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parse_relation.c
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1 /*-------------------------------------------------------------------------
2  *
3  * parse_relation.c
4  * parser support routines dealing with relations
5  *
6  * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/backend/parser/parse_relation.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 #include "postgres.h"
16 
17 #include <ctype.h>
18 
19 #include "access/htup_details.h"
20 #include "access/relation.h"
21 #include "access/sysattr.h"
22 #include "access/table.h"
23 #include "catalog/heap.h"
24 #include "catalog/namespace.h"
25 #include "catalog/pg_type.h"
26 #include "funcapi.h"
27 #include "nodes/makefuncs.h"
28 #include "nodes/nodeFuncs.h"
29 #include "parser/parse_enr.h"
30 #include "parser/parse_relation.h"
31 #include "parser/parse_type.h"
32 #include "parser/parsetree.h"
33 #include "storage/lmgr.h"
34 #include "utils/builtins.h"
35 #include "utils/lsyscache.h"
36 #include "utils/rel.h"
37 #include "utils/syscache.h"
38 #include "utils/varlena.h"
39 
40 
41 /*
42  * Support for fuzzily matching columns.
43  *
44  * This is for building diagnostic messages, where non-exact matching
45  * attributes are suggested to the user. The struct's fields may be facets of
46  * a particular RTE, or of an entire range table, depending on context.
47  */
48 typedef struct
49 {
50  int distance; /* Weighted distance (lowest so far) */
51  RangeTblEntry *rfirst; /* RTE of first */
52  AttrNumber first; /* Closest attribute so far */
53  RangeTblEntry *rsecond; /* RTE of second */
54  AttrNumber second; /* Second closest attribute so far */
56 
57 #define MAX_FUZZY_DISTANCE 3
58 
59 
61  const char *refname,
62  int location);
64  int location);
65 static void check_lateral_ref_ok(ParseState *pstate, ParseNamespaceItem *nsitem,
66  int location);
67 static int scanRTEForColumn(ParseState *pstate, RangeTblEntry *rte,
68  Alias *eref,
69  const char *colname, int location,
70  int fuzzy_rte_penalty,
71  FuzzyAttrMatchState *fuzzystate);
72 static void markRTEForSelectPriv(ParseState *pstate,
73  int rtindex, AttrNumber col);
74 static void expandRelation(Oid relid, Alias *eref,
75  int rtindex, int sublevels_up,
76  int location, bool include_dropped,
77  List **colnames, List **colvars);
78 static void expandTupleDesc(TupleDesc tupdesc, Alias *eref,
79  int count, int offset,
80  int rtindex, int sublevels_up,
81  int location, bool include_dropped,
82  List **colnames, List **colvars);
83 static int specialAttNum(const char *attname);
84 static bool isQueryUsingTempRelation_walker(Node *node, void *context);
85 
86 
87 /*
88  * refnameNamespaceItem
89  * Given a possibly-qualified refname, look to see if it matches any visible
90  * namespace item. If so, return a pointer to the nsitem; else return NULL.
91  *
92  * Optionally get nsitem's nesting depth (0 = current) into *sublevels_up.
93  * If sublevels_up is NULL, only consider items at the current nesting
94  * level.
95  *
96  * An unqualified refname (schemaname == NULL) can match any item with matching
97  * alias, or matching unqualified relname in the case of alias-less relation
98  * items. It is possible that such a refname matches multiple items in the
99  * nearest nesting level that has a match; if so, we report an error via
100  * ereport().
101  *
102  * A qualified refname (schemaname != NULL) can only match a relation item
103  * that (a) has no alias and (b) is for the same relation identified by
104  * schemaname.refname. In this case we convert schemaname.refname to a
105  * relation OID and search by relid, rather than by alias name. This is
106  * peculiar, but it's what SQL says to do.
107  */
110  const char *schemaname,
111  const char *refname,
112  int location,
113  int *sublevels_up)
114 {
115  Oid relId = InvalidOid;
116 
117  if (sublevels_up)
118  *sublevels_up = 0;
119 
120  if (schemaname != NULL)
121  {
122  Oid namespaceId;
123 
124  /*
125  * We can use LookupNamespaceNoError() here because we are only
126  * interested in finding existing RTEs. Checking USAGE permission on
127  * the schema is unnecessary since it would have already been checked
128  * when the RTE was made. Furthermore, we want to report "RTE not
129  * found", not "no permissions for schema", if the name happens to
130  * match a schema name the user hasn't got access to.
131  */
132  namespaceId = LookupNamespaceNoError(schemaname);
133  if (!OidIsValid(namespaceId))
134  return NULL;
135  relId = get_relname_relid(refname, namespaceId);
136  if (!OidIsValid(relId))
137  return NULL;
138  }
139 
140  while (pstate != NULL)
141  {
142  ParseNamespaceItem *result;
143 
144  if (OidIsValid(relId))
145  result = scanNameSpaceForRelid(pstate, relId, location);
146  else
147  result = scanNameSpaceForRefname(pstate, refname, location);
148 
149  if (result)
150  return result;
151 
152  if (sublevels_up)
153  (*sublevels_up)++;
154  else
155  break;
156 
157  pstate = pstate->parentParseState;
158  }
159  return NULL;
160 }
161 
162 /*
163  * Search the query's table namespace for an item matching the
164  * given unqualified refname. Return the nsitem if a unique match, or NULL
165  * if no match. Raise error if multiple matches.
166  *
167  * Note: it might seem that we shouldn't have to worry about the possibility
168  * of multiple matches; after all, the SQL standard disallows duplicate table
169  * aliases within a given SELECT level. Historically, however, Postgres has
170  * been laxer than that. For example, we allow
171  * SELECT ... FROM tab1 x CROSS JOIN (tab2 x CROSS JOIN tab3 y) z
172  * on the grounds that the aliased join (z) hides the aliases within it,
173  * therefore there is no conflict between the two RTEs named "x". However,
174  * if tab3 is a LATERAL subquery, then from within the subquery both "x"es
175  * are visible. Rather than rejecting queries that used to work, we allow
176  * this situation, and complain only if there's actually an ambiguous
177  * reference to "x".
178  */
179 static ParseNamespaceItem *
180 scanNameSpaceForRefname(ParseState *pstate, const char *refname, int location)
181 {
182  ParseNamespaceItem *result = NULL;
183  ListCell *l;
184 
185  foreach(l, pstate->p_namespace)
186  {
188 
189  /* Ignore columns-only items */
190  if (!nsitem->p_rel_visible)
191  continue;
192  /* If not inside LATERAL, ignore lateral-only items */
193  if (nsitem->p_lateral_only && !pstate->p_lateral_active)
194  continue;
195 
196  if (strcmp(nsitem->p_names->aliasname, refname) == 0)
197  {
198  if (result)
199  ereport(ERROR,
200  (errcode(ERRCODE_AMBIGUOUS_ALIAS),
201  errmsg("table reference \"%s\" is ambiguous",
202  refname),
203  parser_errposition(pstate, location)));
204  check_lateral_ref_ok(pstate, nsitem, location);
205  result = nsitem;
206  }
207  }
208  return result;
209 }
210 
211 /*
212  * Search the query's table namespace for a relation item matching the
213  * given relation OID. Return the nsitem if a unique match, or NULL
214  * if no match. Raise error if multiple matches.
215  *
216  * See the comments for refnameNamespaceItem to understand why this
217  * acts the way it does.
218  */
219 static ParseNamespaceItem *
220 scanNameSpaceForRelid(ParseState *pstate, Oid relid, int location)
221 {
222  ParseNamespaceItem *result = NULL;
223  ListCell *l;
224 
225  foreach(l, pstate->p_namespace)
226  {
228  RangeTblEntry *rte = nsitem->p_rte;
229 
230  /* Ignore columns-only items */
231  if (!nsitem->p_rel_visible)
232  continue;
233  /* If not inside LATERAL, ignore lateral-only items */
234  if (nsitem->p_lateral_only && !pstate->p_lateral_active)
235  continue;
236 
237  /* yes, the test for alias == NULL should be there... */
238  if (rte->rtekind == RTE_RELATION &&
239  rte->relid == relid &&
240  rte->alias == NULL)
241  {
242  if (result)
243  ereport(ERROR,
244  (errcode(ERRCODE_AMBIGUOUS_ALIAS),
245  errmsg("table reference %u is ambiguous",
246  relid),
247  parser_errposition(pstate, location)));
248  check_lateral_ref_ok(pstate, nsitem, location);
249  result = nsitem;
250  }
251  }
252  return result;
253 }
254 
255 /*
256  * Search the query's CTE namespace for a CTE matching the given unqualified
257  * refname. Return the CTE (and its levelsup count) if a match, or NULL
258  * if no match. We need not worry about multiple matches, since parse_cte.c
259  * rejects WITH lists containing duplicate CTE names.
260  */
262 scanNameSpaceForCTE(ParseState *pstate, const char *refname,
263  Index *ctelevelsup)
264 {
265  Index levelsup;
266 
267  for (levelsup = 0;
268  pstate != NULL;
269  pstate = pstate->parentParseState, levelsup++)
270  {
271  ListCell *lc;
272 
273  foreach(lc, pstate->p_ctenamespace)
274  {
275  CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
276 
277  if (strcmp(cte->ctename, refname) == 0)
278  {
279  *ctelevelsup = levelsup;
280  return cte;
281  }
282  }
283  }
284  return NULL;
285 }
286 
287 /*
288  * Search for a possible "future CTE", that is one that is not yet in scope
289  * according to the WITH scoping rules. This has nothing to do with valid
290  * SQL semantics, but it's important for error reporting purposes.
291  */
292 static bool
293 isFutureCTE(ParseState *pstate, const char *refname)
294 {
295  for (; pstate != NULL; pstate = pstate->parentParseState)
296  {
297  ListCell *lc;
298 
299  foreach(lc, pstate->p_future_ctes)
300  {
301  CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
302 
303  if (strcmp(cte->ctename, refname) == 0)
304  return true;
305  }
306  }
307  return false;
308 }
309 
310 /*
311  * Search the query's ephemeral named relation namespace for a relation
312  * matching the given unqualified refname.
313  */
314 bool
315 scanNameSpaceForENR(ParseState *pstate, const char *refname)
316 {
317  return name_matches_visible_ENR(pstate, refname);
318 }
319 
320 /*
321  * searchRangeTableForRel
322  * See if any RangeTblEntry could possibly match the RangeVar.
323  * If so, return a pointer to the RangeTblEntry; else return NULL.
324  *
325  * This is different from refnameNamespaceItem in that it considers every
326  * entry in the ParseState's rangetable(s), not only those that are currently
327  * visible in the p_namespace list(s). This behavior is invalid per the SQL
328  * spec, and it may give ambiguous results (there might be multiple equally
329  * valid matches, but only one will be returned). This must be used ONLY
330  * as a heuristic in giving suitable error messages. See errorMissingRTE.
331  *
332  * Notice that we consider both matches on actual relation (or CTE) name
333  * and matches on alias.
334  */
335 static RangeTblEntry *
337 {
338  const char *refname = relation->relname;
339  Oid relId = InvalidOid;
340  CommonTableExpr *cte = NULL;
341  bool isenr = false;
342  Index ctelevelsup = 0;
343  Index levelsup;
344 
345  /*
346  * If it's an unqualified name, check for possible CTE matches. A CTE
347  * hides any real relation matches. If no CTE, look for a matching
348  * relation.
349  *
350  * NB: It's not critical that RangeVarGetRelid return the correct answer
351  * here in the face of concurrent DDL. If it doesn't, the worst case
352  * scenario is a less-clear error message. Also, the tables involved in
353  * the query are already locked, which reduces the number of cases in
354  * which surprising behavior can occur. So we do the name lookup
355  * unlocked.
356  */
357  if (!relation->schemaname)
358  {
359  cte = scanNameSpaceForCTE(pstate, refname, &ctelevelsup);
360  if (!cte)
361  isenr = scanNameSpaceForENR(pstate, refname);
362  }
363 
364  if (!cte && !isenr)
365  relId = RangeVarGetRelid(relation, NoLock, true);
366 
367  /* Now look for RTEs matching either the relation/CTE/ENR or the alias */
368  for (levelsup = 0;
369  pstate != NULL;
370  pstate = pstate->parentParseState, levelsup++)
371  {
372  ListCell *l;
373 
374  foreach(l, pstate->p_rtable)
375  {
376  RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
377 
378  if (rte->rtekind == RTE_RELATION &&
379  OidIsValid(relId) &&
380  rte->relid == relId)
381  return rte;
382  if (rte->rtekind == RTE_CTE &&
383  cte != NULL &&
384  rte->ctelevelsup + levelsup == ctelevelsup &&
385  strcmp(rte->ctename, refname) == 0)
386  return rte;
387  if (rte->rtekind == RTE_NAMEDTUPLESTORE &&
388  isenr &&
389  strcmp(rte->enrname, refname) == 0)
390  return rte;
391  if (strcmp(rte->eref->aliasname, refname) == 0)
392  return rte;
393  }
394  }
395  return NULL;
396 }
397 
398 /*
399  * Check for relation-name conflicts between two namespace lists.
400  * Raise an error if any is found.
401  *
402  * Note: we assume that each given argument does not contain conflicts
403  * itself; we just want to know if the two can be merged together.
404  *
405  * Per SQL, two alias-less plain relation RTEs do not conflict even if
406  * they have the same eref->aliasname (ie, same relation name), if they
407  * are for different relation OIDs (implying they are in different schemas).
408  *
409  * We ignore the lateral-only flags in the namespace items: the lists must
410  * not conflict, even when all items are considered visible. However,
411  * columns-only items should be ignored.
412  */
413 void
415  List *namespace2)
416 {
417  ListCell *l1;
418 
419  foreach(l1, namespace1)
420  {
421  ParseNamespaceItem *nsitem1 = (ParseNamespaceItem *) lfirst(l1);
422  RangeTblEntry *rte1 = nsitem1->p_rte;
423  const char *aliasname1 = nsitem1->p_names->aliasname;
424  ListCell *l2;
425 
426  if (!nsitem1->p_rel_visible)
427  continue;
428 
429  foreach(l2, namespace2)
430  {
431  ParseNamespaceItem *nsitem2 = (ParseNamespaceItem *) lfirst(l2);
432  RangeTblEntry *rte2 = nsitem2->p_rte;
433  const char *aliasname2 = nsitem2->p_names->aliasname;
434 
435  if (!nsitem2->p_rel_visible)
436  continue;
437  if (strcmp(aliasname2, aliasname1) != 0)
438  continue; /* definitely no conflict */
439  if (rte1->rtekind == RTE_RELATION && rte1->alias == NULL &&
440  rte2->rtekind == RTE_RELATION && rte2->alias == NULL &&
441  rte1->relid != rte2->relid)
442  continue; /* no conflict per SQL rule */
443  ereport(ERROR,
444  (errcode(ERRCODE_DUPLICATE_ALIAS),
445  errmsg("table name \"%s\" specified more than once",
446  aliasname1)));
447  }
448  }
449 }
450 
451 /*
452  * Complain if a namespace item is currently disallowed as a LATERAL reference.
453  * This enforces both SQL:2008's rather odd idea of what to do with a LATERAL
454  * reference to the wrong side of an outer join, and our own prohibition on
455  * referencing the target table of an UPDATE or DELETE as a lateral reference
456  * in a FROM/USING clause.
457  *
458  * Note: the pstate should be the same query level the nsitem was found in.
459  *
460  * Convenience subroutine to avoid multiple copies of a rather ugly ereport.
461  */
462 static void
464  int location)
465 {
466  if (nsitem->p_lateral_only && !nsitem->p_lateral_ok)
467  {
468  /* SQL:2008 demands this be an error, not an invisible item */
469  RangeTblEntry *rte = nsitem->p_rte;
470  char *refname = nsitem->p_names->aliasname;
471 
472  ereport(ERROR,
473  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
474  errmsg("invalid reference to FROM-clause entry for table \"%s\"",
475  refname),
476  (pstate->p_target_nsitem != NULL &&
477  rte == pstate->p_target_nsitem->p_rte) ?
478  errhint("There is an entry for table \"%s\", but it cannot be referenced from this part of the query.",
479  refname) :
480  errdetail("The combining JOIN type must be INNER or LEFT for a LATERAL reference."),
481  parser_errposition(pstate, location)));
482  }
483 }
484 
485 /*
486  * Given an RT index and nesting depth, find the corresponding
487  * ParseNamespaceItem (there must be one).
