1 /*-------------------------------------------------------------------------
4 * code to support accessing and searching namespaces
6 * This is separate from pg_namespace.c, which contains the routines that
7 * directly manipulate the pg_namespace system catalog. This module
8 * provides routines associated with defining a "namespace search path"
9 * and implementing search-path-controlled searches.
12 * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
13 * Portions Copyright (c) 1994, Regents of the University of California
16 * $PostgreSQL: pgsql/src/backend/catalog/namespace.c,v 1.76 2005/06/28 05:08:52 tgl Exp $
18 *-------------------------------------------------------------------------
22 #include "access/xact.h"
23 #include "catalog/dependency.h"
24 #include "catalog/namespace.h"
25 #include "catalog/pg_authid.h"
26 #include "catalog/pg_conversion.h"
27 #include "catalog/pg_namespace.h"
28 #include "catalog/pg_opclass.h"
29 #include "catalog/pg_operator.h"
30 #include "catalog/pg_proc.h"
31 #include "catalog/pg_type.h"
32 #include "commands/dbcommands.h"
33 #include "lib/stringinfo.h"
34 #include "miscadmin.h"
35 #include "nodes/makefuncs.h"
36 #include "storage/backendid.h"
37 #include "storage/ipc.h"
38 #include "utils/acl.h"
39 #include "utils/builtins.h"
40 #include "utils/catcache.h"
41 #include "utils/guc.h"
42 #include "utils/inval.h"
43 #include "utils/lsyscache.h"
44 #include "utils/memutils.h"
45 #include "utils/syscache.h"
49 * The namespace search path is a possibly-empty list of namespace OIDs.
50 * In addition to the explicit list, several implicitly-searched namespaces
53 * 1. If a "special" namespace has been set by PushSpecialNamespace, it is
54 * always searched first. (This is a hack for CREATE SCHEMA.)
56 * 2. If a TEMP table namespace has been initialized in this session, it
57 * is always searched just after any special namespace.
59 * 3. The system catalog namespace is always searched. If the system
60 * namespace is present in the explicit path then it will be searched in
61 * the specified order; otherwise it will be searched after TEMP tables and
62 * *before* the explicit list. (It might seem that the system namespace
63 * should be implicitly last, but this behavior appears to be required by
64 * SQL99. Also, this provides a way to search the system namespace first
65 * without thereby making it the default creation target namespace.)
67 * The default creation target namespace is normally equal to the first
68 * element of the explicit list, but is the "special" namespace when one
69 * has been set. If the explicit list is empty and there is no special
70 * namespace, there is no default target.
72 * In bootstrap mode, the search path is set equal to 'pg_catalog', so that
73 * the system namespace is the only one searched or inserted into.
74 * The initdb script is also careful to set search_path to 'pg_catalog' for
75 * its post-bootstrap standalone backend runs. Otherwise the default search
76 * path is determined by GUC. The factory default path contains the PUBLIC
77 * namespace (if it exists), preceded by the user's personal namespace
80 * If namespaceSearchPathValid is false, then namespaceSearchPath (and other
81 * derived variables) need to be recomputed from namespace_search_path.
82 * We mark it invalid upon an assignment to namespace_search_path or receipt
83 * of a syscache invalidation event for pg_namespace. The recomputation
84 * is done during the next lookup attempt.
86 * Any namespaces mentioned in namespace_search_path that are not readable
87 * by the current user ID are simply left out of namespaceSearchPath; so
88 * we have to be willing to recompute the path when current userid changes.
89 * namespaceUser is the userid the path has been computed for.
92 static List *namespaceSearchPath = NIL;
94 static Oid namespaceUser = InvalidOid;
96 /* default place to create stuff; if InvalidOid, no default */
97 static Oid defaultCreationNamespace = InvalidOid;
99 /* first explicit member of list; usually same as defaultCreationNamespace */
100 static Oid firstExplicitNamespace = InvalidOid;
102 /* The above four values are valid only if namespaceSearchPathValid */
103 static bool namespaceSearchPathValid = true;
106 * myTempNamespace is InvalidOid until and unless a TEMP namespace is set up
107 * in a particular backend session (this happens when a CREATE TEMP TABLE
108 * command is first executed). Thereafter it's the OID of the temp namespace.
110 * myTempNamespaceSubID shows whether we've created the TEMP namespace in the
111 * current subtransaction. The flag propagates up the subtransaction tree,
112 * so the main transaction will correctly recognize the flag if all
113 * intermediate subtransactions commit. When it is InvalidSubTransactionId,
114 * we either haven't made the TEMP namespace yet, or have successfully
115 * committed its creation, depending on whether myTempNamespace is valid.
117 static Oid myTempNamespace = InvalidOid;
119 static SubTransactionId myTempNamespaceSubID = InvalidSubTransactionId;
122 * "Special" namespace for CREATE SCHEMA. If set, it's the first search
123 * path element, and also the default creation namespace.
125 static Oid mySpecialNamespace = InvalidOid;
128 * This is the text equivalent of the search path --- it's the value
129 * of the GUC variable 'search_path'.
