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/rewriteGraphTable.h"
40 : : #include "rewrite/rewriteHandler.h"
41 : : #include "rewrite/rewriteManip.h"
42 : : #include "rewrite/rewriteSearchCycle.h"
43 : : #include "rewrite/rowsecurity.h"
44 : : #include "tcop/tcopprot.h"
45 : : #include "utils/builtins.h"
46 : : #include "utils/lsyscache.h"
47 : : #include "utils/rel.h"
48 : :
49 : :
50 : : /* We use a list of these to detect recursion in RewriteQuery */
51 : : typedef struct rewrite_event
52 : : {
53 : : Oid relation; /* OID of relation having rules */
54 : : CmdType event; /* type of rule being fired */
55 : : } rewrite_event;
56 : :
57 : : typedef struct acquireLocksOnSubLinks_context
58 : : {
59 : : bool for_execute; /* AcquireRewriteLocks' forExecute param */
60 : : } acquireLocksOnSubLinks_context;
61 : :
62 : : typedef struct fireRIRonSubLink_context
63 : : {
64 : : List *activeRIRs;
65 : : bool hasRowSecurity;
66 : : } fireRIRonSubLink_context;
67 : :
68 : : static bool acquireLocksOnSubLinks(Node *node,
69 : : acquireLocksOnSubLinks_context *context);
70 : : static Query *rewriteRuleAction(Query *parsetree,
71 : : Query *rule_action,
72 : : Node *rule_qual,
73 : : int rt_index,
74 : : CmdType event,
75 : : bool *returning_flag);
76 : : static List *adjustJoinTreeList(Query *parsetree, bool removert, int rt_index);
77 : : static List *rewriteTargetListIU(List *targetList,
78 : : CmdType commandType,
79 : : OverridingKind override,
80 : : Relation target_relation,
81 : : RangeTblEntry *values_rte,
82 : : int values_rte_index,
83 : : Bitmapset **unused_values_attrnos);
84 : : static TargetEntry *process_matched_tle(TargetEntry *src_tle,
85 : : TargetEntry *prior_tle,
86 : : const char *attrName);
87 : : static Node *get_assignment_input(Node *node);
88 : : static Bitmapset *findDefaultOnlyColumns(RangeTblEntry *rte);
89 : : static bool rewriteValuesRTE(Query *parsetree, RangeTblEntry *rte, int rti,
90 : : Relation target_relation,
91 : : Bitmapset *unused_cols);
92 : : static void rewriteValuesRTEToNulls(Query *parsetree, RangeTblEntry *rte);
93 : : static void markQueryForLocking(Query *qry, Node *jtnode,
94 : : LockClauseStrength strength, LockWaitPolicy waitPolicy,
95 : : bool pushedDown);
96 : : static List *matchLocks(CmdType event, Relation relation,
97 : : int varno, Query *parsetree, bool *hasUpdate);
98 : : static Query *fireRIRrules(Query *parsetree, List *activeRIRs);
99 : : static Bitmapset *adjust_view_column_set(Bitmapset *cols, List *targetlist);
100 : : static List *get_generated_columns(Relation rel, int rt_index, bool include_stored);
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
4443 tgl@sss.pgh.pa.us 148 :CBC 30047 : AcquireRewriteLocks(Query *parsetree,
149 : : bool forExecute,
150 : : bool forUpdatePushedDown)
151 : : {
152 : : ListCell *l;
153 : : int rt_index;
154 : : acquireLocksOnSubLinks_context context;
155 : :
156 : 30047 : context.for_execute = forExecute;
157 : :
158 : : /*
159 : : * First, process RTEs of the current query level.
160 : : */
7641 161 : 30047 : rt_index = 0;
162 [ + + + + : 99989 : foreach(l, parsetree->rtable)
+ + ]
163 : : {
164 : 69942 : 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 : 69942 : ++rt_index;
173 [ + + + + ]: 69942 : switch (rte->rtekind)
174 : : {
175 : 40513 : case RTE_RELATION:
176 : : case RTE_GRAPH_TABLE:
177 : :
178 : : /*
179 : : * Grab the appropriate lock type for the relation, and do not
180 : : * release it until end of transaction. This protects the
181 : : * rewriter, planner, and executor against schema changes
182 : : * mid-query.
183 : : *
184 : : * If forExecute is false, ignore rellockmode and just use
185 : : * AccessShareLock.
186 : : */
4443 187 [ + + ]: 40513 : if (!forExecute)
188 : 4763 : lockmode = AccessShareLock;
2774 189 [ + + ]: 35750 : else if (forUpdatePushedDown)
190 : : {
191 : : /* Upgrade RTE's lock mode to reflect pushed-down lock */
192 [ + - ]: 64 : if (rte->rellockmode == AccessShareLock)
193 : 64 : rte->rellockmode = RowShareLock;
2772 194 : 64 : lockmode = rte->rellockmode;
195 : : }
196 : : else
197 : 35686 : lockmode = rte->rellockmode;
198 : :
55 peter@eisentraut.org 199 :GNC 40513 : rel = relation_open(rte->relid, lockmode);
200 : :
201 : : /*
202 : : * While we have the relation open, update the RTE's relkind,
203 : : * just in case it changed since this rule was made.
204 : : */
5551 tgl@sss.pgh.pa.us 205 :CBC 40513 : rte->relkind = rel->rd_rel->relkind;
206 : :
55 peter@eisentraut.org 207 :GNC 40513 : relation_close(rel, NoLock);
7641 tgl@sss.pgh.pa.us 208 :CBC 40513 : break;
209 : :
210 : 16383 : case RTE_JOIN:
211 : :
212 : : /*
213 : : * Scan the join's alias var list to see if any columns have
214 : : * been dropped, and if so replace those Vars with null
215 : : * pointers.
216 : : *
217 : : * Since a join has only two inputs, we can expect to see
218 : : * multiple references to the same input RTE; optimize away
219 : : * multiple fetches.
220 : : */
221 : 16383 : newaliasvars = NIL;
7640 222 : 16383 : curinputvarno = 0;
223 : 16383 : curinputrte = NULL;
7641 224 [ + - + + : 640807 : foreach(ll, rte->joinaliasvars)
+ + ]
225 : : {
4669 226 : 624424 : Var *aliasitem = (Var *) lfirst(ll);
227 : 624424 : Var *aliasvar = aliasitem;
228 : :
229 : : /* Look through any implicit coercion */
230 : 624424 : aliasvar = (Var *) strip_implicit_coercions((Node *) aliasvar);
231 : :
232 : : /*
233 : : * If the list item isn't a simple Var, then it must
234 : : * represent a merged column, ie a USING column, and so it
235 : : * couldn't possibly be dropped, since it's referenced in
236 : : * the join clause. (Conceivably it could also be a null
237 : : * pointer already? But that's OK too.)
238 : : */
239 [ + - + + ]: 624424 : if (aliasvar && IsA(aliasvar, Var))
240 : : {
241 : : /*
242 : : * The elements of an alias list have to refer to
243 : : * earlier RTEs of the same rtable, because that's the
244 : : * order the planner builds things in. So we already
245 : : * processed the referenced RTE, and so it's safe to
246 : : * use get_rte_attribute_is_dropped on it. (This might
247 : : * not hold after rewriting or planning, but it's OK
248 : : * to assume here.)
249 : : */
7641 250 [ - + ]: 624308 : Assert(aliasvar->varlevelsup == 0);
7640 251 [ + + ]: 624308 : if (aliasvar->varno != curinputvarno)
252 : : {
253 : 43105 : curinputvarno = aliasvar->varno;
254 [ - + ]: 43105 : if (curinputvarno >= rt_index)
7640 tgl@sss.pgh.pa.us 255 [ # # ]:UBC 0 : elog(ERROR, "unexpected varno %d in JOIN RTE %d",
256 : : curinputvarno, rt_index);
7640 tgl@sss.pgh.pa.us 257 :CBC 43105 : curinputrte = rt_fetch(curinputvarno,
258 : : parsetree->rtable);
259 : : }
260 [ + + ]: 624308 : if (get_rte_attribute_is_dropped(curinputrte,
261 : 624308 : aliasvar->varattno))
262 : : {
263 : : /* Replace the join alias item with a NULL */
4669 264 : 4 : aliasitem = NULL;
265 : : }
266 : : }
267 : 624424 : newaliasvars = lappend(newaliasvars, aliasitem);
268 : : }
7641 269 : 16383 : rte->joinaliasvars = newaliasvars;
270 : 16383 : break;
271 : :
272 : 6203 : case RTE_SUBQUERY:
273 : :
274 : : /*
275 : : * The subquery RTE itself is all right, but we have to
276 : : * recurse to process the represented subquery.
277 : : */
6033 278 : 6203 : AcquireRewriteLocks(rte->subquery,
279 : : forExecute,
280 [ + - - + ]: 12406 : (forUpdatePushedDown ||
3240 281 : 6203 : get_parse_rowmark(parsetree, rt_index) != NULL));
7641 282 : 6203 : break;
283 : :
284 : 6843 : default:
285 : : /* ignore other types of RTEs */
286 : 6843 : break;
287 : : }
288 : : }
289 : :
290 : : /* Recurse into subqueries in WITH */
6422 291 [ + + + + : 30248 : foreach(l, parsetree->cteList)
+ + ]
292 : : {
293 : 201 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(l);
294 : :
4443 295 : 201 : AcquireRewriteLocks((Query *) cte->ctequery, forExecute, false);
296 : : }
297 : :
298 : : /*
299 : : * Recurse into sublink subqueries, too. But we already did the ones in
300 : : * the rtable and cteList.
301 : : */
7641 302 [ + + ]: 30047 : if (parsetree->hasSubLinks)
4443 303 : 1434 : query_tree_walker(parsetree, acquireLocksOnSubLinks, &context,
304 : : QTW_IGNORE_RC_SUBQUERIES);
7641 305 : 30047 : }
306 : :
307 : : /*
308 : : * Walker to find sublink subqueries for AcquireRewriteLocks
309 : : */
310 : : static bool
4443 311 : 132930 : acquireLocksOnSubLinks(Node *node, acquireLocksOnSubLinks_context *context)
312 : : {
7641 313 [ + + ]: 132930 : if (node == NULL)
314 : 27659 : return false;
315 [ + + ]: 105271 : if (IsA(node, SubLink))
316 : : {
317 : 3026 : SubLink *sub = (SubLink *) node;
318 : :
319 : : /* Do what we came for */
4443 320 : 3026 : AcquireRewriteLocks((Query *) sub->subselect,
321 : 3026 : context->for_execute,
322 : : false);
323 : : /* Fall through to process lefthand args of SubLink */
324 : : }
325 : :
326 : : /*
327 : : * Do NOT recurse into Query nodes, because AcquireRewriteLocks already
328 : : * processed subselects of subselects for us.
329 : : */
7641 330 : 105271 : return expression_tree_walker(node, acquireLocksOnSubLinks, context);
331 : : }
332 : :
333 : :
334 : : /*
335 : : * rewriteRuleAction -
336 : : * Rewrite the rule action with appropriate qualifiers (taken from
337 : : * the triggering query).
338 : : *
339 : : * Input arguments:
340 : : * parsetree - original query
341 : : * rule_action - one action (query) of a rule
342 : : * rule_qual - WHERE condition of rule, or NULL if unconditional
343 : : * rt_index - RT index of result relation in original query
344 : : * event - type of rule event
345 : : * Output arguments:
346 : : * *returning_flag - set true if we rewrite RETURNING clause in rule_action
347 : : * (must be initialized to false)
348 : : * Return value:
349 : : * rewritten form of rule_action
350 : : */
351 : : static Query *
9092 352 : 988 : rewriteRuleAction(Query *parsetree,
353 : : Query *rule_action,
354 : : Node *rule_qual,
355 : : int rt_index,
356 : : CmdType event,
357 : : bool *returning_flag)
358 : : {
359 : : int current_varno,
360 : : new_varno;
361 : : int rt_length;
362 : : Query *sub_action;
363 : : Query **sub_action_ptr;
364 : : acquireLocksOnSubLinks_context context;
365 : : ListCell *lc;
366 : :
4443 367 : 988 : context.for_execute = true;
368 : :
369 : : /*
370 : : * Make modifiable copies of rule action and qual (what we're passed are
371 : : * the stored versions in the relcache; don't touch 'em!).
372 : : */
3344 peter_e@gmx.net 373 : 988 : rule_action = copyObject(rule_action);
374 : 988 : rule_qual = copyObject(rule_qual);
375 : :
376 : : /*
377 : : * Acquire necessary locks and fix any deleted JOIN RTE entries.
378 : : */
4443 tgl@sss.pgh.pa.us 379 : 988 : AcquireRewriteLocks(rule_action, true, false);
380 : 988 : (void) acquireLocksOnSubLinks(rule_qual, &context);
381 : :
9092 382 : 988 : current_varno = rt_index;
8010 neilc@samurai.com 383 : 988 : rt_length = list_length(parsetree->rtable);
9092 tgl@sss.pgh.pa.us 384 : 988 : new_varno = PRS2_NEW_VARNO + rt_length;
385 : :
386 : : /*
387 : : * Adjust rule action and qual to offset its varnos, so that we can merge
388 : : * its rtable with the main parsetree's rtable.
389 : : *
390 : : * If the rule action is an INSERT...SELECT, the OLD/NEW rtable entries
391 : : * will be in the SELECT part, and we have to modify that rather than the
392 : : * top-level INSERT (kluge!).
393 : : */
394 : 988 : sub_action = getInsertSelectQuery(rule_action, &sub_action_ptr);
395 : :
9282 396 : 988 : OffsetVarNodes((Node *) sub_action, rt_length, 0);
9092 397 : 988 : OffsetVarNodes(rule_qual, rt_length, 0);
398 : : /* but references to OLD should point at original rt_index */
9282 399 : 988 : ChangeVarNodes((Node *) sub_action,
400 : : PRS2_OLD_VARNO + rt_length, rt_index, 0);
9092 401 : 988 : ChangeVarNodes(rule_qual,
402 : : PRS2_OLD_VARNO + rt_length, rt_index, 0);
403 : :
404 : : /*
405 : : * Mark any subquery RTEs in the rule action as LATERAL if they contain
406 : : * Vars referring to the current query level (references to NEW/OLD).
407 : : * Those really are lateral references, but we've historically not
408 : : * required users to mark such subqueries with LATERAL explicitly. But
409 : : * the planner will complain if such Vars exist in a non-LATERAL subquery,
410 : : * so we have to fix things up here.
411 : : */
1165 dean.a.rasheed@gmail 412 [ + + + + : 3932 : foreach(lc, sub_action->rtable)
+ + ]
413 : : {
414 : 2944 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
415 : :
416 [ + + + - : 2952 : if (rte->rtekind == RTE_SUBQUERY && !rte->lateral &&
+ - ]
417 : 8 : contain_vars_of_level((Node *) rte->subquery, 1))
418 : 8 : rte->lateral = true;
419 : : }
420 : :
421 : : /*
422 : : * Generate expanded rtable consisting of main parsetree's rtable plus
423 : : * rule action's rtable; this becomes the complete rtable for the rule
424 : : * action. Some of the entries may be unused after we finish rewriting,
425 : : * but we leave them all in place to avoid having to adjust the query's
426 : : * varnos. RT entries that are not referenced in the completed jointree
427 : : * will be ignored by the planner, so they do not affect query semantics.
428 : : *
429 : : * Also merge RTEPermissionInfo lists to ensure that all permissions are
430 : : * checked correctly.
431 : : *
432 : : * If the rule is INSTEAD, then the original query won't be executed at
433 : : * all, and so its rteperminfos must be preserved so that the executor
434 : : * will do the correct permissions checks on the relations referenced in
435 : : * it. This allows us to check that the caller has, say, insert-permission
436 : : * on a view, when the view is not semantically referenced at all in the
437 : : * resulting query.
438 : : *
439 : : * When a rule is not INSTEAD, the permissions checks done using the
440 : : * copied entries will be redundant with those done during execution of
441 : : * the original query, but we don't bother to treat that case differently.
442 : : *
443 : : * NOTE: because planner will destructively alter rtable and rteperminfos,
444 : : * we must ensure that rule action's lists are separate and shares no
445 : : * substructure with the main query's lists. Hence do a deep copy here
446 : : * for both.
447 : : */
448 : : {
1246 alvherre@alvh.no-ip. 449 : 988 : List *rtable_tail = sub_action->rtable;
450 : 988 : List *perminfos_tail = sub_action->rteperminfos;
451 : :
452 : : /*
453 : : * RewriteQuery relies on the fact that RT entries from the original
454 : : * query appear at the start of the expanded rtable, so we put the
455 : : * action's original table at the end of the list.
456 : : */
457 : 988 : sub_action->rtable = copyObject(parsetree->rtable);
458 : 988 : sub_action->rteperminfos = copyObject(parsetree->rteperminfos);
459 : 988 : CombineRangeTables(&sub_action->rtable, &sub_action->rteperminfos,
460 : : rtable_tail, perminfos_tail);
461 : : }
462 : :
463 : : /*
464 : : * There could have been some SubLinks in parsetree's rtable, in which
465 : : * case we'd better mark the sub_action correctly.
466 : : */
6432 tgl@sss.pgh.pa.us 467 [ + + + - ]: 988 : if (parsetree->hasSubLinks && !sub_action->hasSubLinks)
468 : : {
469 [ + - + + : 60 : foreach(lc, parsetree->rtable)
+ + ]
470 : : {
471 : 40 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
472 : :
473 [ + - - - : 40 : switch (rte->rtekind)
+ ]
474 : : {
3937 475 : 36 : case RTE_RELATION:
476 : 36 : sub_action->hasSubLinks =
477 : 36 : checkExprHasSubLink((Node *) rte->tablesample);
478 : 36 : break;
6432 tgl@sss.pgh.pa.us 479 :UBC 0 : case RTE_FUNCTION:
480 : 0 : sub_action->hasSubLinks =
4548 481 : 0 : checkExprHasSubLink((Node *) rte->functions);
6432 482 : 0 : break;
3345 alvherre@alvh.no-ip. 483 : 0 : case RTE_TABLEFUNC:
484 : 0 : sub_action->hasSubLinks =
485 : 0 : checkExprHasSubLink((Node *) rte->tablefunc);
486 : 0 : break;
6432 tgl@sss.pgh.pa.us 487 : 0 : case RTE_VALUES:
488 : 0 : sub_action->hasSubLinks =
489 : 0 : checkExprHasSubLink((Node *) rte->values_lists);
490 : 0 : break;
6432 tgl@sss.pgh.pa.us 491 :CBC 4 : default:
492 : : /* other RTE types don't contain bare expressions */
493 : 4 : break;
494 : : }
1057 495 : 40 : sub_action->hasSubLinks |=
496 : 40 : checkExprHasSubLink((Node *) rte->securityQuals);
6432 497 [ + + ]: 40 : if (sub_action->hasSubLinks)
6172 bruce@momjian.us 498 : 4 : break; /* no need to keep scanning rtable */
499 : : }
500 : : }
501 : :
502 : : /*
503 : : * Also, we might have absorbed some RTEs with RLS conditions into the
504 : : * sub_action. If so, mark it as hasRowSecurity, whether or not those
505 : : * RTEs will be referenced after we finish rewriting. (Note: currently
506 : : * this is a no-op because RLS conditions aren't added till later, but it
507 : : * seems like good future-proofing to do this anyway.)
508 : : */
3463 tgl@sss.pgh.pa.us 509 : 988 : sub_action->hasRowSecurity |= parsetree->hasRowSecurity;
510 : :
511 : : /*
512 : : * Each rule action's jointree should be the main parsetree's jointree
513 : : * plus that rule's jointree, but usually *without* the original rtindex
514 : : * that we're replacing (if present, which it won't be for INSERT). Note
515 : : * that if the rule action refers to OLD, its jointree will add a
516 : : * reference to rt_index. If the rule action doesn't refer to OLD, but
517 : : * either the rule_qual or the user query quals do, then we need to keep
518 : : * the original rtindex in the jointree to provide data for the quals. We
519 : : * don't want the original rtindex to be joined twice, however, so avoid
520 : : * keeping it if the rule action mentions it.
521 : : *
522 : : * As above, the action's jointree must not share substructure with the
523 : : * main parsetree's.
524 : : */
8329 525 [ + + ]: 988 : if (sub_action->commandType != CMD_UTILITY)
526 : : {
527 : : bool keeporig;
528 : : List *newjointree;
529 : :
530 [ - + ]: 968 : Assert(sub_action->jointree != NULL);
9175 bruce@momjian.us 531 : 968 : keeporig = (!rangeTableEntry_used((Node *) sub_action->jointree,
532 [ + + + - ]: 2280 : rt_index, 0)) &&
9092 tgl@sss.pgh.pa.us 533 [ + + ]: 1312 : (rangeTableEntry_used(rule_qual, rt_index, 0) ||
7507 bruce@momjian.us 534 : 656 : rangeTableEntry_used(parsetree->jointree->quals, rt_index, 0));
9229 tgl@sss.pgh.pa.us 535 : 968 : newjointree = adjustJoinTreeList(parsetree, !keeporig, rt_index);
8329 536 [ + + ]: 968 : if (newjointree != NIL)
537 : : {
538 : : /*
539 : : * If sub_action is a setop, manipulating its jointree will do no
540 : : * good at all, because the jointree is dummy. (Perhaps someday
541 : : * we could push the joining and quals down to the member
542 : : * statements of the setop?)
543 : : */
544 [ - + ]: 196 : if (sub_action->setOperations != NULL)
8320 tgl@sss.pgh.pa.us 545 [ # # ]:UBC 0 : ereport(ERROR,
546 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
547 : : errmsg("conditional UNION/INTERSECT/EXCEPT statements are not implemented")));
548 : :
8329 tgl@sss.pgh.pa.us 549 :CBC 392 : sub_action->jointree->fromlist =
8010 neilc@samurai.com 550 : 196 : list_concat(newjointree, sub_action->jointree->fromlist);
551 : :
552 : : /*
553 : : * There could have been some SubLinks in newjointree, in which
554 : : * case we'd better mark the sub_action correctly.
555 : : */
7468 tgl@sss.pgh.pa.us 556 [ + + + - ]: 196 : if (parsetree->hasSubLinks && !sub_action->hasSubLinks)
557 : 4 : sub_action->hasSubLinks =
558 : 4 : checkExprHasSubLink((Node *) newjointree);
559 : : }
560 : : }
561 : :
562 : : /*
563 : : * If the original query has any CTEs, copy them into the rule action. But
564 : : * we don't need them for a utility action.
565 : : */
5446 566 [ + + + - ]: 988 : if (parsetree->cteList != NIL && sub_action->commandType != CMD_UTILITY)
567 : : {
568 : : /*
569 : : * Annoying implementation restriction: because CTEs are identified by
570 : : * name within a cteList, we can't merge a CTE from the original query
571 : : * if it has the same name as any CTE in the rule action.
572 : : *
573 : : * This could possibly be fixed by using some sort of internally
574 : : * generated ID, instead of names, to link CTE RTEs to their CTEs.
575 : : * However, decompiling the results would be quite confusing; note the
576 : : * merge of hasRecursive flags below, which could change the apparent
577 : : * semantics of such redundantly-named CTEs.
578 : : */
579 [ + - + + : 48 : foreach(lc, parsetree->cteList)
+ + ]
580 : : {
581 : 24 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
582 : : ListCell *lc2;
583 : :
584 [ + + + + : 28 : foreach(lc2, sub_action->cteList)
+ + ]
585 : : {
586 : 4 : CommonTableExpr *cte2 = (CommonTableExpr *) lfirst(lc2);
587 : :
588 [ - + ]: 4 : if (strcmp(cte->ctename, cte2->ctename) == 0)
5446 tgl@sss.pgh.pa.us 589 [ # # ]:UBC 0 : ereport(ERROR,
590 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
591 : : errmsg("WITH query name \"%s\" appears in both a rule action and the query being rewritten",
592 : : cte->ctename)));
593 : : }
594 : : }
595 : :
596 : : /*
597 : : * OK, it's safe to combine the CTE lists. Beware that RewriteQuery
598 : : * knows we concatenate the lists in this order.
599 : : */
5446 tgl@sss.pgh.pa.us 600 :CBC 24 : sub_action->cteList = list_concat(sub_action->cteList,
601 : 24 : copyObject(parsetree->cteList));
602 : : /* ... and don't forget about the associated flags */
1700 603 : 24 : sub_action->hasRecursive |= parsetree->hasRecursive;
604 : 24 : sub_action->hasModifyingCTE |= parsetree->hasModifyingCTE;
605 : :
606 : : /*
607 : : * If rule_action is different from sub_action (i.e., the rule action
608 : : * is an INSERT...SELECT), then we might have just added some
609 : : * data-modifying CTEs that are not at the top query level. This is
610 : : * disallowed by the parser and we mustn't generate such trees here
611 : : * either, so throw an error.
612 : : *
613 : : * Conceivably such cases could be supported by attaching the original
614 : : * query's CTEs to rule_action not sub_action. But to do that, we'd
615 : : * have to increment ctelevelsup in RTEs and SubLinks copied from the
616 : : * original query. For now, it doesn't seem worth the trouble.
617 : : */
618 [ + + + + ]: 24 : if (sub_action->hasModifyingCTE && rule_action != sub_action)
619 [ + - ]: 4 : ereport(ERROR,
620 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
621 : : errmsg("INSERT ... SELECT rule actions are not supported for queries having data-modifying statements in WITH")));
622 : : }
623 : :
624 : : /*
625 : : * Event Qualification forces copying of parsetree and splitting into two
626 : : * queries one w/rule_qual, one w/NOT rule_qual. Also add user query qual
627 : : * onto rule action
628 : : */
9092 629 : 984 : AddQual(sub_action, rule_qual);
630 : :
9282 631 : 984 : AddQual(sub_action, parsetree->jointree->quals);
632 : :
633 : : /*
634 : : * Rewrite new.attribute with right hand side of target-list entry for
635 : : * appropriate field name in insert/update.
636 : : *
637 : : * KLUGE ALERT: since ReplaceVarsFromTargetList returns a mutated copy, we
638 : : * can't just apply it to sub_action; we have to remember to update the
639 : : * sublink inside rule_action, too.
640 : : */
7941 641 [ + + + + ]: 984 : if ((event == CMD_INSERT || event == CMD_UPDATE) &&
642 [ + + ]: 864 : sub_action->commandType != CMD_UTILITY)
643 : : {
14 rguo@postgresql.org 644 : 844 : RangeTblEntry *new_rte = rt_fetch(new_varno, sub_action->rtable);
645 : : Relation new_rel;
646 : : List *gen_cols;
647 : :
648 : : /*
649 : : * The target list does not contain entries for generated columns
650 : : * (they are removed by rewriteTargetListIU), so we must build entries
651 : : * for them here, so that new.gen_col can be rewritten correctly.
652 : : */
653 : 844 : new_rel = relation_open(new_rte->relid, NoLock);
654 : 844 : gen_cols = get_generated_columns(new_rel, new_varno, true);
655 : 844 : relation_close(new_rel, NoLock);
656 : :
657 : : /*
658 : : * The generated column expressions refer to new.attribute, so they
659 : : * must be rewritten before they can be used as replacements.
660 : : */
661 : : gen_cols = (List *)
662 [ + + ]: 844 : ReplaceVarsFromTargetList((Node *) gen_cols,
663 : : new_varno,
664 : : 0,
665 : : new_rte,
666 : : parsetree->targetList,
667 : : sub_action->resultRelation,
668 : : (event == CMD_UPDATE) ?
669 : : REPLACEVARS_CHANGE_VARNO :
670 : : REPLACEVARS_SUBSTITUTE_NULL,
671 : : current_varno,
672 : : &sub_action->hasSubLinks);
673 : :
674 : : /*
675 : : * Now rewrite new.attribute in sub_action, using both the target list
676 : : * and the rewritten generated column expressions.
677 : : */
678 : : sub_action = (Query *)
4926 tgl@sss.pgh.pa.us 679 [ + + ]: 1688 : ReplaceVarsFromTargetList((Node *) sub_action,
680 : : new_varno,
681 : : 0,
682 : : new_rte,
14 rguo@postgresql.org 683 : 844 : list_concat(gen_cols, parsetree->targetList),
684 : : sub_action->resultRelation,
685 : : (event == CMD_UPDATE) ?
686 : : REPLACEVARS_CHANGE_VARNO :
687 : : REPLACEVARS_SUBSTITUTE_NULL,
688 : : current_varno,
689 : : NULL);
9282 tgl@sss.pgh.pa.us 690 [ + + ]: 844 : if (sub_action_ptr)
691 : 36 : *sub_action_ptr = sub_action;
692 : : else
9092 693 : 808 : rule_action = sub_action;
694 : : }
695 : :
696 : : /*
697 : : * If rule_action is INSERT .. ON CONFLICT DO SELECT, the parser should
698 : : * have verified that it has a RETURNING clause, but we must also check
699 : : * that the triggering query has a RETURNING clause.
700 : : */
82 dean.a.rasheed@gmail 701 [ + + ]:GNC 984 : if (rule_action->onConflict &&
702 [ + + ]: 52 : rule_action->onConflict->action == ONCONFLICT_SELECT &&
703 [ + - + + ]: 20 : (!rule_action->returningList || !parsetree->returningList))
704 [ + - ]: 4 : ereport(ERROR,
705 : : errcode(ERRCODE_SYNTAX_ERROR),
706 : : errmsg("ON CONFLICT DO SELECT requires a RETURNING clause"),
707 : : errdetail("A rule action is INSERT ... ON CONFLICT DO SELECT, which requires a RETURNING clause."));
708 : :
709 : : /*
710 : : * If rule_action has a RETURNING clause, then either throw it away if the
711 : : * triggering query has no RETURNING clause, or rewrite it to emit what
712 : : * the triggering query's RETURNING clause asks for. Throw an error if
713 : : * more than one rule has a RETURNING clause.