488  */
491  int varno,
492  int sublevels_up)
493 {
494  ListCell *lc;
495 
496  while (sublevels_up-- > 0)
497  {
498  pstate = pstate->parentParseState;
499  Assert(pstate != NULL);
500  }
501  foreach(lc, pstate->p_namespace)
502  {
503  ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(lc);
504 
505  if (nsitem->p_rtindex == varno)
506  return nsitem;
507  }
508  elog(ERROR, "nsitem not found (internal error)");
509  return NULL; /* keep compiler quiet */
510 }
511 
512 /*
513  * Given an RT index and nesting depth, find the corresponding RTE.
514  * (Note that the RTE need not be in the query's namespace.)
515  */
518  int varno,
519  int sublevels_up)
520 {
521  while (sublevels_up-- > 0)
522  {
523  pstate = pstate->parentParseState;
524  Assert(pstate != NULL);
525  }
526  Assert(varno > 0 && varno <= list_length(pstate->p_rtable));
527  return rt_fetch(varno, pstate->p_rtable);
528 }
529 
530 /*
531  * Fetch the CTE for a CTE-reference RTE.
532  *
533  * rtelevelsup is the number of query levels above the given pstate that the
534  * RTE came from.
535  */
537 GetCTEForRTE(ParseState *pstate, RangeTblEntry *rte, int rtelevelsup)
538 {
539  Index levelsup;
540  ListCell *lc;
541 
542  Assert(rte->rtekind == RTE_CTE);
543  levelsup = rte->ctelevelsup + rtelevelsup;
544  while (levelsup-- > 0)
545  {
546  pstate = pstate->parentParseState;
547  if (!pstate) /* shouldn't happen */
548  elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
549  }
550  foreach(lc, pstate->p_ctenamespace)
551  {
552  CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
553 
554  if (strcmp(cte->ctename, rte->ctename) == 0)
555  return cte;
556  }
557  /* shouldn't happen */
558  elog(ERROR, "could not find CTE \"%s\"", rte->ctename);
559  return NULL; /* keep compiler quiet */
560 }
561 
562 /*
563  * updateFuzzyAttrMatchState
564  * Using Levenshtein distance, consider if column is best fuzzy match.
565  */
566 static void
567 updateFuzzyAttrMatchState(int fuzzy_rte_penalty,
568  FuzzyAttrMatchState *fuzzystate, RangeTblEntry *rte,
569  const char *actual, const char *match, int attnum)
570 {
571  int columndistance;
572  int matchlen;
573 
574  /* Bail before computing the Levenshtein distance if there's no hope. */
575  if (fuzzy_rte_penalty > fuzzystate->distance)
576  return;
577 
578  /*
579  * Outright reject dropped columns, which can appear here with apparent
580  * empty actual names, per remarks within scanRTEForColumn().
581  */
582  if (actual[0] == '\0')
583  return;
584 
585  /* Use Levenshtein to compute match distance. */
586  matchlen = strlen(match);
587  columndistance =
588  varstr_levenshtein_less_equal(actual, strlen(actual), match, matchlen,
589  1, 1, 1,
590  fuzzystate->distance + 1
591  - fuzzy_rte_penalty,
592  true);
593 
594  /*
595  * If more than half the characters are different, don't treat it as a
596  * match, to avoid making ridiculous suggestions.
597  */
598  if (columndistance > matchlen / 2)
599  return;
600 
601  /*
602  * From this point on, we can ignore the distinction between the RTE-name
603  * distance and the column-name distance.
604  */
605  columndistance += fuzzy_rte_penalty;
606 
607  /*
608  * If the new distance is less than or equal to that of the best match
609  * found so far, update fuzzystate.
610  */
611  if (columndistance < fuzzystate->distance)
612  {
613  /* Store new lowest observed distance for RTE */
614  fuzzystate->distance = columndistance;
615  fuzzystate->rfirst = rte;
616  fuzzystate->first = attnum;
617  fuzzystate->rsecond = NULL;
618  fuzzystate->second = InvalidAttrNumber;
619  }
620  else if (columndistance == fuzzystate->distance)
621  {
622  /*
623  * This match distance may equal a prior match within this same range
624  * table. When that happens, the prior match may also be given, but
625  * only if there is no more than two equally distant matches from the
626  * RTE (in turn, our caller will only accept two equally distant
627  * matches overall).
628  */
629  if (AttributeNumberIsValid(fuzzystate->second))
630  {
631  /* Too many RTE-level matches */
632  fuzzystate->rfirst = NULL;
633  fuzzystate->first = InvalidAttrNumber;
634  fuzzystate->rsecond = NULL;
635  fuzzystate->second = InvalidAttrNumber;
636  /* Clearly, distance is too low a bar (for *any* RTE) */
637  fuzzystate->distance = columndistance - 1;
638  }
639  else if (AttributeNumberIsValid(fuzzystate->first))
640  {
641  /* Record as provisional second match for RTE */
642  fuzzystate->rsecond = rte;
643  fuzzystate->second = attnum;
644  }
645  else if (fuzzystate->distance <= MAX_FUZZY_DISTANCE)
646  {
647  /*
648  * Record as provisional first match (this can occasionally occur
649  * because previous lowest distance was "too low a bar", rather
650  * than being associated with a real match)
651  */
652  fuzzystate->rfirst = rte;
653  fuzzystate->first = attnum;
654  }
655  }
656 }
657 
658 /*
659  * scanNSItemForColumn
660  * Search the column names of a single namespace item for the given name.
661  * If found, return an appropriate Var node, else return NULL.
662  * If the name proves ambiguous within this nsitem, raise error.
663  *
664  * Side effect: if we find a match, mark the corresponding RTE as requiring
665  * read access for the column.
666  */
667 Node *
669  int sublevels_up, const char *colname, int location)
670 {
671  RangeTblEntry *rte = nsitem->p_rte;
672  int attnum;
673  Var *var;
674 
675  /*
676  * Scan the nsitem's column names (or aliases) for a match. Complain if
677  * multiple matches.
678  */
679  attnum = scanRTEForColumn(pstate, rte, nsitem->p_names,
680  colname, location,
681  0, NULL);
682 
683  if (attnum == InvalidAttrNumber)
684  return NULL; /* Return NULL if no match */
685 
686  /* In constraint check, no system column is allowed except tableOid */
687  if (pstate->p_expr_kind == EXPR_KIND_CHECK_CONSTRAINT &&
688  attnum < InvalidAttrNumber && attnum != TableOidAttributeNumber)
689  ereport(ERROR,
690  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
691  errmsg("system column \"%s\" reference in check constraint is invalid",
692  colname),
693  parser_errposition(pstate, location)));
694 
695  /* In generated column, no system column is allowed except tableOid */
696  if (pstate->p_expr_kind == EXPR_KIND_GENERATED_COLUMN &&
697  attnum < InvalidAttrNumber && attnum != TableOidAttributeNumber)
698  ereport(ERROR,
699  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
700  errmsg("cannot use system column \"%s\" in column generation expression",
701  colname),
702  parser_errposition(pstate, location)));
703 
704  /* Found a valid match, so build a Var */
705  if (attnum > InvalidAttrNumber)
706  {
707  /* Get attribute data from the ParseNamespaceColumn array */
708  ParseNamespaceColumn *nscol = &nsitem->p_nscolumns[attnum - 1];
709 
710  /* Complain if dropped column. See notes in scanRTEForColumn. */
711  if (nscol->p_varno == 0)
712  ereport(ERROR,
713  (errcode(ERRCODE_UNDEFINED_COLUMN),
714  errmsg("column \"%s\" of relation \"%s\" does not exist",
715  colname,
716  nsitem->p_names->aliasname)));
717 
718  var = makeVar(nscol->p_varno,
719  nscol->p_varattno,
720  nscol->p_vartype,
721  nscol->p_vartypmod,
722  nscol->p_varcollid,
723  sublevels_up);
724  /* makeVar doesn't offer parameters for these, so set them by hand: */
725  var->varnosyn = nscol->p_varnosyn;
726  var->varattnosyn = nscol->p_varattnosyn;
727  }
728  else
729  {
730  /* System column, so use predetermined type data */
731  const FormData_pg_attribute *sysatt;
732 
733  sysatt = SystemAttributeDefinition(attnum);
734  var = makeVar(nsitem->p_rtindex,
735  attnum,
736  sysatt->atttypid,
737  sysatt->atttypmod,
738  sysatt->attcollation,
739  sublevels_up);
740  }
741  var->location = location;
742 
743  /* Require read access to the column */
744  markVarForSelectPriv(pstate, var);
745 
746  return (Node *) var;
747 }
748 
749 /*
750  * scanRTEForColumn
751  * Search the column names of a single RTE for the given name.
752  * If found, return the attnum (possibly negative, for a system column);
753  * else return InvalidAttrNumber.
754  * If the name proves ambiguous within this RTE, raise error.
755  *
756  * Actually, we only search the names listed in "eref". This can be either
757  * rte->eref, in which case we are indeed searching all the column names,
758  * or for a join it can be rte->join_using_alias, in which case we are only
759  * considering the common column names (which are the first N columns of the
760  * join, so everything works).
761  *
762  * pstate and location are passed only for error-reporting purposes.
763  *
764  * Side effect: if fuzzystate is non-NULL, check non-system columns
765  * for an approximate match and update fuzzystate accordingly.
766  *
767  * Note: this is factored out of scanNSItemForColumn because error message
768  * creation may want to check RTEs that are not in the namespace. To support
769  * that usage, minimize the number of validity checks performed here. It's
770  * okay to complain about ambiguous-name cases, though, since if we are
771  * working to complain about an invalid name, we've already eliminated that.
772  */
773 static int
775  Alias *eref,
776  const char *colname, int location,
777  int fuzzy_rte_penalty,
778  FuzzyAttrMatchState *fuzzystate)
779 {
780  int result = InvalidAttrNumber;
781  int attnum = 0;
782  ListCell *c;
783 
784  /*
785  * Scan the user column names (or aliases) for a match. Complain if
786  * multiple matches.
787  *
788  * Note: eref->colnames may include entries for dropped columns, but those
789  * will be empty strings that cannot match any legal SQL identifier, so we
790  * don't bother to test for that case here.
791  *
792  * Should this somehow go wrong and we try to access a dropped column,
793  * we'll still catch it by virtue of the check in scanNSItemForColumn().
794  * Callers interested in finding match with shortest distance need to
795  * defend against this directly, though.
796  */
797  foreach(c, eref->colnames)
798  {
799  const char *attcolname = strVal(lfirst(c));
800 
801  attnum++;
802  if (strcmp(attcolname, colname) == 0)
803  {
804  if (result)
805  ereport(ERROR,
806  (errcode(ERRCODE_AMBIGUOUS_COLUMN),
807  errmsg("column reference \"%s\" is ambiguous",
808  colname),
809  parser_errposition(pstate, location)));
810  result = attnum;
811  }
812 
813  /* Update fuzzy match state, if provided. */
814  if (fuzzystate != NULL)
815  updateFuzzyAttrMatchState(fuzzy_rte_penalty, fuzzystate,
816  rte, attcolname, colname, attnum);
817  }
818 
819  /*
820  * If we have a unique match, return it. Note that this allows a user
821  * alias to override a system column name (such as OID) without error.
822  */
823  if (result)
824  return result;
825 
826  /*
827  * If the RTE represents a real relation, consider system column names.
828  * Composites are only used for pseudo-relations like ON CONFLICT's
829  * excluded.
830  */
831  if (rte->rtekind == RTE_RELATION &&
832  rte->relkind != RELKIND_COMPOSITE_TYPE)
833  {
834  /* quick check to see if name could be a system column */
835  attnum = specialAttNum(colname);
836  if (attnum != InvalidAttrNumber)
837  {
838  /* now check to see if column actually is defined */
840  ObjectIdGetDatum(rte->relid),
841  Int16GetDatum(attnum)))
842  result = attnum;
843  }
844  }
845 
846  return result;
847 }
848 
849 /*
850  * colNameToVar
851  * Search for an unqualified column name.
852  * If found, return the appropriate Var node (or expression).
853  * If not found, return NULL. If the name proves ambiguous, raise error.
854  * If localonly is true, only names in the innermost query are considered.
855  */
856 Node *
857 colNameToVar(ParseState *pstate, const char *colname, bool localonly,
858  int location)
859 {
860  Node *result = NULL;
861  int sublevels_up = 0;
862  ParseState *orig_pstate = pstate;
863 
864  while (pstate != NULL)
865  {
866  ListCell *l;
867 
868  foreach(l, pstate->p_namespace)
869  {
871  Node *newresult;
872 
873  /* Ignore table-only items */
874  if (!nsitem->p_cols_visible)
875  continue;
876  /* If not inside LATERAL, ignore lateral-only items */
877  if (nsitem->p_lateral_only && !pstate->p_lateral_active)
878  continue;
879 
880  /* use orig_pstate here for consistency with other callers */
881  newresult = scanNSItemForColumn(orig_pstate, nsitem, sublevels_up,
882  colname, location);
883 
884  if (newresult)
885  {
886  if (result)
887  ereport(ERROR,
888  (errcode(ERRCODE_AMBIGUOUS_COLUMN),
889  errmsg("column reference \"%s\" is ambiguous",
890  colname),
891  parser_errposition(pstate, location)));
892  check_lateral_ref_ok(pstate, nsitem, location);
893  result = newresult;
894  }
895  }
896 
897  if (result != NULL || localonly)
898  break; /* found, or don't want to look at parent */
899 
900  pstate = pstate->parentParseState;
901  sublevels_up++;
902  }
903 
904  return result;
905 }
906 
907 /*
908  * searchRangeTableForCol
909  * See if any RangeTblEntry could possibly provide the given column name (or
910  * find the best match available). Returns state with relevant details.
911  *
912  * This is different from colNameToVar in that it considers every entry in
913  * the ParseState's rangetable(s), not only those that are currently visible
914  * in the p_namespace list(s). This behavior is invalid per the SQL spec,
915  * and it may give ambiguous results (there might be multiple equally valid
916  * matches, but only one will be returned). This must be used ONLY as a
917  * heuristic in giving suitable error messages. See errorMissingColumn.
918  *
919  * This function is also different in that it will consider approximate
920  * matches -- if the user entered an alias/column pair that is only slightly
921  * different from a valid pair, we may be able to infer what they meant to
922  * type and provide a reasonable hint.
923  *
924  * The FuzzyAttrMatchState will have 'rfirst' pointing to the best RTE
925  * containing the most promising match for the alias and column name. If
926  * the alias and column names match exactly, 'first' will be InvalidAttrNumber;
927  * otherwise, it will be the attribute number for the match. In the latter
928  * case, 'rsecond' may point to a second, equally close approximate match,
929  * and 'second' will contain the attribute number for the second match.
930  */
931 static FuzzyAttrMatchState *
932 searchRangeTableForCol(ParseState *pstate, const char *alias, const char *colname,
933  int location)
934 {
935  ParseState *orig_pstate = pstate;
936  FuzzyAttrMatchState *fuzzystate = palloc(sizeof(FuzzyAttrMatchState));
937 
938  fuzzystate->distance = MAX_FUZZY_DISTANCE + 1;
939  fuzzystate->rfirst = NULL;
940  fuzzystate->rsecond = NULL;
941  fuzzystate->first = InvalidAttrNumber;
942  fuzzystate->second = InvalidAttrNumber;
943 
944  while (pstate != NULL)
945  {
946  ListCell *l;
947 
948  foreach(l, pstate->p_rtable)
949  {
950  RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
951  int fuzzy_rte_penalty = 0;
952 
953  /*
954  * Typically, it is not useful to look for matches within join
955  * RTEs; they effectively duplicate other RTEs for our purposes,
956  * and if a match is chosen from a join RTE, an unhelpful alias is
957  * displayed in the final diagnostic message.
958  */
959  if (rte->rtekind == RTE_JOIN)
960  continue;
961 
962  /*
963  * If the user didn't specify an alias, then matches against one
964  * RTE are as good as another. But if the user did specify an
965  * alias, then we want at least a fuzzy - and preferably an exact
966  * - match for the range table entry.
967  */
968  if (alias != NULL)
969  fuzzy_rte_penalty =
970  varstr_levenshtein_less_equal(alias, strlen(alias),
971  rte->eref->aliasname,
972  strlen(rte->eref->aliasname),
973  1, 1, 1,
974  MAX_FUZZY_DISTANCE + 1,
975  true);
976 
977  /*
978  * Scan for a matching column; if we find an exact match, we're
979  * done. Otherwise, update fuzzystate.