131 char *namespace_search_path = NULL;
134 /* Local functions */
135 static void recomputeNamespacePath(void);
136 static void InitTempTableNamespace(void);
137 static void RemoveTempRelations(Oid tempNamespaceId);
138 static void RemoveTempRelationsCallback(int code, Datum arg);
139 static void NamespaceCallback(Datum arg, Oid relid);
141 /* These don't really need to appear in any header file */
142 Datum pg_table_is_visible(PG_FUNCTION_ARGS);
143 Datum pg_type_is_visible(PG_FUNCTION_ARGS);
144 Datum pg_function_is_visible(PG_FUNCTION_ARGS);
145 Datum pg_operator_is_visible(PG_FUNCTION_ARGS);
146 Datum pg_opclass_is_visible(PG_FUNCTION_ARGS);
147 Datum pg_conversion_is_visible(PG_FUNCTION_ARGS);
152 * Given a RangeVar describing an existing relation,
153 * select the proper namespace and look up the relation OID.
155 * If the relation is not found, return InvalidOid if failOK = true,
156 * otherwise raise an error.
159 RangeVarGetRelid(const RangeVar *relation, bool failOK)
165 * We check the catalog name and then ignore it.
167 if (relation->catalogname)
169 if (strcmp(relation->catalogname, get_database_name(MyDatabaseId)) != 0)
171 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
172 errmsg("cross-database references are not implemented: \"%s.%s.%s\"",
173 relation->catalogname, relation->schemaname,
174 relation->relname)));
177 if (relation->schemaname)
179 /* use exact schema given */
180 namespaceId = LookupExplicitNamespace(relation->schemaname);
181 relId = get_relname_relid(relation->relname, namespaceId);
185 /* search the namespace path */
186 relId = RelnameGetRelid(relation->relname);
189 if (!OidIsValid(relId) && !failOK)
191 if (relation->schemaname)
193 (errcode(ERRCODE_UNDEFINED_TABLE),
194 errmsg("relation \"%s.%s\" does not exist",
195 relation->schemaname, relation->relname)));
198 (errcode(ERRCODE_UNDEFINED_TABLE),
199 errmsg("relation \"%s\" does not exist",
200 relation->relname)));
206 * RangeVarGetCreationNamespace
207 * Given a RangeVar describing a to-be-created relation,
208 * choose which namespace to create it in.
210 * Note: calling this may result in a CommandCounterIncrement operation.
211 * That will happen on the first request for a temp table in any particular
212 * backend run; we will need to either create or clean out the temp schema.
215 RangeVarGetCreationNamespace(const RangeVar *newRelation)
220 * We check the catalog name and then ignore it.
222 if (newRelation->catalogname)
224 if (strcmp(newRelation->catalogname, get_database_name(MyDatabaseId)) != 0)
226 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
227 errmsg("cross-database references are not implemented: \"%s.%s.%s\"",
228 newRelation->catalogname, newRelation->schemaname,
229 newRelation->relname)));
232 if (newRelation->istemp)
234 /* TEMP tables are created in our backend-local temp namespace */
235 if (newRelation->schemaname)
237 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
238 errmsg("temporary tables may not specify a schema name")));
239 /* Initialize temp namespace if first time through */
240 if (!OidIsValid(myTempNamespace))
241 InitTempTableNamespace();
242 return myTempNamespace;
245 if (newRelation->schemaname)
247 /* use exact schema given */
248 namespaceId = GetSysCacheOid(NAMESPACENAME,
249 CStringGetDatum(newRelation->schemaname),
251 if (!OidIsValid(namespaceId))
253 (errcode(ERRCODE_UNDEFINED_SCHEMA),
254 errmsg("schema \"%s\" does not exist",
255 newRelation->schemaname)));
256 /* we do not check for USAGE rights here! */
260 /* use the default creation namespace */
261 recomputeNamespacePath();
262 namespaceId = defaultCreationNamespace;
263 if (!OidIsValid(namespaceId))
265 (errcode(ERRCODE_UNDEFINED_SCHEMA),
266 errmsg("no schema has been selected to create in")));
269 /* Note: callers will check for CREATE rights when appropriate */
276 * Try to resolve an unqualified relation name.
277 * Returns OID if relation found in search path, else InvalidOid.
280 RelnameGetRelid(const char *relname)
285 recomputeNamespacePath();
287 foreach(l, namespaceSearchPath)
289 Oid namespaceId = lfirst_oid(l);
291 relid = get_relname_relid(relname, namespaceId);
292 if (OidIsValid(relid))
296 /* Not found in path */
303 * Determine whether a relation (identified by OID) is visible in the
304 * current search path. Visible means "would be found by searching
305 * for the unqualified relation name".