714 : : */
7185 tgl@sss.pgh.pa.us 715 [ + + ]:CBC 980 : if (!parsetree->returningList)
716 : 860 : rule_action->returningList = NIL;
717 [ + + ]: 120 : else if (rule_action->returningList)
718 : : {
719 [ - + ]: 112 : if (*returning_flag)
7185 tgl@sss.pgh.pa.us 720 [ # # ]:UBC 0 : ereport(ERROR,
721 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
722 : : errmsg("cannot have RETURNING lists in multiple rules")));
7185 tgl@sss.pgh.pa.us 723 :CBC 112 : *returning_flag = true;
724 : 112 : rule_action->returningList = (List *)
4926 725 : 112 : ReplaceVarsFromTargetList((Node *) parsetree->returningList,
726 : : parsetree->resultRelation,
727 : : 0,
728 : 112 : rt_fetch(parsetree->resultRelation,
729 : : parsetree->rtable),
730 : : rule_action->returningList,
731 : : rule_action->resultRelation,
732 : : REPLACEVARS_REPORT_ERROR,
733 : : 0,
734 : : &rule_action->hasSubLinks);
735 : :
736 : : /* use triggering query's aliases for OLD and NEW in RETURNING list */
474 dean.a.rasheed@gmail 737 : 112 : rule_action->returningOldAlias = parsetree->returningOldAlias;
738 : 112 : rule_action->returningNewAlias = parsetree->returningNewAlias;
739 : :
740 : : /*
741 : : * There could have been some SubLinks in parsetree's returningList,
742 : : * in which case we'd better mark the rule_action correctly.
743 : : */
6432 tgl@sss.pgh.pa.us 744 [ - + - - ]: 112 : if (parsetree->hasSubLinks && !rule_action->hasSubLinks)
6432 tgl@sss.pgh.pa.us 745 :UBC 0 : rule_action->hasSubLinks =
6172 bruce@momjian.us 746 : 0 : checkExprHasSubLink((Node *) rule_action->returningList);
747 : : }
748 : :
9092 tgl@sss.pgh.pa.us 749 :CBC 980 : return rule_action;
750 : : }
751 : :
752 : : /*
753 : : * Copy the query's jointree list, and optionally attempt to remove any
754 : : * occurrence of the given rt_index as a top-level join item (we do not look
755 : : * for it within join items; this is OK because we are only expecting to find
756 : : * it as an UPDATE or DELETE target relation, which will be at the top level
757 : : * of the join). Returns modified jointree list --- this is a separate copy
758 : : * sharing no nodes with the original.
759 : : */
760 : : static List *
9229 761 : 968 : adjustJoinTreeList(Query *parsetree, bool removert, int rt_index)
762 : : {
9093 763 : 968 : List *newjointree = copyObject(parsetree->jointree->fromlist);
764 : : ListCell *l;
765 : :
9229 766 [ + + ]: 968 : if (removert)
767 : : {
8014 neilc@samurai.com 768 [ + + + + : 1116 : foreach(l, newjointree)
+ + ]
769 : : {
770 : 508 : RangeTblRef *rtr = lfirst(l);
771 : :
8540 tgl@sss.pgh.pa.us 772 [ + - ]: 508 : if (IsA(rtr, RangeTblRef) &&
773 [ + + ]: 508 : rtr->rtindex == rt_index)
774 : : {
2021 drowley@postgresql.o 775 : 348 : newjointree = foreach_delete_current(newjointree, l);
9229 tgl@sss.pgh.pa.us 776 : 348 : break;
777 : : }
778 : : }
779 : : }
9366 780 : 968 : return newjointree;
781 : : }
782 : :
783 : :
784 : : /*
785 : : * rewriteTargetListIU - rewrite INSERT/UPDATE targetlist into standard form
786 : : *
787 : : * This has the following responsibilities:
788 : : *
789 : : * 1. For an INSERT, add tlist entries to compute default values for any
790 : : * attributes that have defaults and are not assigned to in the given tlist.
791 : : * (We do not insert anything for default-less attributes, however. The
792 : : * planner will later insert NULLs for them, but there's no reason to slow
793 : : * down rewriter processing with extra tlist nodes.) Also, for both INSERT
794 : : * and UPDATE, replace explicit DEFAULT specifications with column default
795 : : * expressions.
796 : : *
797 : : * 2. Merge multiple entries for the same target attribute, or declare error
798 : : * if we can't. Multiple entries are only allowed for INSERT/UPDATE of
799 : : * portions of an array or record field, for example
800 : : * UPDATE table SET foo[2] = 42, foo[4] = 43;
801 : : * We can merge such operations into a single assignment op. Essentially,
802 : : * the expression we want to produce in this case is like
803 : : * foo = array_set_element(array_set_element(foo, 2, 42), 4, 43)
804 : : *
805 : : * 3. Sort the tlist into standard order: non-junk fields in order by resno,
806 : : * then junk fields (these in no particular order).
807 : : *
808 : : * We must do items 1 and 2 before firing rewrite rules, else rewritten
809 : : * references to NEW.foo will produce wrong or incomplete results. Item 3
810 : : * is not needed for rewriting, but it is helpful for the planner, and we
811 : : * can do it essentially for free while handling the other items.
812 : : *
813 : : * If values_rte is non-NULL (i.e., we are doing a multi-row INSERT using
814 : : * values from a VALUES RTE), we populate *unused_values_attrnos with the
815 : : * attribute numbers of any unused columns from the VALUES RTE. This can
816 : : * happen for identity and generated columns whose targetlist entries are
817 : : * replaced with generated expressions (if INSERT ... OVERRIDING USER VALUE is
818 : : * used, or all the values to be inserted are DEFAULT). This information is
819 : : * required by rewriteValuesRTE() to handle any DEFAULT items in the unused
820 : : * columns. The caller must have initialized *unused_values_attrnos to NULL.
821 : : */
822 : : static List *
4015 andres@anarazel.de 823 : 54594 : rewriteTargetListIU(List *targetList,
824 : : CmdType commandType,
825 : : OverridingKind override,
826 : : Relation target_relation,
827 : : RangeTblEntry *values_rte,
828 : : int values_rte_index,
829 : : Bitmapset **unused_values_attrnos)
830 : : {
831 : : TargetEntry **new_tles;
8796 tgl@sss.pgh.pa.us 832 : 54594 : List *new_tlist = NIL;
7710 833 : 54594 : List *junk_tlist = NIL;
834 : : Form_pg_attribute att_tup;
835 : : int attrno,
836 : : next_junk_attrno,
837 : : numattrs;
838 : : ListCell *temp;
1990 839 : 54594 : Bitmapset *default_only_cols = NULL;
840 : :
841 : : /*
842 : : * We process the normal (non-junk) attributes by scanning the input tlist
843 : : * once and transferring TLEs into an array, then scanning the array to
844 : : * build an output tlist. This avoids O(N^2) behavior for large numbers
845 : : * of attributes.
846 : : *
847 : : * Junk attributes are tossed into a separate list during the same tlist
848 : : * scan, then appended to the reconstructed tlist.
849 : : */
8796 850 : 54594 : numattrs = RelationGetNumberOfAttributes(target_relation);
7710 851 : 54594 : new_tles = (TargetEntry **) palloc0(numattrs * sizeof(TargetEntry *));
852 : 54594 : next_junk_attrno = numattrs + 1;
853 : :
4015 andres@anarazel.de 854 [ + + + + : 153732 : foreach(temp, targetList)
+ + ]
855 : : {
7710 tgl@sss.pgh.pa.us 856 : 99150 : TargetEntry *old_tle = (TargetEntry *) lfirst(temp);
857 : :
7699 858 [ + + ]: 99150 : if (!old_tle->resjunk)
859 : : {
860 : : /* Normal attr: stash it into new_tles[] */
861 : 99063 : attrno = old_tle->resno;
7710 862 [ + - - + ]: 99063 : if (attrno < 1 || attrno > numattrs)
7710 tgl@sss.pgh.pa.us 863 [ # # ]:UBC 0 : elog(ERROR, "bogus resno %d in targetlist", attrno);
3180 andres@anarazel.de 864 :CBC 99063 : att_tup = TupleDescAttr(target_relation->rd_att, attrno - 1);
865 : :
866 : : /* We can (and must) ignore deleted attributes */
7710 tgl@sss.pgh.pa.us 867 [ - + ]: 99063 : if (att_tup->attisdropped)
7710 tgl@sss.pgh.pa.us 868 :UBC 0 : continue;
869 : :
870 : : /* Merge with any prior assignment to same attribute */
7710 tgl@sss.pgh.pa.us 871 :CBC 99051 : new_tles[attrno - 1] =
872 : 99063 : process_matched_tle(old_tle,
873 : 99063 : new_tles[attrno - 1],
874 : 99063 : NameStr(att_tup->attname));
875 : : }
876 : : else
877 : : {
878 : : /*
879 : : * Copy all resjunk tlist entries to junk_tlist, and assign them
880 : : * resnos above the last real resno.
881 : : *
882 : : * Typical junk entries include ORDER BY or GROUP BY expressions
883 : : * (are these actually possible in an INSERT or UPDATE?), system
884 : : * attribute references, etc.
885 : : */
886 : :
887 : : /* Get the resno right, but don't copy unnecessarily */
7699 888 [ - + ]: 87 : if (old_tle->resno != next_junk_attrno)
889 : : {
7699 tgl@sss.pgh.pa.us 890 :UBC 0 : old_tle = flatCopyTargetEntry(old_tle);
891 : 0 : old_tle->resno = next_junk_attrno;
892 : : }
7710 tgl@sss.pgh.pa.us 893 :CBC 87 : junk_tlist = lappend(junk_tlist, old_tle);
894 : 87 : next_junk_attrno++;
895 : : }
896 : : }
897 : :
898 [ + + ]: 240230 : for (attrno = 1; attrno <= numattrs; attrno++)
899 : : {
900 : 185780 : TargetEntry *new_tle = new_tles[attrno - 1];
901 : : bool apply_default;
902 : :
3180 andres@anarazel.de 903 : 185780 : att_tup = TupleDescAttr(target_relation->rd_att, attrno - 1);
904 : :
905 : : /* We can (and must) ignore deleted attributes */
7710 tgl@sss.pgh.pa.us 906 [ + + ]: 185780 : if (att_tup->attisdropped)
907 : 668 : continue;
908 : :
909 : : /*
910 : : * Handle the two cases where we need to insert a default expression:
911 : : * it's an INSERT and there's no tlist entry for the column, or the
912 : : * tlist entry is a DEFAULT placeholder node.
913 : : */
3316 peter_e@gmx.net 914 [ + + + + : 283902 : apply_default = ((new_tle == NULL && commandType == CMD_INSERT) ||
+ + ]
3240 tgl@sss.pgh.pa.us 915 [ + - + + ]: 98790 : (new_tle && new_tle->expr && IsA(new_tle->expr, SetToDefault)));
916 : :
3316 peter_e@gmx.net 917 [ + + ]: 185112 : if (commandType == CMD_INSERT)
918 : : {
1990 tgl@sss.pgh.pa.us 919 : 99181 : int values_attrno = 0;
920 : :
921 : : /* Source attribute number for values that come from a VALUES RTE */
922 [ + + + + : 99181 : if (values_rte && new_tle && IsA(new_tle->expr, Var))
+ + ]
923 : : {
924 : 6378 : Var *var = (Var *) new_tle->expr;
925 : :
926 [ + - ]: 6378 : if (var->varno == values_rte_index)
927 : 6378 : values_attrno = var->varattno;
928 : : }
929 : :
930 : : /*
931 : : * Can only insert DEFAULT into GENERATED ALWAYS identity columns,
932 : : * unless either OVERRIDING USER VALUE or OVERRIDING SYSTEM VALUE
933 : : * is specified.
934 : : */
3316 peter_e@gmx.net 935 [ + + + + ]: 99181 : if (att_tup->attidentity == ATTRIBUTE_IDENTITY_ALWAYS && !apply_default)
936 : : {
2226 peter@eisentraut.org 937 [ + + ]: 94 : if (override == OVERRIDING_USER_VALUE)
938 : 28 : apply_default = true;
939 [ + + ]: 66 : else if (override != OVERRIDING_SYSTEM_VALUE)
940 : : {
941 : : /*
942 : : * If this column's values come from a VALUES RTE, test
943 : : * whether it contains only SetToDefault items. Since the
944 : : * VALUES list might be quite large, we arrange to only
945 : : * scan it once.
946 : : */
1990 tgl@sss.pgh.pa.us 947 [ + + ]: 34 : if (values_attrno != 0)
948 : : {
949 [ + - ]: 18 : if (default_only_cols == NULL)
950 : 18 : default_only_cols = findDefaultOnlyColumns(values_rte);
951 : :
952 [ + + ]: 18 : if (bms_is_member(values_attrno, default_only_cols))
953 : 6 : apply_default = true;
954 : : }
955 : :
956 [ + + ]: 34 : if (!apply_default)
957 [ + - ]: 28 : ereport(ERROR,
958 : : (errcode(ERRCODE_GENERATED_ALWAYS),
959 : : errmsg("cannot insert a non-DEFAULT value into column \"%s\"",
960 : : NameStr(att_tup->attname)),
961 : : errdetail("Column \"%s\" is an identity column defined as GENERATED ALWAYS.",
962 : : NameStr(att_tup->attname)),
963 : : errhint("Use OVERRIDING SYSTEM VALUE to override.")));
964 : : }
965 : : }
966 : :
967 : : /*
968 : : * Although inserting into a GENERATED BY DEFAULT identity column
969 : : * is allowed, apply the default if OVERRIDING USER VALUE is
970 : : * specified.
971 : : */
972 [ + + + + ]: 99153 : if (att_tup->attidentity == ATTRIBUTE_IDENTITY_BY_DEFAULT &&
973 : : override == OVERRIDING_USER_VALUE)
3316 peter_e@gmx.net 974 : 12 : apply_default = true;
975 : :
976 : : /*
977 : : * Can only insert DEFAULT into generated columns. (The
978 : : * OVERRIDING clause does not apply to generated columns, so we
979 : : * don't consider it here.)
980 : : */
2593 peter@eisentraut.org 981 [ + + + + ]: 99153 : if (att_tup->attgenerated && !apply_default)
982 : : {
983 : : /*
984 : : * If this column's values come from a VALUES RTE, test
985 : : * whether it contains only SetToDefault items, as above.
986 : : */
1990 tgl@sss.pgh.pa.us 987 [ + + ]: 117 : if (values_attrno != 0)
988 : : {
989 [ + - ]: 81 : if (default_only_cols == NULL)
990 : 81 : default_only_cols = findDefaultOnlyColumns(values_rte);
991 : :
992 [ + + ]: 81 : if (bms_is_member(values_attrno, default_only_cols))
993 : 25 : apply_default = true;
994 : : }
995 : :
996 [ + + ]: 117 : if (!apply_default)
997 [ + - ]: 92 : ereport(ERROR,
998 : : (errcode(ERRCODE_GENERATED_ALWAYS),
999 : : errmsg("cannot insert a non-DEFAULT value into column \"%s\"",
1000 : : NameStr(att_tup->attname)),
1001 : : errdetail("Column \"%s\" is a generated column.",
1002 : : NameStr(att_tup->attname))));
1003 : : }
1004 : :
1005 : : /*
1006 : : * For an INSERT from a VALUES RTE, return the attribute numbers
1007 : : * of any VALUES columns that will no longer be used (due to the
1008 : : * targetlist entry being replaced by a default expression).
1009 : : */
1010 [ + + + + : 99061 : if (values_attrno != 0 && apply_default && unused_values_attrnos)
+ - ]
1011 : 47 : *unused_values_attrnos = bms_add_member(*unused_values_attrnos,
1012 : : values_attrno);
1013 : : }
1014 : :
1015 : : /*
1016 : : * Updates to identity and generated columns follow the same rules as
1017 : : * above, except that UPDATE doesn't admit OVERRIDING clauses. Also,
1018 : : * the source can't be a VALUES RTE, so we needn't consider that.
1019 : : */
3316 peter_e@gmx.net 1020 [ + + ]: 184992 : if (commandType == CMD_UPDATE)
1021 : : {
1989 tgl@sss.pgh.pa.us 1022 [ + + + - ]: 85931 : if (att_tup->attidentity == ATTRIBUTE_IDENTITY_ALWAYS &&
1023 [ + + ]: 8 : new_tle && !apply_default)
3316 peter_e@gmx.net 1024 [ + - ]: 4 : ereport(ERROR,
1025 : : (errcode(ERRCODE_GENERATED_ALWAYS),
1026 : : errmsg("column \"%s\" can only be updated to DEFAULT",
1027 : : NameStr(att_tup->attname)),
1028 : : errdetail("Column \"%s\" is an identity column defined as GENERATED ALWAYS.",
1029 : : NameStr(att_tup->attname))));
1030 : :
2593 peter@eisentraut.org 1031 [ + + + + : 85927 : if (att_tup->attgenerated && new_tle && !apply_default)
+ + ]
1032 [ + - ]: 8 : ereport(ERROR,
1033 : : (errcode(ERRCODE_GENERATED_ALWAYS),
1034 : : errmsg("column \"%s\" can only be updated to DEFAULT",
1035 : : NameStr(att_tup->attname)),
1036 : : errdetail("Column \"%s\" is a generated column.",
1037 : : NameStr(att_tup->attname))));
1038 : : }
1039 : :
1040 [ + + ]: 184980 : if (att_tup->attgenerated)
1041 : : {
1042 : : /*
1043 : : * virtual generated column stores a null value; stored generated
1044 : : * column will be fixed in executor
1045 : : */
1046 : 1195 : new_tle = NULL;
1047 : : }
1048 [ + + ]: 183785 : else if (apply_default)
1049 : : {
1050 : : Node *new_expr;
1051 : :
3014 peter_e@gmx.net 1052 : 15355 : new_expr = build_column_default(target_relation, attrno);
1053 : :
1054 : : /*
1055 : : * If there is no default (ie, default is effectively NULL), we
1056 : : * can omit the tlist entry in the INSERT case, since the planner
1057 : : * can insert a NULL for itself, and there's no point in spending
1058 : : * any more rewriter cycles on the entry. But in the UPDATE case
1059 : : * we've got to explicitly set the column to NULL.
1060 : : */
8342 tgl@sss.pgh.pa.us 1061 [ + + ]: 15355 : if (!new_expr)
1062 : : {
1063 [ + + ]: 11646 : if (commandType == CMD_INSERT)
1064 : 11633 : new_tle = NULL;
1065 : : else
461 1066 : 13 : new_expr = coerce_null_to_domain(att_tup->atttypid,
1067 : : att_tup->atttypmod,
1068 : : att_tup->attcollation,
1069 : 13 : att_tup->attlen,
1070 : 13 : att_tup->attbyval);
1071 : : }
1072 : :
8796 1073 [ + + ]: 15355 : if (new_expr)
7699 1074 : 3722 : new_tle = makeTargetEntry((Expr *) new_expr,
1075 : : attrno,
1076 : 3722 : pstrdup(NameStr(att_tup->attname)),
1077 : : false);
1078 : : }
1079 : :
8796 1080 [ + + ]: 184980 : if (new_tle)
1081 : 101851 : new_tlist = lappend(new_tlist, new_tle);
1082 : : }
1083 : :
7710 1084 : 54450 : pfree(new_tles);
1085 : :
4015 andres@anarazel.de 1086 : 54450 : return list_concat(new_tlist, junk_tlist);
1087 : : }
1088 : :
1089 : :
1090 : : /*
1091 : : * Convert a matched TLE from the original tlist into a correct new TLE.
1092 : : *
1093 : : * This routine detects and handles multiple assignments to the same target
1094 : : * attribute. (The attribute name is needed only for error messages.)
1095 : : */
1096 : : static TargetEntry *
8796 tgl@sss.pgh.pa.us 1097 : 99063 : process_matched_tle(TargetEntry *src_tle,
1098 : : TargetEntry *prior_tle,
1099 : : const char *attrName)
1100 : : {
1101 : : TargetEntry *result;
3220 1102 : 99063 : CoerceToDomain *coerce_expr = NULL;
1103 : : Node *src_expr;
1104 : : Node *prior_expr;
1105 : : Node *src_input;
1106 : : Node *prior_input;
1107 : : Node *priorbottom;
1108 : : Node *newexpr;
1109 : :
8796 1110 [ + + ]: 99063 : if (prior_tle == NULL)
1111 : : {
1112 : : /*
1113 : : * Normal case where this is the first assignment to the attribute.
1114 : : */
1115 : 98838 : return src_tle;
1116 : : }
1117 : :
1118 : : /*----------
1119 : : * Multiple assignments to same attribute. Allow only if all are
1120 : : * FieldStore or SubscriptingRef assignment operations. This is a bit
1121 : : * tricky because what we may actually be looking at is a nest of
1122 : : * such nodes; consider
1123 : : * UPDATE tab SET col.fld1.subfld1 = x, col.fld2.subfld2 = y
1124 : : * The two expressions produced by the parser will look like
1125 : : * FieldStore(col, fld1, FieldStore(placeholder, subfld1, x))
1126 : : * FieldStore(col, fld2, FieldStore(placeholder, subfld2, y))
1127 : : * However, we can ignore the substructure and just consider the top
1128 : : * FieldStore or SubscriptingRef from each assignment, because it works to
1129 : : * combine these as
1130 : : * FieldStore(FieldStore(col, fld1,
1131 : : * FieldStore(placeholder, subfld1, x)),
1132 : : * fld2, FieldStore(placeholder, subfld2, y))
1133 : : * Note the leftmost expression goes on the inside so that the
1134 : : * assignments appear to occur left-to-right.
1135 : : *
1136 : : * For FieldStore, instead of nesting we can generate a single
1137 : : * FieldStore with multiple target fields. We must nest when
1138 : : * SubscriptingRefs are involved though.
1139 : : *
1140 : : * As a further complication, the destination column might be a domain,
1141 : : * resulting in each assignment containing a CoerceToDomain node over a
1142 : : * FieldStore or SubscriptingRef. These should have matching target
1143 : : * domains, so we strip them and reconstitute a single CoerceToDomain over
1144 : : * the combined FieldStore/SubscriptingRef nodes. (Notice that this has
1145 : : * the result that the domain's checks are applied only after we do all
1146 : : * the field or element updates, not after each one. This is desirable.)
1147 : : *----------
1148 : : */
8000 1149 : 225 : src_expr = (Node *) src_tle->expr;
1150 : 225 : prior_expr = (Node *) prior_tle->expr;
1151 : :
3220 1152 [ + - + + : 225 : if (src_expr && IsA(src_expr, CoerceToDomain) &&
+ - ]
1153 [ + - ]: 108 : prior_expr && IsA(prior_expr, CoerceToDomain) &&
1154 : 108 : ((CoerceToDomain *) src_expr)->resulttype ==
1155 [ + - ]: 108 : ((CoerceToDomain *) prior_expr)->resulttype)
1156 : : {
1157 : : /* we assume without checking that resulttypmod/resultcollid match */
1158 : 108 : coerce_expr = (CoerceToDomain *) src_expr;
1159 : 108 : src_expr = (Node *) ((CoerceToDomain *) src_expr)->arg;
1160 : 108 : prior_expr = (Node *) ((CoerceToDomain *) prior_expr)->arg;
1161 : : }
1162 : :
8000 1163 : 225 : src_input = get_assignment_input(src_expr);
1164 : 225 : prior_input = get_assignment_input(prior_expr);
1165 [ + + + - ]: 225 : if (src_input == NULL ||
1166 [ - + ]: 213 : prior_input == NULL ||
1167 : 213 : exprType(src_expr) != exprType(prior_expr))
8320 1168 [ + - ]: 12 : ereport(ERROR,
1169 : : (errcode(ERRCODE_SYNTAX_ERROR),
1170 : : errmsg("multiple assignments to same column \"%s\"",
1171 : : attrName)));
1172 : :
1173 : : /*
1174 : : * Prior TLE could be a nest of assignments if we do this more than once.
1175 : : */
8000 1176 : 213 : priorbottom = prior_input;
1177 : : for (;;)
1178 : 28 : {
7919 bruce@momjian.us 1179 : 241 : Node *newbottom = get_assignment_input(priorbottom);
1180 : :
8000 tgl@sss.pgh.pa.us 1181 [ + + ]: 241 : if (newbottom == NULL)
1182 : 213 : break; /* found the original Var reference */
1183 : 28 : priorbottom = newbottom;
1184 : : }
1185 [ - + ]: 213 : if (!equal(priorbottom, src_input))
8320 tgl@sss.pgh.pa.us 1186 [ # # ]:UBC 0 : ereport(ERROR,
1187 : : (errcode(ERRCODE_SYNTAX_ERROR),
1188 : : errmsg("multiple assignments to same column \"%s\"",
1189 : : attrName)));
1190 : :
1191 : : /*
1192 : : * Looks OK to nest 'em.
1193 : : */
8000 tgl@sss.pgh.pa.us 1194 [ + + ]:CBC 213 : if (IsA(src_expr, FieldStore))
1195 : : {
7919 bruce@momjian.us 1196 : 84 : FieldStore *fstore = makeNode(FieldStore);
1197 : :
8000 tgl@sss.pgh.pa.us 1198 [ + - ]: 84 : if (IsA(prior_expr, FieldStore))
1199 : : {
1200 : : /* combine the two */
1201 : 84 : memcpy(fstore, prior_expr, sizeof(FieldStore));
1202 : 84 : fstore->newvals =
2458 1203 : 84 : list_concat_copy(((FieldStore *) prior_expr)->newvals,
1204 : 84 : ((FieldStore *) src_expr)->newvals);
8000 1205 : 84 : fstore->fieldnums =
2458 1206 : 84 : list_concat_copy(((FieldStore *) prior_expr)->fieldnums,
1207 : 84 : ((FieldStore *) src_expr)->fieldnums);
1208 : : }
1209 : : else
1210 : : {
1211 : : /* general case, just nest 'em */
8000 tgl@sss.pgh.pa.us 1212 :UBC 0 : memcpy(fstore, src_expr, sizeof(FieldStore));
1213 : 0 : fstore->arg = (Expr *) prior_expr;
1214 : : }
8000 tgl@sss.pgh.pa.us 1215 :CBC 84 : newexpr = (Node *) fstore;
1216 : : }
2650 alvherre@alvh.no-ip. 1217 [ + - ]: 129 : else if (IsA(src_expr, SubscriptingRef))
1218 : : {
1219 : 129 : SubscriptingRef *sbsref = makeNode(SubscriptingRef);
1220 : :
1221 : 129 : memcpy(sbsref, src_expr, sizeof(SubscriptingRef));
1222 : 129 : sbsref->refexpr = (Expr *) prior_expr;
1223 : 129 : newexpr = (Node *) sbsref;
1224 : : }
1225 : : else
1226 : : {
7033 bruce@momjian.us 1227 [ # # ]:UBC 0 : elog(ERROR, "cannot happen");
1228 : : newexpr = NULL;
1229 : : }
1230 : :
3220 tgl@sss.pgh.pa.us 1231 [ + + ]:CBC 213 : if (coerce_expr)
1232 : : {
1233 : : /* put back the CoerceToDomain */
1234 : 108 : CoerceToDomain *newcoerce = makeNode(CoerceToDomain);
1235 : :
1236 : 108 : memcpy(newcoerce, coerce_expr, sizeof(CoerceToDomain));
1237 : 108 : newcoerce->arg = (Expr *) newexpr;
1238 : 108 : newexpr = (Node *) newcoerce;
1239 : : }
1240 : :
7699 1241 : 213 : result = flatCopyTargetEntry(src_tle);
1242 : 213 : result->expr = (Expr *) newexpr;
1243 : 213 : return result;
1244 : : }
1245 : :
1246 : : /*
1247 : : * If node is an assignment node, return its input; else return NULL
1248 : : */
1249 : : static Node *
8000 1250 : 691 : get_assignment_input(Node *node)
1251 : : {
1252 [ - + ]: 691 : if (node == NULL)
8000 tgl@sss.pgh.pa.us 1253 :UBC 0 : return NULL;
8000 tgl@sss.pgh.pa.us 1254 [ + + ]:CBC 691 : if (IsA(node, FieldStore))
1255 : : {
1256 : 168 : FieldStore *fstore = (FieldStore *) node;
1257 : :
1258 : 168 : return (Node *) fstore->arg;
1259 : : }
2650 alvherre@alvh.no-ip. 1260 [ + + ]: 523 : else if (IsA(node, SubscriptingRef))
1261 : : {
1262 : 286 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1263 : :
1264 [ - + ]: 286 : if (sbsref->refassgnexpr == NULL)
8000 tgl@sss.pgh.pa.us 1265 :UBC 0 : return NULL;
1266 : :
2650 alvherre@alvh.no-ip. 1267 :CBC 286 : return (Node *) sbsref->refexpr;
1268 : : }
1269 : :
8000 tgl@sss.pgh.pa.us 1270 : 237 : return NULL;
1271 : : }
1272 : :
1273 : : /*
1274 : : * Make an expression tree for the default value for a column.
1275 : : *
1276 : : * If there is no default, return a NULL instead.