980  */
981  if (scanRTEForColumn(orig_pstate, rte, rte->eref, colname, location,
982  fuzzy_rte_penalty, fuzzystate)
983  && fuzzy_rte_penalty == 0)
984  {
985  fuzzystate->rfirst = rte;
986  fuzzystate->first = InvalidAttrNumber;
987  fuzzystate->rsecond = NULL;
988  fuzzystate->second = InvalidAttrNumber;
989  return fuzzystate;
990  }
991  }
992 
993  pstate = pstate->parentParseState;
994  }
995 
996  return fuzzystate;
997 }
998 
999 /*
1000  * markRTEForSelectPriv
1001  * Mark the specified column of the RTE with index rtindex
1002  * as requiring SELECT privilege
1003  *
1004  * col == InvalidAttrNumber means a "whole row" reference
1005  */
1006 static void
1007 markRTEForSelectPriv(ParseState *pstate, int rtindex, AttrNumber col)
1008 {
1009  RangeTblEntry *rte = rt_fetch(rtindex, pstate->p_rtable);
1010 
1011  if (rte->rtekind == RTE_RELATION)
1012  {
1013  /* Make sure the rel as a whole is marked for SELECT access */
1014  rte->requiredPerms |= ACL_SELECT;
1015  /* Must offset the attnum to fit in a bitmapset */
1018  }
1019  else if (rte->rtekind == RTE_JOIN)
1020  {
1021  if (col == InvalidAttrNumber)
1022  {
1023  /*
1024  * A whole-row reference to a join has to be treated as whole-row
1025  * references to the two inputs.
1026  */
1027  JoinExpr *j;
1028 
1029  if (rtindex > 0 && rtindex <= list_length(pstate->p_joinexprs))
1030  j = list_nth_node(JoinExpr, pstate->p_joinexprs, rtindex - 1);
1031  else
1032  j = NULL;
1033  if (j == NULL)
1034  elog(ERROR, "could not find JoinExpr for whole-row reference");
1035 
1036  /* Note: we can't see FromExpr here */
1037  if (IsA(j->larg, RangeTblRef))
1038  {
1039  int varno = ((RangeTblRef *) j->larg)->rtindex;
1040 
1041  markRTEForSelectPriv(pstate, varno, InvalidAttrNumber);
1042  }
1043  else if (IsA(j->larg, JoinExpr))
1044  {
1045  int varno = ((JoinExpr *) j->larg)->rtindex;
1046 
1047  markRTEForSelectPriv(pstate, varno, InvalidAttrNumber);
1048  }
1049  else
1050  elog(ERROR, "unrecognized node type: %d",
1051  (int) nodeTag(j->larg));
1052  if (IsA(j->rarg, RangeTblRef))
1053  {
1054  int varno = ((RangeTblRef *) j->rarg)->rtindex;
1055 
1056  markRTEForSelectPriv(pstate, varno, InvalidAttrNumber);
1057  }
1058  else if (IsA(j->rarg, JoinExpr))
1059  {
1060  int varno = ((JoinExpr *) j->rarg)->rtindex;
1061 
1062  markRTEForSelectPriv(pstate, varno, InvalidAttrNumber);
1063  }
1064  else
1065  elog(ERROR, "unrecognized node type: %d",
1066  (int) nodeTag(j->rarg));
1067  }
1068  else
1069  {
1070  /*
1071  * Join alias Vars for ordinary columns must refer to merged JOIN
1072  * USING columns. We don't need to do anything here, because the
1073  * join input columns will also be referenced in the join's qual
1074  * clause, and will get marked for select privilege there.
1075  */
1076  }
1077  }
1078  /* other RTE types don't require privilege marking */
1079 }
1080 
1081 /*
1082  * markVarForSelectPriv
1083  * Mark the RTE referenced by the Var as requiring SELECT privilege
1084  * for the Var's column (the Var could be a whole-row Var, too)
1085  */
1086 void
1088 {
1089  Index lv;
1090 
1091  Assert(IsA(var, Var));
1092  /* Find the appropriate pstate if it's an uplevel Var */
1093  for (lv = 0; lv < var->varlevelsup; lv++)
1094  pstate = pstate->parentParseState;
1095  markRTEForSelectPriv(pstate, var->varno, var->varattno);
1096 }
1097 
1098 /*
1099  * buildRelationAliases
1100  * Construct the eref column name list for a relation RTE.
1101  * This code is also used for function RTEs.
1102  *
1103  * tupdesc: the physical column information
1104  * alias: the user-supplied alias, or NULL if none
1105  * eref: the eref Alias to store column names in
1106  *
1107  * eref->colnames is filled in. Also, alias->colnames is rebuilt to insert
1108  * empty strings for any dropped columns, so that it will be one-to-one with
1109  * physical column numbers.
1110  *
1111  * It is an error for there to be more aliases present than required.
1112  */
1113 static void
1115 {
1116  int maxattrs = tupdesc->natts;
1117  List *aliaslist;
1118  ListCell *aliaslc;
1119  int numaliases;
1120  int varattno;
1121  int numdropped = 0;
1122 
1123  Assert(eref->colnames == NIL);
1124 
1125  if (alias)
1126  {
1127  aliaslist = alias->colnames;
1128  aliaslc = list_head(aliaslist);
1129  numaliases = list_length(aliaslist);
1130  /* We'll rebuild the alias colname list */
1131  alias->colnames = NIL;
1132  }
1133  else
1134  {
1135  aliaslist = NIL;
1136  aliaslc = NULL;
1137  numaliases = 0;
1138  }
1139 
1140  for (varattno = 0; varattno < maxattrs; varattno++)
1141  {
1142  Form_pg_attribute attr = TupleDescAttr(tupdesc, varattno);
1143  Value *attrname;
1144 
1145  if (attr->attisdropped)
1146  {
1147  /* Always insert an empty string for a dropped column */
1148  attrname = makeString(pstrdup(""));
1149  if (aliaslc)
1150  alias->colnames = lappend(alias->colnames, attrname);
1151  numdropped++;
1152  }
1153  else if (aliaslc)
1154  {
1155  /* Use the next user-supplied alias */
1156  attrname = (Value *) lfirst(aliaslc);
1157  aliaslc = lnext(aliaslist, aliaslc);
1158  alias->colnames = lappend(alias->colnames, attrname);
1159  }
1160  else
1161  {
1162  attrname = makeString(pstrdup(NameStr(attr->attname)));
1163  /* we're done with the alias if any */
1164  }
1165 
1166  eref->colnames = lappend(eref->colnames, attrname);
1167  }
1168 
1169  /* Too many user-supplied aliases? */
1170  if (aliaslc)
1171  ereport(ERROR,
1172  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
1173  errmsg("table \"%s\" has %d columns available but %d columns specified",
1174  eref->aliasname, maxattrs - numdropped, numaliases)));
1175 }
1176 
1177 /*
1178  * chooseScalarFunctionAlias
1179  * Select the column alias for a function in a function RTE,
1180  * when the function returns a scalar type (not composite or RECORD).
1181  *
1182  * funcexpr: transformed expression tree for the function call
1183  * funcname: function name (as determined by FigureColname)
1184  * alias: the user-supplied alias for the RTE, or NULL if none
1185  * nfuncs: the number of functions appearing in the function RTE
1186  *
1187  * Note that the name we choose might be overridden later, if the user-given
1188  * alias includes column alias names. That's of no concern here.
1189  */
1190 static char *
1191 chooseScalarFunctionAlias(Node *funcexpr, char *funcname,
1192  Alias *alias, int nfuncs)
1193 {
1194  char *pname;
1195 
1196  /*
1197  * If the expression is a simple function call, and the function has a
1198  * single OUT parameter that is named, use the parameter's name.
1199  */
1200  if (funcexpr && IsA(funcexpr, FuncExpr))
1201  {
1202  pname = get_func_result_name(((FuncExpr *) funcexpr)->funcid);
1203  if (pname)
1204  return pname;
1205  }
1206 
1207  /*
1208  * If there's just one function in the RTE, and the user gave an RTE alias
1209  * name, use that name. (This makes FROM func() AS foo use "foo" as the
1210  * column name as well as the table alias.)
1211  */
1212  if (nfuncs == 1 && alias)
1213  return alias->aliasname;
1214 
1215  /*
1216  * Otherwise use the function name.
1217  */
1218  return funcname;
1219 }
1220 
1221 /*
1222  * buildNSItemFromTupleDesc
1223  * Build a ParseNamespaceItem, given a tupdesc describing the columns.
1224  *
1225  * rte: the new RangeTblEntry for the rel
1226  * rtindex: its index in the rangetable list
1227  * tupdesc: the physical column information
1228  */
1229 static ParseNamespaceItem *
1231 {
1232  ParseNamespaceItem *nsitem;
1233  ParseNamespaceColumn *nscolumns;
1234  int maxattrs = tupdesc->natts;
1235  int varattno;
1236 
1237  /* colnames must have the same number of entries as the nsitem */
1238  Assert(maxattrs == list_length(rte->eref->colnames));
1239 
1240  /* extract per-column data from the tupdesc */
1241  nscolumns = (ParseNamespaceColumn *)
1242  palloc0(maxattrs * sizeof(ParseNamespaceColumn));
1243 
1244  for (varattno = 0; varattno < maxattrs; varattno++)
1245  {
1246  Form_pg_attribute attr = TupleDescAttr(tupdesc, varattno);
1247 
1248  /* For a dropped column, just leave the entry as zeroes */
1249  if (attr->attisdropped)
1250  continue;
1251 
1252  nscolumns[varattno].p_varno = rtindex;
1253  nscolumns[varattno].p_varattno = varattno + 1;
1254  nscolumns[varattno].p_vartype = attr->atttypid;
1255  nscolumns[varattno].p_vartypmod = attr->atttypmod;
1256  nscolumns[varattno].p_varcollid = attr->attcollation;
1257  nscolumns[varattno].p_varnosyn = rtindex;
1258  nscolumns[varattno].p_varattnosyn = varattno + 1;
1259  }
1260 
1261  /* ... and build the nsitem */
1262  nsitem = (ParseNamespaceItem *) palloc(sizeof(ParseNamespaceItem));
1263  nsitem->p_names = rte->eref;
1264  nsitem->p_rte = rte;
1265  nsitem->p_rtindex = rtindex;
1266  nsitem->p_nscolumns = nscolumns;
1267  /* set default visibility flags; might get changed later */
1268  nsitem->p_rel_visible = true;
1269  nsitem->p_cols_visible = true;
1270  nsitem->p_lateral_only = false;
1271  nsitem->p_lateral_ok = true;
1272 
1273  return nsitem;
1274 }
1275 
1276 /*
1277  * buildNSItemFromLists
1278  * Build a ParseNamespaceItem, given column type information in lists.
1279  *
1280  * rte: the new RangeTblEntry for the rel
1281  * rtindex: its index in the rangetable list
1282  * coltypes: per-column datatype OIDs
1283  * coltypmods: per-column type modifiers
1284  * colcollation: per-column collation OIDs
1285  */
1286 static ParseNamespaceItem *
1288  List *coltypes, List *coltypmods, List *colcollations)
1289 {
1290  ParseNamespaceItem *nsitem;
1291  ParseNamespaceColumn *nscolumns;
1292  int maxattrs = list_length(coltypes);
1293  int varattno;
1294  ListCell *lct;
1295  ListCell *lcm;
1296  ListCell *lcc;
1297 
1298  /* colnames must have the same number of entries as the nsitem */
1299  Assert(maxattrs == list_length(rte->eref->colnames));
1300 
1301  Assert(maxattrs == list_length(coltypmods));
1302  Assert(maxattrs == list_length(colcollations));
1303 
1304  /* extract per-column data from the lists */
1305  nscolumns = (ParseNamespaceColumn *)
1306  palloc0(maxattrs * sizeof(ParseNamespaceColumn));
1307 
1308  varattno = 0;
1309  forthree(lct, coltypes,
1310  lcm, coltypmods,
1311  lcc, colcollations)
1312  {
1313  nscolumns[varattno].p_varno = rtindex;
1314  nscolumns[varattno].p_varattno = varattno + 1;
1315  nscolumns[varattno].p_vartype = lfirst_oid(lct);
1316  nscolumns[varattno].p_vartypmod = lfirst_int(lcm);
1317  nscolumns[varattno].p_varcollid = lfirst_oid(lcc);
1318  nscolumns[varattno].p_varnosyn = rtindex;
1319  nscolumns[varattno].p_varattnosyn = varattno + 1;
1320  varattno++;
1321  }
1322 
1323  /* ... and build the nsitem */
1324  nsitem = (ParseNamespaceItem *) palloc(sizeof(ParseNamespaceItem));
1325  nsitem->p_names = rte->eref;
1326  nsitem->p_rte = rte;
1327  nsitem->p_rtindex = rtindex;
1328  nsitem->p_nscolumns = nscolumns;
1329  /* set default visibility flags; might get changed later */
1330  nsitem->p_rel_visible = true;
1331  nsitem->p_cols_visible = true;
1332  nsitem->p_lateral_only = false;
1333  nsitem->p_lateral_ok = true;
1334 
1335  return nsitem;
1336 }
1337 
1338 /*
1339  * Open a table during parse analysis
1340  *
1341  * This is essentially just the same as table_openrv(), except that it caters
1342  * to some parser-specific error reporting needs, notably that it arranges
1343  * to include the RangeVar's parse location in any resulting error.
1344  *
1345  * Note: properly, lockmode should be declared LOCKMODE not int, but that
1346  * would require importing storage/lock.h into parse_relation.h. Since
1347  * LOCKMODE is typedef'd as int anyway, that seems like overkill.
1348  */
1349 Relation
1350 parserOpenTable(ParseState *pstate, const RangeVar *relation, int lockmode)
1351 {
1352  Relation rel;
1353  ParseCallbackState pcbstate;
1354 
1355  setup_parser_errposition_callback(&pcbstate, pstate, relation->location);
1356  rel = table_openrv_extended(relation, lockmode, true);
1357  if (rel == NULL)
1358  {
1359  if (relation->schemaname)
1360  ereport(ERROR,
1362  errmsg("relation \"%s.%s\" does not exist",
1363  relation->schemaname, relation->relname)));
1364  else
1365  {
1366  /*
1367  * An unqualified name might have been meant as a reference to
1368  * some not-yet-in-scope CTE. The bare "does not exist" message
1369  * has proven remarkably unhelpful for figuring out such problems,
1370  * so we take pains to offer a specific hint.
1371  */
1372  if (isFutureCTE(pstate, relation->relname))
1373  ereport(ERROR,
1375  errmsg("relation \"%s\" does not exist",
1376  relation->relname),
1377  errdetail("There is a WITH item named \"%s\", but it cannot be referenced from this part of the query.",
1378  relation->relname),
1379  errhint("Use WITH RECURSIVE, or re-order the WITH items to remove forward references.")));
1380  else
1381  ereport(ERROR,
1383  errmsg("relation \"%s\" does not exist",
1384  relation->relname)));
1385  }
1386  }
1388  return rel;
1389 }
1390 
1391 /*
1392  * Add an entry for a relation to the pstate's range table (p_rtable).
1393  * Then, construct and return a ParseNamespaceItem for the new RTE.
1394  *
1395  * We do not link the ParseNamespaceItem into the pstate here; it's the
1396  * caller's job to do that in the appropriate way.
1397  *
1398  * Note: formerly this checked for refname conflicts, but that's wrong.
1399  * Caller is responsible for checking for conflicts in the appropriate scope.
1400  */
1403  RangeVar *relation,
1404  Alias *alias,
1405  bool inh,
1406  bool inFromCl)
1407 {
1409  char *refname = alias ? alias->aliasname : relation->relname;
1410  LOCKMODE lockmode;
1411  Relation rel;
1412  ParseNamespaceItem *nsitem;
1413 
1414  Assert(pstate != NULL);
1415 
1416  rte->rtekind = RTE_RELATION;
1417  rte->alias = alias;
1418 
1419  /*
1420  * Identify the type of lock we'll need on this relation. It's not the
1421  * query's target table (that case is handled elsewhere), so we need
1422  * either RowShareLock if it's locked by FOR UPDATE/SHARE, or plain
1423  * AccessShareLock otherwise.
1424  */
1425  lockmode = isLockedRefname(pstate, refname) ? RowShareLock : AccessShareLock;
1426 
1427  /*
1428  * Get the rel's OID. This access also ensures that we have an up-to-date
1429  * relcache entry for the rel. Since this is typically the first access
1430  * to a rel in a statement, we must open the rel with the proper lockmode.
