 : : /*
4389 : : * For INSERTs, the original query is done first; for UPDATE/DELETE, it is
4390 : : * done last. This is needed because update and delete rule actions might
4391 : : * not do anything if they are invoked after the update or delete is
4392 : : * performed. The command counter increment between the query executions
4393 : : * makes the deleted (and maybe the updated) tuples disappear so the scans
4394 : : * for them in the rule actions cannot find them.
4395 : : *
4396 : : * If we found any unqualified INSTEAD, the original query is not done at
4397 : : * all, in any form. Otherwise, we add the modified form if qualified
4398 : : * INSTEADs were found, else the unmodified form.
4399 : : */
8548 tgl@sss.pgh.pa.us 4400 [ + + ]: 239204 : if (!instead)
4401 : : {
4402 [ + + ]: 237271 : if (parsetree->commandType == CMD_INSERT)
4403 : : {
4404 [ + + ]: 32939 : if (qual_product != NULL)
4405 : 147 : rewritten = lcons(qual_product, rewritten);
4406 : : else
4407 : 32792 : rewritten = lcons(parsetree, rewritten);
4408 : : }
4409 : : else
4410 : : {
4411 [ + + ]: 204332 : if (qual_product != NULL)
4412 : 9 : rewritten = lappend(rewritten, qual_product);
4413 : : else
4414 : 204323 : rewritten = lappend(rewritten, parsetree);
4415 : : }
4416 : : }
4417 : :
4418 : : /*
4419 : : * If the original query has a CTE list, and we generated more than one
4420 : : * non-utility result query, we have to fail because we'll have copied the
4421 : : * CTE list into each result query. That would break the expectation of
4422 : : * single evaluation of CTEs. This could possibly be fixed by
4423 : : * restructuring so that a CTE list can be shared across multiple Query
4424 : : * and PlannableStatement nodes.
4425 : : */
5395 4426 [ + + ]: 239204 : if (parsetree->cteList != NIL)
4427 : : {
5393 bruce@momjian.us 4428 : 1393 : int qcount = 0;
4429 : :
5395 tgl@sss.pgh.pa.us 4430 [ + - + + : 2786 : foreach(lc1, rewritten)
+ + ]
4431 : : {
4432 : 1393 : Query *q = (Query *) lfirst(lc1);
4433 : :
4434 [ + - ]: 1393 : if (q->commandType != CMD_UTILITY)
4435 : 1393 : qcount++;
4436 : : }
4437 [ - + ]: 1393 : if (qcount > 1)
5395 tgl@sss.pgh.pa.us 4438 [ # # ]:UBC 0 : ereport(ERROR,
4439 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4440 : : errmsg("WITH cannot be used in a query that is rewritten by rules into multiple queries")));
4441 : : }
4442 : :
10416 bruce@momjian.us 4443 :CBC 239204 : return rewritten;
4444 : : }
4445 : :
4446 : :
4447 : : /*
4448 : : * Expand virtual generated columns
4449 : : *
4450 : : * If the table contains virtual generated columns, build a target list
4451 : : * containing the expanded expressions and use ReplaceVarsFromTargetList() to
4452 : : * do the replacements.
4453 : : *
4454 : : * Vars matching rt_index at the current query level are replaced by the
4455 : : * virtual generated column expressions from rel, if there are any.
4456 : : *
4457 : : * The caller must also provide rte, the RTE describing the target relation,
4458 : : * in order to handle any whole-row Vars referencing the target, and
4459 : : * result_relation, the index of the result relation, if this is part of an
4460 : : * INSERT/UPDATE/DELETE/MERGE query.