1277 : : */
1278 : : Node *
8796 1279 : 99161 : build_column_default(Relation rel, int attrno)
1280 : : {
1281 : 99161 : TupleDesc rd_att = rel->rd_att;
3180 andres@anarazel.de 1282 : 99161 : Form_pg_attribute att_tup = TupleDescAttr(rd_att, attrno - 1);
8796 tgl@sss.pgh.pa.us 1283 : 99161 : Oid atttype = att_tup->atttypid;
1284 : 99161 : int32 atttypmod = att_tup->atttypmod;
1285 : 99161 : Node *expr = NULL;
1286 : : Oid exprtype;
1287 : :
3014 peter_e@gmx.net 1288 [ + + ]: 99161 : if (att_tup->attidentity)
1289 : : {
1290 : 335 : NextValueExpr *nve = makeNode(NextValueExpr);
1291 : :
728 peter@eisentraut.org 1292 : 335 : nve->seqid = getIdentitySequence(rel, attrno, false);
3014 peter_e@gmx.net 1293 : 335 : nve->typeId = att_tup->atttypid;
1294 : :
1295 : 335 : return (Node *) nve;
1296 : : }
1297 : :
1298 : : /*
1299 : : * If relation has a default for this column, fetch that expression.
1300 : : */
1855 tgl@sss.pgh.pa.us 1301 [ + + ]: 98826 : if (att_tup->atthasdef)
1302 : : {
951 peter@eisentraut.org 1303 : 77436 : expr = TupleDescGetDefault(rd_att, attrno);
1855 tgl@sss.pgh.pa.us 1304 [ - + ]: 77436 : if (expr == NULL)
1855 tgl@sss.pgh.pa.us 1305 [ # # ]:UBC 0 : elog(ERROR, "default expression not found for attribute %d of relation \"%s\"",
1306 : : attrno, RelationGetRelationName(rel));
1307 : : }
1308 : :
1309 : : /*
1310 : : * No per-column default, so look for a default for the type itself. But
1311 : : * not for generated columns.
1312 : : */
2593 peter@eisentraut.org 1313 [ + + + - ]:CBC 98826 : if (expr == NULL && !att_tup->attgenerated)
8069 tgl@sss.pgh.pa.us 1314 : 21390 : expr = get_typdefault(atttype);
1315 : :
8796 1316 [ + + ]: 98826 : if (expr == NULL)
1317 : 21225 : return NULL; /* No default anywhere */
1318 : :
1319 : : /*
1320 : : * Make sure the value is coerced to the target column type; this will
1321 : : * generally be true already, but there seem to be some corner cases
1322 : : * involving domain defaults where it might not be true. This should match
1323 : : * the parser's processing of non-defaulted expressions --- see
1324 : : * transformAssignedExpr().
1325 : : */
1326 : 77601 : exprtype = exprType(expr);
1327 : :
8310 bruce@momjian.us 1328 : 77601 : expr = coerce_to_target_type(NULL, /* no UNKNOWN params here */
1329 : : expr, exprtype,
1330 : : atttype, atttypmod,
1331 : : COERCION_ASSIGNMENT,
1332 : : COERCE_IMPLICIT_CAST,
1333 : : -1);
8630 tgl@sss.pgh.pa.us 1334 [ - + ]: 77601 : if (expr == NULL)
8320 tgl@sss.pgh.pa.us 1335 [ # # ]:UBC 0 : ereport(ERROR,
1336 : : (errcode(ERRCODE_DATATYPE_MISMATCH),
1337 : : errmsg("column \"%s\" is of type %s"
1338 : : " but default expression is of type %s",
1339 : : NameStr(att_tup->attname),
1340 : : format_type_be(atttype),
1341 : : format_type_be(exprtype)),
1342 : : errhint("You will need to rewrite or cast the expression.")));
1343 : :
8796 tgl@sss.pgh.pa.us 1344 :CBC 77601 : return expr;
1345 : : }
1346 : :
1347 : :
1348 : : /* Does VALUES RTE contain any SetToDefault items? */
1349 : : static bool
7216 mail@joeconway.com 1350 : 3312 : searchForDefault(RangeTblEntry *rte)
1351 : : {
1352 : : ListCell *lc;
1353 : :
1354 [ + - + + : 14259 : foreach(lc, rte->values_lists)
+ + ]
1355 : : {
7153 bruce@momjian.us 1356 : 11154 : List *sublist = (List *) lfirst(lc);
1357 : : ListCell *lc2;
1358 : :
7216 mail@joeconway.com 1359 [ + - + + : 35081 : foreach(lc2, sublist)
+ + ]
1360 : : {
7153 bruce@momjian.us 1361 : 24134 : Node *col = (Node *) lfirst(lc2);
1362 : :
7216 mail@joeconway.com 1363 [ + + ]: 24134 : if (IsA(col, SetToDefault))
1364 : 207 : return true;
1365 : : }
1366 : : }
1367 : 3105 : return false;
1368 : : }
1369 : :
1370 : :
1371 : : /*
1372 : : * Search a VALUES RTE for columns that contain only SetToDefault items,
1373 : : * returning a Bitmapset containing the attribute numbers of any such columns.
1374 : : */
1375 : : static Bitmapset *
1990 tgl@sss.pgh.pa.us 1376 : 99 : findDefaultOnlyColumns(RangeTblEntry *rte)
1377 : : {
1378 : 99 : Bitmapset *default_only_cols = NULL;
1379 : : ListCell *lc;
1380 : :
1381 [ + - + + : 189 : foreach(lc, rte->values_lists)
+ + ]
1382 : : {
1383 : 158 : List *sublist = (List *) lfirst(lc);
1384 : : ListCell *lc2;
1385 : : int i;
1386 : :
1387 [ + + ]: 158 : if (default_only_cols == NULL)
1388 : : {
1389 : : /* Populate the initial result bitmap from the first row */
1390 : 99 : i = 0;
1391 [ + - + + : 305 : foreach(lc2, sublist)
+ + ]
1392 : : {
1393 : 206 : Node *col = (Node *) lfirst(lc2);
1394 : :
1395 : 206 : i++;
1396 [ + + ]: 206 : if (IsA(col, SetToDefault))
1397 : 52 : default_only_cols = bms_add_member(default_only_cols, i);
1398 : : }
1399 : : }
1400 : : else
1401 : : {
1402 : : /* Update the result bitmap from this next row */
1403 : 59 : i = 0;
1404 [ + - + + : 193 : foreach(lc2, sublist)
+ + ]
1405 : : {
1406 : 134 : Node *col = (Node *) lfirst(lc2);
1407 : :
1408 : 134 : i++;
1409 [ + + ]: 134 : if (!IsA(col, SetToDefault))
1410 : 94 : default_only_cols = bms_del_member(default_only_cols, i);
1411 : : }
1412 : : }
1413 : :
1414 : : /*
1415 : : * If no column in the rows read so far contains only DEFAULT items,
1416 : : * we are done.
1417 : : */
1418 [ + + ]: 158 : if (bms_is_empty(default_only_cols))
1419 : 68 : break;
1420 : : }
1421 : :
1422 : 99 : return default_only_cols;
1423 : : }
1424 : :
1425 : :
1426 : : /*
1427 : : * When processing INSERT ... VALUES with a VALUES RTE (ie, multiple VALUES
1428 : : * lists), we have to replace any DEFAULT items in the VALUES lists with
1429 : : * the appropriate default expressions. The other aspects of targetlist
1430 : : * rewriting need be applied only to the query's targetlist proper.
1431 : : *
1432 : : * For an auto-updatable view, each DEFAULT item in the VALUES list is
1433 : : * replaced with the default from the view, if it has one. Otherwise it is
1434 : : * left untouched so that the underlying base relation's default can be
1435 : : * applied instead (when we later recurse to here after rewriting the query
1436 : : * to refer to the base relation instead of the view).
1437 : : *
1438 : : * For other types of relation, including rule- and trigger-updatable views,
1439 : : * all DEFAULT items are replaced, and if the target relation doesn't have a
1440 : : * default, the value is explicitly set to NULL.
1441 : : *
1442 : : * Also, if a DEFAULT item is found in a column mentioned in unused_cols,
1443 : : * it is explicitly set to NULL. This happens for columns in the VALUES RTE
1444 : : * whose corresponding targetlist entries have already been replaced with the
1445 : : * relation's default expressions, so that any values in those columns of the
1446 : : * VALUES RTE are no longer used. This can happen for identity and generated
1447 : : * columns (if INSERT ... OVERRIDING USER VALUE is used, or all the values to
1448 : : * be inserted are DEFAULT). In principle we could replace all entries in
1449 : : * such a column with NULL, whether DEFAULT or not; but it doesn't seem worth
1450 : : * the trouble.
1451 : : *
1452 : : * Note that we may have subscripted or field assignment targetlist entries,
1453 : : * as well as more complex expressions from already-replaced DEFAULT items if
1454 : : * we have recursed to here for an auto-updatable view. However, it ought to
1455 : : * be impossible for such entries to have DEFAULTs assigned to them, except
1456 : : * for unused columns, as described above --- we should only have to replace
1457 : : * DEFAULT items for targetlist entries that contain simple Vars referencing
1458 : : * the VALUES RTE, or which are no longer referred to by the targetlist.
1459 : : *
1460 : : * Returns true if all DEFAULT items were replaced, and false if some were
1461 : : * left untouched.
1462 : : */
1463 : : static bool
2620 dean.a.rasheed@gmail 1464 : 3312 : rewriteValuesRTE(Query *parsetree, RangeTblEntry *rte, int rti,
1465 : : Relation target_relation,
1466 : : Bitmapset *unused_cols)
1467 : : {
1468 : : List *newValues;
1469 : : ListCell *lc;
1470 : : bool isAutoUpdatableView;
1471 : : bool allReplaced;
1472 : : int numattrs;
1473 : : int *attrnos;
1474 : :
1475 : : /* Steps below are not sensible for non-INSERT queries */
1302 tgl@sss.pgh.pa.us 1476 [ - + ]: 3312 : Assert(parsetree->commandType == CMD_INSERT);
1477 [ - + ]: 3312 : Assert(rte->rtekind == RTE_VALUES);
1478 : :
1479 : : /*
1480 : : * Rebuilding all the lists is a pretty expensive proposition in a big
1481 : : * VALUES list, and it's a waste of time if there aren't any DEFAULT
1482 : : * placeholders. So first scan to see if there are any.
1483 : : */
1484 [ + + ]: 3312 : if (!searchForDefault(rte))
2631 dean.a.rasheed@gmail 1485 : 3105 : return true; /* nothing to do */
1486 : :
1487 : : /*
1488 : : * Scan the targetlist for entries referring to the VALUES RTE, and note
1489 : : * the target attributes. As noted above, we should only need to do this
1490 : : * for targetlist entries containing simple Vars --- nothing else in the
1491 : : * VALUES RTE should contain DEFAULT items (except possibly for unused
1492 : : * columns), and we complain if such a thing does occur.
1493 : : */
2620 1494 : 207 : numattrs = list_length(linitial(rte->values_lists));
1495 : 207 : attrnos = (int *) palloc0(numattrs * sizeof(int));
1496 : :
1497 [ + - + + : 832 : foreach(lc, parsetree->targetList)
+ + ]
1498 : : {
1499 : 625 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
1500 : :
1501 [ + + ]: 625 : if (IsA(tle->expr, Var))
1502 : : {
1503 : 535 : Var *var = (Var *) tle->expr;
1504 : :
1505 [ + - ]: 535 : if (var->varno == rti)
1506 : : {
1507 : 535 : int attrno = var->varattno;
1508 : :
1509 [ + - - + ]: 535 : Assert(attrno >= 1 && attrno <= numattrs);
1510 : 535 : attrnos[attrno - 1] = tle->resno;
1511 : : }
1512 : : }
1513 : : }
1514 : :
1515 : : /*
1516 : : * Check if the target relation is an auto-updatable view, in which case
1517 : : * unresolved defaults will be left untouched rather than being set to
1518 : : * NULL.
1519 : : */
2631 1520 : 207 : isAutoUpdatableView = false;
1302 tgl@sss.pgh.pa.us 1521 [ + + ]: 207 : if (target_relation->rd_rel->relkind == RELKIND_VIEW &&
796 dean.a.rasheed@gmail 1522 [ + + ]: 76 : !view_has_instead_trigger(target_relation, CMD_INSERT, NIL))
1523 : : {
1524 : : List *locks;
1525 : : bool hasUpdate;
1526 : : bool found;
1527 : : ListCell *l;
1528 : :
1529 : : /* Look for an unconditional DO INSTEAD rule */
1530 : 68 : locks = matchLocks(CMD_INSERT, target_relation,
1531 : : parsetree->resultRelation, parsetree, &hasUpdate);
1532 : :
2631 1533 : 68 : found = false;
1534 [ + + + + : 84 : foreach(l, locks)
+ + ]
1535 : : {
1536 : 24 : RewriteRule *rule_lock = (RewriteRule *) lfirst(l);
1537 : :
1538 [ + + ]: 24 : if (rule_lock->isInstead &&
1539 [ + - ]: 8 : rule_lock->qual == NULL)
1540 : : {
1541 : 8 : found = true;
1542 : 8 : break;
1543 : : }
1544 : : }
1545 : :
1546 : : /*
1547 : : * If we didn't find an unconditional DO INSTEAD rule, assume that the
1548 : : * view is auto-updatable. If it isn't, rewriteTargetView() will
1549 : : * throw an error.
1550 : : */
1551 [ + + ]: 68 : if (!found)
1552 : 60 : isAutoUpdatableView = true;
1553 : : }
1554 : :
7216 mail@joeconway.com 1555 : 207 : newValues = NIL;
2631 dean.a.rasheed@gmail 1556 : 207 : allReplaced = true;
7216 mail@joeconway.com 1557 [ + - + + : 637 : foreach(lc, rte->values_lists)
+ + ]
1558 : : {
7153 bruce@momjian.us 1559 : 430 : List *sublist = (List *) lfirst(lc);
1560 : 430 : List *newList = NIL;
1561 : : ListCell *lc2;
1562 : : int i;
1563 : :
2620 dean.a.rasheed@gmail 1564 [ - + ]: 430 : Assert(list_length(sublist) == numattrs);
1565 : :
1566 : 430 : i = 0;
1567 [ + - + + : 1710 : foreach(lc2, sublist)
+ + ]
1568 : : {
7153 bruce@momjian.us 1569 : 1280 : Node *col = (Node *) lfirst(lc2);
2620 dean.a.rasheed@gmail 1570 : 1280 : int attrno = attrnos[i++];
1571 : :
7216 mail@joeconway.com 1572 [ + + ]: 1280 : if (IsA(col, SetToDefault))
1573 : : {
1574 : : Form_pg_attribute att_tup;
1575 : : Node *new_expr;
1576 : :
1577 : : /*
1578 : : * If this column isn't used, just replace the DEFAULT with
1579 : : * NULL (attrno will be 0 in this case because the targetlist
1580 : : * entry will have been replaced by the default expression).
1581 : : */
1990 tgl@sss.pgh.pa.us 1582 [ + + ]: 592 : if (bms_is_member(i, unused_cols))
1583 : 86 : {
1584 : 86 : SetToDefault *def = (SetToDefault *) col;
1585 : :
1586 : 86 : newList = lappend(newList,
1587 : 86 : makeNullConst(def->typeId,
1588 : : def->typeMod,
1589 : : def->collation));
1590 : 86 : continue;
1591 : : }
1592 : :
2620 dean.a.rasheed@gmail 1593 [ - + ]: 506 : if (attrno == 0)
2620 dean.a.rasheed@gmail 1594 [ # # ]:UBC 0 : elog(ERROR, "cannot set value in column %d to DEFAULT", i);
1302 tgl@sss.pgh.pa.us 1595 [ + - - + ]:CBC 506 : Assert(attrno > 0 && attrno <= target_relation->rd_att->natts);
3180 andres@anarazel.de 1596 : 506 : att_tup = TupleDescAttr(target_relation->rd_att, attrno - 1);
1597 : :
1302 tgl@sss.pgh.pa.us 1598 [ + - ]: 506 : if (!att_tup->attisdropped)
7216 mail@joeconway.com 1599 : 506 : new_expr = build_column_default(target_relation, attrno);
1600 : : else
7153 bruce@momjian.us 1601 :UBC 0 : new_expr = NULL; /* force a NULL if dropped */
1602 : :
1603 : : /*
1604 : : * If there is no default (ie, default is effectively NULL),
1605 : : * we've got to explicitly set the column to NULL, unless the
1606 : : * target relation is an auto-updatable view.
1607 : : */
7216 mail@joeconway.com 1608 [ + + ]:CBC 506 : if (!new_expr)
1609 : : {
2631 dean.a.rasheed@gmail 1610 [ + + ]: 238 : if (isAutoUpdatableView)
1611 : : {
1612 : : /* Leave the value untouched */
1613 : 100 : newList = lappend(newList, col);
1614 : 100 : allReplaced = false;
1615 : 100 : continue;
1616 : : }
1617 : :
461 tgl@sss.pgh.pa.us 1618 : 138 : new_expr = coerce_null_to_domain(att_tup->atttypid,
1619 : : att_tup->atttypmod,
1620 : : att_tup->attcollation,
1621 : 138 : att_tup->attlen,
1622 : 138 : att_tup->attbyval);
1623 : : }
7216 mail@joeconway.com 1624 : 406 : newList = lappend(newList, new_expr);
1625 : : }
1626 : : else
1627 : 688 : newList = lappend(newList, col);
1628 : : }
1629 : 430 : newValues = lappend(newValues, newList);
1630 : : }
1631 : 207 : rte->values_lists = newValues;
1632 : :
2620 dean.a.rasheed@gmail 1633 : 207 : pfree(attrnos);
1634 : :
2631 1635 : 207 : return allReplaced;
1636 : : }
1637 : :
1638 : : /*
1639 : : * Mop up any remaining DEFAULT items in the given VALUES RTE by
1640 : : * replacing them with NULL constants.
1641 : : *
1642 : : * This is used for the product queries generated by DO ALSO rules attached to
1643 : : * an auto-updatable view. The action can't depend on the "target relation"
1644 : : * since the product query might not have one (it needn't be an INSERT).
1645 : : * Essentially, such queries are treated as being attached to a rule-updatable
1646 : : * view.
1647 : : */
1648 : : static void
1302 tgl@sss.pgh.pa.us 1649 : 16 : rewriteValuesRTEToNulls(Query *parsetree, RangeTblEntry *rte)
1650 : : {
1651 : : List *newValues;
1652 : : ListCell *lc;
1653 : :
1654 : 16 : newValues = NIL;
1655 [ + - + + : 48 : foreach(lc, rte->values_lists)
+ + ]
1656 : : {
1657 : 32 : List *sublist = (List *) lfirst(lc);
1658 : 32 : List *newList = NIL;
1659 : : ListCell *lc2;
1660 : :
1661 [ + - + + : 136 : foreach(lc2, sublist)
+ + ]
1662 : : {
1663 : 104 : Node *col = (Node *) lfirst(lc2);
1664 : :
1665 [ + + ]: 104 : if (IsA(col, SetToDefault))
1666 : : {
1667 : 44 : SetToDefault *def = (SetToDefault *) col;
1668 : :
1669 : 44 : newList = lappend(newList, makeNullConst(def->typeId,
1670 : : def->typeMod,
1671 : : def->collation));
1672 : : }
1673 : : else
1674 : 60 : newList = lappend(newList, col);
1675 : : }
1676 : 32 : newValues = lappend(newValues, newList);
1677 : : }
1678 : 16 : rte->values_lists = newValues;
1679 : 16 : }
1680 : :
1681 : :
1682 : : /*
1683 : : * matchLocks -
1684 : : * match a relation's list of locks and returns the matching rules
1685 : : */
1686 : : static List *
9349 1687 : 56612 : matchLocks(CmdType event,
1688 : : Relation relation,
1689 : : int varno,
1690 : : Query *parsetree,
1691 : : bool *hasUpdate)
1692 : : {
796 dean.a.rasheed@gmail 1693 : 56612 : RuleLock *rulelocks = relation->rd_rules;
8599 tgl@sss.pgh.pa.us 1694 : 56612 : List *matching_locks = NIL;
1695 : : int nlocks;
1696 : : int i;
1697 : :
8470 1698 [ + + ]: 56612 : if (rulelocks == NULL)
1699 : 52674 : return NIL;
1700 : :
9349 1701 [ + - ]: 3938 : if (parsetree->commandType != CMD_SELECT)
1702 : : {
1703 [ - + ]: 3938 : if (parsetree->resultRelation != varno)
9349 tgl@sss.pgh.pa.us 1704 :UBC 0 : return NIL;
1705 : : }
1706 : :
9349 tgl@sss.pgh.pa.us 1707 :CBC 3938 : nlocks = rulelocks->numLocks;
1708 : :
1709 [ + + ]: 9036 : for (i = 0; i < nlocks; i++)
1710 : : {
1711 : 5110 : RewriteRule *oneLock = rulelocks->rules[i];
1712 : :
4015 andres@anarazel.de 1713 [ + + ]: 5110 : if (oneLock->event == CMD_UPDATE)
1714 : 488 : *hasUpdate = true;
1715 : :
1716 : : /*
1717 : : * Suppress ON INSERT/UPDATE/DELETE rules that are disabled or
1718 : : * configured to not fire during the current session's replication
1719 : : * role. ON SELECT rules will always be applied in order to keep views
1720 : : * working even in LOCAL or REPLICA role.
1721 : : */
6987 JanWieck@Yahoo.com 1722 [ + + ]: 5110 : if (oneLock->event != CMD_SELECT)
1723 : : {
1724 [ + + ]: 1992 : if (SessionReplicationRole == SESSION_REPLICATION_ROLE_REPLICA)
1725 : : {
1726 [ + + ]: 8 : if (oneLock->enabled == RULE_FIRES_ON_ORIGIN ||
1727 [ - + ]: 4 : oneLock->enabled == RULE_DISABLED)
1728 : 4 : continue;
1729 : : }
1730 : : else /* ORIGIN or LOCAL ROLE */
1731 : : {
1732 [ + + ]: 1984 : if (oneLock->enabled == RULE_FIRES_ON_REPLICA ||
1733 [ + + ]: 1980 : oneLock->enabled == RULE_DISABLED)
1734 : 20 : continue;
1735 : : }
1736 : :
1737 : : /* Non-SELECT rules are not supported for MERGE */
796 dean.a.rasheed@gmail 1738 [ + + ]: 1968 : if (parsetree->commandType == CMD_MERGE)
1739 [ + - ]: 12 : ereport(ERROR,
1740 : : errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1741 : : errmsg("cannot execute MERGE on relation \"%s\"",
1742 : : RelationGetRelationName(relation)),
1743 : : errdetail("MERGE is not supported for relations with rules."));
1744 : : }
1745 : :
9349 tgl@sss.pgh.pa.us 1746 [ + + ]: 5074 : if (oneLock->event == event)
1747 : : {
1748 [ - + - - ]: 1124 : if (parsetree->commandType != CMD_SELECT ||
4625 kgrittn@postgresql.o 1749 :UBC 0 : rangeTableEntry_used((Node *) parsetree, varno, 0))
8599 tgl@sss.pgh.pa.us 1750 :CBC 1124 : matching_locks = lappend(matching_locks, oneLock);
1751 : : }
1752 : : }
1753 : :
1754 : 3926 : return matching_locks;
1755 : : }
1756 : :
1757 : :
1758 : : /*
1759 : : * ApplyRetrieveRule - expand an ON SELECT rule
1760 : : */
1761 : : static Query *
9349 1762 : 11049 : ApplyRetrieveRule(Query *parsetree,
1763 : : RewriteRule *rule,
1764 : : int rt_index,
1765 : : Relation relation,
1766 : : List *activeRIRs)
1767 : : {
1768 : : Query *rule_action;
1769 : : RangeTblEntry *rte;
1770 : : RowMarkClause *rc;
1771 : : int numCols;
1772 : :
8010 neilc@samurai.com 1773 [ - + ]: 11049 : if (list_length(rule->actions) != 1)
8320 tgl@sss.pgh.pa.us 1774 [ # # ]:UBC 0 : elog(ERROR, "expected just one rule action");
9349 tgl@sss.pgh.pa.us 1775 [ - + ]:CBC 11049 : if (rule->qual != NULL)
8320 tgl@sss.pgh.pa.us 1776 [ # # ]:UBC 0 : elog(ERROR, "cannot handle qualified ON SELECT rule");
1777 : :
1778 : : /* Check if the expansion of non-system views are restricted */
638 msawada@postgresql.o 1779 [ + + + + :CBC 11049 : if (unlikely((restrict_nonsystem_relation_kind & RESTRICT_RELKIND_VIEW) != 0 &&
+ + ]
1780 : : RelationGetRelid(relation) >= FirstNormalObjectId))
1781 [ + - ]: 4 : ereport(ERROR,
1782 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
1783 : : errmsg("access to non-system view \"%s\" is restricted",
1784 : : RelationGetRelationName(relation))));
1785 : :
5686 tgl@sss.pgh.pa.us 1786 [ + + ]: 11045 : if (rt_index == parsetree->resultRelation)
1787 : : {
1788 : : /*
1789 : : * We have a view as the result relation of the query, and it wasn't
1790 : : * rewritten by any rule. This case is supported if there is an
1791 : : * INSTEAD OF trigger that will trap attempts to insert/update/delete
1792 : : * view rows. The executor will check that; for the moment just plow
1793 : : * ahead. We have two cases:
1794 : : *
1795 : : * For INSERT, we needn't do anything. The unmodified RTE will serve
1796 : : * fine as the result relation.
1797 : : *
1798 : : * For UPDATE/DELETE/MERGE, we need to expand the view so as to have
1799 : : * source data for the operation. But we also need an unmodified RTE
1800 : : * to serve as the target. So, copy the RTE and add the copy to the
1801 : : * rangetable. Note that the copy does not get added to the jointree.
1802 : : * Also note that there's a hack in fireRIRrules to avoid calling this
1803 : : * function again when it arrives at the copied RTE.
1804 : : */
1805 [ + + ]: 269 : if (parsetree->commandType == CMD_INSERT)
1806 : 79 : return parsetree;
1807 [ + + ]: 190 : else if (parsetree->commandType == CMD_UPDATE ||
796 dean.a.rasheed@gmail 1808 [ + + ]: 87 : parsetree->commandType == CMD_DELETE ||
1809 [ + - ]: 52 : parsetree->commandType == CMD_MERGE)
5686 tgl@sss.pgh.pa.us 1810 : 190 : {
1811 : : RangeTblEntry *newrte;
1812 : : Var *var;
1813 : : TargetEntry *tle;
1814 : :
1815 : 190 : rte = rt_fetch(rt_index, parsetree->rtable);
1816 : 190 : newrte = copyObject(rte);
1817 : 190 : parsetree->rtable = lappend(parsetree->rtable, newrte);
1818 : 190 : parsetree->resultRelation = list_length(parsetree->rtable);
1819 : : /* parsetree->mergeTargetRelation unchanged (use expanded view) */
1820 : :
1821 : : /*
1822 : : * For the most part, Vars referencing the view should remain as
1823 : : * they are, meaning that they implicitly represent OLD values.
1824 : : * But in the RETURNING list if any, we want such Vars to
1825 : : * represent NEW values, so change them to reference the new RTE.
1826 : : *
1827 : : * Since ChangeVarNodes scribbles on the tree in-place, copy the
1828 : : * RETURNING list first for safety.
1829 : : */
1830 : 190 : parsetree->returningList = copyObject(parsetree->returningList);
1831 : 190 : ChangeVarNodes((Node *) parsetree->returningList, rt_index,
1832 : : parsetree->resultRelation, 0);
1833 : :
1834 : : /*
1835 : : * To allow the executor to compute the original view row to pass
1836 : : * to the INSTEAD OF trigger, we add a resjunk whole-row Var
1837 : : * referencing the original RTE. This will later get expanded
1838 : : * into a RowExpr computing all the OLD values of the view row.
1839 : : */
3081 1840 : 190 : var = makeWholeRowVar(rte, rt_index, 0, false);
1841 : 190 : tle = makeTargetEntry((Expr *) var,
1842 : 190 : list_length(parsetree->targetList) + 1,
1843 : : pstrdup("wholerow"),
1844 : : true);
1845 : :
1846 : 190 : parsetree->targetList = lappend(parsetree->targetList, tle);
1847 : :
1848 : : /* Now, continue with expanding the original view RTE */
1849 : : }
1850 : : else
5686 tgl@sss.pgh.pa.us 1851 [ # # ]:UBC 0 : elog(ERROR, "unrecognized commandType: %d",
1852 : : (int) parsetree->commandType);
1853 : : }
1854 : :
1855 : : /*
1856 : : * Check if there's a FOR [KEY] UPDATE/SHARE clause applying to this view.
1857 : : *
1858 : : * Note: we needn't explicitly consider any such clauses appearing in
1859 : : * ancestor query levels; their effects have already been pushed down to
1860 : : * here by markQueryForLocking, and will be reflected in "rc".
1861 : : */
6033 tgl@sss.pgh.pa.us 1862 :CBC 10966 : rc = get_parse_rowmark(parsetree, rt_index);
1863 : :
1864 : : /*
1865 : : * Make a modifiable copy of the view query, and acquire needed locks on
1866 : : * the relations it mentions. Force at least RowShareLock for all such
1867 : : * rels if there's a FOR [KEY] UPDATE/SHARE clause affecting this view.
1868 : : */
8014 neilc@samurai.com 1869 : 10966 : rule_action = copyObject(linitial(rule->actions));
1870 : :
2943 tgl@sss.pgh.pa.us 1871 : 10966 : AcquireRewriteLocks(rule_action, true, (rc != NULL));
1872 : :
1873 : : /*
1874 : : * If FOR [KEY] UPDATE/SHARE of view, mark all the contained tables as
1875 : : * implicit FOR [KEY] UPDATE/SHARE, the same as the parser would have done
1876 : : * if the view's subquery had been written out explicitly.
1877 : : */
1878 [ + + ]: 10966 : if (rc != NULL)
1879 : 64 : markQueryForLocking(rule_action, (Node *) rule_action->jointree,
1880 : : rc->strength, rc->waitPolicy, true);
1881 : :
1882 : : /*
1883 : : * Recursively expand any view references inside the view.