1431  */
1432  rel = parserOpenTable(pstate, relation, lockmode);
1433  rte->relid = RelationGetRelid(rel);
1434  rte->relkind = rel->rd_rel->relkind;
1435  rte->rellockmode = lockmode;
1436 
1437  /*
1438  * Build the list of effective column names using user-supplied aliases
1439  * and/or actual column names.
1440  */
1441  rte->eref = makeAlias(refname, NIL);
1442  buildRelationAliases(rel->rd_att, alias, rte->eref);
1443 
1444  /*
1445  * Set flags and access permissions.
1446  *
1447  * The initial default on access checks is always check-for-READ-access,
1448  * which is the right thing for all except target tables.
1449  */
1450  rte->lateral = false;
1451  rte->inh = inh;
1452  rte->inFromCl = inFromCl;
1453 
1454  rte->requiredPerms = ACL_SELECT;
1455  rte->checkAsUser = InvalidOid; /* not set-uid by default, either */
1456  rte->selectedCols = NULL;
1457  rte->insertedCols = NULL;
1458  rte->updatedCols = NULL;
1459  rte->extraUpdatedCols = NULL;
1460 
1461  /*
1462  * Add completed RTE to pstate's range table list, so that we know its
1463  * index. But we don't add it to the join list --- caller must do that if
1464  * appropriate.
1465  */
1466  pstate->p_rtable = lappend(pstate->p_rtable, rte);
1467 
1468  /*
1469  * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
1470  * list --- caller must do that if appropriate.
1471  */
1472  nsitem = buildNSItemFromTupleDesc(rte, list_length(pstate->p_rtable),
1473  rel->rd_att);
1474 
1475  /*
1476  * Drop the rel refcount, but keep the access lock till end of transaction
1477  * so that the table can't be deleted or have its schema modified
1478  * underneath us.
1479  */
1480  table_close(rel, NoLock);
1481 
1482  return nsitem;
1483 }
1484 
1485 /*
1486  * Add an entry for a relation to the pstate's range table (p_rtable).
1487  * Then, construct and return a ParseNamespaceItem for the new RTE.
1488  *
1489  * This is just like addRangeTableEntry() except that it makes an RTE
1490  * given an already-open relation instead of a RangeVar reference.
1491  *
1492  * lockmode is the lock type required for query execution; it must be one
1493  * of AccessShareLock, RowShareLock, or RowExclusiveLock depending on the
1494  * RTE's role within the query. The caller must hold that lock mode
1495  * or a stronger one.
1496  *
1497  * Note: properly, lockmode should be declared LOCKMODE not int, but that
1498  * would require importing storage/lock.h into parse_relation.h. Since
1499  * LOCKMODE is typedef'd as int anyway, that seems like overkill.
1500  */
1503  Relation rel,
1504  int lockmode,
1505  Alias *alias,
1506  bool inh,
1507  bool inFromCl)
1508 {
1510  char *refname = alias ? alias->aliasname : RelationGetRelationName(rel);
1511 
1512  Assert(pstate != NULL);
1513 
1514  Assert(lockmode == AccessShareLock ||
1515  lockmode == RowShareLock ||
1516  lockmode == RowExclusiveLock);
1517  Assert(CheckRelationLockedByMe(rel, lockmode, true));
1518 
1519  rte->rtekind = RTE_RELATION;
1520  rte->alias = alias;
1521  rte->relid = RelationGetRelid(rel);
1522  rte->relkind = rel->rd_rel->relkind;
1523  rte->rellockmode = lockmode;
1524 
1525  /*
1526  * Build the list of effective column names using user-supplied aliases
1527  * and/or actual column names.
1528  */
1529  rte->eref = makeAlias(refname, NIL);
1530  buildRelationAliases(rel->rd_att, alias, rte->eref);
1531 
1532  /*
1533  * Set flags and access permissions.
1534  *
1535  * The initial default on access checks is always check-for-READ-access,
1536  * which is the right thing for all except target tables.
1537  */
1538  rte->lateral = false;
1539  rte->inh = inh;
1540  rte->inFromCl = inFromCl;
1541 
1542  rte->requiredPerms = ACL_SELECT;
1543  rte->checkAsUser = InvalidOid; /* not set-uid by default, either */
1544  rte->selectedCols = NULL;
1545  rte->insertedCols = NULL;
1546  rte->updatedCols = NULL;
1547  rte->extraUpdatedCols = NULL;
1548 
1549  /*
1550  * Add completed RTE to pstate's range table list, so that we know its
1551  * index. But we don't add it to the join list --- caller must do that if
1552  * appropriate.
1553  */
1554  pstate->p_rtable = lappend(pstate->p_rtable, rte);
1555 
1556  /*
1557  * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
1558  * list --- caller must do that if appropriate.
1559  */
1560  return buildNSItemFromTupleDesc(rte, list_length(pstate->p_rtable),
1561  rel->rd_att);
1562 }
1563 
1564 /*
1565  * Add an entry for a subquery to the pstate's range table (p_rtable).
1566  * Then, construct and return a ParseNamespaceItem for the new RTE.
1567  *
1568  * This is much like addRangeTableEntry() except that it makes a subquery RTE.
1569  * Note that an alias clause *must* be supplied.
1570  */
1573  Query *subquery,
1574  Alias *alias,
1575  bool lateral,
1576  bool inFromCl)
1577 {
1579  char *refname = alias->aliasname;
1580  Alias *eref;
1581  int numaliases;
1582  List *coltypes,
1583  *coltypmods,
1584  *colcollations;
1585  int varattno;
1586  ListCell *tlistitem;
1587 
1588  Assert(pstate != NULL);
1589 
1590  rte->rtekind = RTE_SUBQUERY;
1591  rte->subquery = subquery;
1592  rte->alias = alias;
1593 
1594  eref = copyObject(alias);
1595  numaliases = list_length(eref->colnames);
1596 
1597  /* fill in any unspecified alias columns, and extract column type info */
1598  coltypes = coltypmods = colcollations = NIL;
1599  varattno = 0;
1600  foreach(tlistitem, subquery->targetList)
1601  {
1602  TargetEntry *te = (TargetEntry *) lfirst(tlistitem);
1603 
1604  if (te->resjunk)
1605  continue;
1606  varattno++;
1607  Assert(varattno == te->resno);
1608  if (varattno > numaliases)
1609  {
1610  char *attrname;
1611 
1612  attrname = pstrdup(te->resname);
1613  eref->colnames = lappend(eref->colnames, makeString(attrname));
1614  }
1615  coltypes = lappend_oid(coltypes,
1616  exprType((Node *) te->expr));
1617  coltypmods = lappend_int(coltypmods,
1618  exprTypmod((Node *) te->expr));
1619  colcollations = lappend_oid(colcollations,
1620  exprCollation((Node *) te->expr));
1621  }
1622  if (varattno < numaliases)
1623  ereport(ERROR,
1624  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
1625  errmsg("table \"%s\" has %d columns available but %d columns specified",
1626  refname, varattno, numaliases)));
1627 
1628  rte->eref = eref;
1629 
1630  /*
1631  * Set flags and access permissions.
1632  *
1633  * Subqueries are never checked for access rights.
1634  */
1635  rte->lateral = lateral;
1636  rte->inh = false; /* never true for subqueries */
1637  rte->inFromCl = inFromCl;
1638 
1639  rte->requiredPerms = 0;
1640  rte->checkAsUser = InvalidOid;
1641  rte->selectedCols = NULL;
1642  rte->insertedCols = NULL;
1643  rte->updatedCols = NULL;
1644  rte->extraUpdatedCols = NULL;
1645 
1646  /*
1647  * Add completed RTE to pstate's range table list, so that we know its
1648  * index. But we don't add it to the join list --- caller must do that if
1649  * appropriate.
1650  */
1651  pstate->p_rtable = lappend(pstate->p_rtable, rte);
1652 
1653  /*
1654  * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
1655  * list --- caller must do that if appropriate.
1656  */
1657  return buildNSItemFromLists(rte, list_length(pstate->p_rtable),
1658  coltypes, coltypmods, colcollations);
1659 }
1660 
1661 /*
1662  * Add an entry for a function (or functions) to the pstate's range table
1663  * (p_rtable). Then, construct and return a ParseNamespaceItem for the new RTE.
1664  *
1665  * This is much like addRangeTableEntry() except that it makes a function RTE.
1666  */
1669  List *funcnames,
1670  List *funcexprs,
1671  List *coldeflists,
1672  RangeFunction *rangefunc,
1673  bool lateral,
1674  bool inFromCl)
1675 {
1677  Alias *alias = rangefunc->alias;
1678  Alias *eref;
1679  char *aliasname;
1680  int nfuncs = list_length(funcexprs);
1681  TupleDesc *functupdescs;
1682  TupleDesc tupdesc;
1683  ListCell *lc1,
1684  *lc2,
1685  *lc3;
1686  int i;
1687  int j;
1688  int funcno;
1689  int natts,
1690  totalatts;
1691 
1692  Assert(pstate != NULL);
1693 
1694  rte->rtekind = RTE_FUNCTION;
1695  rte->relid = InvalidOid;
1696  rte->subquery = NULL;
1697  rte->functions = NIL; /* we'll fill this list below */
1698  rte->funcordinality = rangefunc->ordinality;
1699  rte->alias = alias;
1700 
1701  /*
1702  * Choose the RTE alias name. We default to using the first function's
1703  * name even when there's more than one; which is maybe arguable but beats
1704  * using something constant like "table".
1705  */
1706  if (alias)
1707  aliasname = alias->aliasname;
1708  else
1709  aliasname = linitial(funcnames);
1710 
1711  eref = makeAlias(aliasname, NIL);
1712  rte->eref = eref;
1713 
1714  /* Process each function ... */
1715  functupdescs = (TupleDesc *) palloc(nfuncs * sizeof(TupleDesc));
1716 
1717  totalatts = 0;
1718  funcno = 0;
1719  forthree(lc1, funcexprs, lc2, funcnames, lc3, coldeflists)
1720  {
1721  Node *funcexpr = (Node *) lfirst(lc1);
1722  char *funcname = (char *) lfirst(lc2);
1723  List *coldeflist = (List *) lfirst(lc3);
1725  TypeFuncClass functypclass;
1726  Oid funcrettype;
1727 
1728  /* Initialize RangeTblFunction node */
1729  rtfunc->funcexpr = funcexpr;
1730  rtfunc->funccolnames = NIL;
1731  rtfunc->funccoltypes = NIL;
1732  rtfunc->funccoltypmods = NIL;
1733  rtfunc->funccolcollations = NIL;
1734  rtfunc->funcparams = NULL; /* not set until planning */
1735 
1736  /*
1737  * Now determine if the function returns a simple or composite type.
1738  */
1739  functypclass = get_expr_result_type(funcexpr,
1740  &funcrettype,
1741  &tupdesc);
1742 
1743  /*
1744  * A coldeflist is required if the function returns RECORD and hasn't
1745  * got a predetermined record type, and is prohibited otherwise. This
1746  * can be a bit confusing, so we expend some effort on delivering a
1747  * relevant error message.
1748  */
1749  if (coldeflist != NIL)
1750  {
1751  switch (functypclass)
1752  {
1753  case TYPEFUNC_RECORD:
1754  /* ok */
1755  break;
1756  case TYPEFUNC_COMPOSITE:
1758 
1759  /*
1760  * If the function's raw result type is RECORD, we must
1761  * have resolved it using its OUT parameters. Otherwise,
1762  * it must have a named composite type.
1763  */
1764  if (exprType(funcexpr) == RECORDOID)
1765  ereport(ERROR,
1766  (errcode(ERRCODE_SYNTAX_ERROR),
1767  errmsg("a column definition list is redundant for a function with OUT parameters"),
1768  parser_errposition(pstate,
1769  exprLocation((Node *) coldeflist))));
1770  else
1771  ereport(ERROR,
1772  (errcode(ERRCODE_SYNTAX_ERROR),
1773  errmsg("a column definition list is redundant for a function returning a named composite type"),
1774  parser_errposition(pstate,
1775  exprLocation((Node *) coldeflist))));
1776  break;
1777  default:
1778  ereport(ERROR,
1779  (errcode(ERRCODE_SYNTAX_ERROR),
1780  errmsg("a column definition list is only allowed for functions returning \"record\""),
1781  parser_errposition(pstate,
1782  exprLocation((Node *) coldeflist))));
1783  break;
1784  }
1785  }
1786  else
1787  {
1788  if (functypclass == TYPEFUNC_RECORD)
1789  ereport(ERROR,
1790  (errcode(ERRCODE_SYNTAX_ERROR),
1791  errmsg("a column definition list is required for functions returning \"record\""),
1792  parser_errposition(pstate, exprLocation(funcexpr))));
1793  }
1794 
1795  if (functypclass == TYPEFUNC_COMPOSITE ||
1796  functypclass == TYPEFUNC_COMPOSITE_DOMAIN)
1797  {
1798  /* Composite data type, e.g. a table's row type */
1799  Assert(tupdesc);
1800  }
1801  else if (functypclass == TYPEFUNC_SCALAR)
1802  {
1803  /* Base data type, i.e. scalar */
1804  tupdesc = CreateTemplateTupleDesc(1);
1805  TupleDescInitEntry(tupdesc,
1806  (AttrNumber) 1,
1807  chooseScalarFunctionAlias(funcexpr, funcname,
1808  alias, nfuncs),
1809  funcrettype,
1810  exprTypmod(funcexpr),
1811  0);
1813  (AttrNumber) 1,
1814  exprCollation(funcexpr));
1815  }
1816  else if (functypclass == TYPEFUNC_RECORD)
1817  {
1818  ListCell *col;
1819 
1820  /*
1821  * Use the column definition list to construct a tupdesc and fill
1822  * in the RangeTblFunction's lists.
1823  */
1824  tupdesc = CreateTemplateTupleDesc(list_length(coldeflist));
1825  i = 1;
1826  foreach(col, coldeflist)
1827  {
1828  ColumnDef *n = (ColumnDef *) lfirst(col);
1829  char *attrname;
1830  Oid attrtype;
1831  int32 attrtypmod;
1832  Oid attrcollation;
1833 
1834  attrname = n->colname;
1835  if (n->typeName->setof)
1836  ereport(ERROR,
1837  (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
1838  errmsg("column \"%s\" cannot be declared SETOF",
1839  attrname),
1840  parser_errposition(pstate, n->location)));
1841  typenameTypeIdAndMod(pstate, n->typeName,
1842  &attrtype, &attrtypmod);
1843  attrcollation = GetColumnDefCollation(pstate, n, attrtype);
1844  TupleDescInitEntry(tupdesc,
1845  (AttrNumber) i,
1846  attrname,
1847  attrtype,
1848  attrtypmod,
1849  0);
1851  (AttrNumber) i,
1852  attrcollation);
1853  rtfunc->funccolnames = lappend(rtfunc->funccolnames,
1854  makeString(pstrdup(attrname)));
1855  rtfunc->funccoltypes = lappend_oid(rtfunc->funccoltypes,
1856  attrtype);
1857  rtfunc->funccoltypmods = lappend_int(rtfunc->funccoltypmods,
1858  attrtypmod);
1860  attrcollation);
1861 
1862  i++;
1863  }
1864 
1865  /*
1866  * Ensure that the coldeflist defines a legal set of names (no
1867  * duplicates, but we needn't worry about system column names) and
1868  * datatypes. Although we mostly can't allow pseudo-types, it
1869  * seems safe to allow RECORD and RECORD[], since values within
1870  * those type classes are self-identifying at runtime, and the
1871  * coldeflist doesn't represent anything that will be visible to
1872  * other sessions.
1873  */
1874  CheckAttributeNamesTypes(tupdesc, RELKIND_COMPOSITE_TYPE,
1876  }
1877  else
1878  ereport(ERROR,
1879  (errcode(ERRCODE_DATATYPE_MISMATCH),
1880  errmsg("function \"%s\" in FROM has unsupported return type %s",
1881  funcname, format_type_be(funcrettype)),
1882  parser_errposition(pstate, exprLocation(funcexpr))));
1883 
1884  /* Finish off the RangeTblFunction and add it to the RTE's list */
1885  rtfunc->funccolcount = tupdesc->natts;
1886  rte->functions = lappend(rte->functions, rtfunc);
1887 
1888  /* Save the tupdesc for use below */
1889  functupdescs[funcno] = tupdesc;
1890  totalatts += tupdesc->natts;
1891  funcno++;
1892  }
1893 
1894  /*
1895  * If there's more than one function, or we want an ordinality column, we
1896  * have to produce a merged tupdesc.