308 RelationIsVisible(Oid relid)
311 Form_pg_class relform;
315 reltup = SearchSysCache(RELOID,
316 ObjectIdGetDatum(relid),
318 if (!HeapTupleIsValid(reltup))
319 elog(ERROR, "cache lookup failed for relation %u", relid);
320 relform = (Form_pg_class) GETSTRUCT(reltup);
322 recomputeNamespacePath();
325 * Quick check: if it ain't in the path at all, it ain't visible.
326 * Items in the system namespace are surely in the path and so we
327 * needn't even do list_member_oid() for them.
329 relnamespace = relform->relnamespace;
330 if (relnamespace != PG_CATALOG_NAMESPACE &&
331 !list_member_oid(namespaceSearchPath, relnamespace))
336 * If it is in the path, it might still not be visible; it could
337 * be hidden by another relation of the same name earlier in the
338 * path. So we must do a slow check to see if this rel would be
339 * found by RelnameGetRelid.
341 char *relname = NameStr(relform->relname);
343 visible = (RelnameGetRelid(relname) == relid);
346 ReleaseSysCache(reltup);
354 * Try to resolve an unqualified datatype name.
355 * Returns OID if type found in search path, else InvalidOid.
357 * This is essentially the same as RelnameGetRelid.
360 TypenameGetTypid(const char *typname)
365 recomputeNamespacePath();
367 foreach(l, namespaceSearchPath)
369 Oid namespaceId = lfirst_oid(l);
371 typid = GetSysCacheOid(TYPENAMENSP,
372 PointerGetDatum(typname),
373 ObjectIdGetDatum(namespaceId),
375 if (OidIsValid(typid))
379 /* Not found in path */
385 * Determine whether a type (identified by OID) is visible in the
386 * current search path. Visible means "would be found by searching
387 * for the unqualified type name".
390 TypeIsVisible(Oid typid)
393 Form_pg_type typform;
397 typtup = SearchSysCache(TYPEOID,
398 ObjectIdGetDatum(typid),
400 if (!HeapTupleIsValid(typtup))
401 elog(ERROR, "cache lookup failed for type %u", typid);
402 typform = (Form_pg_type) GETSTRUCT(typtup);
404 recomputeNamespacePath();
407 * Quick check: if it ain't in the path at all, it ain't visible.
408 * Items in the system namespace are surely in the path and so we
409 * needn't even do list_member_oid() for them.
411 typnamespace = typform->typnamespace;
412 if (typnamespace != PG_CATALOG_NAMESPACE &&
413 !list_member_oid(namespaceSearchPath, typnamespace))
418 * If it is in the path, it might still not be visible; it could
419 * be hidden by another type of the same name earlier in the path.
420 * So we must do a slow check to see if this type would be found
421 * by TypenameGetTypid.
423 char *typname = NameStr(typform->typname);
425 visible = (TypenameGetTypid(typname) == typid);
428 ReleaseSysCache(typtup);
435 * FuncnameGetCandidates
436 * Given a possibly-qualified function name and argument count,
437 * retrieve a list of the possible matches.
439 * If nargs is -1, we return all functions matching the given name,
440 * regardless of argument count.
442 * We search a single namespace if the function name is qualified, else
443 * all namespaces in the search path. The return list will never contain
444 * multiple entries with identical argument lists --- in the multiple-
445 * namespace case, we arrange for entries in earlier namespaces to mask
446 * identical entries in later namespaces.
449 FuncnameGetCandidates(List *names, int nargs)
451 FuncCandidateList resultList = NULL;
458 /* deconstruct the name list */
459 DeconstructQualifiedName(names, &schemaname, &funcname);
463 /* use exact schema given */
464 namespaceId = LookupExplicitNamespace(schemaname);
468 /* flag to indicate we need namespace search */
469 namespaceId = InvalidOid;
470 recomputeNamespacePath();
473 /* Search syscache by name only */
474 catlist = SearchSysCacheList(PROCNAMEARGSNSP, 1,
475 CStringGetDatum(funcname),
478 for (i = 0; i < catlist->n_members; i++)
480 HeapTuple proctup = &catlist->members[i]->tuple;
481 Form_pg_proc procform = (Form_pg_proc) GETSTRUCT(proctup);
482 int pronargs = procform->pronargs;
484 FuncCandidateList newResult;
486 /* Ignore if it doesn't match requested argument count */
487 if (nargs >= 0 && pronargs != nargs)
490 if (OidIsValid(namespaceId))
492 /* Consider only procs in specified namespace */
493 if (procform->pronamespace != namespaceId)
495 /* No need to check args, they must all be different */
499 /* Consider only procs that are in the search path */
502 foreach(nsp, namespaceSearchPath)
504 if (procform->pronamespace == lfirst_oid(nsp))
509 continue; /* proc is not in search path */
512 * Okay, it's in the search path, but does it have the same
513 * arguments as something we already accepted? If so, keep
514 * only the one that appears earlier in the search path.
516 * If we have an ordered list from SearchSysCacheList (the normal
517 * case), then any conflicting proc must immediately adjoin
518 * this one in the list, so we only need to look at the newest
519 * result item. If we have an unordered list, we have to scan
520 * the whole result list.