4461 : : */
4462 : : static Node *
401 peter@eisentraut.org 4463 : 226 : expand_generated_columns_internal(Node *node, Relation rel, int rt_index,
4464 : : RangeTblEntry *rte, int result_relation)
4465 : : {
4466 : : TupleDesc tupdesc;
4467 : :
4468 : 226 : tupdesc = RelationGetDescr(rel);
4469 [ + - + - ]: 226 : if (tupdesc->constr && tupdesc->constr->has_generated_virtual)
4470 : : {
4471 : 226 : List *tlist = NIL;
4472 : :
4473 [ + + ]: 790 : for (int i = 0; i < tupdesc->natts; i++)
4474 : : {
4475 : 564 : Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
4476 : :
4477 [ + + ]: 564 : if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
4478 : : {
4479 : : Node *defexpr;
4480 : : TargetEntry *te;
4481 : :
383 rguo@postgresql.org 4482 : 235 : defexpr = build_generation_expression(rel, i + 1);
401 peter@eisentraut.org 4483 : 235 : ChangeVarNodes(defexpr, 1, rt_index, 0);
4484 : :
383 rguo@postgresql.org 4485 : 235 : te = makeTargetEntry((Expr *) defexpr, i + 1, 0, false);
401 peter@eisentraut.org 4486 : 235 : tlist = lappend(tlist, te);
4487 : : }
4488 : : }
4489 : :
4490 [ - + ]: 226 : Assert(list_length(tlist) > 0);
4491 : :
4492 : 226 : node = ReplaceVarsFromTargetList(node, rt_index, 0, rte, tlist,
4493 : : result_relation,
4494 : : REPLACEVARS_CHANGE_VARNO, rt_index,
4495 : : NULL);
4496 : : }
4497 : :
4498 : 226 : return node;
4499 : : }
4500 : :
4501 : : /*
4502 : : * Expand virtual generated columns in an expression
4503 : : *
4504 : : * This is for expressions that are not part of a query, such as default
4505 : : * expressions or index predicates. The rt_index is usually 1.
4506 : : */
4507 : : Node *
4508 : 6994 : expand_generated_columns_in_expr(Node *node, Relation rel, int rt_index)
4509 : : {
4510 : 6994 : TupleDesc tupdesc = RelationGetDescr(rel);
4511 : :
4512 [ + + + + ]: 6994 : if (tupdesc->constr && tupdesc->constr->has_generated_virtual)
4513 : : {
4514 : : RangeTblEntry *rte;
4515 : :
4516 : 226 : rte = makeNode(RangeTblEntry);
4517 : : /* eref needs to be set, but the actual name doesn't matter */
4518 : 226 : rte->eref = makeAlias(RelationGetRelationName(rel), NIL);
4519 : 226 : rte->rtekind = RTE_RELATION;
4520 : 226 : rte->relid = RelationGetRelid(rel);
4521 : :
4522 : 226 : node = expand_generated_columns_internal(node, rel, rt_index, rte, 0);
4523 : : }
4524 : :
4525 : 6994 : return node;
4526 : : }
4527 : :
4528 : : /*
4529 : : * Build the generation expression for the virtual generated column.
4530 : : *
4531 : : * Error out if there is no generation expression found for the given column.
4532 : : */
4533 : : Node *
383 rguo@postgresql.org 4534 : 1038 : build_generation_expression(Relation rel, int attrno)
4535 : : {
4536 : 1038 : TupleDesc rd_att = RelationGetDescr(rel);
4537 : 1038 : Form_pg_attribute att_tup = TupleDescAttr(rd_att, attrno - 1);
4538 : : Node *defexpr;
4539 : : Oid attcollid;
4540 : :
4541 [ + - - + ]: 1038 : Assert(rd_att->constr && rd_att->constr->has_generated_virtual);
4542 [ - + ]: 1038 : Assert(att_tup->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL);
4543 : :
4544 : 1038 : defexpr = build_column_default(rel, attrno);
4545 [ - + ]: 1038 : if (defexpr == NULL)
383 rguo@postgresql.org 4546 [ # # ]:UBC 0 : elog(ERROR, "no generation expression found for column number %d of table \"%s\"",
4547 : : attrno, RelationGetRelationName(rel));
4548 : :
4549 : : /*
4550 : : * If the column definition has a collation and it is different from the
4551 : : * collation of the generation expression, put a COLLATE clause around the
4552 : : * expression.
4553 : : */
383 rguo@postgresql.org 4554 :CBC 1038 : attcollid = att_tup->attcollation;
4555 [ + + + + ]: 1038 : if (attcollid && attcollid != exprCollation(defexpr))
4556 : : {
4557 : 6 : CollateExpr *ce = makeNode(CollateExpr);
4558 : :
4559 : 6 : ce->arg = (Expr *) defexpr;
4560 : 6 : ce->collOid = attcollid;
4561 : 6 : ce->location = -1;
4562 : :
4563 : 6 : defexpr = (Node *) ce;
4564 : : }
4565 : :
4566 : 1038 : return defexpr;
4567 : : }
4568 : :
4569 : :
4570 : : /*
4571 : : * QueryRewrite -
4572 : : * Primary entry point to the query rewriter.
4573 : : * Rewrite one query via query rewrite system, possibly returning 0
4574 : : * or many queries.