1897  */
1898  if (nfuncs > 1 || rangefunc->ordinality)
1899  {
1900  if (rangefunc->ordinality)
1901  totalatts++;
1902 
1903  /* Merge the tuple descs of each function into a composite one */
1904  tupdesc = CreateTemplateTupleDesc(totalatts);
1905  natts = 0;
1906  for (i = 0; i < nfuncs; i++)
1907  {
1908  for (j = 1; j <= functupdescs[i]->natts; j++)
1909  TupleDescCopyEntry(tupdesc, ++natts, functupdescs[i], j);
1910  }
1911 
1912  /* Add the ordinality column if needed */
1913  if (rangefunc->ordinality)
1914  {
1915  TupleDescInitEntry(tupdesc,
1916  (AttrNumber) ++natts,
1917  "ordinality",
1918  INT8OID,
1919  -1,
1920  0);
1921  /* no need to set collation */
1922  }
1923 
1924  Assert(natts == totalatts);
1925  }
1926  else
1927  {
1928  /* We can just use the single function's tupdesc as-is */
1929  tupdesc = functupdescs[0];
1930  }
1931 
1932  /* Use the tupdesc while assigning column aliases for the RTE */
1933  buildRelationAliases(tupdesc, alias, eref);
1934 
1935  /*
1936  * Set flags and access permissions.
1937  *
1938  * Functions are never checked for access rights (at least, not by the RTE
1939  * permissions mechanism).
1940  */
1941  rte->lateral = lateral;
1942  rte->inh = false; /* never true for functions */
1943  rte->inFromCl = inFromCl;
1944 
1945  rte->requiredPerms = 0;
1946  rte->checkAsUser = InvalidOid;
1947  rte->selectedCols = NULL;
1948  rte->insertedCols = NULL;
1949  rte->updatedCols = NULL;
1950  rte->extraUpdatedCols = NULL;
1951 
1952  /*
1953  * Add completed RTE to pstate's range table list, so that we know its
1954  * index. But we don't add it to the join list --- caller must do that if
1955  * appropriate.
1956  */
1957  pstate->p_rtable = lappend(pstate->p_rtable, rte);
1958 
1959  /*
1960  * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
1961  * list --- caller must do that if appropriate.
1962  */
1963  return buildNSItemFromTupleDesc(rte, list_length(pstate->p_rtable),
1964  tupdesc);
1965 }
1966 
1967 /*
1968  * Add an entry for a table function to the pstate's range table (p_rtable).
1969  * Then, construct and return a ParseNamespaceItem for the new RTE.
1970  *
1971  * This is much like addRangeTableEntry() except that it makes a tablefunc RTE.
1972  */
1975  TableFunc *tf,
1976  Alias *alias,
1977  bool lateral,
1978  bool inFromCl)
1979 {
1981  char *refname = alias ? alias->aliasname : pstrdup("xmltable");
1982  Alias *eref;
1983  int numaliases;
1984 
1985  Assert(pstate != NULL);
1986 
1987  rte->rtekind = RTE_TABLEFUNC;
1988  rte->relid = InvalidOid;
1989  rte->subquery = NULL;
1990  rte->tablefunc = tf;
1991  rte->coltypes = tf->coltypes;
1992  rte->coltypmods = tf->coltypmods;
1993  rte->colcollations = tf->colcollations;
1994  rte->alias = alias;
1995 
1996  eref = alias ? copyObject(alias) : makeAlias(refname, NIL);
1997  numaliases = list_length(eref->colnames);
1998 
1999  /* fill in any unspecified alias columns */
2000  if (numaliases < list_length(tf->colnames))
2001  eref->colnames = list_concat(eref->colnames,
2002  list_copy_tail(tf->colnames, numaliases));
2003 
2004  rte->eref = eref;
2005 
2006  /*
2007  * Set flags and access permissions.
2008  *
2009  * Tablefuncs are never checked for access rights (at least, not by the
2010  * RTE permissions mechanism).
2011  */
2012  rte->lateral = lateral;
2013  rte->inh = false; /* never true for tablefunc RTEs */
2014  rte->inFromCl = inFromCl;
2015 
2016  rte->requiredPerms = 0;
2017  rte->checkAsUser = InvalidOid;
2018  rte->selectedCols = NULL;
2019  rte->insertedCols = NULL;
2020  rte->updatedCols = NULL;
2021  rte->extraUpdatedCols = NULL;
2022 
2023  /*
2024  * Add completed RTE to pstate's range table list, so that we know its
2025  * index. But we don't add it to the join list --- caller must do that if
2026  * appropriate.
2027  */
2028  pstate->p_rtable = lappend(pstate->p_rtable, rte);
2029 
2030  /*
2031  * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
2032  * list --- caller must do that if appropriate.
2033  */
2034  return buildNSItemFromLists(rte, list_length(pstate->p_rtable),
2035  rte->coltypes, rte->coltypmods,
2036  rte->colcollations);
2037 }
2038 
2039 /*
2040  * Add an entry for a VALUES list to the pstate's range table (p_rtable).
2041  * Then, construct and return a ParseNamespaceItem for the new RTE.
2042  *
2043  * This is much like addRangeTableEntry() except that it makes a values RTE.
2044  */
2047  List *exprs,
2048  List *coltypes,
2049  List *coltypmods,
2050  List *colcollations,
2051  Alias *alias,
2052  bool lateral,
2053  bool inFromCl)
2054 {
2056  char *refname = alias ? alias->aliasname : pstrdup("*VALUES*");
2057  Alias *eref;
2058  int numaliases;
2059  int numcolumns;
2060 
2061  Assert(pstate != NULL);
2062 
2063  rte->rtekind = RTE_VALUES;
2064  rte->relid = InvalidOid;
2065  rte->subquery = NULL;
2066  rte->values_lists = exprs;
2067  rte->coltypes = coltypes;
2068  rte->coltypmods = coltypmods;
2069  rte->colcollations = colcollations;
2070  rte->alias = alias;
2071 
2072  eref = alias ? copyObject(alias) : makeAlias(refname, NIL);
2073 
2074  /* fill in any unspecified alias columns */
2075  numcolumns = list_length((List *) linitial(exprs));
2076  numaliases = list_length(eref->colnames);
2077  while (numaliases < numcolumns)
2078  {
2079  char attrname[64];
2080 
2081  numaliases++;
2082  snprintf(attrname, sizeof(attrname), "column%d", numaliases);
2083  eref->colnames = lappend(eref->colnames,
2084  makeString(pstrdup(attrname)));
2085  }
2086  if (numcolumns < numaliases)
2087  ereport(ERROR,
2088  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
2089  errmsg("VALUES lists \"%s\" have %d columns available but %d columns specified",
2090  refname, numcolumns, numaliases)));
2091 
2092  rte->eref = eref;
2093 
2094  /*
2095  * Set flags and access permissions.
2096  *
2097  * Subqueries are never checked for access rights.
2098  */
2099  rte->lateral = lateral;
2100  rte->inh = false; /* never true for values RTEs */
2101  rte->inFromCl = inFromCl;
2102 
2103  rte->requiredPerms = 0;
2104  rte->checkAsUser = InvalidOid;
2105  rte->selectedCols = NULL;
2106  rte->insertedCols = NULL;
2107  rte->updatedCols = NULL;
2108  rte->extraUpdatedCols = NULL;
2109 
2110  /*
2111  * Add completed RTE to pstate's range table list, so that we know its
2112  * index. But we don't add it to the join list --- caller must do that if
2113  * appropriate.
2114  */
2115  pstate->p_rtable = lappend(pstate->p_rtable, rte);
2116 
2117  /*
2118  * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
2119  * list --- caller must do that if appropriate.
2120  */
2121  return buildNSItemFromLists(rte, list_length(pstate->p_rtable),
2122  rte->coltypes, rte->coltypmods,
2123  rte->colcollations);
2124 }
2125 
2126 /*
2127  * Add an entry for a join to the pstate's range table (p_rtable).
2128  * Then, construct and return a ParseNamespaceItem for the new RTE.
2129  *
2130  * This is much like addRangeTableEntry() except that it makes a join RTE.
2131  * Also, it's more convenient for the caller to construct the
2132  * ParseNamespaceColumn array, so we pass that in.
2133  */
2136  List *colnames,
2137  ParseNamespaceColumn *nscolumns,
2138  JoinType jointype,
2139  int nummergedcols,
2140  List *aliasvars,
2141  List *leftcols,
2142  List *rightcols,
2143  Alias *join_using_alias,
2144  Alias *alias,
2145  bool inFromCl)
2146 {
2148  Alias *eref;
2149  int numaliases;
2150  ParseNamespaceItem *nsitem;
2151 
2152  Assert(pstate != NULL);
2153 
2154  /*
2155  * Fail if join has too many columns --- we must be able to reference any
2156  * of the columns with an AttrNumber.
2157  */
2158  if (list_length(aliasvars) > MaxAttrNumber)
2159  ereport(ERROR,
2160  (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
2161  errmsg("joins can have at most %d columns",
2162  MaxAttrNumber)));
2163 
2164  rte->rtekind = RTE_JOIN;
2165  rte->relid = InvalidOid;
2166  rte->subquery = NULL;
2167  rte->jointype = jointype;
2168  rte->joinmergedcols = nummergedcols;
2169  rte->joinaliasvars = aliasvars;
2170  rte->joinleftcols = leftcols;
2171  rte->joinrightcols = rightcols;
2172  rte->join_using_alias = join_using_alias;
2173  rte->alias = alias;
2174 
2175  eref = alias ? copyObject(alias) : makeAlias("unnamed_join", NIL);
2176  numaliases = list_length(eref->colnames);
2177 
2178  /* fill in any unspecified alias columns */
2179  if (numaliases < list_length(colnames))
2180  eref->colnames = list_concat(eref->colnames,
2181  list_copy_tail(colnames, numaliases));
2182 
2183  rte->eref = eref;
2184 
2185  /*
2186  * Set flags and access permissions.
2187  *
2188  * Joins are never checked for access rights.
2189  */
2190  rte->lateral = false;
2191  rte->inh = false; /* never true for joins */
2192  rte->inFromCl = inFromCl;
2193 
2194  rte->requiredPerms = 0;
2195  rte->checkAsUser = InvalidOid;
2196  rte->selectedCols = NULL;
2197  rte->insertedCols = NULL;
2198  rte->updatedCols = NULL;
2199  rte->extraUpdatedCols = NULL;
2200 
2201  /*
2202  * Add completed RTE to pstate's range table list, so that we know its
2203  * index. But we don't add it to the join list --- caller must do that if
2204  * appropriate.
2205  */
2206  pstate->p_rtable = lappend(pstate->p_rtable, rte);
2207 
2208  /*
2209  * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
2210  * list --- caller must do that if appropriate.
2211  */
2212  nsitem = (ParseNamespaceItem *) palloc(sizeof(ParseNamespaceItem));
2213  nsitem->p_names = rte->eref;
2214  nsitem->p_rte = rte;
2215  nsitem->p_rtindex = list_length(pstate->p_rtable);
2216  nsitem->p_nscolumns = nscolumns;
2217  /* set default visibility flags; might get changed later */
2218  nsitem->p_rel_visible = true;
2219  nsitem->p_cols_visible = true;
2220  nsitem->p_lateral_only = false;
2221  nsitem->p_lateral_ok = true;
2222 
2223  return nsitem;
2224 }
2225 
2226 /*
2227  * Add an entry for a CTE reference to the pstate's range table (p_rtable).
2228  * Then, construct and return a ParseNamespaceItem for the new RTE.
2229  *
2230  * This is much like addRangeTableEntry() except that it makes a CTE RTE.
2231  */
2234  CommonTableExpr *cte,
2235  Index levelsup,
2236  RangeVar *rv,
2237  bool inFromCl)
2238 {
2240  Alias *alias = rv->alias;
2241  char *refname = alias ? alias->aliasname : cte->ctename;
2242  Alias *eref;
2243  int numaliases;
2244  int varattno;
2245  ListCell *lc;
2246  int n_dontexpand_columns = 0;
2247  ParseNamespaceItem *psi;
2248 
2249  Assert(pstate != NULL);
2250 
2251  rte->rtekind = RTE_CTE;
2252  rte->ctename = cte->ctename;
2253  rte->ctelevelsup = levelsup;
2254 
2255  /* Self-reference if and only if CTE's parse analysis isn't completed */
2256  rte->self_reference = !IsA(cte->ctequery, Query);
2257  Assert(cte->cterecursive || !rte->self_reference);
2258  /* Bump the CTE's refcount if this isn't a self-reference */
2259  if (!rte->self_reference)
2260  cte->cterefcount++;
2261 
2262  /*
2263  * We throw error if the CTE is INSERT/UPDATE/DELETE without RETURNING.
2264  * This won't get checked in case of a self-reference, but that's OK
2265  * because data-modifying CTEs aren't allowed to be recursive anyhow.
2266  */
2267  if (IsA(cte->ctequery, Query))
2268  {
2269  Query *ctequery = (Query *) cte->ctequery;
2270 
2271  if (ctequery->commandType != CMD_SELECT &&
2272  ctequery->returningList == NIL)
2273  ereport(ERROR,
2274  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2275  errmsg("WITH query \"%s\" does not have a RETURNING clause",
2276  cte->ctename),
2277  parser_errposition(pstate, rv->location)));
2278  }
2279 
2280  rte->coltypes = list_copy(cte->ctecoltypes);
2281  rte->coltypmods = list_copy(cte->ctecoltypmods);
2283 
2284  rte->alias = alias;
2285  if (alias)
2286  eref = copyObject(alias);
2287  else
2288  eref = makeAlias(refname, NIL);
2289  numaliases = list_length(eref->colnames);
2290 
2291  /* fill in any unspecified alias columns */
2292  varattno = 0;
2293  foreach(lc, cte->ctecolnames)
2294  {
2295  varattno++;
2296  if (varattno > numaliases)
2297  eref->colnames = lappend(eref->colnames, lfirst(lc));
2298  }
2299  if (varattno < numaliases)
2300  ereport(ERROR,
2301  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
2302  errmsg("table \"%s\" has %d columns available but %d columns specified",
2303  refname, varattno, numaliases)));
2304 
2305  rte->eref = eref;
2306 
2307  if (cte->search_clause)
2308  {
2311  rte->coltypes = lappend_oid(rte->coltypes, RECORDOID);
2312  else
2313  rte->coltypes = lappend_oid(rte->coltypes, RECORDARRAYOID);
2314  rte->coltypmods = lappend_int(rte->coltypmods, -1);
2316 
2317  n_dontexpand_columns += 1;
2318  }
2319 
2320  if (cte->cycle_clause)
2321  {
2326 
2328  rte->coltypes = lappend_oid(rte->coltypes, RECORDARRAYOID);
2329  rte->coltypmods = lappend_int(rte->coltypmods, -1);
2331 
2332  n_dontexpand_columns += 2;
2333  }
2334 
2335  /*
2336  * Set flags and access permissions.
2337  *
2338  * Subqueries are never checked for access rights.
2339  */
2340  rte->lateral = false;
2341  rte->inh = false; /* never true for subqueries */
2342  rte->inFromCl = inFromCl;
2343 
2344  rte->requiredPerms = 0;
2345  rte->checkAsUser = InvalidOid;
2346  rte->selectedCols = NULL;
2347  rte->insertedCols = NULL;
2348  rte->updatedCols = NULL;
2349  rte->extraUpdatedCols = NULL;
2350 
2351  /*
2352  * Add completed RTE to pstate's range table list, so that we know its
2353  * index. But we don't add it to the join list --- caller must do that if
2354  * appropriate.
2355  */
2356  pstate->p_rtable = lappend(pstate->p_rtable, rte);
2357 
2358  /*
2359  * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
2360  * list --- caller must do that if appropriate.
2361  */
2362  psi = buildNSItemFromLists(rte, list_length(pstate->p_rtable),
2363  rte->coltypes, rte->coltypmods,
2364  rte->colcollations);
2365 
2366  /*
2367  * The columns added by search and cycle clauses are not included in star
2368  * expansion in queries contained in the CTE.