524 FuncCandidateList prevResult;
526 if (catlist->ordered)
528 if (pronargs == resultList->nargs &&
529 memcmp(procform->proargtypes.values,
531 pronargs * sizeof(Oid)) == 0)
532 prevResult = resultList;
538 for (prevResult = resultList;
540 prevResult = prevResult->next)
542 if (pronargs == prevResult->nargs &&
543 memcmp(procform->proargtypes.values,
545 pronargs * sizeof(Oid)) == 0)
551 /* We have a match with a previous result */
552 Assert(pathpos != prevResult->pathpos);
553 if (pathpos > prevResult->pathpos)
554 continue; /* keep previous result */
555 /* replace previous result */
556 prevResult->pathpos = pathpos;
557 prevResult->oid = HeapTupleGetOid(proctup);
558 continue; /* args are same, of course */
564 * Okay to add it to result list
566 newResult = (FuncCandidateList)
567 palloc(sizeof(struct _FuncCandidateList) - sizeof(Oid)
568 + pronargs * sizeof(Oid));
569 newResult->pathpos = pathpos;
570 newResult->oid = HeapTupleGetOid(proctup);
571 newResult->nargs = pronargs;
572 memcpy(newResult->args, procform->proargtypes.values,
573 pronargs * sizeof(Oid));
575 newResult->next = resultList;
576 resultList = newResult;
579 ReleaseSysCacheList(catlist);
586 * Determine whether a function (identified by OID) is visible in the
587 * current search path. Visible means "would be found by searching
588 * for the unqualified function name with exact argument matches".
591 FunctionIsVisible(Oid funcid)
594 Form_pg_proc procform;
598 proctup = SearchSysCache(PROCOID,
599 ObjectIdGetDatum(funcid),
601 if (!HeapTupleIsValid(proctup))
602 elog(ERROR, "cache lookup failed for function %u", funcid);
603 procform = (Form_pg_proc) GETSTRUCT(proctup);
605 recomputeNamespacePath();
608 * Quick check: if it ain't in the path at all, it ain't visible.
609 * Items in the system namespace are surely in the path and so we
610 * needn't even do list_member_oid() for them.
612 pronamespace = procform->pronamespace;
613 if (pronamespace != PG_CATALOG_NAMESPACE &&
614 !list_member_oid(namespaceSearchPath, pronamespace))
619 * If it is in the path, it might still not be visible; it could
620 * be hidden by another proc of the same name and arguments
621 * earlier in the path. So we must do a slow check to see if this
622 * is the same proc that would be found by FuncnameGetCandidates.
624 char *proname = NameStr(procform->proname);
625 int nargs = procform->pronargs;
626 FuncCandidateList clist;
630 clist = FuncnameGetCandidates(list_make1(makeString(proname)), nargs);
632 for (; clist; clist = clist->next)
634 if (memcmp(clist->args, procform->proargtypes.values,
635 nargs * sizeof(Oid)) == 0)
637 /* Found the expected entry; is it the right proc? */
638 visible = (clist->oid == funcid);
644 ReleaseSysCache(proctup);
651 * OpernameGetCandidates
652 * Given a possibly-qualified operator name and operator kind,
653 * retrieve a list of the possible matches.
655 * If oprkind is '\0', we return all operators matching the given name,
656 * regardless of arguments.
658 * We search a single namespace if the operator name is qualified, else
659 * all namespaces in the search path. The return list will never contain
660 * multiple entries with identical argument lists --- in the multiple-
661 * namespace case, we arrange for entries in earlier namespaces to mask
662 * identical entries in later namespaces.
664 * The returned items always have two args[] entries --- one or the other
665 * will be InvalidOid for a prefix or postfix oprkind. nargs is 2, too.
668 OpernameGetCandidates(List *names, char oprkind)
670 FuncCandidateList resultList = NULL;
671 char *resultSpace = NULL;
679 /* deconstruct the name list */
680 DeconstructQualifiedName(names, &schemaname, &opername);
684 /* use exact schema given */
685 namespaceId = LookupExplicitNamespace(schemaname);
689 /* flag to indicate we need namespace search */
690 namespaceId = InvalidOid;
691 recomputeNamespacePath();
694 /* Search syscache by name only */
695 catlist = SearchSysCacheList(OPERNAMENSP, 1,
696 CStringGetDatum(opername),
700 * In typical scenarios, most if not all of the operators found by the
701 * catcache search will end up getting returned; and there can be
702 * quite a few, for common operator names such as '=' or '+'. To
703 * reduce the time spent in palloc, we allocate the result space as an
704 * array large enough to hold all the operators. The original coding
705 * of this routine did a separate palloc for each operator, but
706 * profiling revealed that the pallocs used an unreasonably large
707 * fraction of parsing time.