1884 : : */
1885 : 10966 : rule_action = fireRIRrules(rule_action, activeRIRs);
1886 : :
1887 : : /*
1888 : : * Make sure the query is marked as having row security if the view query
1889 : : * does.
1890 : : */
540 nathan@postgresql.or 1891 : 10946 : parsetree->hasRowSecurity |= rule_action->hasRowSecurity;
1892 : :
1893 : : /*
1894 : : * Now, plug the view query in as a subselect, converting the relation's
1895 : : * original RTE to a subquery RTE.
1896 : : */
9349 tgl@sss.pgh.pa.us 1897 : 10946 : rte = rt_fetch(rt_index, parsetree->rtable);
1898 : :
8820 1899 : 10946 : rte->rtekind = RTE_SUBQUERY;
9349 1900 : 10946 : rte->subquery = rule_action;
2786 1901 [ - + + + ]: 10946 : rte->security_barrier = RelationIsSecurityView(relation);
1902 : :
1903 : : /*
1904 : : * Clear fields that should not be set in a subquery RTE. Note that we
1905 : : * leave the relid, relkind, rellockmode, and perminfoindex fields set, so
1906 : : * that the view relation can be appropriately locked before execution and
1907 : : * its permissions checked.
1908 : : */
1203 1909 : 10946 : rte->tablesample = NULL;
1910 : 10946 : rte->inh = false; /* must not be set for a subquery */
1911 : :
1912 : : /*
1913 : : * Since we allow CREATE OR REPLACE VIEW to add columns to a view, the
1914 : : * rule_action might emit more columns than we expected when the current
1915 : : * query was parsed. Various places expect rte->eref->colnames to be
1916 : : * consistent with the non-junk output columns of the subquery, so patch
1917 : : * things up if necessary by adding some dummy column names.
1918 : : */
1155 1919 : 10946 : numCols = ExecCleanTargetListLength(rule_action->targetList);
1920 [ + + ]: 10958 : while (list_length(rte->eref->colnames) < numCols)
1921 : : {
1922 : 12 : rte->eref->colnames = lappend(rte->eref->colnames,
1923 : 12 : makeString(pstrdup("?column?")));
1924 : : }
1925 : :
9713 1926 : 10946 : return parsetree;
1927 : : }
1928 : :
1929 : : /*
1930 : : * Recursively mark all relations used by a view as FOR [KEY] UPDATE/SHARE.
1931 : : *
1932 : : * This may generate an invalid query, eg if some sub-query uses an
1933 : : * aggregate. We leave it to the planner to detect that.
1934 : : *
1935 : : * NB: this must agree with the parser's transformLockingClause() routine.
1936 : : * However, we used to have to avoid marking a view's OLD and NEW rels for
1937 : : * updating, which motivated scanning the jointree to determine which rels
1938 : : * are used. Possibly that could now be simplified into just scanning the
1939 : : * rangetable as the parser does.
1940 : : */
1941 : : static void
6033 1942 : 128 : markQueryForLocking(Query *qry, Node *jtnode,
1943 : : LockClauseStrength strength, LockWaitPolicy waitPolicy,
1944 : : bool pushedDown)
1945 : : {
7005 1946 [ - + ]: 128 : if (jtnode == NULL)
7005 tgl@sss.pgh.pa.us 1947 :UBC 0 : return;
7005 tgl@sss.pgh.pa.us 1948 [ + + ]:CBC 128 : if (IsA(jtnode, RangeTblRef))
1949 : : {
1950 : 64 : int rti = ((RangeTblRef *) jtnode)->rtindex;
1951 : 64 : RangeTblEntry *rte = rt_fetch(rti, qry->rtable);
1952 : :
8820 1953 [ + - ]: 64 : if (rte->rtekind == RTE_RELATION)
1954 : : {
1955 : : RTEPermissionInfo *perminfo;
1956 : :
4228 alvherre@alvh.no-ip. 1957 : 64 : applyLockingClause(qry, rti, strength, waitPolicy, pushedDown);
1958 : :
1246 1959 : 64 : perminfo = getRTEPermissionInfo(qry->rteperminfos, rte);
1960 : 64 : perminfo->requiredPerms |= ACL_SELECT_FOR_UPDATE;
1961 : : }
8820 tgl@sss.pgh.pa.us 1962 [ # # ]:UBC 0 : else if (rte->rtekind == RTE_SUBQUERY)
1963 : : {
4228 alvherre@alvh.no-ip. 1964 : 0 : applyLockingClause(qry, rti, strength, waitPolicy, pushedDown);
1965 : : /* FOR UPDATE/SHARE of subquery is propagated to subquery's rels */
7005 tgl@sss.pgh.pa.us 1966 : 0 : markQueryForLocking(rte->subquery, (Node *) rte->subquery->jointree,
1967 : : strength, waitPolicy, true);
1968 : : }
1969 : : /* other RTE types are unaffected by FOR UPDATE */
1970 : : }
7005 tgl@sss.pgh.pa.us 1971 [ + - ]:CBC 64 : else if (IsA(jtnode, FromExpr))
1972 : : {
1973 : 64 : FromExpr *f = (FromExpr *) jtnode;
1974 : : ListCell *l;
1975 : :
1976 [ + - + + : 128 : foreach(l, f->fromlist)
+ + ]
4228 alvherre@alvh.no-ip. 1977 : 64 : markQueryForLocking(qry, lfirst(l), strength, waitPolicy, pushedDown);
1978 : : }
7005 tgl@sss.pgh.pa.us 1979 [ # # ]:UBC 0 : else if (IsA(jtnode, JoinExpr))
1980 : : {
1981 : 0 : JoinExpr *j = (JoinExpr *) jtnode;
1982 : :
4228 alvherre@alvh.no-ip. 1983 : 0 : markQueryForLocking(qry, j->larg, strength, waitPolicy, pushedDown);
1984 : 0 : markQueryForLocking(qry, j->rarg, strength, waitPolicy, pushedDown);
1985 : : }
1986 : : else
7005 tgl@sss.pgh.pa.us 1987 [ # # ]: 0 : elog(ERROR, "unrecognized node type: %d",
1988 : : (int) nodeTag(jtnode));
1989 : : }
1990 : :
1991 : :
1992 : : /*
1993 : : * fireRIRonSubLink -
1994 : : * Apply fireRIRrules() to each SubLink (subselect in expression) found
1995 : : * in the given tree.
1996 : : *
1997 : : * NOTE: although this has the form of a walker, we cheat and modify the
1998 : : * SubLink nodes in-place. It is caller's responsibility to ensure that
1999 : : * no unwanted side-effects occur!
2000 : : *
2001 : : * This is unlike most of the other routines that recurse into subselects,
2002 : : * because we must take control at the SubLink node in order to replace
2003 : : * the SubLink's subselect link with the possibly-rewritten subquery.
2004 : : */
2005 : : static bool
540 nathan@postgresql.or 2006 :CBC 1986396 : fireRIRonSubLink(Node *node, fireRIRonSubLink_context *context)
2007 : : {
10077 bruce@momjian.us 2008 [ + + ]: 1986396 : if (node == NULL)
9713 tgl@sss.pgh.pa.us 2009 : 419604 : return false;
2010 [ + + ]: 1566792 : if (IsA(node, SubLink))
2011 : : {
2012 : 34097 : SubLink *sub = (SubLink *) node;
2013 : :
2014 : : /* Do what we came for */
8470 2015 : 34097 : sub->subselect = (Node *) fireRIRrules((Query *) sub->subselect,
2016 : : context->activeRIRs);
2017 : :
2018 : : /*
2019 : : * Remember if any of the sublinks have row security.
2020 : : */
540 nathan@postgresql.or 2021 : 34045 : context->hasRowSecurity |= ((Query *) sub->subselect)->hasRowSecurity;
2022 : :
2023 : : /* Fall through to process lefthand args of SubLink */
2024 : : }
2025 : :
2026 : : /*
2027 : : * Do NOT recurse into Query nodes, because fireRIRrules already processed
2028 : : * subselects of subselects for us.
2029 : : */
523 peter@eisentraut.org 2030 : 1566740 : return expression_tree_walker(node, fireRIRonSubLink, context);
2031 : : }
2032 : :
2033 : :
2034 : : /*
2035 : : * fireRIRrules -
2036 : : * Apply all RIR rules on each rangetable entry in the given query
2037 : : *
2038 : : * activeRIRs is a list of the OIDs of views we're already processing RIR
2039 : : * rules for, used to detect/reject recursion.
2040 : : */
2041 : : static Query *
2943 tgl@sss.pgh.pa.us 2042 : 374895 : fireRIRrules(Query *parsetree, List *activeRIRs)
2043 : : {
5686 2044 : 374895 : int origResultRelation = parsetree->resultRelation;
2045 : : int rt_index;
2046 : : ListCell *lc;
2047 : :
2048 : : /*
2049 : : * Expand SEARCH and CYCLE clauses in CTEs.
2050 : : *
2051 : : * This is just a convenient place to do this, since we are already
2052 : : * looking at each Query.
2053 : : */
1919 peter@eisentraut.org 2054 [ + + + + : 377542 : foreach(lc, parsetree->cteList)
+ + ]
2055 : : {
2056 : 2651 : CommonTableExpr *cte = lfirst_node(CommonTableExpr, lc);
2057 : :
2058 [ + + + + ]: 2651 : if (cte->search_clause || cte->cycle_clause)
2059 : : {
2060 : 96 : cte = rewriteSearchAndCycle(cte);
2061 : 92 : lfirst(lc) = cte;
2062 : : }
2063 : : }
2064 : :
2065 : : /*
2066 : : * don't try to convert this into a foreach loop, because rtable list can
2067 : : * get changed each time through...
2068 : : */
10077 bruce@momjian.us 2069 : 374891 : rt_index = 0;
8010 neilc@samurai.com 2070 [ + + ]: 848947 : while (rt_index < list_length(parsetree->rtable))
2071 : : {
2072 : : RangeTblEntry *rte;
2073 : : Relation rel;
2074 : : List *locks;
2075 : : RuleLock *rules;
2076 : : RewriteRule *rule;
2077 : : int i;
2078 : :
10077 bruce@momjian.us 2079 : 474144 : ++rt_index;
2080 : :
9682 tgl@sss.pgh.pa.us 2081 : 474144 : rte = rt_fetch(rt_index, parsetree->rtable);
2082 : :
2083 : : /*
2084 : : * Convert GRAPH_TABLE clause into a subquery using relational
2085 : : * operators. (This will change the rtekind to subquery, so it must
2086 : : * be done before the subquery handling below.)
2087 : : */
50 peter@eisentraut.org 2088 [ + + ]:GNC 474144 : if (rte->rtekind == RTE_GRAPH_TABLE)
2089 : : {
2090 : 485 : parsetree = rewriteGraphTable(parsetree, rt_index);
2091 : : }
2092 : :
2093 : : /*
2094 : : * A subquery RTE can't have associated rules, so there's nothing to
2095 : : * do to this level of the query, but we must recurse into the
2096 : : * subquery to expand any rule references in it.
2097 : : */
8820 tgl@sss.pgh.pa.us 2098 [ + + ]:CBC 474104 : if (rte->rtekind == RTE_SUBQUERY)
2099 : : {
2943 2100 : 39365 : rte->subquery = fireRIRrules(rte->subquery, activeRIRs);
2101 : :
2102 : : /*
2103 : : * While we are here, make sure the query is marked as having row
2104 : : * security if any of its subqueries do.
2105 : : */
540 nathan@postgresql.or 2106 : 39341 : parsetree->hasRowSecurity |= rte->subquery->hasRowSecurity;
2107 : :
9349 tgl@sss.pgh.pa.us 2108 : 39341 : continue;
2109 : : }
2110 : :
2111 : : /*
2112 : : * Joins and other non-relation RTEs can be ignored completely.
2113 : : */
8820 2114 [ + + ]: 434739 : if (rte->rtekind != RTE_RELATION)
2115 : 111380 : continue;
2116 : :
2117 : : /*
2118 : : * Always ignore RIR rules for materialized views referenced in
2119 : : * queries. (This does not prevent refreshing MVs, since they aren't
2120 : : * referenced in their own query definitions.)
2121 : : *
2122 : : * Note: in the future we might want to allow MVs to be conditionally
2123 : : * expanded as if they were regular views, if they are not scannable.
2124 : : * In that case this test would need to be postponed till after we've
2125 : : * opened the rel, so that we could check its state.
2126 : : */
4756 2127 [ + + ]: 323359 : if (rte->relkind == RELKIND_MATVIEW)
2128 : 291 : continue;
2129 : :
2130 : : /*
2131 : : * In INSERT ... ON CONFLICT, ignore the EXCLUDED pseudo-relation;
2132 : : * even if it points to a view, we needn't expand it, and should not
2133 : : * because we want the RTE to remain of RTE_RELATION type. Otherwise,
2134 : : * it would get changed to RTE_SUBQUERY type, which is an
2135 : : * untested/unsupported situation.
2136 : : */
2831 2137 [ + + ]: 323068 : if (parsetree->onConflict &&
2138 [ + + ]: 3142 : rt_index == parsetree->onConflict->exclRelIndex)
2139 : 1158 : continue;
2140 : :
2141 : : /*
2142 : : * If the table is not referenced in the query, then we ignore it.
2143 : : * This prevents infinite expansion loop due to new rtable entries
2144 : : * inserted by expansion of a rule. A table is referenced if it is
2145 : : * part of the join set (a source table), or is referenced by any Var
2146 : : * nodes, or is the result table.
2147 : : */
7646 2148 [ + + ]: 321910 : if (rt_index != parsetree->resultRelation &&
2149 [ + + ]: 268193 : !rangeTableEntry_used((Node *) parsetree, rt_index, 0))
10077 bruce@momjian.us 2150 : 5091 : continue;
2151 : :
2152 : : /*
2153 : : * Also, if this is a new result relation introduced by
2154 : : * ApplyRetrieveRule, we don't want to do anything more with it.
2155 : : */
5686 tgl@sss.pgh.pa.us 2156 [ + + + + ]: 316819 : if (rt_index == parsetree->resultRelation &&
2157 : : rt_index != origResultRelation)
2158 : 190 : continue;
2159 : :
2160 : : /*
2161 : : * We can use NoLock here since either the parser or
2162 : : * AcquireRewriteLocks should have locked the rel already.
2163 : : */
55 peter@eisentraut.org 2164 :GNC 316629 : rel = relation_open(rte->relid, NoLock);
2165 : :
2166 : : /*
2167 : : * Collect the RIR rules that we must apply
2168 : : */
9707 tgl@sss.pgh.pa.us 2169 :CBC 316629 : rules = rel->rd_rules;
4246 sfrost@snowman.net 2170 [ + + ]: 316629 : if (rules != NULL)
2171 : : {
2172 : 12052 : locks = NIL;
2173 [ + + ]: 26372 : for (i = 0; i < rules->numLocks; i++)
2174 : : {
2175 : 14320 : rule = rules->rules[i];
2176 [ + + ]: 14320 : if (rule->event != CMD_SELECT)
2177 : 3271 : continue;
2178 : :
2179 : 11049 : locks = lappend(locks, rule);
2180 : : }
2181 : :
2182 : : /*
2183 : : * If we found any, apply them --- but first check for recursion!
2184 : : */
2185 [ + + ]: 12052 : if (locks != NIL)
2186 : : {
2187 : : ListCell *l;
2188 : :
2189 [ - + ]: 11049 : if (list_member_oid(activeRIRs, RelationGetRelid(rel)))
4246 sfrost@snowman.net 2190 [ # # ]:UBC 0 : ereport(ERROR,
2191 : : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2192 : : errmsg("infinite recursion detected in rules for relation \"%s\"",
2193 : : RelationGetRelationName(rel))));
2484 tgl@sss.pgh.pa.us 2194 :CBC 11049 : activeRIRs = lappend_oid(activeRIRs, RelationGetRelid(rel));
2195 : :
4246 sfrost@snowman.net 2196 [ + - + + : 22074 : foreach(l, locks)
+ + ]
2197 : : {
2198 : 11049 : rule = lfirst(l);
2199 : :
2200 : 11049 : parsetree = ApplyRetrieveRule(parsetree,
2201 : : rule,
2202 : : rt_index,
2203 : : rel,
2204 : : activeRIRs);
2205 : : }
2206 : :
2484 tgl@sss.pgh.pa.us 2207 : 11025 : activeRIRs = list_delete_last(activeRIRs);
2208 : : }
2209 : : }
2210 : :
2661 andres@anarazel.de 2211 : 316605 : table_close(rel, NoLock);
2212 : : }
2213 : :
2214 : : /* Recurse into subqueries in WITH */
6422 tgl@sss.pgh.pa.us 2215 [ + + + + : 377450 : foreach(lc, parsetree->cteList)
+ + ]
2216 : : {
2217 : 2647 : CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
2218 : :
2219 : 2647 : cte->ctequery = (Node *)
2943 2220 : 2647 : fireRIRrules((Query *) cte->ctequery, activeRIRs);
2221 : :
2222 : : /*
2223 : : * While we are here, make sure the query is marked as having row
2224 : : * security if any of its CTEs do.
2225 : : */
540 nathan@postgresql.or 2226 : 2647 : parsetree->hasRowSecurity |= ((Query *) cte->ctequery)->hasRowSecurity;
2227 : : }
2228 : :
2229 : : /*
2230 : : * Recurse into sublink subqueries, too. But we already did the ones in
2231 : : * the rtable and cteList.
2232 : : */
9349 tgl@sss.pgh.pa.us 2233 [ + + ]: 374803 : if (parsetree->hasSubLinks)
2234 : : {
2235 : : fireRIRonSubLink_context context;
2236 : :
540 nathan@postgresql.or 2237 : 27402 : context.activeRIRs = activeRIRs;
2238 : 27402 : context.hasRowSecurity = false;
2239 : :
523 peter@eisentraut.org 2240 : 27402 : query_tree_walker(parsetree, fireRIRonSubLink, &context,
2241 : : QTW_IGNORE_RC_SUBQUERIES);
2242 : :
2243 : : /*
2244 : : * Make sure the query is marked as having row security if any of its
2245 : : * sublinks do.
2246 : : */
540 nathan@postgresql.or 2247 : 27402 : parsetree->hasRowSecurity |= context.hasRowSecurity;
2248 : : }
2249 : :
2250 : : /*
2251 : : * Apply any row-level security policies. We do this last because it
2252 : : * requires special recursion detection if the new quals have sublink
2253 : : * subqueries, and if we did it in the loop above query_tree_walker would
2254 : : * then recurse into those quals a second time.
2255 : : */
4031 sfrost@snowman.net 2256 : 374803 : rt_index = 0;
2257 [ + + + + : 848719 : foreach(lc, parsetree->rtable)
+ + ]
2258 : : {
2259 : 474056 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
2260 : : Relation rel;
2261 : : List *securityQuals;
2262 : : List *withCheckOptions;
2263 : : bool hasRowSecurity;
2264 : : bool hasSubLinks;
2265 : :
2266 : 474056 : ++rt_index;
2267 : :
2268 : : /* Only normal relations can have RLS policies */
434 rguo@postgresql.org 2269 [ + + ]: 474056 : if (rte->rtekind != RTE_RELATION ||
2270 [ + + ]: 312389 : (rte->relkind != RELKIND_RELATION &&
2271 [ + + ]: 17477 : rte->relkind != RELKIND_PARTITIONED_TABLE))
4031 sfrost@snowman.net 2272 : 167570 : continue;
2273 : :
55 peter@eisentraut.org 2274 :GNC 306486 : rel = relation_open(rte->relid, NoLock);
2275 : :
2276 : : /*
2277 : : * Fetch any new security quals that must be applied to this RTE.
2278 : : */
3885 sfrost@snowman.net 2279 :CBC 306486 : get_row_security_policies(parsetree, rte, rt_index,
2280 : : &securityQuals, &withCheckOptions,
2281 : : &hasRowSecurity, &hasSubLinks);
2282 : :
4031 2283 [ + + + + ]: 306430 : if (securityQuals != NIL || withCheckOptions != NIL)
2284 : : {
2285 [ + + ]: 2218 : if (hasSubLinks)
2286 : : {
2287 : : acquireLocksOnSubLinks_context context;
2288 : : fireRIRonSubLink_context fire_context;
2289 : :
2290 : : /*
2291 : : * Recursively process the new quals, checking for infinite
2292 : : * recursion.
2293 : : */
2294 [ + + ]: 536 : if (list_member_oid(activeRIRs, RelationGetRelid(rel)))
2295 [ + - ]: 32 : ereport(ERROR,
2296 : : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2297 : : errmsg("infinite recursion detected in policy for relation \"%s\"",
2298 : : RelationGetRelationName(rel))));
2299 : :
2484 tgl@sss.pgh.pa.us 2300 : 504 : activeRIRs = lappend_oid(activeRIRs, RelationGetRelid(rel));
2301 : :
2302 : : /*
2303 : : * get_row_security_policies just passed back securityQuals
2304 : : * and/or withCheckOptions, and there were SubLinks, make sure
2305 : : * we lock any relations which are referenced.
2306 : : *
2307 : : * These locks would normally be acquired by the parser, but
2308 : : * securityQuals and withCheckOptions are added post-parsing.
2309 : : */
3903 sfrost@snowman.net 2310 : 504 : context.for_execute = true;
2311 : 504 : (void) acquireLocksOnSubLinks((Node *) securityQuals, &context);
2312 : 504 : (void) acquireLocksOnSubLinks((Node *) withCheckOptions,
2313 : : &context);
2314 : :
2315 : : /*
2316 : : * Now that we have the locks on anything added by
2317 : : * get_row_security_policies, fire any RIR rules for them.
2318 : : */
540 nathan@postgresql.or 2319 : 504 : fire_context.activeRIRs = activeRIRs;
2320 : 504 : fire_context.hasRowSecurity = false;
2321 : :
4000 bruce@momjian.us 2322 : 504 : expression_tree_walker((Node *) securityQuals,
2323 : : fireRIRonSubLink, &fire_context);
2324 : :
2325 : 456 : expression_tree_walker((Node *) withCheckOptions,
2326 : : fireRIRonSubLink, &fire_context);
2327 : :
2328 : : /*
2329 : : * We can ignore the value of fire_context.hasRowSecurity
2330 : : * since we only reach this code in cases where hasRowSecurity
2331 : : * is already true.
2332 : : */
540 nathan@postgresql.or 2333 [ - + ]: 452 : Assert(hasRowSecurity);
2334 : :
2484 tgl@sss.pgh.pa.us 2335 : 452 : activeRIRs = list_delete_last(activeRIRs);
2336 : : }
2337 : :
2338 : : /*
2339 : : * Add the new security barrier quals to the start of the RTE's
2340 : : * list so that they get applied before any existing barrier quals
2341 : : * (which would have come from a security-barrier view, and should
2342 : : * get lower priority than RLS conditions on the table itself).
2343 : : */
4031 sfrost@snowman.net 2344 : 4268 : rte->securityQuals = list_concat(securityQuals,
2345 : 2134 : rte->securityQuals);
2346 : :
2347 : 2134 : parsetree->withCheckOptions = list_concat(withCheckOptions,
3240 tgl@sss.pgh.pa.us 2348 : 2134 : parsetree->withCheckOptions);
2349 : : }
2350 : :
2351 : : /*
2352 : : * Make sure the query is marked correctly if row-level security
2353 : : * applies, or if the new quals had sublinks.
2354 : : */
4031 sfrost@snowman.net 2355 [ + + ]: 306346 : if (hasRowSecurity)
2356 : 2587 : parsetree->hasRowSecurity = true;
2357 [ + + ]: 306346 : if (hasSubLinks)
2358 : 452 : parsetree->hasSubLinks = true;
2359 : :
2661 andres@anarazel.de 2360 : 306346 : table_close(rel, NoLock);
2361 : : }
2362 : :
10077 bruce@momjian.us 2363 : 374663 : return parsetree;
2364 : : }
2365 : :
2366 : :
2367 : : /*
2368 : : * Modify the given query by adding 'AND rule_qual IS NOT TRUE' to its
2369 : : * qualification. This is used to generate suitable "else clauses" for
2370 : : * conditional INSTEAD rules. (Unfortunately we must use "x IS NOT TRUE",
2371 : : * not just "NOT x" which the planner is much smarter about, else we will
2372 : : * do the wrong thing when the qual evaluates to NULL.)
2373 : : *
2374 : : * The rule_qual may contain references to OLD or NEW. OLD references are
2375 : : * replaced by references to the specified rt_index (the relation that the
2376 : : * rule applies to). NEW references are only possible for INSERT and UPDATE
2377 : : * queries on the relation itself, and so they should be replaced by copies
2378 : : * of the related entries in the query's own targetlist.
2379 : : */
2380 : : static Query *
8598 tgl@sss.pgh.pa.us 2381 : 304 : CopyAndAddInvertedQual(Query *parsetree,
2382 : : Node *rule_qual,
2383 : : int rt_index,
2384 : : CmdType event)
2385 : : {
2386 : : /* Don't scribble on the passed qual (it's in the relcache!) */
3344 peter_e@gmx.net 2387 : 304 : Node *new_qual = copyObject(rule_qual);
2388 : : acquireLocksOnSubLinks_context context;
2389 : :
4443 tgl@sss.pgh.pa.us 2390 : 304 : context.for_execute = true;
2391 : :
2392 : : /*
2393 : : * In case there are subqueries in the qual, acquire necessary locks and
2394 : : * fix any deleted JOIN RTE entries. (This is somewhat redundant with
2395 : : * rewriteRuleAction, but not entirely ... consider restructuring so that
2396 : : * we only need to process the qual this way once.)
2397 : : */
2398 : 304 : (void) acquireLocksOnSubLinks(new_qual, &context);
2399 : :
2400 : : /* Fix references to OLD */
9282 2401 : 304 : ChangeVarNodes(new_qual, PRS2_OLD_VARNO, rt_index, 0);
2402 : : /* Fix references to NEW */
2403 [ + + + + ]: 304 : if (event == CMD_INSERT || event == CMD_UPDATE)
2404 : : {
14 rguo@postgresql.org 2405 : 296 : RangeTblEntry *rte = rt_fetch(rt_index, parsetree->rtable);
2406 : : Relation rel;
2407 : : List *gen_cols;
2408 : :
2409 : : /*
2410 : : * As in rewriteRuleAction, build entries for generated columns so
2411 : : * that new.gen_col in the rule qualification can be rewritten
2412 : : * correctly.
2413 : : */
2414 : 296 : rel = relation_open(rte->relid, NoLock);
2415 : 296 : gen_cols = get_generated_columns(rel, PRS2_NEW_VARNO, true);
2416 : 296 : relation_close(rel, NoLock);
2417 : :
2418 : : /*
2419 : : * The generated column expressions refer to new.attribute, so they
2420 : : * must be rewritten before they can be used as replacements.
2421 : : */
2422 : : gen_cols = (List *)
2423 [ + + ]: 296 : ReplaceVarsFromTargetList((Node *) gen_cols,
2424 : : PRS2_NEW_VARNO,
2425 : : 0,
2426 : : rte,
2427 : : parsetree->targetList,
2428 : : parsetree->resultRelation,
2429 : : (event == CMD_UPDATE) ?
2430 : : REPLACEVARS_CHANGE_VARNO :
2431 : : REPLACEVARS_SUBSTITUTE_NULL,
2432 : : rt_index,
2433 : : &parsetree->hasSubLinks);
2434 : :
4926 tgl@sss.pgh.pa.us 2435 [ + + ]: 592 : new_qual = ReplaceVarsFromTargetList(new_qual,
2436 : : PRS2_NEW_VARNO,
2437 : : 0,
2438 : : rte,
2439 : : list_concat(gen_cols,
14 rguo@postgresql.org 2440 : 296 : parsetree->targetList),
2441 : : parsetree->resultRelation,
2442 : : (event == CMD_UPDATE) ?
2443 : : REPLACEVARS_CHANGE_VARNO :
2444 : : REPLACEVARS_SUBSTITUTE_NULL,
2445 : : rt_index,
2446 : : &parsetree->hasSubLinks);
2447 : : }
2448 : : /* And attach the fixed qual */
7641 tgl@sss.pgh.pa.us 2449 : 304 : AddInvertedQual(parsetree, new_qual);
2450 : :
2451 : 304 : return parsetree;
2452 : : }
2453 : :
2454 : :
2455 : : /*
2456 : : * fireRules -
2457 : : * Iterate through rule locks applying rules.
2458 : : *
2459 : : * Input arguments:
2460 : : * parsetree - original query
2461 : : * rt_index - RT index of result relation in original query
2462 : : * event - type of rule event
2463 : : * locks - list of rules to fire
2464 : : * Output arguments:
2465 : : * *instead_flag - set true if any unqualified INSTEAD rule is found
2466 : : * (must be initialized to false)
2467 : : * *returning_flag - set true if we rewrite RETURNING clause in any rule
2468 : : * (must be initialized to false)
2469 : : * *qual_product - filled with modified original query if any qualified
2470 : : * INSTEAD rule is found (must be initialized to NULL)
2471 : : * Return value:
2472 : : * list of rule actions adjusted for use with this query
2473 : : *
2474 : : * Qualified INSTEAD rules generate their action with the qualification
2475 : : * condition added. They also generate a modified version of the original
2476 : : * query with the negated qualification added, so that it will run only for
2477 : : * rows that the qualified action doesn't act on. (If there are multiple
2478 : : * qualified INSTEAD rules, we AND all the negated quals onto a single
2479 : : * modified original query.) We won't execute the original, unmodified
2480 : : * query if we find either qualified or unqualified INSTEAD rules. If
2481 : : * we find both, the modified original query is discarded too.