2369  */
2370  if (rte->ctelevelsup > 0)
2371  for (int i = 0; i < n_dontexpand_columns; i++)
2372  psi->p_nscolumns[list_length(psi->p_names->colnames) - 1 - i].p_dontexpand = true;
2373 
2374  return psi;
2375 }
2376 
2377 /*
2378  * Add an entry for an ephemeral named relation reference to the pstate's
2379  * range table (p_rtable).
2380  * Then, construct and return a ParseNamespaceItem for the new RTE.
2381  *
2382  * It is expected that the RangeVar, which up until now is only known to be an
2383  * ephemeral named relation, will (in conjunction with the QueryEnvironment in
2384  * the ParseState), create a RangeTblEntry for a specific *kind* of ephemeral
2385  * named relation, based on enrtype.
2386  *
2387  * This is much like addRangeTableEntry() except that it makes an RTE for an
2388  * ephemeral named relation.
2389  */
2392  RangeVar *rv,
2393  bool inFromCl)
2394 {
2396  Alias *alias = rv->alias;
2397  char *refname = alias ? alias->aliasname : rv->relname;
2399  TupleDesc tupdesc;
2400  int attno;
2401 
2402  Assert(pstate != NULL);
2403  enrmd = get_visible_ENR(pstate, rv->relname);
2404  Assert(enrmd != NULL);
2405 
2406  switch (enrmd->enrtype)
2407  {
2408  case ENR_NAMED_TUPLESTORE:
2410  break;
2411 
2412  default:
2413  elog(ERROR, "unexpected enrtype: %d", enrmd->enrtype);
2414  return NULL; /* for fussy compilers */
2415  }
2416 
2417  /*
2418  * Record dependency on a relation. This allows plans to be invalidated
2419  * if they access transition tables linked to a table that is altered.
2420  */
2421  rte->relid = enrmd->reliddesc;
2422 
2423  /*
2424  * Build the list of effective column names using user-supplied aliases
2425  * and/or actual column names.
2426  */
2427  tupdesc = ENRMetadataGetTupDesc(enrmd);
2428  rte->eref = makeAlias(refname, NIL);
2429  buildRelationAliases(tupdesc, alias, rte->eref);
2430 
2431  /* Record additional data for ENR, including column type info */
2432  rte->enrname = enrmd->name;
2433  rte->enrtuples = enrmd->enrtuples;
2434  rte->coltypes = NIL;
2435  rte->coltypmods = NIL;
2436  rte->colcollations = NIL;
2437  for (attno = 1; attno <= tupdesc->natts; ++attno)
2438  {
2439  Form_pg_attribute att = TupleDescAttr(tupdesc, attno - 1);
2440 
2441  if (att->attisdropped)
2442  {
2443  /* Record zeroes for a dropped column */
2444  rte->coltypes = lappend_oid(rte->coltypes, InvalidOid);
2445  rte->coltypmods = lappend_int(rte->coltypmods, 0);
2447  }
2448  else
2449  {
2450  /* Let's just make sure we can tell this isn't dropped */
2451  if (att->atttypid == InvalidOid)
2452  elog(ERROR, "atttypid is invalid for non-dropped column in \"%s\"",
2453  rv->relname);
2454  rte->coltypes = lappend_oid(rte->coltypes, att->atttypid);
2455  rte->coltypmods = lappend_int(rte->coltypmods, att->atttypmod);
2457  att->attcollation);
2458  }
2459  }
2460 
2461  /*
2462  * Set flags and access permissions.
2463  *
2464  * ENRs are never checked for access rights.
2465  */
2466  rte->lateral = false;
2467  rte->inh = false; /* never true for ENRs */
2468  rte->inFromCl = inFromCl;
2469 
2470  rte->requiredPerms = 0;
2471  rte->checkAsUser = InvalidOid;
2472  rte->selectedCols = NULL;
2473 
2474  /*
2475  * Add completed RTE to pstate's range table list, so that we know its
2476  * index. But we don't add it to the join list --- caller must do that if
2477  * appropriate.
2478  */
2479  pstate->p_rtable = lappend(pstate->p_rtable, rte);
2480 
2481  /*
2482  * Build a ParseNamespaceItem, but don't add it to the pstate's namespace
2483  * list --- caller must do that if appropriate.
2484  */
2485  return buildNSItemFromTupleDesc(rte, list_length(pstate->p_rtable),
2486  tupdesc);
2487 }
2488 
2489 
2490 /*
2491  * Has the specified refname been selected FOR UPDATE/FOR SHARE?
2492  *
2493  * This is used when we have not yet done transformLockingClause, but need
2494  * to know the correct lock to take during initial opening of relations.
2495  *
2496  * Note: we pay no attention to whether it's FOR UPDATE vs FOR SHARE,
2497  * since the table-level lock is the same either way.
2498  */
2499 bool
2500 isLockedRefname(ParseState *pstate, const char *refname)
2501 {
2502  ListCell *l;
2503 
2504  /*
2505  * If we are in a subquery specified as locked FOR UPDATE/SHARE from
2506  * parent level, then act as though there's a generic FOR UPDATE here.
2507  */
2508  if (pstate->p_locked_from_parent)
2509  return true;
2510 
2511  foreach(l, pstate->p_locking_clause)
2512  {
2513  LockingClause *lc = (LockingClause *) lfirst(l);
2514 
2515  if (lc->lockedRels == NIL)
2516  {
2517  /* all tables used in query */
2518  return true;
2519  }
2520  else
2521  {
2522  /* just the named tables */
2523  ListCell *l2;
2524 
2525  foreach(l2, lc->lockedRels)
2526  {
2527  RangeVar *thisrel = (RangeVar *) lfirst(l2);
2528 
2529  if (strcmp(refname, thisrel->relname) == 0)
2530  return true;
2531  }
2532  }
2533  }
2534  return false;
2535 }
2536 
2537 /*
2538  * Add the given nsitem/RTE as a top-level entry in the pstate's join list
2539  * and/or namespace list. (We assume caller has checked for any
2540  * namespace conflicts.) The nsitem is always marked as unconditionally
2541  * visible, that is, not LATERAL-only.
2542  */
2543 void
2545  bool addToJoinList,
2546  bool addToRelNameSpace, bool addToVarNameSpace)
2547 {
2548  if (addToJoinList)
2549  {
2551 
2552  rtr->rtindex = nsitem->p_rtindex;
2553  pstate->p_joinlist = lappend(pstate->p_joinlist, rtr);
2554  }
2555  if (addToRelNameSpace || addToVarNameSpace)
2556  {
2557  /* Set the new nsitem's visibility flags correctly */
2558  nsitem->p_rel_visible = addToRelNameSpace;
2559  nsitem->p_cols_visible = addToVarNameSpace;
2560  nsitem->p_lateral_only = false;
2561  nsitem->p_lateral_ok = true;
2562  pstate->p_namespace = lappend(pstate->p_namespace, nsitem);
2563  }
2564 }
2565 
2566 /*
2567  * expandRTE -- expand the columns of a rangetable entry
2568  *
2569  * This creates lists of an RTE's column names (aliases if provided, else
2570  * real names) and Vars for each column. Only user columns are considered.
2571  * If include_dropped is false then dropped columns are omitted from the
2572  * results. If include_dropped is true then empty strings and NULL constants
2573  * (not Vars!) are returned for dropped columns.
2574  *
2575  * rtindex, sublevels_up, and location are the varno, varlevelsup, and location
2576  * values to use in the created Vars. Ordinarily rtindex should match the
2577  * actual position of the RTE in its rangetable.
2578  *
2579  * The output lists go into *colnames and *colvars.
2580  * If only one of the two kinds of output list is needed, pass NULL for the
2581  * output pointer for the unwanted one.
2582  */
2583 void
2584 expandRTE(RangeTblEntry *rte, int rtindex, int sublevels_up,
2585  int location, bool include_dropped,
2586  List **colnames, List **colvars)
2587 {
2588  int varattno;
2589 
2590  if (colnames)
2591  *colnames = NIL;
2592  if (colvars)
2593  *colvars = NIL;
2594 
2595  switch (rte->rtekind)
2596  {
2597  case RTE_RELATION:
2598  /* Ordinary relation RTE */
2599  expandRelation(rte->relid, rte->eref,
2600  rtindex, sublevels_up, location,
2601  include_dropped, colnames, colvars);
2602  break;
2603  case RTE_SUBQUERY:
2604  {
2605  /* Subquery RTE */
2606  ListCell *aliasp_item = list_head(rte->eref->colnames);
2607  ListCell *tlistitem;
2608 
2609  varattno = 0;
2610  foreach(tlistitem, rte->subquery->targetList)
2611  {
2612  TargetEntry *te = (TargetEntry *) lfirst(tlistitem);
2613 
2614  if (te->resjunk)
2615  continue;
2616  varattno++;
2617  Assert(varattno == te->resno);
2618 
2619  /*
2620  * In scenarios where columns have been added to a view
2621  * since the outer query was originally parsed, there can
2622  * be more items in the subquery tlist than the outer
2623  * query expects. We should ignore such extra column(s)
2624  * --- compare the behavior for composite-returning
2625  * functions, in the RTE_FUNCTION case below.
2626  */
2627  if (!aliasp_item)
2628  break;
2629 
2630  if (colnames)
2631  {
2632  char *label = strVal(lfirst(aliasp_item));
2633 
2634  *colnames = lappend(*colnames, makeString(pstrdup(label)));
2635  }
2636 
2637  if (colvars)
2638  {
2639  Var *varnode;
2640 
2641  varnode = makeVar(rtindex, varattno,
2642  exprType((Node *) te->expr),
2643  exprTypmod((Node *) te->expr),
2644  exprCollation((Node *) te->expr),
2645  sublevels_up);
2646  varnode->location = location;
2647 
2648  *colvars = lappend(*colvars, varnode);
2649  }
2650 
2651  aliasp_item = lnext(rte->eref->colnames, aliasp_item);
2652  }
2653  }
2654  break;
2655  case RTE_FUNCTION:
2656  {
2657  /* Function RTE */
2658  int atts_done = 0;
2659  ListCell *lc;
2660 
2661  foreach(lc, rte->functions)
2662  {
2663  RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc);
2664  TypeFuncClass functypclass;
2665  Oid funcrettype;
2666  TupleDesc tupdesc;
2667 
2668  functypclass = get_expr_result_type(rtfunc->funcexpr,
2669  &funcrettype,
2670  &tupdesc);
2671  if (functypclass == TYPEFUNC_COMPOSITE ||
2672  functypclass == TYPEFUNC_COMPOSITE_DOMAIN)
2673  {
2674  /* Composite data type, e.g. a table's row type */
2675  Assert(tupdesc);
2676  expandTupleDesc(tupdesc, rte->eref,
2677  rtfunc->funccolcount, atts_done,
2678  rtindex, sublevels_up, location,
2679  include_dropped, colnames, colvars);
2680  }
2681  else if (functypclass == TYPEFUNC_SCALAR)
2682  {
2683  /* Base data type, i.e. scalar */
2684  if (colnames)
2685  *colnames = lappend(*colnames,
2686  list_nth(rte->eref->colnames,
2687  atts_done));
2688 
2689  if (colvars)
2690  {
2691  Var *varnode;
2692 
2693  varnode = makeVar(rtindex, atts_done + 1,
2694  funcrettype,
2695  exprTypmod(rtfunc->funcexpr),
2696  exprCollation(rtfunc->funcexpr),
2697  sublevels_up);
2698  varnode->location = location;
2699 
2700  *colvars = lappend(*colvars, varnode);
2701  }
2702  }
2703  else if (functypclass == TYPEFUNC_RECORD)
2704  {
2705  if (colnames)
2706  {
2707  List *namelist;
2708 
2709  /* extract appropriate subset of column list */
2710  namelist = list_copy_tail(rte->eref->colnames,
2711  atts_done);
2712  namelist = list_truncate(namelist,
2713  rtfunc->funccolcount);
2714  *colnames = list_concat(*colnames, namelist);
2715  }
2716 
2717  if (colvars)
2718  {
2719  ListCell *l1;
2720  ListCell *l2;
2721  ListCell *l3;
2722  int attnum = atts_done;
2723 
2724  forthree(l1, rtfunc->funccoltypes,
2725  l2, rtfunc->funccoltypmods,
2726  l3, rtfunc->funccolcollations)
2727  {
2728  Oid attrtype = lfirst_oid(l1);
2729  int32 attrtypmod = lfirst_int(l2);
2730  Oid attrcollation = lfirst_oid(l3);
2731  Var *varnode;
2732 
2733  attnum++;
2734  varnode = makeVar(rtindex,
2735  attnum,
2736  attrtype,
2737  attrtypmod,
2738  attrcollation,
2739  sublevels_up);
2740  varnode->location = location;
2741  *colvars = lappend(*colvars, varnode);
2742  }
2743  }
2744  }
2745  else
2746  {
2747  /* addRangeTableEntryForFunction should've caught this */
2748  elog(ERROR, "function in FROM has unsupported return type");
2749  }
2750  atts_done += rtfunc->funccolcount;
2751  }
2752 
2753  /* Append the ordinality column if any */
2754  if (rte->funcordinality)
2755  {
2756  if (colnames)
2757  *colnames = lappend(*colnames,
2758  llast(rte->eref->colnames));
2759 
2760  if (colvars)
2761  {
2762  Var *varnode = makeVar(rtindex,
2763  atts_done + 1,
2764  INT8OID,
2765  -1,
2766  InvalidOid,
2767  sublevels_up);
2768 
2769  *colvars = lappend(*colvars, varnode);
2770  }
2771  }
2772  }
2773  break;
2774  case RTE_JOIN:
2775  {
2776  /* Join RTE */
2777  ListCell *colname;
2778  ListCell *aliasvar;
2779 
2781 
2782  varattno = 0;
2783  forboth(colname, rte->eref->colnames, aliasvar, rte->joinaliasvars)
2784  {
2785  Node *avar = (Node *) lfirst(aliasvar);
2786 
2787  varattno++;
2788 
2789  /*
2790  * During ordinary parsing, there will never be any
2791  * deleted columns in the join. While this function is
2792  * also used by the rewriter and planner, they do not
2793  * currently call it on any JOIN RTEs. Therefore, this
2794  * next bit is dead code, but it seems prudent to handle
2795  * the case correctly anyway.
2796  */
2797  if (avar == NULL)
2798  {
2799  if (include_dropped)
2800  {
2801  if (colnames)
2802  *colnames = lappend(*colnames,
2803  makeString(pstrdup("")));
2804  if (colvars)
2805  {
2806  /*
2807  * Can't use join's column type here (it might
2808  * be dropped!); but it doesn't really matter
2809  * what type the Const claims to be.
2810  */
2811  *colvars = lappend(*colvars,
2812  makeNullConst(INT4OID, -1,
2813  InvalidOid));
2814  }
2815  }
2816  continue;
2817  }
2818 
2819  if (colnames)
2820  {
2821  char *label = strVal(lfirst(colname));
2822 
2823  *colnames = lappend(*colnames,
2824  makeString(pstrdup(label)));
2825  }
2826 
2827  if (colvars)
2828  {
2829  Var *varnode;
2830 
2831  /*
2832  * If the joinaliasvars entry is a simple Var, just
2833  * copy it (with adjustment of varlevelsup and
2834  * location); otherwise it is a JOIN USING column and
2835  * we must generate a join alias Var. This matches
2836  * the results that expansion of "join.*" by
2837  * expandNSItemVars would have produced, if we had
2838  * access to the ParseNamespaceItem for the join.