709 #define SPACE_PER_OP MAXALIGN(sizeof(struct _FuncCandidateList) + sizeof(Oid))
711 if (catlist->n_members > 0)
712 resultSpace = palloc(catlist->n_members * SPACE_PER_OP);
714 for (i = 0; i < catlist->n_members; i++)
716 HeapTuple opertup = &catlist->members[i]->tuple;
717 Form_pg_operator operform = (Form_pg_operator) GETSTRUCT(opertup);
719 FuncCandidateList newResult;
721 /* Ignore operators of wrong kind, if specific kind requested */
722 if (oprkind && operform->oprkind != oprkind)
725 if (OidIsValid(namespaceId))
727 /* Consider only opers in specified namespace */
728 if (operform->oprnamespace != namespaceId)
730 /* No need to check args, they must all be different */
734 /* Consider only opers that are in the search path */
737 foreach(nsp, namespaceSearchPath)
739 if (operform->oprnamespace == lfirst_oid(nsp))
744 continue; /* oper is not in search path */
747 * Okay, it's in the search path, but does it have the same
748 * arguments as something we already accepted? If so, keep
749 * only the one that appears earlier in the search path.
751 * If we have an ordered list from SearchSysCacheList (the normal
752 * case), then any conflicting oper must immediately adjoin
753 * this one in the list, so we only need to look at the newest
754 * result item. If we have an unordered list, we have to scan
755 * the whole result list.
759 FuncCandidateList prevResult;
761 if (catlist->ordered)
763 if (operform->oprleft == resultList->args[0] &&
764 operform->oprright == resultList->args[1])
765 prevResult = resultList;
771 for (prevResult = resultList;
773 prevResult = prevResult->next)
775 if (operform->oprleft == prevResult->args[0] &&
776 operform->oprright == prevResult->args[1])
782 /* We have a match with a previous result */
783 Assert(pathpos != prevResult->pathpos);
784 if (pathpos > prevResult->pathpos)
785 continue; /* keep previous result */
786 /* replace previous result */
787 prevResult->pathpos = pathpos;
788 prevResult->oid = HeapTupleGetOid(opertup);
789 continue; /* args are same, of course */
795 * Okay to add it to result list
797 newResult = (FuncCandidateList) (resultSpace + nextResult);
798 nextResult += SPACE_PER_OP;
800 newResult->pathpos = pathpos;
801 newResult->oid = HeapTupleGetOid(opertup);
802 newResult->nargs = 2;
803 newResult->args[0] = operform->oprleft;
804 newResult->args[1] = operform->oprright;
805 newResult->next = resultList;
806 resultList = newResult;
809 ReleaseSysCacheList(catlist);
816 * Determine whether an operator (identified by OID) is visible in the
817 * current search path. Visible means "would be found by searching
818 * for the unqualified operator name with exact argument matches".
821 OperatorIsVisible(Oid oprid)
824 Form_pg_operator oprform;
828 oprtup = SearchSysCache(OPEROID,
829 ObjectIdGetDatum(oprid),
831 if (!HeapTupleIsValid(oprtup))
832 elog(ERROR, "cache lookup failed for operator %u", oprid);
833 oprform = (Form_pg_operator) GETSTRUCT(oprtup);
835 recomputeNamespacePath();
838 * Quick check: if it ain't in the path at all, it ain't visible.
839 * Items in the system namespace are surely in the path and so we
840 * needn't even do list_member_oid() for them.
842 oprnamespace = oprform->oprnamespace;
843 if (oprnamespace != PG_CATALOG_NAMESPACE &&
844 !list_member_oid(namespaceSearchPath, oprnamespace))
849 * If it is in the path, it might still not be visible; it could
850 * be hidden by another operator of the same name and arguments
851 * earlier in the path. So we must do a slow check to see if this
852 * is the same operator that would be found by
853 * OpernameGetCandidates.
855 char *oprname = NameStr(oprform->oprname);
856 FuncCandidateList clist;
860 clist = OpernameGetCandidates(list_make1(makeString(oprname)),
863 for (; clist; clist = clist->next)
865 if (clist->args[0] == oprform->oprleft &&
866 clist->args[1] == oprform->oprright)
868 /* Found the expected entry; is it the right op? */
869 visible = (clist->oid == oprid);
875 ReleaseSysCache(oprtup);
882 * OpclassGetCandidates
883 * Given an index access method OID, retrieve a list of all the
884 * opclasses for that AM that are visible in the search path.
886 * NOTE: the opcname_tmp field in the returned structs should not be used
887 * by callers, because it points at syscache entries that we release at
888 * the end of this routine. If any callers needed the name information,
889 * we could pstrdup() the names ... but at present it'd be wasteful.
892 OpclassGetCandidates(Oid amid)
894 OpclassCandidateList resultList = NULL;
898 /* Search syscache by AM OID only */
899 catlist = SearchSysCacheList(CLAAMNAMENSP, 1,
900 ObjectIdGetDatum(amid),
903 recomputeNamespacePath();
905 for (i = 0; i < catlist->n_members; i++)
907 HeapTuple opctup = &catlist->members[i]->tuple;
908 Form_pg_opclass opcform = (Form_pg_opclass) GETSTRUCT(opctup);
910 OpclassCandidateList newResult;
913 /* Consider only opclasses that are in the search path */
914 foreach(nsp, namespaceSearchPath)
916 if (opcform->opcnamespace == lfirst_oid(nsp))
921 continue; /* opclass is not in search path */
924 * Okay, it's in the search path, but does it have the same name
925 * as something we already accepted? If so, keep only the one
926 * that appears earlier in the search path.