2482 : : */
2483 : : static List *
10466 bruce@momjian.us 2484 : 56532 : fireRules(Query *parsetree,
2485 : : int rt_index,
2486 : : CmdType event,
2487 : : List *locks,
2488 : : bool *instead_flag,
2489 : : bool *returning_flag,
2490 : : Query **qual_product)
2491 : : {
2492 : 56532 : List *results = NIL;
2493 : : ListCell *l;
2494 : :
8014 neilc@samurai.com 2495 [ + + + + : 57624 : foreach(l, locks)
+ + ]
2496 : : {
2497 : 1100 : RewriteRule *rule_lock = (RewriteRule *) lfirst(l);
8599 tgl@sss.pgh.pa.us 2498 : 1100 : Node *event_qual = rule_lock->qual;
2499 : 1100 : List *actions = rule_lock->actions;
2500 : : QuerySource qsrc;
2501 : : ListCell *r;
2502 : :
2503 : : /* Determine correct QuerySource value for actions */
8604 2504 [ + + ]: 1100 : if (rule_lock->isInstead)
2505 : : {
2506 [ + + ]: 816 : if (event_qual != NULL)
2507 : 308 : qsrc = QSRC_QUAL_INSTEAD_RULE;
2508 : : else
2509 : : {
2510 : 508 : qsrc = QSRC_INSTEAD_RULE;
8310 bruce@momjian.us 2511 : 508 : *instead_flag = true; /* report unqualified INSTEAD */
2512 : : }
2513 : : }
2514 : : else
8604 tgl@sss.pgh.pa.us 2515 : 284 : qsrc = QSRC_NON_INSTEAD_RULE;
2516 : :
2517 [ + + ]: 1100 : if (qsrc == QSRC_QUAL_INSTEAD_RULE)
2518 : : {
2519 : : /*
2520 : : * If there are INSTEAD rules with qualifications, the original
2521 : : * query is still performed. But all the negated rule
2522 : : * qualifications of the INSTEAD rules are added so it does its
2523 : : * actions only in cases where the rule quals of all INSTEAD rules
2524 : : * are false. Think of it as the default action in a case. We save
2525 : : * this in *qual_product so RewriteQuery() can add it to the query
2526 : : * list after we mangled it up enough.
2527 : : *
2528 : : * If we have already found an unqualified INSTEAD rule, then
2529 : : * *qual_product won't be used, so don't bother building it.
2530 : : */
8310 bruce@momjian.us 2531 [ + + ]: 308 : if (!*instead_flag)
2532 : : {
8599 tgl@sss.pgh.pa.us 2533 [ + + ]: 304 : if (*qual_product == NULL)
7641 2534 : 248 : *qual_product = copyObject(parsetree);
8598 2535 : 304 : *qual_product = CopyAndAddInvertedQual(*qual_product,
2536 : : event_qual,
2537 : : rt_index,
2538 : : event);
2539 : : }
2540 : : }
2541 : :
2542 : : /* Now process the rule's actions and add them to the result list */
10467 bruce@momjian.us 2543 [ + - + + : 2228 : foreach(r, actions)
+ + ]
2544 : : {
10466 2545 : 1136 : Query *rule_action = lfirst(r);
2546 : :
10122 scrappy@hub.org 2547 [ + + ]: 1136 : if (rule_action->commandType == CMD_NOTHING)
2548 : 148 : continue;
2549 : :
9092 tgl@sss.pgh.pa.us 2550 : 988 : rule_action = rewriteRuleAction(parsetree, rule_action,
2551 : : event_qual, rt_index, event,
2552 : : returning_flag);
2553 : :
8604 2554 : 980 : rule_action->querySource = qsrc;
3240 2555 : 980 : rule_action->canSetTag = false; /* might change later */
2556 : :
9092 2557 : 980 : results = lappend(results, rule_action);
2558 : : }
2559 : : }
2560 : :
10467 bruce@momjian.us 2561 : 56524 : return results;
2562 : : }
2563 : :
2564 : :
2565 : : /*
2566 : : * get_view_query - get the Query from a view's _RETURN rule.
2567 : : *
2568 : : * Caller should have verified that the relation is a view, and therefore
2569 : : * we should find an ON SELECT action.
2570 : : *
2571 : : * Note that the pointer returned is into the relcache and therefore must
2572 : : * be treated as read-only to the caller and not modified or scribbled on.
2573 : : */
2574 : : Query *
4896 tgl@sss.pgh.pa.us 2575 : 4000 : get_view_query(Relation view)
2576 : : {
2577 : : int i;
2578 : :
2579 [ - + ]: 4000 : Assert(view->rd_rel->relkind == RELKIND_VIEW);
2580 : :
2581 [ + - ]: 4000 : for (i = 0; i < view->rd_rules->numLocks; i++)
2582 : : {
2583 : 4000 : RewriteRule *rule = view->rd_rules->rules[i];
2584 : :
2585 [ + - ]: 4000 : if (rule->event == CMD_SELECT)
2586 : : {
2587 : : /* A _RETURN rule should have only one action */
2588 [ - + ]: 4000 : if (list_length(rule->actions) != 1)
4896 tgl@sss.pgh.pa.us 2589 [ # # ]:UBC 0 : elog(ERROR, "invalid _RETURN rule action specification");
2590 : :
4896 tgl@sss.pgh.pa.us 2591 :CBC 4000 : return (Query *) linitial(rule->actions);
2592 : : }
2593 : : }
2594 : :
4896 tgl@sss.pgh.pa.us 2595 [ # # ]:UBC 0 : elog(ERROR, "failed to find _RETURN rule for view");
2596 : : return NULL; /* keep compiler quiet */
2597 : : }
2598 : :
2599 : :
2600 : : /*
2601 : : * view_has_instead_trigger - does view have an INSTEAD OF trigger for event?
2602 : : *
2603 : : * If it does, we don't want to treat it as auto-updatable. This test can't
2604 : : * be folded into view_query_is_auto_updatable because it's not an error
2605 : : * condition.
2606 : : *
2607 : : * For MERGE, this will return true if there is an INSTEAD OF trigger for
2608 : : * every action in mergeActionList, and false if there are any actions that
2609 : : * lack an INSTEAD OF trigger. If there are no data-modifying MERGE actions
2610 : : * (only DO NOTHING actions), true is returned so that the view is treated
2611 : : * as trigger-updatable, rather than erroring out if it's not auto-updatable.
2612 : : */
2613 : : bool
796 dean.a.rasheed@gmail 2614 :CBC 3721 : view_has_instead_trigger(Relation view, CmdType event, List *mergeActionList)
2615 : : {
4896 tgl@sss.pgh.pa.us 2616 : 3721 : TriggerDesc *trigDesc = view->trigdesc;
2617 : :
2618 [ + + + + : 3721 : switch (event)
- ]
2619 : : {
2620 : 1238 : case CMD_INSERT:
2621 [ + + + - ]: 1238 : if (trigDesc && trigDesc->trig_insert_instead_row)
2622 : 174 : return true;
2623 : 1064 : break;
2624 : 1373 : case CMD_UPDATE:
2625 [ + + + - ]: 1373 : if (trigDesc && trigDesc->trig_update_instead_row)
2626 : 210 : return true;
2627 : 1163 : break;
2628 : 410 : case CMD_DELETE:
2629 [ + + + - ]: 410 : if (trigDesc && trigDesc->trig_delete_instead_row)
2630 : 70 : return true;
2631 : 340 : break;
796 dean.a.rasheed@gmail 2632 : 700 : case CMD_MERGE:
2633 [ + - + + : 988 : foreach_node(MergeAction, action, mergeActionList)
+ + ]
2634 : : {
2635 [ + + + + : 780 : switch (action->commandType)
- ]
2636 : : {
2637 : 136 : case CMD_INSERT:
2638 [ + + + + ]: 136 : if (!trigDesc || !trigDesc->trig_insert_instead_row)
2639 : 596 : return false;
2640 : 56 : break;
2641 : 496 : case CMD_UPDATE:
2642 [ + + - + ]: 496 : if (!trigDesc || !trigDesc->trig_update_instead_row)
2643 : 424 : return false;
2644 : 72 : break;
2645 : 108 : case CMD_DELETE:
2646 [ + + + + ]: 108 : if (!trigDesc || !trigDesc->trig_delete_instead_row)
2647 : 92 : return false;
2648 : 16 : break;
2649 : 40 : case CMD_NOTHING:
2650 : : /* No trigger required */
2651 : 40 : break;
796 dean.a.rasheed@gmail 2652 :UBC 0 : default:
2653 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d", action->commandType);
2654 : : break;
2655 : : }
2656 : : }
796 dean.a.rasheed@gmail 2657 :CBC 104 : return true; /* no actions without an INSTEAD OF trigger */
4896 tgl@sss.pgh.pa.us 2658 :UBC 0 : default:
2659 [ # # ]: 0 : elog(ERROR, "unrecognized CmdType: %d", (int) event);
2660 : : break;
2661 : : }
4896 tgl@sss.pgh.pa.us 2662 :CBC 2567 : return false;
2663 : : }
2664 : :
2665 : :
2666 : : /*
2667 : : * view_col_is_auto_updatable - test whether the specified column of a view
2668 : : * is auto-updatable. Returns NULL (if the column can be updated) or a message
2669 : : * string giving the reason that it cannot be.
2670 : : *
2671 : : * The returned string has not been translated; if it is shown as an error
2672 : : * message, the caller should apply _() to translate it.
2673 : : *
2674 : : * Note that the checks performed here are local to this view. We do not check
2675 : : * whether the referenced column of the underlying base relation is updatable.
2676 : : */
2677 : : static const char *
4582 rhaas@postgresql.org 2678 : 9836 : view_col_is_auto_updatable(RangeTblRef *rtr, TargetEntry *tle)
2679 : : {
2680 : 9836 : Var *var = (Var *) tle->expr;
2681 : :
2682 : : /*
2683 : : * For now, the only updatable columns we support are those that are Vars
2684 : : * referring to user columns of the underlying base relation.
2685 : : *
2686 : : * The view targetlist may contain resjunk columns (e.g., a view defined
2687 : : * like "SELECT * FROM t ORDER BY a+b" is auto-updatable) but such columns
2688 : : * are not auto-updatable, and in fact should never appear in the outer
2689 : : * query's targetlist.
2690 : : */
2691 [ + + ]: 9836 : if (tle->resjunk)
2692 : 120 : return gettext_noop("Junk view columns are not updatable.");
2693 : :
2694 [ + + ]: 9716 : if (!IsA(var, Var) ||
2695 [ + - ]: 8720 : var->varno != rtr->rtindex ||
2696 [ - + ]: 8720 : var->varlevelsup != 0)
2697 : 996 : return gettext_noop("View columns that are not columns of their base relation are not updatable.");
2698 : :
2699 [ + + ]: 8720 : if (var->varattno < 0)
2700 : 268 : return gettext_noop("View columns that refer to system columns are not updatable.");
2701 : :
2702 [ - + ]: 8452 : if (var->varattno == 0)
4582 rhaas@postgresql.org 2703 :UBC 0 : return gettext_noop("View columns that return whole-row references are not updatable.");
2704 : :
4582 rhaas@postgresql.org 2705 :CBC 8452 : return NULL; /* the view column is updatable */
2706 : : }
2707 : :
2708 : :
2709 : : /*
2710 : : * view_query_is_auto_updatable - test whether the specified view definition
2711 : : * represents an auto-updatable view. Returns NULL (if the view can be updated)
2712 : : * or a message string giving the reason that it cannot be.
2713 : : *
2714 : : * The returned string has not been translated; if it is shown as an error
2715 : : * message, the caller should apply _() to translate it.
2716 : : *
2717 : : * If check_cols is true, the view is required to have at least one updatable
2718 : : * column (necessary for INSERT/UPDATE). Otherwise the view's columns are not
2719 : : * checked for updatability. See also view_cols_are_auto_updatable.
2720 : : *
2721 : : * Note that the checks performed here are only based on the view definition.
2722 : : * We do not check whether any base relations referred to by the view are
2723 : : * updatable.
2724 : : */
2725 : : const char *
4406 sfrost@snowman.net 2726 : 3843 : view_query_is_auto_updatable(Query *viewquery, bool check_cols)
2727 : : {
2728 : : RangeTblRef *rtr;
2729 : : RangeTblEntry *base_rte;
2730 : :
2731 : : /*----------
2732 : : * Check if the view is simply updatable. According to SQL-92 this means:
2733 : : * - No DISTINCT clause.
2734 : : * - Each TLE is a column reference, and each column appears at most once.
2735 : : * - FROM contains exactly one base relation.
2736 : : * - No GROUP BY or HAVING clauses.
2737 : : * - No set operations (UNION, INTERSECT or EXCEPT).
2738 : : * - No sub-queries in the WHERE clause that reference the target table.
2739 : : *
2740 : : * We ignore that last restriction since it would be complex to enforce
2741 : : * and there isn't any actual benefit to disallowing sub-queries. (The
2742 : : * semantic issues that the standard is presumably concerned about don't
2743 : : * arise in Postgres, since any such sub-query will not see any updates
2744 : : * executed by the outer query anyway, thanks to MVCC snapshotting.)
2745 : : *
2746 : : * We also relax the second restriction by supporting part of SQL:1999
2747 : : * feature T111, which allows for a mix of updatable and non-updatable
2748 : : * columns, provided that an INSERT or UPDATE doesn't attempt to assign to
2749 : : * a non-updatable column.
2750 : : *
2751 : : * In addition we impose these constraints, involving features that are
2752 : : * not part of SQL-92:
2753 : : * - No CTEs (WITH clauses).
2754 : : * - No OFFSET or LIMIT clauses (this matches a SQL:2008 restriction).
2755 : : * - No system columns (including whole-row references) in the tlist.
2756 : : * - No window functions in the tlist.
2757 : : * - No set-returning functions in the tlist.
2758 : : *
2759 : : * Note that we do these checks without recursively expanding the view.
2760 : : * If the base relation is a view, we'll recursively deal with it later.
2761 : : *----------
2762 : : */
4896 tgl@sss.pgh.pa.us 2763 [ + + ]: 3843 : if (viewquery->distinctClause != NIL)
2764 : 48 : return gettext_noop("Views containing DISTINCT are not automatically updatable.");
2765 : :
4007 andres@anarazel.de 2766 [ + + - + ]: 3795 : if (viewquery->groupClause != NIL || viewquery->groupingSets)
4896 tgl@sss.pgh.pa.us 2767 : 24 : return gettext_noop("Views containing GROUP BY are not automatically updatable.");
2768 : :
2769 [ + + ]: 3771 : if (viewquery->havingQual != NULL)
2770 : 20 : return gettext_noop("Views containing HAVING are not automatically updatable.");
2771 : :
2772 [ + + ]: 3751 : if (viewquery->setOperations != NULL)
4769 peter_e@gmx.net 2773 : 24 : return gettext_noop("Views containing UNION, INTERSECT, or EXCEPT are not automatically updatable.");
2774 : :
4896 tgl@sss.pgh.pa.us 2775 [ + + ]: 3727 : if (viewquery->cteList != NIL)
2776 : 24 : return gettext_noop("Views containing WITH are not automatically updatable.");
2777 : :
2778 [ + + + + ]: 3703 : if (viewquery->limitOffset != NULL || viewquery->limitCount != NULL)
2779 : 384 : return gettext_noop("Views containing LIMIT or OFFSET are not automatically updatable.");
2780 : :
2781 : : /*
2782 : : * We must not allow window functions or set returning functions in the
2783 : : * targetlist. Otherwise we might end up inserting them into the quals of
2784 : : * the main query. We must also check for aggregates in the targetlist in
2785 : : * case they appear without a GROUP BY.
2786 : : *
2787 : : * These restrictions ensure that each row of the view corresponds to a
2788 : : * unique row in the underlying base relation.
2789 : : */
4582 rhaas@postgresql.org 2790 [ + + ]: 3319 : if (viewquery->hasAggs)
4267 peter_e@gmx.net 2791 : 20 : return gettext_noop("Views that return aggregate functions are not automatically updatable.");
2792 : :
4582 rhaas@postgresql.org 2793 [ + + ]: 3299 : if (viewquery->hasWindowFuncs)
4267 peter_e@gmx.net 2794 : 24 : return gettext_noop("Views that return window functions are not automatically updatable.");
2795 : :
3521 tgl@sss.pgh.pa.us 2796 [ + + ]: 3275 : if (viewquery->hasTargetSRFs)
4582 rhaas@postgresql.org 2797 : 28 : return gettext_noop("Views that return set-returning functions are not automatically updatable.");
2798 : :
2799 : : /*
2800 : : * The view query should select from a single base relation, which must be
2801 : : * a table or another view.
2802 : : */
4896 tgl@sss.pgh.pa.us 2803 [ + + ]: 3247 : if (list_length(viewquery->jointree->fromlist) != 1)
2804 : 44 : return gettext_noop("Views that do not select from a single table or view are not automatically updatable.");
2805 : :
2806 : 3203 : rtr = (RangeTblRef *) linitial(viewquery->jointree->fromlist);
2807 [ - + ]: 3203 : if (!IsA(rtr, RangeTblRef))
4896 tgl@sss.pgh.pa.us 2808 :UBC 0 : return gettext_noop("Views that do not select from a single table or view are not automatically updatable.");
2809 : :
4896 tgl@sss.pgh.pa.us 2810 :CBC 3203 : base_rte = rt_fetch(rtr->rtindex, viewquery->rtable);
2811 [ + + ]: 3203 : if (base_rte->rtekind != RTE_RELATION ||
2812 [ + + ]: 3127 : (base_rte->relkind != RELKIND_RELATION &&
4710 2813 [ + + ]: 1198 : base_rte->relkind != RELKIND_FOREIGN_TABLE &&
3388 rhaas@postgresql.org 2814 [ + + ]: 1187 : base_rte->relkind != RELKIND_VIEW &&
2815 [ + + ]: 167 : base_rte->relkind != RELKIND_PARTITIONED_TABLE))
4896 tgl@sss.pgh.pa.us 2816 : 104 : return gettext_noop("Views that do not select from a single table or view are not automatically updatable.");
2817 : :
4008 simon@2ndQuadrant.co 2818 [ + + ]: 3099 : if (base_rte->tablesample)
2819 : 4 : return gettext_noop("Views containing TABLESAMPLE are not automatically updatable.");
2820 : :
2821 : : /*
2822 : : * Check that the view has at least one updatable column. This is required
2823 : : * for INSERT/UPDATE but not for DELETE.
2824 : : */
4582 rhaas@postgresql.org 2825 [ + + ]: 3095 : if (check_cols)
2826 : : {
2827 : : ListCell *cell;
2828 : : bool found;
2829 : :
2830 : 2135 : found = false;
2831 [ + - + - : 2259 : foreach(cell, viewquery->targetList)
+ - ]
2832 : : {
2833 : 2259 : TargetEntry *tle = (TargetEntry *) lfirst(cell);
2834 : :
2835 [ + + ]: 2259 : if (view_col_is_auto_updatable(rtr, tle) == NULL)
2836 : : {
2837 : 2135 : found = true;
2838 : 2135 : break;
2839 : : }
2840 : : }
2841 : :
2842 [ - + ]: 2135 : if (!found)
4582 rhaas@postgresql.org 2843 :UBC 0 : return gettext_noop("Views that have no updatable columns are not automatically updatable.");
2844 : : }
2845 : :
4582 rhaas@postgresql.org 2846 :CBC 3095 : return NULL; /* the view is updatable */
2847 : : }
2848 : :
2849 : :
2850 : : /*
2851 : : * view_cols_are_auto_updatable - test whether all of the required columns of
2852 : : * an auto-updatable view are actually updatable. Returns NULL (if all the
2853 : : * required columns can be updated) or a message string giving the reason that
2854 : : * they cannot be.
2855 : : *
2856 : : * The returned string has not been translated; if it is shown as an error
2857 : : * message, the caller should apply _() to translate it.
2858 : : *
2859 : : * This should be used for INSERT/UPDATE to ensure that we don't attempt to
2860 : : * assign to any non-updatable columns.
2861 : : *
2862 : : * Additionally it may be used to retrieve the set of updatable columns in the
2863 : : * view, or if one or more of the required columns is not updatable, the name
2864 : : * of the first offending non-updatable column.
2865 : : *
2866 : : * The caller must have already verified that this is an auto-updatable view
2867 : : * using view_query_is_auto_updatable.
2868 : : *
2869 : : * Note that the checks performed here are only based on the view definition.
2870 : : * We do not check whether the referenced columns of the base relation are
2871 : : * updatable.
2872 : : */
2873 : : static const char *
2874 : 2735 : view_cols_are_auto_updatable(Query *viewquery,
2875 : : Bitmapset *required_cols,
2876 : : Bitmapset **updatable_cols,
2877 : : char **non_updatable_col)
2878 : : {
2879 : : RangeTblRef *rtr;
2880 : : AttrNumber col;
2881 : : ListCell *cell;
2882 : :
2883 : : /*
2884 : : * The caller should have verified that this view is auto-updatable and so
2885 : : * there should be a single base relation.
2886 : : */
2887 [ - + ]: 2735 : Assert(list_length(viewquery->jointree->fromlist) == 1);
3312 tgl@sss.pgh.pa.us 2888 : 2735 : rtr = linitial_node(RangeTblRef, viewquery->jointree->fromlist);
2889 : :
2890 : : /* Initialize the optional return values */
4582 rhaas@postgresql.org 2891 [ + + ]: 2735 : if (updatable_cols != NULL)
2892 : 700 : *updatable_cols = NULL;
2893 [ + + ]: 2735 : if (non_updatable_col != NULL)
2894 : 2035 : *non_updatable_col = NULL;
2895 : :
2896 : : /* Test each view column for updatability */
2897 : 2735 : col = -FirstLowInvalidHeapAttributeNumber;
2898 [ + - + + : 10232 : foreach(cell, viewquery->targetList)
+ + ]
2899 : : {
2900 : 7577 : TargetEntry *tle = (TargetEntry *) lfirst(cell);
2901 : : const char *col_update_detail;
2902 : :
2903 : 7577 : col++;
2904 : 7577 : col_update_detail = view_col_is_auto_updatable(rtr, tle);
2905 : :
2906 [ + + ]: 7577 : if (col_update_detail == NULL)
2907 : : {
2908 : : /* The column is updatable */
2909 [ + + ]: 6317 : if (updatable_cols != NULL)
2910 : 1424 : *updatable_cols = bms_add_member(*updatable_cols, col);
2911 : : }
2912 [ + + ]: 1260 : else if (bms_is_member(col, required_cols))
2913 : : {
2914 : : /* The required column is not updatable */
2915 [ + - ]: 80 : if (non_updatable_col != NULL)
2916 : 80 : *non_updatable_col = tle->resname;
2917 : 80 : return col_update_detail;
2918 : : }
2919 : : }
2920 : :
4382 bruce@momjian.us 2921 : 2655 : return NULL; /* all the required view columns are updatable */
2922 : : }
2923 : :
2924 : :
2925 : : /*
2926 : : * relation_is_updatable - determine which update events the specified
2927 : : * relation supports.
2928 : : *
2929 : : * Note that views may contain a mix of updatable and non-updatable columns.
2930 : : * For a view to support INSERT/UPDATE it must have at least one updatable
2931 : : * column, but there is no such restriction for DELETE. If include_cols is
2932 : : * non-NULL, then only the specified columns are considered when testing for
2933 : : * updatability.
2934 : : *
2935 : : * Unlike the preceding functions, this does recurse to look at a view's
2936 : : * base relations, so it needs to detect recursion. To do that, we pass
2937 : : * a list of currently-considered outer relations. External callers need
2938 : : * only pass NIL.
2939 : : *
2940 : : * This is used for the information_schema views, which have separate concepts
2941 : : * of "updatable" and "trigger updatable". A relation is "updatable" if it
2942 : : * can be updated without the need for triggers (either because it has a
2943 : : * suitable RULE, or because it is simple enough to be automatically updated).
2944 : : * A relation is "trigger updatable" if it has a suitable INSTEAD OF trigger.
2945 : : * The SQL standard regards this as not necessarily updatable, presumably
2946 : : * because there is no way of knowing what the trigger will actually do.
2947 : : * The information_schema views therefore call this function with
2948 : : * include_triggers = false. However, other callers might only care whether
2949 : : * data-modifying SQL will work, so they can pass include_triggers = true
2950 : : * to have trigger updatability included in the result.
2951 : : *
2952 : : * The return value is a bitmask of rule event numbers indicating which of
2953 : : * the INSERT, UPDATE and DELETE operations are supported. (We do it this way
2954 : : * so that we can test for UPDATE plus DELETE support in a single call.)
2955 : : */
2956 : : int
4582 rhaas@postgresql.org 2957 : 1408 : relation_is_updatable(Oid reloid,
2958 : : List *outer_reloids,
2959 : : bool include_triggers,
2960 : : Bitmapset *include_cols)
2961 : : {
4710 tgl@sss.pgh.pa.us 2962 : 1408 : int events = 0;
2963 : : Relation rel;
2964 : : RuleLock *rulelocks;
2965 : :
2966 : : #define ALL_EVENTS ((1 << CMD_INSERT) | (1 << CMD_UPDATE) | (1 << CMD_DELETE))
2967 : :
2968 : : /* Since this function recurses, it could be driven to stack overflow */
2357 2969 : 1408 : check_stack_depth();
2970 : :
4896 2971 : 1408 : rel = try_relation_open(reloid, AccessShareLock);
2972 : :
2973 : : /*
2974 : : * If the relation doesn't exist, return zero rather than throwing an
2975 : : * error. This is helpful since scanning an information_schema view under
2976 : : * MVCC rules can result in referencing rels that have actually been
2977 : : * deleted already.
2978 : : */
2979 [ - + ]: 1408 : if (rel == NULL)
4710 tgl@sss.pgh.pa.us 2980 :UBC 0 : return 0;
2981 : :
2982 : : /* If we detect a recursive view, report that it is not updatable */
2357 tgl@sss.pgh.pa.us 2983 [ - + ]:CBC 1408 : if (list_member_oid(outer_reloids, RelationGetRelid(rel)))
2984 : : {
2357 tgl@sss.pgh.pa.us 2985 :UBC 0 : relation_close(rel, AccessShareLock);
2986 : 0 : return 0;
2987 : : }
2988 : :
2989 : : /* If the relation is a table, it is always updatable */
3248 dean.a.rasheed@gmail 2990 [ + - ]:CBC 1408 : if (rel->rd_rel->relkind == RELKIND_RELATION ||
2991 [ + + ]: 1408 : rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
2992 : : {
4710 tgl@sss.pgh.pa.us 2993 : 12 : relation_close(rel, AccessShareLock);
2994 : 12 : return ALL_EVENTS;
2995 : : }
2996 : :
2997 : : /* Look for unconditional DO INSTEAD rules, and note supported events */
4896 2998 : 1396 : rulelocks = rel->rd_rules;
2999 [ + - ]: 1396 : if (rulelocks != NULL)
3000 : : {
3001 : : int i;
3002 : :
3003 [ + + ]: 3040 : for (i = 0; i < rulelocks->numLocks; i++)
3004 : : {
3005 [ + + ]: 1644 : if (rulelocks->rules[i]->isInstead &&
3006 [ + - ]: 1636 : rulelocks->rules[i]->qual == NULL)
3007 : : {
4710 3008 : 1636 : events |= ((1 << rulelocks->rules[i]->event) & ALL_EVENTS);
3009 : : }
3010 : : }
3011 : :
3012 : : /* If we have rules for all events, we're done */
3013 [ + + ]: 1396 : if (events == ALL_EVENTS)
3014 : : {
4896 3015 : 40 : relation_close(rel, AccessShareLock);
4710 3016 : 40 : return events;
3017 : : }
3018 : : }
3019 : :
3020 : : /* Similarly look for INSTEAD OF triggers, if they are to be included */
3021 [ - + ]: 1356 : if (include_triggers)
3022 : : {
4710 tgl@sss.pgh.pa.us 3023 :UBC 0 : TriggerDesc *trigDesc = rel->trigdesc;
3024 : :
3025 [ # # ]: 0 : if (trigDesc)
3026 : : {
3027 [ # # ]: 0 : if (trigDesc->trig_insert_instead_row)
3028 : 0 : events |= (1 << CMD_INSERT);
3029 [ # # ]: 0 : if (trigDesc->trig_update_instead_row)
3030 : 0 : events |= (1 << CMD_UPDATE);
3031 [ # # ]: 0 : if (trigDesc->trig_delete_instead_row)
3032 : 0 : events |= (1 << CMD_DELETE);
3033 : :
3034 : : /* If we have triggers for all events, we're done */
3035 [ # # ]: 0 : if (events == ALL_EVENTS)
3036 : : {
3037 : 0 : relation_close(rel, AccessShareLock);
3038 : 0 : return events;
3039 : : }
3040 : : }
3041 : : }
3042 : :
3043 : : /* If this is a foreign table, check which update events it supports */
4710 tgl@sss.pgh.pa.us 3044 [ - + ]:CBC 1356 : if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
3045 : : {
4710 tgl@sss.pgh.pa.us 3046 :UBC 0 : FdwRoutine *fdwroutine = GetFdwRoutineForRelation(rel, false);
3047 : :
3048 [ # # ]: 0 : if (fdwroutine->IsForeignRelUpdatable != NULL)
3049 : 0 : events |= fdwroutine->IsForeignRelUpdatable(rel);
3050 : : else
3051 : : {
3052 : : /* Assume presence of executor functions is sufficient */
3053 [ # # ]: 0 : if (fdwroutine->ExecForeignInsert != NULL)
3054 : 0 : events |= (1 << CMD_INSERT);
3055 [ # # ]: 0 : if (fdwroutine->ExecForeignUpdate != NULL)
3056 : 0 : events |= (1 << CMD_UPDATE);
3057 [ # # ]: 0 : if (fdwroutine->ExecForeignDelete != NULL)
3058 : 0 : events |= (1 << CMD_DELETE);
3059 : : }
3060 : :
3061 : 0 : relation_close(rel, AccessShareLock);
3062 : 0 : return events;
3063 : : }
3064 : :
3065 : : /* Check if this is an automatically updatable view */
4582 rhaas@postgresql.org 3066 [ + - ]:CBC 1356 : if (rel->rd_rel->relkind == RELKIND_VIEW)
3067 : : {
3068 : 1356 : Query *viewquery = get_view_query(rel);
3069 : :
4406 sfrost@snowman.net 3070 [ + + ]: 1356 : if (view_query_is_auto_updatable(viewquery, false) == NULL)
3071 : : {
3072 : : Bitmapset *updatable_cols;
3073 : : int auto_events;
3074 : : RangeTblRef *rtr;
3075 : : RangeTblEntry *base_rte;
3076 : : Oid baseoid;
3077 : :
3078 : : /*
3079 : : * Determine which of the view's columns are updatable. If there
3080 : : * are none within the set of columns we are looking at, then the
3081 : : * view doesn't support INSERT/UPDATE, but it may still support
3082 : : * DELETE.