2839  */
2840  if (IsA(avar, Var))
2841  {
2842  varnode = copyObject((Var *) avar);
2843  varnode->varlevelsup = sublevels_up;
2844  }
2845  else
2846  varnode = makeVar(rtindex, varattno,
2847  exprType(avar),
2848  exprTypmod(avar),
2849  exprCollation(avar),
2850  sublevels_up);
2851  varnode->location = location;
2852 
2853  *colvars = lappend(*colvars, varnode);
2854  }
2855  }
2856  }
2857  break;
2858  case RTE_TABLEFUNC:
2859  case RTE_VALUES:
2860  case RTE_CTE:
2861  case RTE_NAMEDTUPLESTORE:
2862  {
2863  /* Tablefunc, Values, CTE, or ENR RTE */
2864  ListCell *aliasp_item = list_head(rte->eref->colnames);
2865  ListCell *lct;
2866  ListCell *lcm;
2867  ListCell *lcc;
2868 
2869  varattno = 0;
2870  forthree(lct, rte->coltypes,
2871  lcm, rte->coltypmods,
2872  lcc, rte->colcollations)
2873  {
2874  Oid coltype = lfirst_oid(lct);
2875  int32 coltypmod = lfirst_int(lcm);
2876  Oid colcoll = lfirst_oid(lcc);
2877 
2878  varattno++;
2879 
2880  if (colnames)
2881  {
2882  /* Assume there is one alias per output column */
2883  if (OidIsValid(coltype))
2884  {
2885  char *label = strVal(lfirst(aliasp_item));
2886 
2887  *colnames = lappend(*colnames,
2888  makeString(pstrdup(label)));
2889  }
2890  else if (include_dropped)
2891  *colnames = lappend(*colnames,
2892  makeString(pstrdup("")));
2893 
2894  aliasp_item = lnext(rte->eref->colnames, aliasp_item);
2895  }
2896 
2897  if (colvars)
2898  {
2899  if (OidIsValid(coltype))
2900  {
2901  Var *varnode;
2902 
2903  varnode = makeVar(rtindex, varattno,
2904  coltype, coltypmod, colcoll,
2905  sublevels_up);
2906  varnode->location = location;
2907 
2908  *colvars = lappend(*colvars, varnode);
2909  }
2910  else if (include_dropped)
2911  {
2912  /*
2913  * It doesn't really matter what type the Const
2914  * claims to be.
2915  */
2916  *colvars = lappend(*colvars,
2917  makeNullConst(INT4OID, -1,
2918  InvalidOid));
2919  }
2920  }
2921  }
2922  }
2923  break;
2924  case RTE_RESULT:
2925  /* These expose no columns, so nothing to do */
2926  break;
2927  default:
2928  elog(ERROR, "unrecognized RTE kind: %d", (int) rte->rtekind);
2929  }
2930 }
2931 
2932 /*
2933  * expandRelation -- expandRTE subroutine
2934  */
2935 static void
2936 expandRelation(Oid relid, Alias *eref, int rtindex, int sublevels_up,
2937  int location, bool include_dropped,
2938  List **colnames, List **colvars)
2939 {
2940  Relation rel;
2941 
2942  /* Get the tupledesc and turn it over to expandTupleDesc */
2943  rel = relation_open(relid, AccessShareLock);
2944  expandTupleDesc(rel->rd_att, eref, rel->rd_att->natts, 0,
2945  rtindex, sublevels_up,
2946  location, include_dropped,
2947  colnames, colvars);
2949 }
2950 
2951 /*
2952  * expandTupleDesc -- expandRTE subroutine
2953  *
2954  * Generate names and/or Vars for the first "count" attributes of the tupdesc,
2955  * and append them to colnames/colvars. "offset" is added to the varattno
2956  * that each Var would otherwise have, and we also skip the first "offset"
2957  * entries in eref->colnames. (These provisions allow use of this code for
2958  * an individual composite-returning function in an RTE_FUNCTION RTE.)
2959  */
2960 static void
2961 expandTupleDesc(TupleDesc tupdesc, Alias *eref, int count, int offset,
2962  int rtindex, int sublevels_up,
2963  int location, bool include_dropped,
2964  List **colnames, List **colvars)
2965 {
2966  ListCell *aliascell;
2967  int varattno;
2968 
2969  aliascell = (offset < list_length(eref->colnames)) ?
2970  list_nth_cell(eref->colnames, offset) : NULL;
2971 
2972  Assert(count <= tupdesc->natts);
2973  for (varattno = 0; varattno < count; varattno++)
2974  {
2975  Form_pg_attribute attr = TupleDescAttr(tupdesc, varattno);
2976 
2977  if (attr->attisdropped)
2978  {
2979  if (include_dropped)
2980  {
2981  if (colnames)
2982  *colnames = lappend(*colnames, makeString(pstrdup("")));
2983  if (colvars)
2984  {
2985  /*
2986  * can't use atttypid here, but it doesn't really matter
2987  * what type the Const claims to be.
2988  */
2989  *colvars = lappend(*colvars,
2990  makeNullConst(INT4OID, -1, InvalidOid));
2991  }
2992  }
2993  if (aliascell)
2994  aliascell = lnext(eref->colnames, aliascell);
2995  continue;
2996  }
2997 
2998  if (colnames)
2999  {
3000  char *label;
3001 
3002  if (aliascell)
3003  {
3004  label = strVal(lfirst(aliascell));
3005  aliascell = lnext(eref->colnames, aliascell);
3006  }
3007  else
3008  {
3009  /* If we run out of aliases, use the underlying name */
3010  label = NameStr(attr->attname);
3011  }
3012  *colnames = lappend(*colnames, makeString(pstrdup(label)));
3013  }
3014 
3015  if (colvars)
3016  {
3017  Var *varnode;
3018 
3019  varnode = makeVar(rtindex, varattno + offset + 1,
3020  attr->atttypid, attr->atttypmod,
3021  attr->attcollation,
3022  sublevels_up);
3023  varnode->location = location;
3024 
3025  *colvars = lappend(*colvars, varnode);
3026  }
3027  }
3028 }
3029 
3030 /*
3031  * expandNSItemVars
3032  * Produce a list of Vars, and optionally a list of column names,
3033  * for the non-dropped columns of the nsitem.
3034  *
3035  * The emitted Vars are marked with the given sublevels_up and location.
3036  *
3037  * If colnames isn't NULL, a list of String items for the columns is stored
3038  * there; note that it's just a subset of the RTE's eref list, and hence
3039  * the list elements mustn't be modified.
3040  */
3041 List *
3043  int sublevels_up, int location,
3044  List **colnames)
3045 {
3046  List *result = NIL;
3047  int colindex;
3048  ListCell *lc;
3049 
3050  if (colnames)
3051  *colnames = NIL;
3052  colindex = 0;
3053  foreach(lc, nsitem->p_names->colnames)
3054  {
3055  Value *colnameval = (Value *) lfirst(lc);
3056  const char *colname = strVal(colnameval);
3057  ParseNamespaceColumn *nscol = nsitem->p_nscolumns + colindex;
3058 
3059  if (nscol->p_dontexpand)
3060  {
3061  /* skip */
3062  }
3063  else if (colname[0])
3064  {
3065  Var *var;
3066 
3067  Assert(nscol->p_varno > 0);
3068  var = makeVar(nscol->p_varno,
3069  nscol->p_varattno,
3070  nscol->p_vartype,
3071  nscol->p_vartypmod,
3072  nscol->p_varcollid,
3073  sublevels_up);
3074  /* makeVar doesn't offer parameters for these, so set by hand: */
3075  var->varnosyn = nscol->p_varnosyn;
3076  var->varattnosyn = nscol->p_varattnosyn;
3077  var->location = location;
3078  result = lappend(result, var);
3079  if (colnames)
3080  *colnames = lappend(*colnames, colnameval);
3081  }
3082  else
3083  {
3084  /* dropped column, ignore */
3085  Assert(nscol->p_varno == 0);
3086  }
3087  colindex++;
3088  }
3089  return result;
3090 }
3091 
3092 /*
3093  * expandNSItemAttrs -
3094  * Workhorse for "*" expansion: produce a list of targetentries
3095  * for the attributes of the nsitem
3096  *
3097  * pstate->p_next_resno determines the resnos assigned to the TLEs.
3098  * The referenced columns are marked as requiring SELECT access.
3099  */
3100 List *
3102  int sublevels_up, int location)
3103 {
3104  RangeTblEntry *rte = nsitem->p_rte;
3105  List *names,
3106  *vars;
3107  ListCell *name,
3108  *var;
3109  List *te_list = NIL;
3110 
3111  vars = expandNSItemVars(nsitem, sublevels_up, location, &names);
3112 
3113  /*
3114  * Require read access to the table. This is normally redundant with the
3115  * markVarForSelectPriv calls below, but not if the table has zero
3116  * columns. We need not do anything if the nsitem is for a join: its
3117  * component tables will have been marked ACL_SELECT when they were added
3118  * to the rangetable. (This step changes things only for the target
3119  * relation of UPDATE/DELETE, which cannot be under a join.)
3120  */
3121  if (rte->rtekind == RTE_RELATION)
3122  rte->requiredPerms |= ACL_SELECT;
3123 
3124  forboth(name, names, var, vars)
3125  {
3126  char *label = strVal(lfirst(name));
3127  Var *varnode = (Var *) lfirst(var);
3128  TargetEntry *te;
3129 
3130  te = makeTargetEntry((Expr *) varnode,
3131  (AttrNumber) pstate->p_next_resno++,
3132  label,
3133  false);
3134  te_list = lappend(te_list, te);
3135 
3136  /* Require read access to each column */
3137  markVarForSelectPriv(pstate, varnode);
3138  }
3139 
3140  Assert(name == NULL && var == NULL); /* lists not the same length? */
3141 
3142  return te_list;
3143 }
3144 
3145 /*
3146  * get_rte_attribute_name
3147  * Get an attribute name from a RangeTblEntry
3148  *
3149  * This is unlike get_attname() because we use aliases if available.
3150  * In particular, it will work on an RTE for a subselect or join, whereas
3151  * get_attname() only works on real relations.
3152  *
3153  * "*" is returned if the given attnum is InvalidAttrNumber --- this case
3154  * occurs when a Var represents a whole tuple of a relation.
3155  */
3156 char *
3158 {
3159  if (attnum == InvalidAttrNumber)
3160  return "*";
3161 
3162  /*
3163  * If there is a user-written column alias, use it.
3164  */
3165  if (rte->alias &&
3166  attnum > 0 && attnum <= list_length(rte->alias->colnames))
3167  return strVal(list_nth(rte->alias->colnames, attnum - 1));
3168 
3169  /*
3170  * If the RTE is a relation, go to the system catalogs not the
3171  * eref->colnames list. This is a little slower but it will give the
3172  * right answer if the column has been renamed since the eref list was
3173  * built (which can easily happen for rules).
3174  */
3175  if (rte->rtekind == RTE_RELATION)
3176  return get_attname(rte->relid, attnum, false);
3177 
3178  /*
3179  * Otherwise use the column name from eref. There should always be one.
3180  */
3181  if (attnum > 0 && attnum <= list_length(rte->eref->colnames))
3182  return strVal(list_nth(rte->eref->colnames, attnum - 1));
3183 
3184  /* else caller gave us a bogus attnum */
3185  elog(ERROR, "invalid attnum %d for rangetable entry %s",
3186  attnum, rte->eref->aliasname);
3187  return NULL; /* keep compiler quiet */
3188 }
3189 
3190 /*
3191  * get_rte_attribute_is_dropped
3192  * Check whether attempted attribute ref is to a dropped column
3193  */
3194 bool
3196 {
3197  bool result;
3198 
3199  switch (rte->rtekind)
3200  {
3201  case RTE_RELATION:
3202  {
3203  /*
3204  * Plain relation RTE --- get the attribute's catalog entry
3205  */
3206  HeapTuple tp;
3207  Form_pg_attribute att_tup;
3208 
3209  tp = SearchSysCache2(ATTNUM,
3210  ObjectIdGetDatum(rte->relid),
3211  Int16GetDatum(attnum));
3212  if (!HeapTupleIsValid(tp)) /* shouldn't happen */
3213  elog(ERROR, "cache lookup failed for attribute %d of relation %u",
3214  attnum, rte->relid);
3215  att_tup = (Form_pg_attribute) GETSTRUCT(tp);
3216  result = att_tup->attisdropped;
3217  ReleaseSysCache(tp);
3218  }
3219  break;
3220  case RTE_SUBQUERY:
3221  case RTE_TABLEFUNC:
3222  case RTE_VALUES:
3223  case RTE_CTE:
3224 
3225  /*
3226  * Subselect, Table Functions, Values, CTE RTEs never have dropped
3227  * columns
3228  */
3229  result = false;
3230  break;
3231  case RTE_NAMEDTUPLESTORE:
3232  {
3233  /* Check dropped-ness by testing for valid coltype */
3234  if (attnum <= 0 ||
3235  attnum > list_length(rte->coltypes))
3236  elog(ERROR, "invalid varattno %d", attnum);
3237  result = !OidIsValid((list_nth_oid(rte->coltypes, attnum - 1)));
3238  }
3239  break;
3240  case RTE_JOIN:
3241  {
3242  /*
3243  * A join RTE would not have dropped columns when constructed,
3244  * but one in a stored rule might contain columns that were
3245  * dropped from the underlying tables, if said columns are
3246  * nowhere explicitly referenced in the rule. This will be
3247  * signaled to us by a null pointer in the joinaliasvars list.
3248  */
3249  Var *aliasvar;
3250 
3251  if (attnum <= 0 ||
3252  attnum > list_length(rte->joinaliasvars))
3253  elog(ERROR, "invalid varattno %d", attnum);
3254  aliasvar = (Var *) list_nth(rte->joinaliasvars, attnum - 1);
3255 
3256  result = (aliasvar == NULL);
3257  }
3258  break;
3259  case RTE_FUNCTION:
3260  {
3261  /* Function RTE */
3262  ListCell *lc;
3263  int atts_done = 0;
3264 
3265  /*
3266  * Dropped attributes are only possible with functions that
3267  * return named composite types. In such a case we have to
3268  * look up the result type to see if it currently has this
3269  * column dropped. So first, loop over the funcs until we
3270  * find the one that covers the requested column.
3271  */
3272  foreach(lc, rte->functions)
3273  {
3274  RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc);
3275 
3276  if (attnum > atts_done &&
3277  attnum <= atts_done + rtfunc->funccolcount)
3278  {
3279  TupleDesc tupdesc;
3280 
3281  tupdesc = get_expr_result_tupdesc(rtfunc->funcexpr,
3282  true);
3283  if (tupdesc)
3284  {
3285  /* Composite data type, e.g. a table's row type */
3286  Form_pg_attribute att_tup;
3287 
3288  Assert(tupdesc);
3289  Assert(attnum - atts_done <= tupdesc->natts);
3290  att_tup = TupleDescAttr(tupdesc,
3291  attnum - atts_done - 1);
3292  return att_tup->attisdropped;
3293  }
3294  /* Otherwise, it can't have any dropped columns */
3295  return false;
3296  }
3297  atts_done += rtfunc->funccolcount;
3298  }
3299 
3300  /* If we get here, must be looking for the ordinality column */
3301  if (rte->funcordinality && attnum == atts_done + 1)
3302  return false;
3303 
3304  /* this probably can't happen ... */
3305  ereport(ERROR,
3306  (errcode(ERRCODE_UNDEFINED_COLUMN),
3307  errmsg("column %d of relation \"%s\" does not exist",
3308  attnum,
3309  rte->eref->aliasname)));
3310  result = false; /* keep compiler quiet */
3311  }
3312  break;
3313  case RTE_RESULT:
3314  /* this probably can't happen ... */
3315  ereport(ERROR,
3316  (errcode(ERRCODE_UNDEFINED_COLUMN),
3317  errmsg("column %d of relation \"%s\" does not exist",
3318  attnum,
3319  rte->eref->aliasname)));
3320  result = false; /* keep compiler quiet */
3321  break;
3322  default:
3323  elog(ERROR, "unrecognized RTE kind: %d", (int) rte->rtekind);
3324  result = false; /* keep compiler quiet */
3325  }
3326 
3327  return result;
3328 }
3329 
3330 /*
3331  * Given a targetlist and a resno, return the matching TargetEntry
3332  *
3333  * Returns NULL if resno is not present in list.
3334  *
3335  * Note: we need to search, rather than just indexing with list_nth(),
3336  * because not all tlists are sorted by resno.
3337  */
3338 TargetEntry *
3340 {
3341  ListCell *l;
3342 
3343  foreach(l, tlist)
3344  {
3345  TargetEntry *tle = (TargetEntry *) lfirst(l);
3346 
3347  if (tle->resno == resno)
3348  return tle;
3349  }
3350  return NULL;
3351 }
3352 
3353 /*
3354  * Given a Query and rangetable index, return relation's RowMarkClause if any
3355  *
3356  * Returns NULL if relation is not selected FOR UPDATE/SHARE
3357  */
3358 RowMarkClause *
3360 {
3361  ListCell *l;
3362 
3363  foreach(l, qry->rowMarks)
3364  {
3365  RowMarkClause *rc = (RowMarkClause *) lfirst(l);
3366 
3367  if (rc->rti == rtindex)
3368  return rc;
3369  }
3370  return NULL;
3371 }
3372 
3373 /*
3374  * given relation and att name, return attnum of variable
3375  *
3376  * Returns InvalidAttrNumber if the attr doesn't exist (or is dropped).