928 * If we have an ordered list from SearchSysCacheList (the normal
929 * case), then any conflicting opclass must immediately adjoin
930 * this one in the list, so we only need to look at the newest
931 * result item. If we have an unordered list, we have to scan the
936 OpclassCandidateList prevResult;
938 if (catlist->ordered)
940 if (strcmp(NameStr(opcform->opcname),
941 resultList->opcname_tmp) == 0)
942 prevResult = resultList;
948 for (prevResult = resultList;
950 prevResult = prevResult->next)
952 if (strcmp(NameStr(opcform->opcname),
953 prevResult->opcname_tmp) == 0)
959 /* We have a match with a previous result */
960 Assert(pathpos != prevResult->pathpos);
961 if (pathpos > prevResult->pathpos)
962 continue; /* keep previous result */
963 /* replace previous result */
964 prevResult->opcname_tmp = NameStr(opcform->opcname);
965 prevResult->pathpos = pathpos;
966 prevResult->oid = HeapTupleGetOid(opctup);
967 prevResult->opcintype = opcform->opcintype;
968 prevResult->opcdefault = opcform->opcdefault;
969 prevResult->opckeytype = opcform->opckeytype;
975 * Okay to add it to result list
977 newResult = (OpclassCandidateList)
978 palloc(sizeof(struct _OpclassCandidateList));
979 newResult->opcname_tmp = NameStr(opcform->opcname);
980 newResult->pathpos = pathpos;
981 newResult->oid = HeapTupleGetOid(opctup);
982 newResult->opcintype = opcform->opcintype;
983 newResult->opcdefault = opcform->opcdefault;
984 newResult->opckeytype = opcform->opckeytype;
985 newResult->next = resultList;
986 resultList = newResult;
989 ReleaseSysCacheList(catlist);
995 * OpclassnameGetOpcid
996 * Try to resolve an unqualified index opclass name.
997 * Returns OID if opclass found in search path, else InvalidOid.
999 * This is essentially the same as TypenameGetTypid, but we have to have
1000 * an extra argument for the index AM OID.
1003 OpclassnameGetOpcid(Oid amid, const char *opcname)
1008 recomputeNamespacePath();
1010 foreach(l, namespaceSearchPath)
1012 Oid namespaceId = lfirst_oid(l);
1014 opcid = GetSysCacheOid(CLAAMNAMENSP,
1015 ObjectIdGetDatum(amid),
1016 PointerGetDatum(opcname),
1017 ObjectIdGetDatum(namespaceId),
1019 if (OidIsValid(opcid))
1023 /* Not found in path */
1029 * Determine whether an opclass (identified by OID) is visible in the
1030 * current search path. Visible means "would be found by searching
1031 * for the unqualified opclass name".
1034 OpclassIsVisible(Oid opcid)
1037 Form_pg_opclass opcform;
1041 opctup = SearchSysCache(CLAOID,
1042 ObjectIdGetDatum(opcid),
1044 if (!HeapTupleIsValid(opctup))
1045 elog(ERROR, "cache lookup failed for opclass %u", opcid);
1046 opcform = (Form_pg_opclass) GETSTRUCT(opctup);
1048 recomputeNamespacePath();
1051 * Quick check: if it ain't in the path at all, it ain't visible.
1052 * Items in the system namespace are surely in the path and so we
1053 * needn't even do list_member_oid() for them.
1055 opcnamespace = opcform->opcnamespace;
1056 if (opcnamespace != PG_CATALOG_NAMESPACE &&
1057 !list_member_oid(namespaceSearchPath, opcnamespace))
1062 * If it is in the path, it might still not be visible; it could
1063 * be hidden by another opclass of the same name earlier in the
1064 * path. So we must do a slow check to see if this opclass would
1065 * be found by OpclassnameGetOpcid.
1067 char *opcname = NameStr(opcform->opcname);
1069 visible = (OpclassnameGetOpcid(opcform->opcamid, opcname) == opcid);
1072 ReleaseSysCache(opctup);
1078 * ConversionGetConid
1079 * Try to resolve an unqualified conversion name.
1080 * Returns OID if conversion found in search path, else InvalidOid.
1082 * This is essentially the same as RelnameGetRelid.
1085 ConversionGetConid(const char *conname)
1090 recomputeNamespacePath();
1092 foreach(l, namespaceSearchPath)
1094 Oid namespaceId = lfirst_oid(l);
1096 conid = GetSysCacheOid(CONNAMENSP,
1097 PointerGetDatum(conname),
1098 ObjectIdGetDatum(namespaceId),
1100 if (OidIsValid(conid))
1104 /* Not found in path */
1109 * ConversionIsVisible
1110 * Determine whether a conversion (identified by OID) is visible in the
1111 * current search path. Visible means "would be found by searching
1112 * for the unqualified conversion name".