3083 : : */
4582 rhaas@postgresql.org 3084 : 700 : view_cols_are_auto_updatable(viewquery, NULL,
3085 : : &updatable_cols, NULL);
3086 : :
3087 [ + + ]: 700 : if (include_cols != NULL)
3088 : 384 : updatable_cols = bms_int_members(updatable_cols, include_cols);
3089 : :
3090 [ + + ]: 700 : if (bms_is_empty(updatable_cols))
3240 tgl@sss.pgh.pa.us 3091 : 100 : auto_events = (1 << CMD_DELETE); /* May support DELETE */
3092 : : else
3093 : 600 : auto_events = ALL_EVENTS; /* May support all events */
3094 : :
3095 : : /*
3096 : : * The base relation must also support these update commands.
3097 : : * Tables are always updatable, but for any other kind of base
3098 : : * relation we must do a recursive check limited to the columns
3099 : : * referenced by the locally updatable columns in this view.
3100 : : */
4582 rhaas@postgresql.org 3101 : 700 : rtr = (RangeTblRef *) linitial(viewquery->jointree->fromlist);
3102 : 700 : base_rte = rt_fetch(rtr->rtindex, viewquery->rtable);
3103 [ - + ]: 700 : Assert(base_rte->rtekind == RTE_RELATION);
3104 : :
3248 dean.a.rasheed@gmail 3105 [ + + ]: 700 : if (base_rte->relkind != RELKIND_RELATION &&
3106 [ + + ]: 388 : base_rte->relkind != RELKIND_PARTITIONED_TABLE)
3107 : : {
4582 rhaas@postgresql.org 3108 : 368 : baseoid = base_rte->relid;
2357 tgl@sss.pgh.pa.us 3109 : 368 : outer_reloids = lappend_oid(outer_reloids,
3110 : : RelationGetRelid(rel));
4582 rhaas@postgresql.org 3111 : 368 : include_cols = adjust_view_column_set(updatable_cols,
3112 : : viewquery->targetList);
3113 : 368 : auto_events &= relation_is_updatable(baseoid,
3114 : : outer_reloids,
3115 : : include_triggers,
3116 : : include_cols);
2357 tgl@sss.pgh.pa.us 3117 : 368 : outer_reloids = list_delete_last(outer_reloids);
3118 : : }
4582 rhaas@postgresql.org 3119 : 700 : events |= auto_events;
3120 : : }
3121 : : }
3122 : :
3123 : : /* If we reach here, the relation may support some update commands */
4896 tgl@sss.pgh.pa.us 3124 : 1356 : relation_close(rel, AccessShareLock);
4710 3125 : 1356 : return events;
3126 : : }
3127 : :
3128 : :
3129 : : /*
3130 : : * adjust_view_column_set - map a set of column numbers according to targetlist
3131 : : *
3132 : : * This is used with simply-updatable views to map column-permissions sets for
3133 : : * the view columns onto the matching columns in the underlying base relation.
3134 : : * Relevant entries in the targetlist must be plain Vars of the underlying
3135 : : * relation (as per the checks above in view_query_is_auto_updatable).
3136 : : */
3137 : : static Bitmapset *
4896 3138 : 4790 : adjust_view_column_set(Bitmapset *cols, List *targetlist)
3139 : : {
3140 : 4790 : Bitmapset *result = NULL;
3141 : : int col;
3142 : :
4176 3143 : 4790 : col = -1;
3144 [ + + ]: 8307 : while ((col = bms_next_member(cols, col)) >= 0)
3145 : : {
3146 : : /* bit numbers are offset by FirstLowInvalidHeapAttributeNumber */
4896 3147 : 3517 : AttrNumber attno = col + FirstLowInvalidHeapAttributeNumber;
3148 : :
3149 [ - + ]: 3517 : if (attno == InvalidAttrNumber)
3150 : : {
3151 : : /*
3152 : : * There's a whole-row reference to the view. For permissions
3153 : : * purposes, treat it as a reference to each column available from
3154 : : * the view. (We should *not* convert this to a whole-row
3155 : : * reference to the base relation, since the view may not touch
3156 : : * all columns of the base relation.)
3157 : : */
3158 : : ListCell *lc;
3159 : :
4896 tgl@sss.pgh.pa.us 3160 [ # # # # :UBC 0 : foreach(lc, targetlist)
# # ]
3161 : : {
3312 3162 : 0 : TargetEntry *tle = lfirst_node(TargetEntry, lc);
3163 : : Var *var;
3164 : :
4896 3165 [ # # ]: 0 : if (tle->resjunk)
3166 : 0 : continue;
3360 peter_e@gmx.net 3167 : 0 : var = castNode(Var, tle->expr);
4896 tgl@sss.pgh.pa.us 3168 : 0 : result = bms_add_member(result,
3240 3169 : 0 : var->varattno - FirstLowInvalidHeapAttributeNumber);
3170 : : }
3171 : : }
3172 : : else
3173 : : {
3174 : : /*
3175 : : * Views do not have system columns, so we do not expect to see
3176 : : * any other system attnos here. If we do find one, the error
3177 : : * case will apply.
3178 : : */
4896 tgl@sss.pgh.pa.us 3179 :CBC 3517 : TargetEntry *tle = get_tle_by_resno(targetlist, attno);
3180 : :
3181 [ + - + - : 3517 : if (tle != NULL && !tle->resjunk && IsA(tle->expr, Var))
+ - ]
3182 : 3517 : {
3183 : 3517 : Var *var = (Var *) tle->expr;
3184 : :
3185 : 3517 : result = bms_add_member(result,
3240 3186 : 3517 : var->varattno - FirstLowInvalidHeapAttributeNumber);
3187 : : }
3188 : : else
4896 tgl@sss.pgh.pa.us 3189 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3190 : : attno);
3191 : : }
3192 : : }
3193 : :
4896 tgl@sss.pgh.pa.us 3194 :CBC 4790 : return result;
3195 : : }
3196 : :
3197 : :
3198 : : /*
3199 : : * error_view_not_updatable -
3200 : : * Report an error due to an attempt to update a non-updatable view.
3201 : : *
3202 : : * Generally this is expected to be called from the rewriter, with suitable
3203 : : * error detail explaining why the view is not updatable. Note, however, that
3204 : : * the executor also performs a just-in-case check that the target view is
3205 : : * updatable. That check is expected to never fail, but if it does, it will
3206 : : * call this function with NULL error detail --- see CheckValidResultRel().
3207 : : *
3208 : : * Note: for MERGE, at least one of the actions in mergeActionList is expected
3209 : : * to lack a suitable INSTEAD OF trigger --- see view_has_instead_trigger().
3210 : : */
3211 : : void
796 dean.a.rasheed@gmail 3212 : 104 : error_view_not_updatable(Relation view,
3213 : : CmdType command,
3214 : : List *mergeActionList,
3215 : : const char *detail)
3216 : : {
3217 : 104 : TriggerDesc *trigDesc = view->trigdesc;
3218 : :
3219 [ + + + + : 104 : switch (command)
- ]
3220 : : {
3221 : 16 : case CMD_INSERT:
3222 [ + - + - ]: 16 : ereport(ERROR,
3223 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3224 : : errmsg("cannot insert into view \"%s\"",
3225 : : RelationGetRelationName(view)),
3226 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3227 : : errhint("To enable inserting into the view, provide an INSTEAD OF INSERT trigger or an unconditional ON INSERT DO INSTEAD rule."));
3228 : : break;
3229 : 36 : case CMD_UPDATE:
3230 [ + - + - ]: 36 : ereport(ERROR,
3231 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3232 : : errmsg("cannot update view \"%s\"",
3233 : : RelationGetRelationName(view)),
3234 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3235 : : errhint("To enable updating the view, provide an INSTEAD OF UPDATE trigger or an unconditional ON UPDATE DO INSTEAD rule."));
3236 : : break;
3237 : 32 : case CMD_DELETE:
3238 [ + - + - ]: 32 : ereport(ERROR,
3239 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3240 : : errmsg("cannot delete from view \"%s\"",
3241 : : RelationGetRelationName(view)),
3242 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3243 : : errhint("To enable deleting from the view, provide an INSTEAD OF DELETE trigger or an unconditional ON DELETE DO INSTEAD rule."));
3244 : : break;
3245 : 20 : case CMD_MERGE:
3246 : :
3247 : : /*
3248 : : * Note that the error hints here differ from above, since MERGE
3249 : : * doesn't support rules.
3250 : : */
3251 [ + - + - : 24 : foreach_node(MergeAction, action, mergeActionList)
+ - ]
3252 : : {
3253 [ + + + - : 24 : switch (action->commandType)
- ]
3254 : : {
3255 : 8 : case CMD_INSERT:
3256 [ + + + - ]: 8 : if (!trigDesc || !trigDesc->trig_insert_instead_row)
3257 [ + - + - ]: 8 : ereport(ERROR,
3258 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3259 : : errmsg("cannot insert into view \"%s\"",
3260 : : RelationGetRelationName(view)),
3261 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3262 : : errhint("To enable inserting into the view using MERGE, provide an INSTEAD OF INSERT trigger."));
796 dean.a.rasheed@gmail 3263 :UBC 0 : break;
796 dean.a.rasheed@gmail 3264 :CBC 8 : case CMD_UPDATE:
3265 [ + + - + ]: 8 : if (!trigDesc || !trigDesc->trig_update_instead_row)
3266 [ + - + - ]: 4 : ereport(ERROR,
3267 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3268 : : errmsg("cannot update view \"%s\"",
3269 : : RelationGetRelationName(view)),
3270 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3271 : : errhint("To enable updating the view using MERGE, provide an INSTEAD OF UPDATE trigger."));
3272 : 4 : break;
3273 : 8 : case CMD_DELETE:
3274 [ + + + - ]: 8 : if (!trigDesc || !trigDesc->trig_delete_instead_row)
3275 [ + - + - ]: 8 : ereport(ERROR,
3276 : : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3277 : : errmsg("cannot delete from view \"%s\"",
3278 : : RelationGetRelationName(view)),
3279 : : detail ? errdetail_internal("%s", _(detail)) : 0,
3280 : : errhint("To enable deleting from the view using MERGE, provide an INSTEAD OF DELETE trigger."));
796 dean.a.rasheed@gmail 3281 :UBC 0 : break;
3282 : 0 : case CMD_NOTHING:
3283 : 0 : break;
3284 : 0 : default:
3285 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d", action->commandType);
3286 : : break;
3287 : : }
3288 : : }
3289 : 0 : break;
3290 : 0 : default:
3291 [ # # ]: 0 : elog(ERROR, "unrecognized CmdType: %d", (int) command);
3292 : : break;
3293 : : }
3294 : 0 : }
3295 : :
3296 : :
3297 : : /*
3298 : : * rewriteTargetView -
3299 : : * Attempt to rewrite a query where the target relation is a view, so that
3300 : : * the view's base relation becomes the target relation.
3301 : : *
3302 : : * Note that the base relation here may itself be a view, which may or may not
3303 : : * have INSTEAD OF triggers or rules to handle the update. That is handled by
3304 : : * the recursion in RewriteQuery.
3305 : : */
3306 : : static Query *
4896 tgl@sss.pgh.pa.us 3307 :CBC 2391 : rewriteTargetView(Query *parsetree, Relation view)
3308 : : {
3309 : : Query *viewquery;
3310 : : bool insert_or_update;
3311 : : const char *auto_update_detail;
3312 : : RangeTblRef *rtr;
3313 : : int base_rt_index;
3314 : : int new_rt_index;
3315 : : RangeTblEntry *base_rte;
3316 : : RangeTblEntry *view_rte;
3317 : : RangeTblEntry *new_rte;
3318 : : RTEPermissionInfo *base_perminfo;
3319 : : RTEPermissionInfo *view_perminfo;
3320 : : RTEPermissionInfo *new_perminfo;
3321 : : Relation base_rel;
3322 : : List *view_targetlist;
3323 : : ListCell *lc;
3324 : :
3325 : : /*
3326 : : * Get the Query from the view's ON SELECT rule. We're going to munge the
3327 : : * Query to change the view's base relation into the target relation,
3328 : : * along with various other changes along the way, so we need to make a
3329 : : * copy of it (get_view_query() returns a pointer into the relcache, so we
3330 : : * have to treat it as read-only).
3331 : : */
3788 sfrost@snowman.net 3332 : 2391 : viewquery = copyObject(get_view_query(view));
3333 : :
3334 : : /* Locate RTE and perminfo describing the view in the outer query */
654 tgl@sss.pgh.pa.us 3335 : 2391 : view_rte = rt_fetch(parsetree->resultRelation, parsetree->rtable);
3336 : 2391 : view_perminfo = getRTEPermissionInfo(parsetree->rteperminfos, view_rte);
3337 : :
3338 : : /*
3339 : : * Are we doing INSERT/UPDATE, or MERGE containing INSERT/UPDATE? If so,
3340 : : * various additional checks on the view columns need to be applied, and
3341 : : * any view CHECK OPTIONs need to be enforced.
3342 : : */
796 dean.a.rasheed@gmail 3343 : 2391 : insert_or_update =
3344 [ + + ]: 3922 : (parsetree->commandType == CMD_INSERT ||
3345 [ + + ]: 1531 : parsetree->commandType == CMD_UPDATE);
3346 : :
3347 [ + + ]: 2391 : if (parsetree->commandType == CMD_MERGE)
3348 : : {
3349 [ + - + + : 1284 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3350 : : {
3351 [ + + ]: 628 : if (action->commandType == CMD_INSERT ||
3352 [ + + ]: 556 : action->commandType == CMD_UPDATE)
3353 : : {
3354 : 536 : insert_or_update = true;
4896 tgl@sss.pgh.pa.us 3355 : 536 : break;
3356 : : }
3357 : : }
3358 : : }
3359 : :
3360 : : /* Check if the expansion of non-system views are restricted */
638 msawada@postgresql.o 3361 [ + + + - : 2391 : if (unlikely((restrict_nonsystem_relation_kind & RESTRICT_RELKIND_VIEW) != 0 &&
+ + ]
3362 : : RelationGetRelid(view) >= FirstNormalObjectId))
3363 [ + - ]: 4 : ereport(ERROR,
3364 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3365 : : errmsg("access to non-system view \"%s\" is restricted",
3366 : : RelationGetRelationName(view))));
3367 : :
3368 : : /*
3369 : : * The view must be updatable, else fail.
3370 : : *
3371 : : * If we are doing INSERT/UPDATE (or MERGE containing INSERT/UPDATE), we
3372 : : * also check that there is at least one updatable column.
3373 : : */
3374 : : auto_update_detail =
796 dean.a.rasheed@gmail 3375 : 2387 : view_query_is_auto_updatable(viewquery, insert_or_update);
3376 : :
3377 [ + + ]: 2387 : if (auto_update_detail)
3378 : 92 : error_view_not_updatable(view,
3379 : : parsetree->commandType,
3380 : : parsetree->mergeActionList,
3381 : : auto_update_detail);
3382 : :
3383 : : /*
3384 : : * For INSERT/UPDATE (or MERGE containing INSERT/UPDATE) the modified
3385 : : * columns must all be updatable.
3386 : : */
3387 [ + + ]: 2295 : if (insert_or_update)
3388 : : {
3389 : : Bitmapset *modified_cols;
3390 : : char *non_updatable_col;
3391 : :
3392 : : /*
3393 : : * Compute the set of modified columns as those listed in the result
3394 : : * RTE's insertedCols and/or updatedCols sets plus those that are
3395 : : * targets of the query's targetlist(s). We must consider the query's
3396 : : * targetlist because rewriteTargetListIU may have added additional
3397 : : * targetlist entries for view defaults, and these must also be
3398 : : * updatable. But rewriteTargetListIU can also remove entries if they
3399 : : * are DEFAULT markers and the column's default is NULL, so
3400 : : * considering only the targetlist would also be wrong.
3401 : : */
654 tgl@sss.pgh.pa.us 3402 : 2035 : modified_cols = bms_union(view_perminfo->insertedCols,
3403 : 2035 : view_perminfo->updatedCols);
3404 : :
4582 rhaas@postgresql.org 3405 [ + + + + : 4328 : foreach(lc, parsetree->targetList)
+ + ]
3406 : : {
3407 : 2293 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3408 : :
3409 [ + - ]: 2293 : if (!tle->resjunk)
3410 : 2293 : modified_cols = bms_add_member(modified_cols,
3240 tgl@sss.pgh.pa.us 3411 : 2293 : tle->resno - FirstLowInvalidHeapAttributeNumber);
3412 : : }
3413 : :
4015 andres@anarazel.de 3414 [ + + ]: 2035 : if (parsetree->onConflict)
3415 : : {
3416 [ + + + + : 280 : foreach(lc, parsetree->onConflict->onConflictSet)
+ + ]
3417 : : {
3418 : 108 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3419 : :
3420 [ + - ]: 108 : if (!tle->resjunk)
3421 : 108 : modified_cols = bms_add_member(modified_cols,
3240 tgl@sss.pgh.pa.us 3422 : 108 : tle->resno - FirstLowInvalidHeapAttributeNumber);
3423 : : }
3424 : : }
3425 : :
796 dean.a.rasheed@gmail 3426 [ + + + + : 4722 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3427 : : {
3428 [ + + ]: 652 : if (action->commandType == CMD_INSERT ||
3429 [ + + ]: 512 : action->commandType == CMD_UPDATE)
3430 : : {
3431 [ + - + + : 1964 : foreach_node(TargetEntry, tle, action->targetList)
+ + ]
3432 : : {
3433 [ + - ]: 756 : if (!tle->resjunk)
3434 : 756 : modified_cols = bms_add_member(modified_cols,
3435 : 756 : tle->resno - FirstLowInvalidHeapAttributeNumber);
3436 : : }
3437 : : }
3438 : : }
3439 : :
4582 rhaas@postgresql.org 3440 : 2035 : auto_update_detail = view_cols_are_auto_updatable(viewquery,
3441 : : modified_cols,
3442 : : NULL,
3443 : : &non_updatable_col);
3444 [ + + ]: 2035 : if (auto_update_detail)
3445 : : {
3446 : : /*
3447 : : * This is a different error, caused by an attempt to update a
3448 : : * non-updatable column in an otherwise updatable view.
3449 : : */
3450 [ + + + - ]: 80 : switch (parsetree->commandType)
3451 : : {
3452 : 48 : case CMD_INSERT:
3453 [ + - ]: 48 : ereport(ERROR,
3454 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3455 : : errmsg("cannot insert into column \"%s\" of view \"%s\"",
3456 : : non_updatable_col,
3457 : : RelationGetRelationName(view)),
3458 : : errdetail_internal("%s", _(auto_update_detail))));
3459 : : break;
3460 : 28 : case CMD_UPDATE:
3461 [ + - ]: 28 : ereport(ERROR,
3462 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3463 : : errmsg("cannot update column \"%s\" of view \"%s\"",
3464 : : non_updatable_col,
3465 : : RelationGetRelationName(view)),
3466 : : errdetail_internal("%s", _(auto_update_detail))));
3467 : : break;
796 dean.a.rasheed@gmail 3468 : 4 : case CMD_MERGE:
3469 [ + - ]: 4 : ereport(ERROR,
3470 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3471 : : errmsg("cannot merge into column \"%s\" of view \"%s\"",
3472 : : non_updatable_col,
3473 : : RelationGetRelationName(view)),
3474 : : errdetail_internal("%s", _(auto_update_detail))));
3475 : : break;
4582 rhaas@postgresql.org 3476 :UBC 0 : default:
3477 [ # # ]: 0 : elog(ERROR, "unrecognized CmdType: %d",
3478 : : (int) parsetree->commandType);
3479 : : break;
3480 : : }
3481 : : }
3482 : : }
3483 : :
3484 : : /*
3485 : : * For MERGE, there must not be any INSTEAD OF triggers on an otherwise
3486 : : * updatable view. The caller already checked that there isn't a full set
3487 : : * of INSTEAD OF triggers, so this is to guard against having a partial
3488 : : * set (mixing auto-update and trigger-update actions in a single command
3489 : : * isn't supported).
3490 : : */
796 dean.a.rasheed@gmail 3491 [ + + ]:CBC 2215 : if (parsetree->commandType == CMD_MERGE)
3492 : : {
3493 [ + - + + : 1832 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3494 : : {
3495 [ + - + + ]: 1392 : if (action->commandType != CMD_NOTHING &&
3496 : 696 : view_has_instead_trigger(view, action->commandType, NIL))
3497 [ + - ]: 4 : ereport(ERROR,
3498 : : errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3499 : : errmsg("cannot merge into view \"%s\"",
3500 : : RelationGetRelationName(view)),
3501 : : errdetail("MERGE is not supported for views with INSTEAD OF triggers for some actions but not all."),
3502 : : errhint("To enable merging into the view, either provide a full set of INSTEAD OF triggers or drop the existing INSTEAD OF triggers."));
3503 : : }
3504 : : }
3505 : :
3506 : : /*
3507 : : * If we get here, view_query_is_auto_updatable() has verified that the
3508 : : * view contains a single base relation.
3509 : : */
4896 tgl@sss.pgh.pa.us 3510 [ - + ]: 2211 : Assert(list_length(viewquery->jointree->fromlist) == 1);
3312 3511 : 2211 : rtr = linitial_node(RangeTblRef, viewquery->jointree->fromlist);
3512 : :
4896 3513 : 2211 : base_rt_index = rtr->rtindex;
3514 : 2211 : base_rte = rt_fetch(base_rt_index, viewquery->rtable);
3515 [ - + ]: 2211 : Assert(base_rte->rtekind == RTE_RELATION);
1246 alvherre@alvh.no-ip. 3516 : 2211 : base_perminfo = getRTEPermissionInfo(viewquery->rteperminfos, base_rte);
3517 : :
3518 : : /*
3519 : : * Up to now, the base relation hasn't been touched at all in our query.
3520 : : * We need to acquire lock on it before we try to do anything with it.
3521 : : * (The subsequent recursive call of RewriteQuery will suppose that we
3522 : : * already have the right lock!) Since it will become the query target
3523 : : * relation, RowExclusiveLock is always the right thing.
3524 : : */
55 peter@eisentraut.org 3525 :GNC 2211 : base_rel = relation_open(base_rte->relid, RowExclusiveLock);
3526 : :
3527 : : /*
3528 : : * While we have the relation open, update the RTE's relkind, just in case
3529 : : * it changed since this view was made (cf. AcquireRewriteLocks).
3530 : : */
4896 tgl@sss.pgh.pa.us 3531 :CBC 2211 : base_rte->relkind = base_rel->rd_rel->relkind;
3532 : :
3533 : : /*
3534 : : * If the view query contains any sublink subqueries then we need to also
3535 : : * acquire locks on any relations they refer to. We know that there won't
3536 : : * be any subqueries in the range table or CTEs, so we can skip those, as
3537 : : * in AcquireRewriteLocks.
3538 : : */
3892 sfrost@snowman.net 3539 [ + + ]: 2211 : if (viewquery->hasSubLinks)
3540 : : {
3541 : : acquireLocksOnSubLinks_context context;
3542 : :
3543 : 172 : context.for_execute = true;
3544 : 172 : query_tree_walker(viewquery, acquireLocksOnSubLinks, &context,
3545 : : QTW_IGNORE_RC_SUBQUERIES);
3546 : : }
3547 : :
3548 : : /*
3549 : : * Create a new target RTE describing the base relation, and add it to the
3550 : : * outer query's rangetable. (What's happening in the next few steps is
3551 : : * very much like what the planner would do to "pull up" the view into the
3552 : : * outer query. Perhaps someday we should refactor things enough so that
3553 : : * we can share code with the planner.)
3554 : : *
3555 : : * Be sure to set rellockmode to the correct thing for the target table.
3556 : : * Since we copied the whole viewquery above, we can just scribble on
3557 : : * base_rte instead of copying it.
3558 : : */
2774 tgl@sss.pgh.pa.us 3559 : 2211 : new_rte = base_rte;
3560 : 2211 : new_rte->rellockmode = RowExclusiveLock;
3561 : :
4896 3562 : 2211 : parsetree->rtable = lappend(parsetree->rtable, new_rte);
3563 : 2211 : new_rt_index = list_length(parsetree->rtable);
3564 : :
3565 : : /*
3566 : : * INSERTs never inherit. For UPDATE/DELETE/MERGE, we use the view
3567 : : * query's inheritance flag for the base relation.
3568 : : */
4689 3569 [ + + ]: 2211 : if (parsetree->commandType == CMD_INSERT)
3570 : 796 : new_rte->inh = false;
3571 : :
3572 : : /*
3573 : : * Adjust the view's targetlist Vars to reference the new target RTE, ie
3574 : : * make their varnos be new_rt_index instead of base_rt_index. There can
3575 : : * be no Vars for other rels in the tlist, so this is sufficient to pull
3576 : : * up the tlist expressions for use in the outer query. The tlist will
3577 : : * provide the replacement expressions used by ReplaceVarsFromTargetList
3578 : : * below.
3579 : : */
3788 sfrost@snowman.net 3580 : 2211 : view_targetlist = viewquery->targetList;
3581 : :
4896 tgl@sss.pgh.pa.us 3582 : 2211 : ChangeVarNodes((Node *) view_targetlist,
3583 : : base_rt_index,
3584 : : new_rt_index,
3585 : : 0);
3586 : :
3587 : : /*
3588 : : * If the view has "security_invoker" set, mark the new target relation
3589 : : * for the permissions checks that we want to enforce against the query
3590 : : * caller. Otherwise we want to enforce them against the view owner.
3591 : : *
3592 : : * At the relation level, require the same INSERT/UPDATE/DELETE
3593 : : * permissions that the query caller needs against the view. We drop the
3594 : : * ACL_SELECT bit that is presumably in new_perminfo->requiredPerms
3595 : : * initially.
3596 : : *
3597 : : * Note: the original view's RTEPermissionInfo remains in the query's
3598 : : * rteperminfos so that the executor still performs appropriate
3599 : : * permissions checks for the query caller's use of the view.
3600 : : *
3601 : : * Disregard the perminfo in viewquery->rteperminfos that the base_rte
3602 : : * would currently be pointing at, because we'd like it to point now to a
3603 : : * new one that will be filled below. Must set perminfoindex to 0 to not
3604 : : * trip over the Assert in addRTEPermissionInfo().
3605 : : */
1246 alvherre@alvh.no-ip. 3606 : 2211 : new_rte->perminfoindex = 0;
3607 : 2211 : new_perminfo = addRTEPermissionInfo(&parsetree->rteperminfos, new_rte);
1505 dean.a.rasheed@gmail 3608 [ - + + + : 2211 : if (RelationHasSecurityInvoker(view))
+ + ]
1246 alvherre@alvh.no-ip. 3609 : 324 : new_perminfo->checkAsUser = InvalidOid;
3610 : : else
3611 : 1887 : new_perminfo->checkAsUser = view->rd_rel->relowner;
3612 : 2211 : new_perminfo->requiredPerms = view_perminfo->requiredPerms;
3613 : :
3614 : : /*
3615 : : * Now for the per-column permissions bits.
3616 : : *
3617 : : * Initially, new_perminfo (base_perminfo) contains selectedCols
3618 : : * permission check bits for all base-rel columns referenced by the view,
3619 : : * but since the view is a SELECT query its insertedCols/updatedCols is
3620 : : * empty. We set insertedCols and updatedCols to include all the columns
3621 : : * the outer query is trying to modify, adjusting the column numbers as
3622 : : * needed. But we leave selectedCols as-is, so the view owner must have
3623 : : * read permission for all columns used in the view definition, even if
3624 : : * some of them are not read by the outer query. We could try to limit
3625 : : * selectedCols to only columns used in the transformed query, but that
3626 : : * does not correspond to what happens in ordinary SELECT usage of a view:
3627 : : * all referenced columns must have read permission, even if optimization
3628 : : * finds that some of them can be discarded during query transformation.
3629 : : * The flattening we're doing here is an optional optimization, too. (If
3630 : : * you are unpersuaded and want to change this, note that applying
3631 : : * adjust_view_column_set to view_perminfo->selectedCols is clearly *not*
3632 : : * the right answer, since that neglects base-rel columns used in the
3633 : : * view's WHERE quals.)
3634 : : *
3635 : : * This step needs the modified view targetlist, so we have to do things
3636 : : * in this order.