3377  *
3378  * This should only be used if the relation is already
3379  * table_open()'ed. Use the cache version get_attnum()
3380  * for access to non-opened relations.
3381  */
3382 int
3383 attnameAttNum(Relation rd, const char *attname, bool sysColOK)
3384 {
3385  int i;
3386 
3387  for (i = 0; i < RelationGetNumberOfAttributes(rd); i++)
3388  {
3389  Form_pg_attribute att = TupleDescAttr(rd->rd_att, i);
3390 
3391  if (namestrcmp(&(att->attname), attname) == 0 && !att->attisdropped)
3392  return i + 1;
3393  }
3394 
3395  if (sysColOK)
3396  {
3397  if ((i = specialAttNum(attname)) != InvalidAttrNumber)
3398  return i;
3399  }
3400 
3401  /* on failure */
3402  return InvalidAttrNumber;
3403 }
3404 
3405 /* specialAttNum()
3406  *
3407  * Check attribute name to see if it is "special", e.g. "xmin".
3408  * - thomas 2000-02-07
3409  *
3410  * Note: this only discovers whether the name could be a system attribute.
3411  * Caller needs to ensure that it really is an attribute of the rel.
3412  */
3413 static int
3415 {
3416  const FormData_pg_attribute *sysatt;
3417 
3418  sysatt = SystemAttributeByName(attname);
3419  if (sysatt != NULL)
3420  return sysatt->attnum;
3421  return InvalidAttrNumber;
3422 }
3423 
3424 
3425 /*
3426  * given attribute id, return name of that attribute
3427  *
3428  * This should only be used if the relation is already
3429  * table_open()'ed. Use the cache version get_atttype()
3430  * for access to non-opened relations.
3431  */
3432 const NameData *
3433 attnumAttName(Relation rd, int attid)
3434 {
3435  if (attid <= 0)
3436  {
3437  const FormData_pg_attribute *sysatt;
3438 
3439  sysatt = SystemAttributeDefinition(attid);
3440  return &sysatt->attname;
3441  }
3442  if (attid > rd->rd_att->natts)
3443  elog(ERROR, "invalid attribute number %d", attid);
3444  return &TupleDescAttr(rd->rd_att, attid - 1)->attname;
3445 }
3446 
3447 /*
3448  * given attribute id, return type of that attribute
3449  *
3450  * This should only be used if the relation is already
3451  * table_open()'ed. Use the cache version get_atttype()
3452  * for access to non-opened relations.
3453  */
3454 Oid
3455 attnumTypeId(Relation rd, int attid)
3456 {
3457  if (attid <= 0)
3458  {
3459  const FormData_pg_attribute *sysatt;
3460 
3461  sysatt = SystemAttributeDefinition(attid);
3462  return sysatt->atttypid;
3463  }
3464  if (attid > rd->rd_att->natts)
3465  elog(ERROR, "invalid attribute number %d", attid);
3466  return TupleDescAttr(rd->rd_att, attid - 1)->atttypid;
3467 }
3468 
3469 /*
3470  * given attribute id, return collation of that attribute
3471  *
3472  * This should only be used if the relation is already table_open()'ed.
3473  */
3474 Oid
3476 {
3477  if (attid <= 0)
3478  {
3479  /* All system attributes are of noncollatable types. */
3480  return InvalidOid;
3481  }
3482  if (attid > rd->rd_att->natts)
3483  elog(ERROR, "invalid attribute number %d", attid);
3484  return TupleDescAttr(rd->rd_att, attid - 1)->attcollation;
3485 }
3486 
3487 /*
3488  * Generate a suitable error about a missing RTE.
3489  *
3490  * Since this is a very common type of error, we work rather hard to
3491  * produce a helpful message.
3492  */
3493 void
3495 {
3496  RangeTblEntry *rte;
3497  const char *badAlias = NULL;
3498 
3499  /*
3500  * Check to see if there are any potential matches in the query's
3501  * rangetable. (Note: cases involving a bad schema name in the RangeVar
3502  * will throw error immediately here. That seems OK.)
3503  */
3504  rte = searchRangeTableForRel(pstate, relation);
3505 
3506  /*
3507  * If we found a match that has an alias and the alias is visible in the
3508  * namespace, then the problem is probably use of the relation's real name
3509  * instead of its alias, ie "SELECT foo.* FROM foo f". This mistake is
3510  * common enough to justify a specific hint.
3511  *
3512  * If we found a match that doesn't meet those criteria, assume the
3513  * problem is illegal use of a relation outside its scope, as in the
3514  * MySQL-ism "SELECT ... FROM a, b LEFT JOIN c ON (a.x = c.y)".
3515  */
3516  if (rte && rte->alias &&
3517  strcmp(rte->eref->aliasname, relation->relname) != 0)
3518  {
3519  ParseNamespaceItem *nsitem;
3520  int sublevels_up;
3521 
3522  nsitem = refnameNamespaceItem(pstate, NULL, rte->eref->aliasname,
3523  relation->location,
3524  &sublevels_up);
3525  if (nsitem && nsitem->p_rte == rte)
3526  badAlias = rte->eref->aliasname;
3527  }
3528 
3529  if (rte)
3530  ereport(ERROR,
3532  errmsg("invalid reference to FROM-clause entry for table \"%s\"",
3533  relation->relname),
3534  (badAlias ?
3535  errhint("Perhaps you meant to reference the table alias \"%s\".",
3536  badAlias) :
3537  errhint("There is an entry for table \"%s\", but it cannot be referenced from this part of the query.",
3538  rte->eref->aliasname)),
3539  parser_errposition(pstate, relation->location)));
3540  else
3541  ereport(ERROR,
3543  errmsg("missing FROM-clause entry for table \"%s\"",
3544  relation->relname),
3545  parser_errposition(pstate, relation->location)));
3546 }
3547 
3548 /*
3549  * Generate a suitable error about a missing column.
3550  *
3551  * Since this is a very common type of error, we work rather hard to
3552  * produce a helpful message.
3553  */
3554 void
3556  const char *relname, const char *colname, int location)
3557 {
3559  char *closestfirst = NULL;
3560 
3561  /*
3562  * Search the entire rtable looking for possible matches. If we find one,
3563  * emit a hint about it.
3564  *
3565  * TODO: improve this code (and also errorMissingRTE) to mention using
3566  * LATERAL if appropriate.
3567  */
3568  state = searchRangeTableForCol(pstate, relname, colname, location);
3569 
3570  /*
3571  * Extract closest col string for best match, if any.
3572  *
3573  * Infer an exact match referenced despite not being visible from the fact
3574  * that an attribute number was not present in state passed back -- this
3575  * is what is reported when !closestfirst. There might also be an exact
3576  * match that was qualified with an incorrect alias, in which case
3577  * closestfirst will be set (so hint is the same as generic fuzzy case).
3578  */
3579  if (state->rfirst && AttributeNumberIsValid(state->first))
3580  closestfirst = strVal(list_nth(state->rfirst->eref->colnames,
3581  state->first - 1));
3582 
3583  if (!state->rsecond)
3584  {
3585  /*
3586  * Handle case where there is zero or one column suggestions to hint,
3587  * including exact matches referenced but not visible.
3588  */
3589  ereport(ERROR,
3590  (errcode(ERRCODE_UNDEFINED_COLUMN),
3591  relname ?
3592  errmsg("column %s.%s does not exist", relname, colname) :
3593  errmsg("column \"%s\" does not exist", colname),
3594  state->rfirst ? closestfirst ?
3595  errhint("Perhaps you meant to reference the column \"%s.%s\".",
3596  state->rfirst->eref->aliasname, closestfirst) :
3597  errhint("There is a column named \"%s\" in table \"%s\", but it cannot be referenced from this part of the query.",
3598  colname, state->rfirst->eref->aliasname) : 0,
3599  parser_errposition(pstate, location)));
3600  }
3601  else
3602  {
3603  /* Handle case where there are two equally useful column hints */
3604  char *closestsecond;
3605 
3606  closestsecond = strVal(list_nth(state->rsecond->eref->colnames,
3607  state->second - 1));
3608 
3609  ereport(ERROR,
3610  (errcode(ERRCODE_UNDEFINED_COLUMN),
3611  relname ?
3612  errmsg("column %s.%s does not exist", relname, colname) :
3613  errmsg("column \"%s\" does not exist", colname),
3614  errhint("Perhaps you meant to reference the column \"%s.%s\" or the column \"%s.%s\".",
3615  state->rfirst->eref->aliasname, closestfirst,
3616  state->rsecond->eref->aliasname, closestsecond),
3617  parser_errposition(pstate, location)));
3618  }
3619 }
3620 
3621 
3622 /*
3623  * Examine a fully-parsed query, and return true iff any relation underlying
3624  * the query is a temporary relation (table, view, or materialized view).
3625  */
3626 bool
3628 {
3629  return isQueryUsingTempRelation_walker((Node *) query, NULL);
3630 }
3631 
3632 static bool
3634 {
3635  if (node == NULL)
3636  return false;
3637 
3638  if (IsA(node, Query))
3639  {
3640  Query *query = (Query *) node;
3641  ListCell *rtable;
3642 
3643  foreach(rtable, query->rtable)
3644  {
3645  RangeTblEntry *rte = lfirst(rtable);
3646 
3647  if (rte->rtekind == RTE_RELATION)
3648  {
3650  char relpersistence = rel->rd_rel->relpersistence;
3651 
3653  if (relpersistence == RELPERSISTENCE_TEMP)
3654  return true;
3655  }
3656  }
3657 
3658  return query_tree_walker(query,
3660  context,
3662  }
3663 
3664  return expression_tree_walker(node,
3666  context);
3667 }
Value * makeString(char *str)
Definition: value.c:53
List * lockedRels
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#define NIL
Definition: pg_list.h:65
bool query_tree_walker(Query *query, bool(*walker)(), void *context, int flags)
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static bool isQueryUsingTempRelation_walker(Node *node, void *context)
ParseNamespaceItem * addRangeTableEntryForCTE(ParseState *pstate, CommonTableExpr *cte, Index levelsup, RangeVar *rv, bool inFromCl)
bool search_breadth_first
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List * joinaliasvars
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Index varlevelsup
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int errhint(const char *fmt,...)
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RowMarkClause * get_parse_rowmark(Query *qry, Index rtindex)
ParseNamespaceItem * addRangeTableEntryForValues(ParseState *pstate, List *exprs, List *coltypes, List *coltypmods, List *colcollations, Alias *alias, bool lateral, bool inFromCl)
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static ListCell * lnext(const List *l, const ListCell *c)
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TupleDesc CreateTemplateTupleDesc(int natts)
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Relation table_openrv_extended(const RangeVar *relation, LOCKMODE lockmode, bool missing_ok)
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static char * label
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Definition: parse_node.h:188
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Definition: parsenodes.h:120
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Definition: parsenodes.h:1180
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Definition: nodes.h:587
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Definition: primnodes.h:1533
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Definition: htup.h:78
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Definition: relation.c:206
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Definition: c.h:804
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Definition: pg_list.h:169
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Definition: primnodes.h:42
Definition: regguts.h:317
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Definition: parsenodes.h:1089
Definition: value.h:42
List * expandNSItemVars(ParseNamespaceItem *nsitem, int sublevels_up, int location, List **colnames)
Expr * expr
Definition: primnodes.h:1444
RangeTblEntry * rsecond
Oid exprType(const Node *expr)
Definition: nodeFuncs.c:41
bool expression_tree_walker(Node *node, bool(*walker)(), void *context)
Definition: nodeFuncs.c:1904
static int list_length(const List *l)
Definition: pg_list.h:149
int parser_errposition(ParseState *pstate, int location)
Definition: parse_node.c:111
Oid exprCollation(const Node *expr)
Definition: nodeFuncs.c:759
HeapTuple SearchSysCache2(int cacheId, Datum key1, Datum key2)
Definition: syscache.c:1138
Index ctelevelsup
Definition: parsenodes.h:1106
TypeName * typeName
Definition: parsenodes.h:659
Bitmapset * funcparams
Definition: parsenodes.h:1182
#define SearchSysCacheExists2(cacheId, key1, key2)
Definition: syscache.h:186
Bitmapset * bms_add_member(Bitmapset *a, int x)
Definition: bitmapset.c:736
bool CheckRelationLockedByMe(Relation relation, LOCKMODE lockmode, bool orstronger)
Definition: lmgr.c:303
TupleDesc ENRMetadataGetTupDesc(EphemeralNamedRelationMetadata enrmd)
const char * name
Definition: encode.c:515
#define InvalidAttrNumber
Definition: attnum.h:23
#define nodeTag(nodeptr)
Definition: nodes.h:544
static void expandTupleDesc(TupleDesc tupdesc, Alias *eref, int count, int offset, int rtindex, int sublevels_up, int location, bool include_dropped, List **colnames, List **colvars)
List * ctecoltypes
Definition: parsenodes.h:1513
RTEKind rtekind
Definition: parsenodes.h:995
ParseNamespaceItem * addRangeTableEntry(ParseState *pstate, RangeVar *relation, Alias *alias, bool inh, bool inFromCl)
#define CHKATYPE_ANYRECORD
Definition: heap.h:24
char * cycle_path_column
Definition: parsenodes.h:1488
int varstr_levenshtein_less_equal(const char *source, int slen, const char *target, int tlen, int ins_c, int del_c, int sub_c, int max_d, bool trusted)
char * ctename
Definition: parsenodes.h:1105
CTECycleClause * cycle_clause
Definition: parsenodes.h:1506
ParseNamespaceItem * GetNSItemByRangeTablePosn(ParseState *pstate, int varno, int sublevels_up)
ParseNamespaceColumn * p_nscolumns
Definition: parse_node.h:271
Query * subquery
Definition: parsenodes.h:1030
double enrtuples
Definition: parsenodes.h:1135
void * palloc(Size size)
Definition: mcxt.c:1062
int errmsg(const char *fmt,...)
Definition: elog.c:909
char * cycle_mark_column
Definition: parsenodes.h:1485
#define elog(elevel,...)
Definition: elog.h:232
Bitmapset * insertedCols
Definition: parsenodes.h:1148
int i
TargetEntry * get_tle_by_resno(List *tlist, AttrNumber resno)
ParseNamespaceItem * addRangeTableEntryForSubquery(ParseState *pstate, Query *subquery, Alias *alias, bool lateral, bool inFromCl)
static void buildRelationAliases(TupleDesc tupdesc, Alias *alias, Alias *eref)
AttrNumber p_varattnosyn
Definition: parse_node.h:307
#define NameStr(name)
Definition: c.h:681
bool name_matches_visible_ENR(ParseState *pstate, const char *refname)
Definition: parse_enr.c:20
List * expandNSItemAttrs(ParseState *pstate, ParseNamespaceItem *nsitem, int sublevels_up, int location)
List * p_ctenamespace
Definition: parse_node.h:189
List * p_joinlist
Definition: parse_node.h:184
Alias * alias
Definition: primnodes.h:72
static ParseNamespaceItem * scanNameSpaceForRefname(ParseState *pstate, const char *refname, int location)
char * get_attname(Oid relid, AttrNumber attnum, bool missing_ok)
Definition: lsyscache.c:825
EphemeralNameRelationType enrtype
bool isLockedRefname(ParseState *pstate, const char *refname)
char * colname
Definition: parsenodes.h:658
Alias * eref
Definition: parsenodes.h:1141
List * ctecolcollations
Definition: parsenodes.h:1515
#define copyObject(obj)
Definition: nodes.h:655
List * coltypes
Definition: parsenodes.h:1127
Relation table_open(Oid relationId, LOCKMODE lockmode)
Definition: table.c:39
Definition: regcomp.c:238
void CheckAttributeNamesTypes(TupleDesc tupdesc, char relkind, int flags)
Definition: heap.c:499
Definition: pg_list.h:50
#define snprintf
Definition: port.h:216
int16 AttrNumber
Definition: attnum.h:21
#define RelationGetRelid(relation)
Definition: rel.h:457
List * p_joinexprs
Definition: parse_node.h:183
#define lfirst_oid(lc)
Definition: pg_list.h:171
Oid LookupNamespaceNoError(const char *nspname)
Definition: namespace.c:2862
Node * colNameToVar(ParseState *pstate, const char *colname, bool localonly, int location)
char * get_func_result_name(Oid functionId)
Definition: funcapi.c:1500
#define QTW_IGNORE_JOINALIASES
Definition: nodeFuncs.h:23
List * p_rtable
Definition: parse_node.h:182