1115 ConversionIsVisible(Oid conid)
1118 Form_pg_conversion conform;
1122 contup = SearchSysCache(CONOID,
1123 ObjectIdGetDatum(conid),
1125 if (!HeapTupleIsValid(contup))
1126 elog(ERROR, "cache lookup failed for conversion %u", conid);
1127 conform = (Form_pg_conversion) GETSTRUCT(contup);
1129 recomputeNamespacePath();
1132 * Quick check: if it ain't in the path at all, it ain't visible.
1133 * Items in the system namespace are surely in the path and so we
1134 * needn't even do list_member_oid() for them.
1136 connamespace = conform->connamespace;
1137 if (connamespace != PG_CATALOG_NAMESPACE &&
1138 !list_member_oid(namespaceSearchPath, connamespace))
1143 * If it is in the path, it might still not be visible; it could
1144 * be hidden by another conversion of the same name earlier in the
1145 * path. So we must do a slow check to see if this conversion
1146 * would be found by ConversionGetConid.
1148 char *conname = NameStr(conform->conname);
1150 visible = (ConversionGetConid(conname) == conid);
1153 ReleaseSysCache(contup);
1159 * DeconstructQualifiedName
1160 * Given a possibly-qualified name expressed as a list of String nodes,
1161 * extract the schema name and object name.
1163 * *nspname_p is set to NULL if there is no explicit schema name.
1166 DeconstructQualifiedName(List *names,
1171 char *schemaname = NULL;
1172 char *objname = NULL;
1174 switch (list_length(names))
1177 objname = strVal(linitial(names));
1180 schemaname = strVal(linitial(names));
1181 objname = strVal(lsecond(names));
1184 catalogname = strVal(linitial(names));
1185 schemaname = strVal(lsecond(names));
1186 objname = strVal(lthird(names));
1189 * We check the catalog name and then ignore it.
1191 if (strcmp(catalogname, get_database_name(MyDatabaseId)) != 0)
1193 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1194 errmsg("cross-database references are not implemented: %s",
1195 NameListToString(names))));
1199 (errcode(ERRCODE_SYNTAX_ERROR),
1200 errmsg("improper qualified name (too many dotted names): %s",
1201 NameListToString(names))));
1205 *nspname_p = schemaname;
1206 *objname_p = objname;
1210 * LookupExplicitNamespace
1211 * Process an explicitly-specified schema name: look up the schema
1212 * and verify we have USAGE (lookup) rights in it.
1214 * Returns the namespace OID. Raises ereport if any problem.
1217 LookupExplicitNamespace(const char *nspname)
1220 AclResult aclresult;
1222 namespaceId = GetSysCacheOid(NAMESPACENAME,
1223 CStringGetDatum(nspname),
1225 if (!OidIsValid(namespaceId))
1227 (errcode(ERRCODE_UNDEFINED_SCHEMA),
1228 errmsg("schema \"%s\" does not exist", nspname)));
1230 aclresult = pg_namespace_aclcheck(namespaceId, GetUserId(), ACL_USAGE);
1231 if (aclresult != ACLCHECK_OK)
1232 aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
1239 * QualifiedNameGetCreationNamespace
1240 * Given a possibly-qualified name for an object (in List-of-Values
1241 * format), determine what namespace the object should be created in.
1242 * Also extract and return the object name (last component of list).
1244 * This is *not* used for tables. Hence, the TEMP table namespace is
1245 * never selected as the creation target.
1248 QualifiedNameGetCreationNamespace(List *names, char **objname_p)
1254 /* deconstruct the name list */
1255 DeconstructQualifiedName(names, &schemaname, &objname);
1259 /* use exact schema given */
1260 namespaceId = GetSysCacheOid(NAMESPACENAME,
1261 CStringGetDatum(schemaname),
1263 if (!OidIsValid(namespaceId))
1265 (errcode(ERRCODE_UNDEFINED_SCHEMA),
1266 errmsg("schema \"%s\" does not exist", schemaname)));
1267 /* we do not check for USAGE rights here! */
1271 /* use the default creation namespace */
1272 recomputeNamespacePath();
1273 namespaceId = defaultCreationNamespace;
1274 if (!OidIsValid(namespaceId))
1276 (errcode(ERRCODE_UNDEFINED_SCHEMA),
1277 errmsg("no schema has been selected to create in")));
1280 /* Note: callers will check for CREATE rights when appropriate */
1282 *objname_p = objname;
1287 * makeRangeVarFromNameList
1288 * Utility routine to convert a qualified-name list into RangeVar form.