3637 : : */
3638 [ + - - + ]: 2211 : Assert(bms_is_empty(new_perminfo->insertedCols) &&
3639 : : bms_is_empty(new_perminfo->updatedCols));
3640 : :
3641 : 2211 : new_perminfo->selectedCols = base_perminfo->selectedCols;
3642 : :
3643 : 2211 : new_perminfo->insertedCols =
3644 : 2211 : adjust_view_column_set(view_perminfo->insertedCols, view_targetlist);
3645 : :
3646 : 2211 : new_perminfo->updatedCols =
3647 : 2211 : adjust_view_column_set(view_perminfo->updatedCols, view_targetlist);
3648 : :
3649 : : /*
3650 : : * Move any security barrier quals from the view RTE onto the new target
3651 : : * RTE. Any such quals should now apply to the new target RTE and will
3652 : : * not reference the original view RTE in the rewritten query.
3653 : : */
4406 sfrost@snowman.net 3654 : 2211 : new_rte->securityQuals = view_rte->securityQuals;
3655 : 2211 : view_rte->securityQuals = NIL;
3656 : :
3657 : : /*
3658 : : * Now update all Vars in the outer query that reference the view to
3659 : : * reference the appropriate column of the base relation instead.
3660 : : */
3661 : : parsetree = (Query *)
4896 tgl@sss.pgh.pa.us 3662 : 2211 : ReplaceVarsFromTargetList((Node *) parsetree,
3663 : : parsetree->resultRelation,
3664 : : 0,
3665 : : view_rte,
3666 : : view_targetlist,
3667 : : new_rt_index,
3668 : : REPLACEVARS_REPORT_ERROR,
3669 : : 0,
3670 : : NULL);
3671 : :
3672 : : /*
3673 : : * Update all other RTI references in the query that point to the view
3674 : : * (for example, parsetree->resultRelation itself) to point to the new
3675 : : * base relation instead. Vars will not be affected since none of them
3676 : : * reference parsetree->resultRelation any longer.
3677 : : */
3678 : 2211 : ChangeVarNodes((Node *) parsetree,
3679 : : parsetree->resultRelation,
3680 : : new_rt_index,
3681 : : 0);
3682 [ - + ]: 2211 : Assert(parsetree->resultRelation == new_rt_index);
3683 : :
3684 : : /*
3685 : : * For INSERT/UPDATE we must also update resnos in the targetlist to refer
3686 : : * to columns of the base relation, since those indicate the target
3687 : : * columns to be affected. Similarly, for MERGE we must update the resnos
3688 : : * in the merge action targetlists of any INSERT/UPDATE actions.
3689 : : *
3690 : : * Note that this destroys the resno ordering of the targetlists, but that
3691 : : * will be fixed when we recurse through RewriteQuery, which will invoke
3692 : : * rewriteTargetListIU again on the updated targetlists.
3693 : : */
3694 [ + + ]: 2211 : if (parsetree->commandType != CMD_DELETE)
3695 : : {
3696 [ + + + + : 4148 : foreach(lc, parsetree->targetList)
+ + ]
3697 : : {
3698 : 2141 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3699 : : TargetEntry *view_tle;
3700 : :
3701 [ - + ]: 2141 : if (tle->resjunk)
4896 tgl@sss.pgh.pa.us 3702 :UBC 0 : continue;
3703 : :
4896 tgl@sss.pgh.pa.us 3704 :CBC 2141 : view_tle = get_tle_by_resno(view_targetlist, tle->resno);
3705 [ + - + - : 2141 : if (view_tle != NULL && !view_tle->resjunk && IsA(view_tle->expr, Var))
+ - ]
3706 : 2141 : tle->resno = ((Var *) view_tle->expr)->varattno;
3707 : : else
4896 tgl@sss.pgh.pa.us 3708 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3709 : : tle->resno);
3710 : : }
3711 : :
796 dean.a.rasheed@gmail 3712 [ + + + + :CBC 4706 : foreach_node(MergeAction, action, parsetree->mergeActionList)
+ + ]
3713 : : {
3714 [ + + ]: 692 : if (action->commandType == CMD_INSERT ||
3715 [ + + ]: 560 : action->commandType == CMD_UPDATE)
3716 : : {
3717 [ + - + + : 1904 : foreach_node(TargetEntry, tle, action->targetList)
+ + ]
3718 : : {
3719 : : TargetEntry *view_tle;
3720 : :
3721 [ - + ]: 728 : if (tle->resjunk)
796 dean.a.rasheed@gmail 3722 :UBC 0 : continue;
3723 : :
796 dean.a.rasheed@gmail 3724 :CBC 728 : view_tle = get_tle_by_resno(view_targetlist, tle->resno);
3725 [ + - + - : 728 : if (view_tle != NULL && !view_tle->resjunk && IsA(view_tle->expr, Var))
+ - ]
3726 : 728 : tle->resno = ((Var *) view_tle->expr)->varattno;
3727 : : else
796 dean.a.rasheed@gmail 3728 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3729 : : tle->resno);
3730 : : }
3731 : : }
3732 : : }
3733 : : }
3734 : :
3735 : : /*
3736 : : * For INSERT .. ON CONFLICT .. DO SELECT/UPDATE, we must also update
3737 : : * assorted stuff in the onConflict data structure.
3738 : : */
2831 tgl@sss.pgh.pa.us 3739 [ + + ]:CBC 2211 : if (parsetree->onConflict &&
82 dean.a.rasheed@gmail 3740 [ + + ]:GNC 164 : (parsetree->onConflict->action == ONCONFLICT_UPDATE ||
3741 [ + + ]: 64 : parsetree->onConflict->action == ONCONFLICT_SELECT))
3742 : : {
3743 : : Index old_exclRelIndex,
3744 : : new_exclRelIndex;
3745 : : ParseNamespaceItem *new_exclNSItem;
3746 : : RangeTblEntry *new_exclRte;
3747 : : List *tmp_tlist;
3748 : :
3749 : : /*
3750 : : * For ON CONFLICT DO UPDATE, update the resnos in the auxiliary
3751 : : * UPDATE targetlist to refer to columns of the base relation.
3752 : : */
2831 tgl@sss.pgh.pa.us 3753 [ + + + + :CBC 248 : foreach(lc, parsetree->onConflict->onConflictSet)
+ + ]
3754 : : {
3755 : 100 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3756 : : TargetEntry *view_tle;
3757 : :
3758 [ - + ]: 100 : if (tle->resjunk)
2831 tgl@sss.pgh.pa.us 3759 :UBC 0 : continue;
3760 : :
2831 tgl@sss.pgh.pa.us 3761 :CBC 100 : view_tle = get_tle_by_resno(view_targetlist, tle->resno);
3762 [ + - + - : 100 : if (view_tle != NULL && !view_tle->resjunk && IsA(view_tle->expr, Var))
+ - ]
3763 : 100 : tle->resno = ((Var *) view_tle->expr)->varattno;
3764 : : else
2831 tgl@sss.pgh.pa.us 3765 [ # # ]:UBC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3766 : : tle->resno);
3767 : : }
3768 : :
3769 : : /*
3770 : : * Create a new RTE for the EXCLUDED pseudo-relation, using the
3771 : : * query's new base rel (which may well have a different column list
3772 : : * from the view, hence we need a new column alias list). This should
3773 : : * match transformOnConflictClause. In particular, note that the
3774 : : * relkind is set to composite to signal that we're not dealing with
3775 : : * an actual relation.
3776 : : */
2831 tgl@sss.pgh.pa.us 3777 :CBC 148 : old_exclRelIndex = parsetree->onConflict->exclRelIndex;
3778 : :
2315 3779 : 148 : new_exclNSItem = addRangeTableEntryForRelation(make_parsestate(NULL),
3780 : : base_rel,
3781 : : RowExclusiveLock,
3782 : : makeAlias("excluded", NIL),
3783 : : false, false);
3784 : 148 : new_exclRte = new_exclNSItem->p_rte;
2831 3785 : 148 : new_exclRte->relkind = RELKIND_COMPOSITE_TYPE;
3786 : : /* Ignore the RTEPermissionInfo that would've been added. */
1246 alvherre@alvh.no-ip. 3787 : 148 : new_exclRte->perminfoindex = 0;
3788 : :
2831 tgl@sss.pgh.pa.us 3789 : 148 : parsetree->rtable = lappend(parsetree->rtable, new_exclRte);
3790 : 296 : new_exclRelIndex = parsetree->onConflict->exclRelIndex =
3791 : 148 : list_length(parsetree->rtable);
3792 : :
3793 : : /*
3794 : : * Replace the targetlist for the EXCLUDED pseudo-relation with a new
3795 : : * one, representing the columns from the new base relation.
3796 : : */
3797 : 296 : parsetree->onConflict->exclRelTlist =
3798 : 148 : BuildOnConflictExcludedTargetlist(base_rel, new_exclRelIndex);
3799 : :
3800 : : /*
3801 : : * Update all Vars in the ON CONFLICT clause that refer to the old
3802 : : * EXCLUDED pseudo-relation. We want to use the column mappings
3803 : : * defined in the view targetlist, but we need the outputs to refer to
3804 : : * the new EXCLUDED pseudo-relation rather than the new target RTE.
3805 : : * Also notice that "EXCLUDED.*" will be expanded using the view's
3806 : : * rowtype, which seems correct.
3807 : : */
3808 : 148 : tmp_tlist = copyObject(view_targetlist);
3809 : :
3810 : 148 : ChangeVarNodes((Node *) tmp_tlist, new_rt_index,
3811 : : new_exclRelIndex, 0);
3812 : :
3813 : 148 : parsetree->onConflict = (OnConflictExpr *)
3814 : 148 : ReplaceVarsFromTargetList((Node *) parsetree->onConflict,
3815 : : old_exclRelIndex,
3816 : : 0,
3817 : : view_rte,
3818 : : tmp_tlist,
3819 : : new_rt_index,
3820 : : REPLACEVARS_REPORT_ERROR,
3821 : : 0,
3822 : : &parsetree->hasSubLinks);
3823 : : }
3824 : :
34 peter@eisentraut.org 3825 [ + + + + ]:GNC 2211 : if (parsetree->forPortionOf && parsetree->commandType == CMD_UPDATE)
3826 : : {
3827 : : /*
3828 : : * Like the INSERT/UPDATE code above, update the resnos in the
3829 : : * auxiliary UPDATE targetlist to refer to columns of the base
3830 : : * relation.
3831 : : */
3832 [ + - + + : 8 : foreach(lc, parsetree->forPortionOf->rangeTargetList)
+ + ]
3833 : : {
3834 : 4 : TargetEntry *tle = (TargetEntry *) lfirst(lc);
3835 : : TargetEntry *view_tle;
3836 : :
3837 [ - + ]: 4 : if (tle->resjunk)
34 peter@eisentraut.org 3838 :UNC 0 : continue;
3839 : :
34 peter@eisentraut.org 3840 :GNC 4 : view_tle = get_tle_by_resno(view_targetlist, tle->resno);
3841 [ + - + - : 4 : if (view_tle != NULL && !view_tle->resjunk && IsA(view_tle->expr, Var))
+ - ]
3842 : 4 : tle->resno = ((Var *) view_tle->expr)->varattno;
3843 : : else
34 peter@eisentraut.org 3844 [ # # ]:UNC 0 : elog(ERROR, "attribute number %d not found in view targetlist",
3845 : : tle->resno);
3846 : : }
3847 : : }
3848 : :
3849 : : /*
3850 : : * For UPDATE/DELETE/MERGE, pull up any WHERE quals from the view. We
3851 : : * know that any Vars in the quals must reference the one base relation,
3852 : : * so we need only adjust their varnos to reference the new target (just
3853 : : * the same as we did with the view targetlist).
3854 : : *
3855 : : * If it's a security-barrier view, its WHERE quals must be applied before
3856 : : * quals from the outer query, so we attach them to the RTE as security
3857 : : * barrier quals rather than adding them to the main WHERE clause.
3858 : : *
3859 : : * For INSERT, the view's quals can be ignored in the main query.
3860 : : */
4896 tgl@sss.pgh.pa.us 3861 [ + + ]:CBC 2211 : if (parsetree->commandType != CMD_INSERT &&
3862 [ + + ]: 1415 : viewquery->jointree->quals != NULL)
3863 : : {
3788 sfrost@snowman.net 3864 : 503 : Node *viewqual = (Node *) viewquery->jointree->quals;
3865 : :
3866 : : /*
3867 : : * Even though we copied viewquery already at the top of this
3868 : : * function, we must duplicate the viewqual again here, because we may
3869 : : * need to use the quals again below for a WithCheckOption clause.
3870 : : */
3780 tgl@sss.pgh.pa.us 3871 : 503 : viewqual = copyObject(viewqual);
3872 : :
4896 3873 : 503 : ChangeVarNodes(viewqual, base_rt_index, new_rt_index, 0);
3874 : :
4406 sfrost@snowman.net 3875 [ - + + + : 503 : if (RelationIsSecurityView(view))
+ + ]
3876 : : {
3877 : : /*
3878 : : * The view's quals go in front of existing barrier quals: those
3879 : : * would have come from an outer level of security-barrier view,
3880 : : * and so must get evaluated later.
3881 : : *
3882 : : * Note: the parsetree has been mutated, so the new_rte pointer is
3883 : : * stale and needs to be re-computed.
3884 : : */
3885 : 156 : new_rte = rt_fetch(new_rt_index, parsetree->rtable);
3886 : 156 : new_rte->securityQuals = lcons(viewqual, new_rte->securityQuals);
3887 : :
3888 : : /*
3889 : : * Do not set parsetree->hasRowSecurity, because these aren't RLS
3890 : : * conditions (they aren't affected by enabling/disabling RLS).
3891 : : */
3892 : :
3893 : : /*
3894 : : * Make sure that the query is marked correctly if the added qual
3895 : : * has sublinks.
3896 : : */
3897 [ + + ]: 156 : if (!parsetree->hasSubLinks)
3898 : 140 : parsetree->hasSubLinks = checkExprHasSubLink(viewqual);
3899 : : }
3900 : : else
154 peter@eisentraut.org 3901 :GNC 347 : AddQual(parsetree, viewqual);
3902 : : }
3903 : :
3904 : : /*
3905 : : * For INSERT/UPDATE (or MERGE containing INSERT/UPDATE), if the view has
3906 : : * the WITH CHECK OPTION, or any parent view specified WITH CASCADED CHECK
3907 : : * OPTION, add the quals from the view to the query's withCheckOptions
3908 : : * list.
3909 : : */
796 dean.a.rasheed@gmail 3910 [ + + ]:CBC 2211 : if (insert_or_update)
3911 : : {
4674 sfrost@snowman.net 3912 [ - + + + : 1951 : bool has_wco = RelationHasCheckOption(view);
+ + ]
3913 [ - + + + : 1951 : bool cascaded = RelationHasCascadedCheckOption(view);
+ + ]
3914 : :
3915 : : /*
3916 : : * If the parent view has a cascaded check option, treat this view as
3917 : : * if it also had a cascaded check option.
3918 : : *
3919 : : * New WithCheckOptions are added to the start of the list, so if
3920 : : * there is a cascaded check option, it will be the first item in the
3921 : : * list.
3922 : : */
3923 [ + + ]: 1951 : if (parsetree->withCheckOptions != NIL)
3924 : : {
3925 : 76 : WithCheckOption *parent_wco =
1082 tgl@sss.pgh.pa.us 3926 : 76 : (WithCheckOption *) linitial(parsetree->withCheckOptions);
3927 : :
4674 sfrost@snowman.net 3928 [ + + ]: 76 : if (parent_wco->cascaded)
3929 : : {
3930 : 60 : has_wco = true;
3931 : 60 : cascaded = true;
3932 : : }
3933 : : }
3934 : :
3935 : : /*
3936 : : * Add the new WithCheckOption to the start of the list, so that
3937 : : * checks on inner views are run before checks on outer views, as
3938 : : * required by the SQL standard.
3939 : : *
3940 : : * If the new check is CASCADED, we need to add it even if this view
3941 : : * has no quals, since there may be quals on child views. A LOCAL
3942 : : * check can be omitted if this view has no quals.
3943 : : */
3944 [ + + + + : 1951 : if (has_wco && (cascaded || viewquery->jointree->quals != NULL))
+ - ]
3945 : : {
3946 : : WithCheckOption *wco;
3947 : :
3948 : 431 : wco = makeNode(WithCheckOption);
4029 3949 : 431 : wco->kind = WCO_VIEW_CHECK;
3950 : 431 : wco->relname = pstrdup(RelationGetRelationName(view));
3885 3951 : 431 : wco->polname = NULL;
4674 3952 : 431 : wco->qual = NULL;
3953 : 431 : wco->cascaded = cascaded;
3954 : :
3955 : 431 : parsetree->withCheckOptions = lcons(wco,
3956 : : parsetree->withCheckOptions);
3957 : :
3958 [ + + ]: 431 : if (viewquery->jointree->quals != NULL)
3959 : : {
3788 3960 : 391 : wco->qual = (Node *) viewquery->jointree->quals;
4674 3961 : 391 : ChangeVarNodes(wco->qual, base_rt_index, new_rt_index, 0);
3962 : :
3963 : : /*
3964 : : * For INSERT, make sure that the query is marked correctly if
3965 : : * the added qual has sublinks. This can be skipped for
3966 : : * UPDATE/MERGE, since the same qual will have already been
3967 : : * added above, and the check will already have been done.
3968 : : */
3969 [ + + ]: 391 : if (!parsetree->hasSubLinks &&
796 dean.a.rasheed@gmail 3970 [ + + ]: 327 : parsetree->commandType == CMD_INSERT)
4674 sfrost@snowman.net 3971 : 204 : parsetree->hasSubLinks = checkExprHasSubLink(wco->qual);
3972 : : }
3973 : : }
3974 : : }
3975 : :
2661 andres@anarazel.de 3976 : 2211 : table_close(base_rel, NoLock);
3977 : :
4896 tgl@sss.pgh.pa.us 3978 : 2211 : return parsetree;
3979 : : }
3980 : :
3981 : :
3982 : : /*
3983 : : * RewriteQuery -
3984 : : * rewrites the query and apply the rules again on the queries rewritten
3985 : : *
3986 : : * rewrite_events is a list of open query-rewrite actions, so we can detect
3987 : : * infinite recursion.
3988 : : *
3989 : : * orig_rt_length is the length of the originating query's rtable, for product
3990 : : * queries created by fireRules(), and 0 otherwise. This is used to skip any
3991 : : * already-processed VALUES RTEs from the original query.
3992 : : *
3993 : : * num_ctes_processed is the number of CTEs at the end of the query's cteList
3994 : : * that have already been rewritten, and must not be rewritten again.
3995 : : */
3996 : : static List *
157 dean.a.rasheed@gmail 3997 : 291169 : RewriteQuery(Query *parsetree, List *rewrite_events, int orig_rt_length,
3998 : : int num_ctes_processed)
3999 : : {
8470 tgl@sss.pgh.pa.us 4000 : 291169 : CmdType event = parsetree->commandType;
4001 : 291169 : bool instead = false;
7185 4002 : 291169 : bool returning = false;
4015 andres@anarazel.de 4003 : 291169 : bool updatableview = false;
8470 tgl@sss.pgh.pa.us 4004 : 291169 : Query *qual_product = NULL;
4005 : 291169 : List *rewritten = NIL;
4006 : : ListCell *lc1;
4007 : :
4008 : : /*
4009 : : * First, recursively process any insert/update/delete/merge statements in
4010 : : * WITH clauses. (We have to do this first because the WITH clauses may
4011 : : * get copied into rule actions below.)
4012 : : *
4013 : : * Any new WITH clauses from rule actions are processed when we recurse
4014 : : * into product queries below. However, when recursing, we must take care
4015 : : * to avoid rewriting a CTE query more than once (because expanding
4016 : : * generated columns in the targetlist more than once would fail). Since
4017 : : * new CTEs from product queries are added to the start of the list (see
4018 : : * rewriteRuleAction), we just skip the last num_ctes_processed items.
4019 : : */
5446 4020 [ + + + + : 293479 : foreach(lc1, parsetree->cteList)
+ + ]
4021 : : {
3312 4022 : 2358 : CommonTableExpr *cte = lfirst_node(CommonTableExpr, lc1);
3360 peter_e@gmx.net 4023 : 2358 : Query *ctequery = castNode(Query, cte->ctequery);
157 dean.a.rasheed@gmail 4024 : 2358 : int i = foreach_current_index(lc1);
4025 : : List *newstuff;
4026 : :
4027 : : /* Skip already-processed CTEs at the end of the list */
4028 [ + + ]: 2358 : if (i >= list_length(parsetree->cteList) - num_ctes_processed)
4029 : 28 : break;
4030 : :
5446 tgl@sss.pgh.pa.us 4031 [ + + ]: 2330 : if (ctequery->commandType == CMD_SELECT)
4032 : 2080 : continue;
4033 : :
157 dean.a.rasheed@gmail 4034 : 250 : newstuff = RewriteQuery(ctequery, rewrite_events, 0, 0);
4035 : :
4036 : : /*
4037 : : * Currently we can only handle unconditional, single-statement DO
4038 : : * INSTEAD rules correctly; we have to get exactly one non-utility
4039 : : * Query out of the rewrite operation to stuff back into the CTE node.
4040 : : */
5446 tgl@sss.pgh.pa.us 4041 [ + + ]: 250 : if (list_length(newstuff) == 1)
4042 : : {
4043 : : /* Must check it's not a utility command */
3312 4044 : 234 : ctequery = linitial_node(Query, newstuff);
1761 4045 [ + - ]: 234 : if (!(ctequery->commandType == CMD_SELECT ||
4046 [ + + ]: 234 : ctequery->commandType == CMD_UPDATE ||
4047 [ + + ]: 169 : ctequery->commandType == CMD_INSERT ||
779 dean.a.rasheed@gmail 4048 [ + + ]: 54 : ctequery->commandType == CMD_DELETE ||
4049 [ + + ]: 22 : ctequery->commandType == CMD_MERGE))
4050 : : {
4051 : : /*
4052 : : * Currently it could only be NOTIFY; this error message will
4053 : : * need work if we ever allow other utility commands in rules.
4054 : : */
1761 tgl@sss.pgh.pa.us 4055 [ + - ]: 4 : ereport(ERROR,
4056 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4057 : : errmsg("DO INSTEAD NOTIFY rules are not supported for data-modifying statements in WITH")));
4058 : : }
4059 : : /* WITH queries should never be canSetTag */
5446 4060 [ - + ]: 230 : Assert(!ctequery->canSetTag);
4061 : : /* Push the single Query back into the CTE node */
4062 : 230 : cte->ctequery = (Node *) ctequery;
4063 : : }
4064 [ + + ]: 16 : else if (newstuff == NIL)
4065 : : {
4066 [ + - ]: 4 : ereport(ERROR,
4067 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4068 : : errmsg("DO INSTEAD NOTHING rules are not supported for data-modifying statements in WITH")));
4069 : : }
4070 : : else
4071 : : {
4072 : : ListCell *lc2;
4073 : :
4074 : : /* examine queries to determine which error message to issue */
4075 [ + - + + : 28 : foreach(lc2, newstuff)
+ + ]
4076 : : {
4077 : 24 : Query *q = (Query *) lfirst(lc2);
4078 : :
4079 [ + + ]: 24 : if (q->querySource == QSRC_QUAL_INSTEAD_RULE)
4080 [ + - ]: 4 : ereport(ERROR,
4081 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4082 : : errmsg("conditional DO INSTEAD rules are not supported for data-modifying statements in WITH")));
4083 [ + + ]: 20 : if (q->querySource == QSRC_NON_INSTEAD_RULE)
4084 [ + - ]: 4 : ereport(ERROR,
4085 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4086 : : errmsg("DO ALSO rules are not supported for data-modifying statements in WITH")));
4087 : : }
4088 : :
4089 [ + - ]: 4 : ereport(ERROR,
4090 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4091 : : errmsg("multi-statement DO INSTEAD rules are not supported for data-modifying statements in WITH")));
4092 : : }
4093 : : }
157 dean.a.rasheed@gmail 4094 : 291149 : num_ctes_processed = list_length(parsetree->cteList);
4095 : :
4096 : : /*
4097 : : * If the statement is an insert, update, delete, or merge, adjust its
4098 : : * targetlist as needed, and then fire INSERT/UPDATE/DELETE rules on it.
4099 : : *
4100 : : * SELECT rules are handled later when we have all the queries that should
4101 : : * get executed. Also, utilities aren't rewritten at all (do we still
4102 : : * need that check?)
4103 : : */
8470 tgl@sss.pgh.pa.us 4104 [ + + + + ]: 291149 : if (event != CMD_SELECT && event != CMD_UTILITY)
4105 : : {
4106 : : int result_relation;
4107 : : RangeTblEntry *rt_entry;
4108 : : Relation rt_entry_relation;
4109 : : List *locks;
4110 : : int product_orig_rt_length;
4111 : : List *product_queries;
4015 andres@anarazel.de 4112 : 56688 : bool hasUpdate = false;
2631 dean.a.rasheed@gmail 4113 : 56688 : int values_rte_index = 0;
4114 : 56688 : bool defaults_remaining = false;
4115 : :
8470 tgl@sss.pgh.pa.us 4116 : 56688 : result_relation = parsetree->resultRelation;
4117 [ - + ]: 56688 : Assert(result_relation != 0);
4118 : 56688 : rt_entry = rt_fetch(result_relation, parsetree->rtable);
4119 [ - + ]: 56688 : Assert(rt_entry->rtekind == RTE_RELATION);
4120 : :
4121 : : /*
4122 : : * We can use NoLock here since either the parser or
4123 : : * AcquireRewriteLocks should have locked the rel already.
4124 : : */
55 peter@eisentraut.org 4125 :GNC 56688 : rt_entry_relation = relation_open(rt_entry->relid, NoLock);
4126 : :
4127 : : /*
4128 : : * Rewrite the targetlist as needed for the command type.
4129 : : */
5686 tgl@sss.pgh.pa.us 4130 [ + + ]:CBC 56688 : if (event == CMD_INSERT)
4131 : : {
4132 : : ListCell *lc2;
7216 mail@joeconway.com 4133 : 41559 : RangeTblEntry *values_rte = NULL;
4134 : :
4135 : : /*
4136 : : * Test if it's a multi-row INSERT ... VALUES (...), (...), ... by
4137 : : * looking for a VALUES RTE in the fromlist. For product queries,
4138 : : * we must ignore any already-processed VALUES RTEs from the
4139 : : * original query. These appear at the start of the rangetable.
4140 : : */
1249 dean.a.rasheed@gmail 4141 [ + + + + : 49592 : foreach(lc2, parsetree->jointree->fromlist)
+ + ]
4142 : : {
4143 : 8033 : RangeTblRef *rtr = (RangeTblRef *) lfirst(lc2);
4144 : :
4145 [ + - + + ]: 8033 : if (IsA(rtr, RangeTblRef) && rtr->rtindex > orig_rt_length)
4146 : : {
7216 mail@joeconway.com 4147 : 7801 : RangeTblEntry *rte = rt_fetch(rtr->rtindex,
4148 : : parsetree->rtable);
4149 : :
4150 [ + + ]: 7801 : if (rte->rtekind == RTE_VALUES)
4151 : : {
4152 : : /* should not find more than one VALUES RTE */
1249 dean.a.rasheed@gmail 4153 [ - + ]: 3380 : if (values_rte != NULL)
1249 dean.a.rasheed@gmail 4154 [ # # ]:UBC 0 : elog(ERROR, "more than one VALUES RTE found");
4155 : :
7216 mail@joeconway.com 4156 :CBC 3380 : values_rte = rte;
2631 dean.a.rasheed@gmail 4157 : 3380 : values_rte_index = rtr->rtindex;
4158 : : }
4159 : : }
4160 : : }
4161 : :
7216 mail@joeconway.com 4162 [ + + ]: 41559 : if (values_rte)
4163 : : {
1990 tgl@sss.pgh.pa.us 4164 : 3380 : Bitmapset *unused_values_attrnos = NULL;
4165 : :
4166 : : /* Process the main targetlist ... */
4015 andres@anarazel.de 4167 : 3380 : parsetree->targetList = rewriteTargetListIU(parsetree->targetList,
4168 : : parsetree->commandType,
4169 : : parsetree->override,
4170 : : rt_entry_relation,
4171 : : values_rte,
4172 : : values_rte_index,
4173 : : &unused_values_attrnos);
4174 : : /* ... and the VALUES expression lists */
2620 dean.a.rasheed@gmail 4175 [ + + ]: 3312 : if (!rewriteValuesRTE(parsetree, values_rte, values_rte_index,
4176 : : rt_entry_relation,
4177 : : unused_values_attrnos))
2631 4178 : 52 : defaults_remaining = true;
4179 : : }
4180 : : else
4181 : : {
4182 : : /* Process just the main targetlist */
4015 andres@anarazel.de 4183 : 38127 : parsetree->targetList =
4184 : 38179 : rewriteTargetListIU(parsetree->targetList,
4185 : : parsetree->commandType,
4186 : : parsetree->override,
4187 : : rt_entry_relation,
4188 : : NULL, 0, NULL);
4189 : : }
4190 : :
4191 [ + + ]: 41439 : if (parsetree->onConflict &&
4192 [ + + ]: 1708 : parsetree->onConflict->action == ONCONFLICT_UPDATE)
4193 : : {
4194 : 1022 : parsetree->onConflict->onConflictSet =
4195 : 1022 : rewriteTargetListIU(parsetree->onConflict->onConflictSet,
4196 : : CMD_UPDATE,
4197 : : parsetree->override,
4198 : : rt_entry_relation,
4199 : : NULL, 0, NULL);
4200 : : }
4201 : : }
5686 tgl@sss.pgh.pa.us 4202 [ + + ]: 15129 : else if (event == CMD_UPDATE)
4203 : : {
1499 alvherre@alvh.no-ip. 4204 [ - + ]: 9779 : Assert(parsetree->override == OVERRIDING_NOT_SET);
4205 : :
34 peter@eisentraut.org 4206 [ + + ]:GNC 9779 : if (parsetree->forPortionOf)
4207 : : {
4208 : : /*
4209 : : * Don't add FOR PORTION OF details until we're done rewriting
4210 : : * a view update, so that we don't add the same qual and TLE
4211 : : * on the recursion.