4575 : : *
4576 : : * NOTE: the parsetree must either have come straight from the parser,
4577 : : * or have been scanned by AcquireRewriteLocks to acquire suitable locks.
4578 : : */
4579 : : List *
9292 tgl@sss.pgh.pa.us 4580 : 237031 : QueryRewrite(Query *parsetree)
4581 : : {
289 drowley@postgresql.o 4582 : 237031 : int64 input_query_id = parsetree->queryId;
4583 : : List *querylist;
4584 : : List *results;
4585 : : ListCell *l;
4586 : : CmdType origCmdType;
4587 : : bool foundOriginalQuery;
4588 : : Query *lastInstead;
4589 : :
4590 : : /*
4591 : : * This function is only applied to top-level original queries
4592 : : */
5497 tgl@sss.pgh.pa.us 4593 [ - + ]: 237031 : Assert(parsetree->querySource == QSRC_ORIGINAL);
4594 [ - + ]: 237031 : Assert(parsetree->canSetTag);
4595 : :
4596 : : /*
4597 : : * Step 1
4598 : : *
4599 : : * Apply all non-SELECT rules possibly getting 0 or many queries
4600 : : */
106 dean.a.rasheed@gmail 4601 : 237031 : querylist = RewriteQuery(parsetree, NIL, 0, 0);
4602 : :
4603 : : /*
4604 : : * Step 2
4605 : : *
4606 : : * Apply all the RIR rules on each query
4607 : : *
4608 : : * This is also a handy place to mark each query with the original queryId
4609 : : */
5635 tgl@sss.pgh.pa.us 4610 : 236740 : results = NIL;
9791 bruce@momjian.us 4611 [ + + + + : 473750 : foreach(l, querylist)
+ + ]
4612 : : {
9124 4613 : 237067 : Query *query = (Query *) lfirst(l);
4614 : :
2892 tgl@sss.pgh.pa.us 4615 : 237067 : query = fireRIRrules(query, NIL);
4616 : :
5101 4617 : 237010 : query->queryId = input_query_id;
4618 : :
9292 4619 : 237010 : results = lappend(results, query);
4620 : : }
4621 : :
4622 : : /*
4623 : : * Step 3
4624 : : *
4625 : : * Determine which, if any, of the resulting queries is supposed to set
4626 : : * the command-result tag; and update the canSetTag fields accordingly.
4627 : : *
4628 : : * If the original query is still in the list, it sets the command tag.
4629 : : * Otherwise, the last INSTEAD query of the same kind as the original is
4630 : : * allowed to set the tag. (Note these rules can leave us with no query
4631 : : * setting the tag. The tcop code has to cope with this by setting up a
4632 : : * default tag based on the original un-rewritten query.)
4633 : : *
4634 : : * The Asserts verify that at most one query in the result list is marked
4635 : : * canSetTag. If we aren't checking asserts, we can fall out of the loop
4636 : : * as soon as we find the original query.
4637 : : */
8353 4638 : 236683 : origCmdType = parsetree->commandType;
4639 : 236683 : foundOriginalQuery = false;
4640 : 236683 : lastInstead = NULL;
4641 : :
4642 [ + + + + : 473693 : foreach(l, results)
+ + ]
4643 : : {
4644 : 237010 : Query *query = (Query *) lfirst(l);
4645 : :
4646 [ + + ]: 237010 : if (query->querySource == QSRC_ORIGINAL)
4647 : : {
4648 [ - + ]: 236347 : Assert(query->canSetTag);
4649 [ - + ]: 236347 : Assert(!foundOriginalQuery);
4650 : 236347 : foundOriginalQuery = true;
4651 : : #ifndef USE_ASSERT_CHECKING
4652 : : break;
4653 : : #endif
4654 : : }
4655 : : else
4656 : : {
4657 [ - + ]: 663 : Assert(!query->canSetTag);
4658 [ + + ]: 663 : if (query->commandType == origCmdType &&
4659 [ + + ]: 537 : (query->querySource == QSRC_INSTEAD_RULE ||
4660 [ + + ]: 264 : query->querySource == QSRC_QUAL_INSTEAD_RULE))
4661 : 387 : lastInstead = query;
4662 : : }
4663 : : }
4664 : :
4665 [ + + + + ]: 236683 : if (!foundOriginalQuery && lastInstead != NULL)
4666 : 285 : lastInstead->canSetTag = true;
4667 : :
9292 4668 : 236683 : return results;
4669 : : }
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