4212 : : *
4213 : : * Views don't need to do anything special here to remap Vars;
4214 : : * that is handled by the tree walker.
4215 : : */
4216 [ + + ]: 487 : if (rt_entry_relation->rd_rel->relkind != RELKIND_VIEW)
4217 : : {
4218 : : ListCell *tl;
4219 : :
4220 : : /*
4221 : : * Add qual: UPDATE FOR PORTION OF should be limited to
4222 : : * rows that overlap the target range.
4223 : : */
4224 : 483 : AddQual(parsetree, parsetree->forPortionOf->overlapsExpr);
4225 : :
4226 : : /* Update FOR PORTION OF column(s) automatically. */
4227 [ + - + + : 966 : foreach(tl, parsetree->forPortionOf->rangeTargetList)
+ + ]
4228 : : {
4229 : 483 : TargetEntry *tle = (TargetEntry *) lfirst(tl);
4230 : :
4231 : 483 : parsetree->targetList = lappend(parsetree->targetList, tle);
4232 : : }
4233 : : }
4234 : : }
4235 : :
4015 andres@anarazel.de 4236 :CBC 9759 : parsetree->targetList =
4237 : 9779 : rewriteTargetListIU(parsetree->targetList,
4238 : : parsetree->commandType,
4239 : : parsetree->override,
4240 : : rt_entry_relation,
4241 : : NULL, 0, NULL);
4242 : : }
1499 alvherre@alvh.no-ip. 4243 [ + + ]: 5350 : else if (event == CMD_MERGE)
4244 : : {
4245 [ - + ]: 1902 : Assert(parsetree->override == OVERRIDING_NOT_SET);
4246 : :
4247 : : /*
4248 : : * Rewrite each action targetlist separately
4249 : : */
4250 [ + - + + : 4633 : foreach(lc1, parsetree->mergeActionList)
+ + ]
4251 : : {
4252 : 2735 : MergeAction *action = (MergeAction *) lfirst(lc1);
4253 : :
4254 [ + + - ]: 2735 : switch (action->commandType)
4255 : : {
4256 : 501 : case CMD_NOTHING:
4257 : : case CMD_DELETE: /* Nothing to do here */
4258 : 501 : break;
4259 : 2234 : case CMD_UPDATE:
4260 : : case CMD_INSERT:
4261 : :
4262 : : /*
4263 : : * MERGE actions do not permit multi-row INSERTs, so
4264 : : * there is no VALUES RTE to deal with here.
4265 : : */
4266 : 2230 : action->targetList =
4267 : 2234 : rewriteTargetListIU(action->targetList,
4268 : : action->commandType,
4269 : : action->override,
4270 : : rt_entry_relation,
4271 : : NULL, 0, NULL);
4272 : 2230 : break;
1499 alvherre@alvh.no-ip. 4273 :UBC 0 : default:
4274 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d", action->commandType);
4275 : : break;
4276 : : }
4277 : : }
4278 : : }
5686 tgl@sss.pgh.pa.us 4279 [ + - ]:CBC 3448 : else if (event == CMD_DELETE)
4280 : : {
34 peter@eisentraut.org 4281 [ + + ]:GNC 3448 : if (parsetree->forPortionOf)
4282 : : {
4283 : : /*
4284 : : * Don't add FOR PORTION OF details until we're done rewriting
4285 : : * a view delete, so that we don't add the same qual on the
4286 : : * recursion.
4287 : : *
4288 : : * Views don't need to do anything special here to remap Vars;
4289 : : * that is handled by the tree walker.
4290 : : */
4291 [ + + ]: 380 : if (rt_entry_relation->rd_rel->relkind != RELKIND_VIEW)
4292 : : {
4293 : : /*
4294 : : * Add qual: DELETE FOR PORTION OF should be limited to
4295 : : * rows that overlap the target range.
4296 : : */
4297 : 376 : AddQual(parsetree, parsetree->forPortionOf->overlapsExpr);
4298 : : }
4299 : : }
4300 : : }
4301 : : else
5686 tgl@sss.pgh.pa.us 4302 [ # # ]:UBC 0 : elog(ERROR, "unrecognized commandType: %d", (int) event);
4303 : :
4304 : : /*
4305 : : * Collect and apply the appropriate rules.
4306 : : */
796 dean.a.rasheed@gmail 4307 :CBC 56544 : locks = matchLocks(event, rt_entry_relation,
4308 : : result_relation, parsetree, &hasUpdate);
4309 : :
1249 4310 : 56532 : product_orig_rt_length = list_length(parsetree->rtable);
2945 simon@2ndQuadrant.co 4311 : 56532 : product_queries = fireRules(parsetree,
4312 : : result_relation,
4313 : : event,
4314 : : locks,
4315 : : &instead,
4316 : : &returning,
4317 : : &qual_product);
4318 : :
4319 : : /*
4320 : : * If we have a VALUES RTE with any remaining untouched DEFAULT items,
4321 : : * and we got any product queries, finalize the VALUES RTE for each
4322 : : * product query (replacing the remaining DEFAULT items with NULLs).
4323 : : * We don't do this for the original query, because we know that it
4324 : : * must be an auto-insert on a view, and so should use the base
4325 : : * relation's defaults for any remaining DEFAULT items.
4326 : : */
2631 dean.a.rasheed@gmail 4327 [ + + + + ]: 56524 : if (defaults_remaining && product_queries != NIL)
4328 : : {
4329 : : ListCell *n;
4330 : :
4331 : : /*
4332 : : * Each product query has its own copy of the VALUES RTE at the
4333 : : * same index in the rangetable, so we must finalize each one.
4334 : : *
4335 : : * Note that if the product query is an INSERT ... SELECT, then
4336 : : * the VALUES RTE will be at the same index in the SELECT part of
4337 : : * the product query rather than the top-level product query
4338 : : * itself.
4339 : : */
4340 [ + - + + : 32 : foreach(n, product_queries)
+ + ]
4341 : : {
4342 : 16 : Query *pt = (Query *) lfirst(n);
4343 : : RangeTblEntry *values_rte;
4344 : :
1167 4345 [ + - ]: 16 : if (pt->commandType == CMD_INSERT &&
4346 [ + - + - : 32 : pt->jointree && IsA(pt->jointree, FromExpr) &&
+ - ]
4347 : 16 : list_length(pt->jointree->fromlist) == 1)
4348 : : {
4349 : 16 : Node *jtnode = (Node *) linitial(pt->jointree->fromlist);
4350 : :
4351 [ + - ]: 16 : if (IsA(jtnode, RangeTblRef))
4352 : : {
4353 : 16 : int rtindex = ((RangeTblRef *) jtnode)->rtindex;
4354 : 16 : RangeTblEntry *src_rte = rt_fetch(rtindex, pt->rtable);
4355 : :
4356 [ + + ]: 16 : if (src_rte->rtekind == RTE_SUBQUERY &&
4357 [ + - ]: 4 : src_rte->subquery &&
4358 [ + - ]: 4 : IsA(src_rte->subquery, Query) &&
4359 [ + - ]: 4 : src_rte->subquery->commandType == CMD_SELECT)
4360 : 4 : pt = src_rte->subquery;
4361 : : }
4362 : : }
4363 : :
4364 : 16 : values_rte = rt_fetch(values_rte_index, pt->rtable);
4365 [ - + ]: 16 : if (values_rte->rtekind != RTE_VALUES)
1167 dean.a.rasheed@gmail 4366 [ # # ]:UBC 0 : elog(ERROR, "failed to find VALUES RTE in product query");
4367 : :
1302 tgl@sss.pgh.pa.us 4368 :CBC 16 : rewriteValuesRTEToNulls(pt, values_rte);
4369 : : }
4370 : : }
4371 : :
4372 : : /*
4373 : : * If there was no unqualified INSTEAD rule, and the target relation
4374 : : * is a view without any INSTEAD OF triggers, see if the view can be
4375 : : * automatically updated. If so, we perform the necessary query
4376 : : * transformation here and add the resulting query to the
4377 : : * product_queries list, so that it gets recursively rewritten if
4378 : : * necessary. For MERGE, the view must be automatically updatable if
4379 : : * any of the merge actions lack a corresponding INSTEAD OF trigger.
4380 : : *
4381 : : * If the view cannot be automatically updated, we throw an error here
4382 : : * which is OK since the query would fail at runtime anyway. Throwing
4383 : : * the error here is preferable to the executor check since we have
4384 : : * more detailed information available about why the view isn't
4385 : : * updatable.
4386 : : */
2303 dean.a.rasheed@gmail 4387 [ + + ]: 56524 : if (!instead &&
4896 tgl@sss.pgh.pa.us 4388 [ + + ]: 56032 : rt_entry_relation->rd_rel->relkind == RELKIND_VIEW &&
796 dean.a.rasheed@gmail 4389 [ + + ]: 2672 : !view_has_instead_trigger(rt_entry_relation, event,
4390 : : parsetree->mergeActionList))
4391 : : {
4392 : : /*
4393 : : * If there were any qualified INSTEAD rules, don't allow the view
4394 : : * to be automatically updated (an unqualified INSTEAD rule or
4395 : : * INSTEAD OF trigger is required).
4396 : : */
2303 4397 [ + + ]: 2403 : if (qual_product != NULL)
796 4398 : 12 : error_view_not_updatable(rt_entry_relation,
4399 : : parsetree->commandType,
4400 : : parsetree->mergeActionList,
4401 : : gettext_noop("Views with conditional DO INSTEAD rules are not automatically updatable."));
4402 : :
4403 : : /*
4404 : : * Attempt to rewrite the query to automatically update the view.
4405 : : * This throws an error if the view can't be automatically
4406 : : * updated.
4407 : : */
4896 tgl@sss.pgh.pa.us 4408 : 2391 : parsetree = rewriteTargetView(parsetree, rt_entry_relation);
4409 : :
4410 : : /*
4411 : : * At this point product_queries contains any DO ALSO rule
4412 : : * actions. Add the rewritten query before or after those. This
4413 : : * must match the handling the original query would have gotten
4414 : : * below, if we allowed it to be included again.
4415 : : */
4416 [ + + ]: 2211 : if (parsetree->commandType == CMD_INSERT)
4417 : 796 : product_queries = lcons(parsetree, product_queries);
4418 : : else
4419 : 1415 : product_queries = lappend(product_queries, parsetree);
4420 : :
4421 : : /*
4422 : : * Set the "instead" flag, as if there had been an unqualified
4423 : : * INSTEAD, to prevent the original query from being included a
4424 : : * second time below. The transformation will have rewritten any
4425 : : * RETURNING list, so we can also set "returning" to forestall
4426 : : * throwing an error below.
4427 : : */
4428 : 2211 : instead = true;
4429 : 2211 : returning = true;
4015 andres@anarazel.de 4430 : 2211 : updatableview = true;
4431 : : }
4432 : :
4433 : : /*
4434 : : * If we got any product queries, recursively rewrite them --- but
4435 : : * first check for recursion!
4436 : : */
4724 bruce@momjian.us 4437 [ + + ]: 56332 : if (product_queries != NIL)
4438 : : {
4439 : : ListCell *n;
4440 : : rewrite_event *rev;
4441 : :
4442 [ + + + + : 3663 : foreach(n, rewrite_events)
+ + ]
4443 : : {
4444 : 644 : rev = (rewrite_event *) lfirst(n);
4445 [ - + ]: 644 : if (rev->relation == RelationGetRelid(rt_entry_relation) &&
4724 bruce@momjian.us 4446 [ # # ]:UBC 0 : rev->event == event)
4447 [ # # ]: 0 : ereport(ERROR,
4448 : : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
4449 : : errmsg("infinite recursion detected in rules for relation \"%s\"",
4450 : : RelationGetRelationName(rt_entry_relation))));
4451 : : }
4452 : :
146 michael@paquier.xyz 4453 :GNC 3019 : rev = palloc_object(rewrite_event);
4724 bruce@momjian.us 4454 :CBC 3019 : rev->relation = RelationGetRelid(rt_entry_relation);
4455 : 3019 : rev->event = event;
2484 tgl@sss.pgh.pa.us 4456 : 3019 : rewrite_events = lappend(rewrite_events, rev);
4457 : :
4724 bruce@momjian.us 4458 [ + - + + : 6102 : foreach(n, product_queries)
+ + ]
4459 : : {
4460 : 3179 : Query *pt = (Query *) lfirst(n);
4461 : : List *newstuff;
4462 : :
4463 : : /*
4464 : : * For an updatable view, pt might be the rewritten version of
4465 : : * the original query, in which case we pass on orig_rt_length
4466 : : * to finish processing any VALUES RTE it contained.
4467 : : *
4468 : : * Otherwise, we have a product query created by fireRules().
4469 : : * Any VALUES RTEs from the original query have been fully
4470 : : * processed, and must be skipped when we recurse.
4471 : : */
1249 dean.a.rasheed@gmail 4472 [ + + ]: 3179 : newstuff = RewriteQuery(pt, rewrite_events,
4473 : : pt == parsetree ?
4474 : : orig_rt_length :
4475 : : product_orig_rt_length,
4476 : : num_ctes_processed);
4724 bruce@momjian.us 4477 : 3083 : rewritten = list_concat(rewritten, newstuff);
4478 : : }
4479 : :
2484 tgl@sss.pgh.pa.us 4480 : 2923 : rewrite_events = list_delete_last(rewrite_events);
4481 : : }
4482 : :
4483 : : /*
4484 : : * If there is an INSTEAD, and the original query has a RETURNING, we
4485 : : * have to have found a RETURNING in the rule(s), else fail. (Because
4486 : : * DefineQueryRewrite only allows RETURNING in unconditional INSTEAD
4487 : : * rules, there's no need to worry whether the substituted RETURNING
4488 : : * will actually be executed --- it must be.)
4489 : : */
7185 4490 [ + + + + ]: 56236 : if ((instead || qual_product != NULL) &&
4491 [ + + ]: 2823 : parsetree->returningList &&
4492 [ + + ]: 325 : !returning)
4493 : : {
4494 [ + - - - ]: 4 : switch (event)
4495 : : {
4496 : 4 : case CMD_INSERT:
4497 [ + - ]: 4 : ereport(ERROR,
4498 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4499 : : errmsg("cannot perform INSERT RETURNING on relation \"%s\"",
4500 : : RelationGetRelationName(rt_entry_relation)),
4501 : : errhint("You need an unconditional ON INSERT DO INSTEAD rule with a RETURNING clause.")));
4502 : : break;
7185 tgl@sss.pgh.pa.us 4503 :UBC 0 : case CMD_UPDATE:
4504 [ # # ]: 0 : ereport(ERROR,
4505 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4506 : : errmsg("cannot perform UPDATE RETURNING on relation \"%s\"",
4507 : : RelationGetRelationName(rt_entry_relation)),
4508 : : errhint("You need an unconditional ON UPDATE DO INSTEAD rule with a RETURNING clause.")));
4509 : : break;
4510 : 0 : case CMD_DELETE:
4511 [ # # ]: 0 : ereport(ERROR,
4512 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4513 : : errmsg("cannot perform DELETE RETURNING on relation \"%s\"",
4514 : : RelationGetRelationName(rt_entry_relation)),
4515 : : errhint("You need an unconditional ON DELETE DO INSTEAD rule with a RETURNING clause.")));
4516 : : break;
4517 : 0 : default:
4518 [ # # ]: 0 : elog(ERROR, "unrecognized commandType: %d",
4519 : : (int) event);
4520 : : break;
4521 : : }
4522 : : }
4523 : :
4524 : : /*
4525 : : * Updatable views are supported by ON CONFLICT, so don't prevent that
4526 : : * case from proceeding
4527 : : */
4015 andres@anarazel.de 4528 [ + + + + ]:CBC 56232 : if (parsetree->onConflict &&
4529 [ - + ]: 1528 : (product_queries != NIL || hasUpdate) &&
4530 [ + + ]: 172 : !updatableview)
4000 bruce@momjian.us 4531 [ + - ]: 8 : ereport(ERROR,
4532 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4533 : : errmsg("INSERT with ON CONFLICT clause cannot be used with table that has INSERT or UPDATE rules")));
4534 : :
2661 andres@anarazel.de 4535 : 56224 : table_close(rt_entry_relation, NoLock);
4536 : : }
4537 : :
4538 : : /*
4539 : : * For INSERTs, the original query is done first; for UPDATE/DELETE, it is
4540 : : * done last. This is needed because update and delete rule actions might
4541 : : * not do anything if they are invoked after the update or delete is
4542 : : * performed. The command counter increment between the query executions
4543 : : * makes the deleted (and maybe the updated) tuples disappear so the scans
4544 : : * for them in the rule actions cannot find them.
4545 : : *
4546 : : * If we found any unqualified INSTEAD, the original query is not done at
4547 : : * all, in any form. Otherwise, we add the modified form if qualified
4548 : : * INSTEADs were found, else the unmodified form.
4549 : : */
8599 tgl@sss.pgh.pa.us 4550 [ + + ]: 290685 : if (!instead)
4551 : : {
4552 [ + + ]: 288090 : if (parsetree->commandType == CMD_INSERT)
4553 : : {
4554 [ + + ]: 40287 : if (qual_product != NULL)
4555 : 196 : rewritten = lcons(qual_product, rewritten);
4556 : : else
4557 : 40091 : rewritten = lcons(parsetree, rewritten);
4558 : : }
4559 : : else
4560 : : {
4561 [ + + ]: 247803 : if (qual_product != NULL)
4562 : 20 : rewritten = lappend(rewritten, qual_product);
4563 : : else
4564 : 247783 : rewritten = lappend(rewritten, parsetree);
4565 : : }
4566 : : }
4567 : :
4568 : : /*
4569 : : * If the original query has a CTE list, and we generated more than one
4570 : : * non-utility result query, we have to fail because we'll have copied the
4571 : : * CTE list into each result query. That would break the expectation of
4572 : : * single evaluation of CTEs. This could possibly be fixed by
4573 : : * restructuring so that a CTE list can be shared across multiple Query
4574 : : * and PlannableStatement nodes.
4575 : : */
5446 4576 [ + + ]: 290685 : if (parsetree->cteList != NIL)
4577 : : {
5444 bruce@momjian.us 4578 : 1661 : int qcount = 0;
4579 : :
5446 tgl@sss.pgh.pa.us 4580 [ + - + + : 3322 : foreach(lc1, rewritten)
+ + ]
4581 : : {
4582 : 1661 : Query *q = (Query *) lfirst(lc1);
4583 : :
4584 [ + - ]: 1661 : if (q->commandType != CMD_UTILITY)
4585 : 1661 : qcount++;
4586 : : }
4587 [ - + ]: 1661 : if (qcount > 1)
5446 tgl@sss.pgh.pa.us 4588 [ # # ]:UBC 0 : ereport(ERROR,
4589 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4590 : : errmsg("WITH cannot be used in a query that is rewritten by rules into multiple queries")));
4591 : : }
4592 : :
10467 bruce@momjian.us 4593 :CBC 290685 : return rewritten;
4594 : : }
4595 : :
4596 : :
4597 : : /*
4598 : : * Get a table's generated columns
4599 : : *
4600 : : * If include_stored is true, both stored and virtual generated columns are
4601 : : * returned. Otherwise, only virtual generated columns are returned.
4602 : : *
4603 : : * Returns a list of TargetEntry, one for each generated column, containing
4604 : : * the attribute numbers and generation expressions.
4605 : : */
4606 : : static List *
14 rguo@postgresql.org 4607 : 1501 : get_generated_columns(Relation rel, int rt_index, bool include_stored)
4608 : : {
4609 : 1501 : List *gen_cols = NIL;
4610 : : TupleDesc tupdesc;
4611 : :
452 peter@eisentraut.org 4612 : 1501 : tupdesc = RelationGetDescr(rel);
14 rguo@postgresql.org 4613 [ + + ]: 1501 : if (tupdesc->constr &&
4614 [ + + + - ]: 633 : (tupdesc->constr->has_generated_virtual ||
4615 [ + + ]: 256 : (include_stored && tupdesc->constr->has_generated_stored)))
4616 : : {
452 peter@eisentraut.org 4617 [ + + ]: 1492 : for (int i = 0; i < tupdesc->natts; i++)
4618 : : {
4619 : 1099 : Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
4620 : :
14 rguo@postgresql.org 4621 [ + + + + ]: 1099 : if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL ||
4622 [ + + ]: 48 : (include_stored && attr->attgenerated == ATTRIBUTE_GENERATED_STORED))
4623 : : {
4624 : : Node *defexpr;
4625 : : TargetEntry *te;
4626 : :
434 4627 : 513 : defexpr = build_generation_expression(rel, i + 1);
452 peter@eisentraut.org 4628 : 513 : ChangeVarNodes(defexpr, 1, rt_index, 0);
4629 : :
434 rguo@postgresql.org 4630 : 513 : te = makeTargetEntry((Expr *) defexpr, i + 1, 0, false);
14 4631 : 513 : gen_cols = lappend(gen_cols, te);
4632 : : }
4633 : : }
4634 : : }
4635 : :
4636 : 1501 : return gen_cols;
4637 : : }
4638 : :
4639 : : /*
4640 : : * Expand virtual generated columns in an expression
4641 : : *
4642 : : * This is for expressions that are not part of a query, such as default
4643 : : * expressions or index predicates. The rt_index is usually 1.
4644 : : */
4645 : : Node *
452 peter@eisentraut.org 4646 : 10854 : expand_generated_columns_in_expr(Node *node, Relation rel, int rt_index)
4647 : : {
4648 : 10854 : TupleDesc tupdesc = RelationGetDescr(rel);
4649 : :
4650 [ + + + + ]: 10854 : if (tupdesc->constr && tupdesc->constr->has_generated_virtual)
4651 : : {
4652 : : RangeTblEntry *rte;
4653 : : List *vcols;
4654 : :
4655 : 361 : rte = makeNode(RangeTblEntry);
4656 : : /* eref needs to be set, but the actual name doesn't matter */
4657 : 361 : rte->eref = makeAlias(RelationGetRelationName(rel), NIL);
4658 : 361 : rte->rtekind = RTE_RELATION;
4659 : 361 : rte->relid = RelationGetRelid(rel);
4660 : :
14 rguo@postgresql.org 4661 : 361 : vcols = get_generated_columns(rel, rt_index, false);
4662 : :
4663 [ + - ]: 361 : if (vcols)
4664 : : {
4665 : : /*
4666 : : * Passing NULL for outer_hasSubLinks is safe because generation
4667 : : * expressions cannot contain SubLinks, so the replacement cannot
4668 : : * introduce any.
4669 : : */
4670 : 361 : node = ReplaceVarsFromTargetList(node, rt_index, 0, rte, vcols, 0,
4671 : : REPLACEVARS_CHANGE_VARNO, rt_index,
4672 : : NULL);
4673 : : }
4674 : : }
4675 : :
452 peter@eisentraut.org 4676 : 10854 : return node;
4677 : : }
4678 : :
4679 : : /*
4680 : : * Build the generation expression for a generated column.
4681 : : *
4682 : : * Error out if there is no generation expression found for the given column.
4683 : : */
4684 : : Node *
434 rguo@postgresql.org 4685 : 2096 : build_generation_expression(Relation rel, int attrno)
4686 : : {
4687 : 2096 : TupleDesc rd_att = RelationGetDescr(rel);
4688 : 2096 : Form_pg_attribute att_tup = TupleDescAttr(rd_att, attrno - 1);
4689 : : Node *defexpr;
4690 : : Oid attcollid;
4691 : :
14 4692 [ + - + + : 2096 : Assert(rd_att->constr &&
- + ]
4693 : : (rd_att->constr->has_generated_virtual ||
4694 : : rd_att->constr->has_generated_stored));
4695 [ + + - + ]: 2096 : Assert(att_tup->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL ||
4696 : : att_tup->attgenerated == ATTRIBUTE_GENERATED_STORED);
4697 : :
434 4698 : 2096 : defexpr = build_column_default(rel, attrno);
4699 [ - + ]: 2096 : if (defexpr == NULL)
434 rguo@postgresql.org 4700 [ # # ]:UBC 0 : elog(ERROR, "no generation expression found for column number %d of table \"%s\"",
4701 : : attrno, RelationGetRelationName(rel));
4702 : :
4703 : : /*
4704 : : * If the column definition has a collation and it is different from the
4705 : : * collation of the generation expression, put a COLLATE clause around the
4706 : : * expression.
4707 : : */
434 rguo@postgresql.org 4708 :CBC 2096 : attcollid = att_tup->attcollation;
4709 [ + + + + ]: 2096 : if (attcollid && attcollid != exprCollation(defexpr))
4710 : : {
4711 : 10 : CollateExpr *ce = makeNode(CollateExpr);
4712 : :
4713 : 10 : ce->arg = (Expr *) defexpr;
4714 : 10 : ce->collOid = attcollid;
4715 : 10 : ce->location = -1;
4716 : :
4717 : 10 : defexpr = (Node *) ce;
4718 : : }
4719 : :
4720 : 2096 : return defexpr;
4721 : : }
4722 : :
4723 : :
4724 : : /*
4725 : : * QueryRewrite -
4726 : : * Primary entry point to the query rewriter.
4727 : : * Rewrite one query via query rewrite system, possibly returning 0
4728 : : * or many queries.
4729 : : *
4730 : : * NOTE: the parsetree must either have come straight from the parser,
4731 : : * or have been scanned by AcquireRewriteLocks to acquire suitable locks.
4732 : : */
4733 : : List *
9343 tgl@sss.pgh.pa.us 4734 : 287740 : QueryRewrite(Query *parsetree)
4735 : : {
340 drowley@postgresql.o 4736 : 287740 : int64 input_query_id = parsetree->queryId;
4737 : : List *querylist;
4738 : : List *results;
4739 : : ListCell *l;
4740 : : CmdType origCmdType;
4741 : : bool foundOriginalQuery;
4742 : : Query *lastInstead;
4743 : :
4744 : : /*
4745 : : * This function is only applied to top-level original queries
4746 : : */
5548 tgl@sss.pgh.pa.us 4747 [ - + ]: 287740 : Assert(parsetree->querySource == QSRC_ORIGINAL);
4748 [ - + ]: 287740 : Assert(parsetree->canSetTag);
4749 : :
4750 : : /*
4751 : : * Step 1
4752 : : *
4753 : : * Apply all non-SELECT rules possibly getting 0 or many queries
4754 : : */
157 dean.a.rasheed@gmail 4755 : 287740 : querylist = RewriteQuery(parsetree, NIL, 0, 0);
4756 : :
4757 : : /*
4758 : : * Step 2
4759 : : *
4760 : : * Apply all the RIR rules on each query
4761 : : *
4762 : : * This is also a handy place to mark each query with the original queryId
4763 : : */
5686 tgl@sss.pgh.pa.us 4764 : 287352 : results = NIL;
9842 bruce@momjian.us 4765 [ + + + + : 575036 : foreach(l, querylist)
+ + ]
4766 : : {
9175 4767 : 287820 : Query *query = (Query *) lfirst(l);
4768 : :
2943 tgl@sss.pgh.pa.us 4769 : 287820 : query = fireRIRrules(query, NIL);
4770 : :
5152 4771 : 287684 : query->queryId = input_query_id;
4772 : :
9343 4773 : 287684 : results = lappend(results, query);
4774 : : }
4775 : :
4776 : : /*
4777 : : * Step 3
4778 : : *
4779 : : * Determine which, if any, of the resulting queries is supposed to set
4780 : : * the command-result tag; and update the canSetTag fields accordingly.
4781 : : *
4782 : : * If the original query is still in the list, it sets the command tag.
4783 : : * Otherwise, the last INSTEAD query of the same kind as the original is
4784 : : * allowed to set the tag. (Note these rules can leave us with no query
4785 : : * setting the tag. The tcop code has to cope with this by setting up a
4786 : : * default tag based on the original un-rewritten query.)
4787 : : *
4788 : : * The Asserts verify that at most one query in the result list is marked
4789 : : * canSetTag. If we aren't checking asserts, we can fall out of the loop
4790 : : * as soon as we find the original query.
4791 : : */
8404 4792 : 287216 : origCmdType = parsetree->commandType;
4793 : 287216 : foundOriginalQuery = false;
4794 : 287216 : lastInstead = NULL;
4795 : :
4796 [ + + + + : 574900 : foreach(l, results)
+ + ]
4797 : : {
4798 : 287684 : Query *query = (Query *) lfirst(l);
4799 : :
4800 [ + + ]: 287684 : if (query->querySource == QSRC_ORIGINAL)
4801 : : {
4802 [ - + ]: 286756 : Assert(query->canSetTag);
4803 [ - + ]: 286756 : Assert(!foundOriginalQuery);
4804 : 286756 : foundOriginalQuery = true;
4805 : : #ifndef USE_ASSERT_CHECKING
4806 : : break;
4807 : : #endif
4808 : : }
4809 : : else
4810 : : {
4811 [ - + ]: 928 : Assert(!query->canSetTag);
4812 [ + + ]: 928 : if (query->commandType == origCmdType &&
4813 [ + + ]: 720 : (query->querySource == QSRC_INSTEAD_RULE ||
4814 [ + + ]: 360 : query->querySource == QSRC_QUAL_INSTEAD_RULE))
4815 : 512 : lastInstead = query;
4816 : : }
4817 : : }
4818 : :
4819 [ + + + + ]: 287216 : if (!foundOriginalQuery && lastInstead != NULL)
4820 : 376 : lastInstead->canSetTag = true;
4821 : :
9343 4822 : 287216 : return results;
4823 : : }
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