1291 makeRangeVarFromNameList(List *names)
1293 RangeVar *rel = makeRangeVar(NULL, NULL);
1295 switch (list_length(names))
1298 rel->relname = strVal(linitial(names));
1301 rel->schemaname = strVal(linitial(names));
1302 rel->relname = strVal(lsecond(names));
1305 rel->catalogname = strVal(linitial(names));
1306 rel->schemaname = strVal(lsecond(names));
1307 rel->relname = strVal(lthird(names));
1311 (errcode(ERRCODE_SYNTAX_ERROR),
1312 errmsg("improper relation name (too many dotted names): %s",
1313 NameListToString(names))));
1322 * Utility routine to convert a qualified-name list into a string.
1324 * This is used primarily to form error messages, and so we do not quote
1325 * the list elements, for the sake of legibility.
1328 NameListToString(List *names)
1330 StringInfoData string;
1333 initStringInfo(&string);
1337 if (l != list_head(names))
1338 appendStringInfoChar(&string, '.');
1339 appendStringInfoString(&string, strVal(lfirst(l)));
1346 * NameListToQuotedString
1347 * Utility routine to convert a qualified-name list into a string.
1349 * Same as above except that names will be double-quoted where necessary,
1350 * so the string could be re-parsed (eg, by textToQualifiedNameList).
1353 NameListToQuotedString(List *names)
1355 StringInfoData string;
1358 initStringInfo(&string);
1362 if (l != list_head(names))
1363 appendStringInfoChar(&string, '.');
1364 appendStringInfoString(&string, quote_identifier(strVal(lfirst(l))));
1371 * isTempNamespace - is the given namespace my temporary-table namespace?
1374 isTempNamespace(Oid namespaceId)
1376 if (OidIsValid(myTempNamespace) && myTempNamespace == namespaceId)
1382 * isOtherTempNamespace - is the given namespace some other backend's
1383 * temporary-table namespace?
1386 isOtherTempNamespace(Oid namespaceId)
1391 /* If it's my own temp namespace, say "false" */
1392 if (isTempNamespace(namespaceId))
1394 /* Else, if the namespace name starts with "pg_temp_", say "true" */
1395 nspname = get_namespace_name(namespaceId);
1397 return false; /* no such namespace? */
1398 result = (strncmp(nspname, "pg_temp_", 8) == 0);
1404 * PushSpecialNamespace - push a "special" namespace onto the front of the
1407 * This is a slightly messy hack intended only for support of CREATE SCHEMA.
1408 * Although the API is defined to allow a stack of pushed namespaces, we
1409 * presently only support one at a time.
1411 * The pushed namespace will be removed from the search path at end of
1412 * transaction, whether commit or abort.
1415 PushSpecialNamespace(Oid namespaceId)
1417 Assert(!OidIsValid(mySpecialNamespace));
1418 mySpecialNamespace = namespaceId;
1419 namespaceSearchPathValid = false;
1423 * PopSpecialNamespace - remove previously pushed special namespace.
1426 PopSpecialNamespace(Oid namespaceId)
1428 Assert(mySpecialNamespace == namespaceId);
1429 mySpecialNamespace = InvalidOid;
1430 namespaceSearchPathValid = false;
1434 * FindConversionByName - find a conversion by possibly qualified name
1437 FindConversionByName(List *name)
1440 char *conversion_name;
1445 /* deconstruct the name list */
1446 DeconstructQualifiedName(name, &schemaname, &conversion_name);
1450 /* use exact schema given */
1451 namespaceId = LookupExplicitNamespace(schemaname);
1452 return FindConversion(conversion_name, namespaceId);
1456 /* search for it in search path */
1457 recomputeNamespacePath();
1459 foreach(l, namespaceSearchPath)
1461 namespaceId = lfirst_oid(l);
1462 conoid = FindConversion(conversion_name, namespaceId);
1463 if (OidIsValid(conoid))
1468 /* Not found in path */
1473 * FindDefaultConversionProc - find default encoding conversion proc
1476 FindDefaultConversionProc(int4 for_encoding, int4 to_encoding)
1481 recomputeNamespacePath();
1483 foreach(l, namespaceSearchPath)
1485 Oid namespaceId = lfirst_oid(l);
1487 proc = FindDefaultConversion(namespaceId, for_encoding, to_encoding);
1488 if (OidIsValid(proc))
1492 /* Not found in path */
1497 * recomputeNamespacePath - recompute path derived variables if needed.
1500 recomputeNamespacePath(void)
1502 Oid roleid = GetUserId();
1509 MemoryContext oldcxt;
1512 * Do nothing if path is already valid.
1514 if (namespaceSearchPathValid && namespaceUser == roleid)
1517 /* Need a modifiable copy of namespace_search_path string */
1518 rawname = pstrdup(namespace_search_path);
1520 /* Parse string into list of identifiers */
1521 if (!SplitIdentifierString(rawname, ',', &namelist))
1523 /* syntax error in name list */
1524 /* this should not happen if GUC checked check_search_path */
1525 elog(ERROR, "invalid list syntax");
1529 * Convert the list of names to a list of OIDs. If any names are not
1530 * recognizable or we don't have read access, just leave them out of
1531 * the list. (We can't raise an error, since the search_path setting
1532 * has already been accepted.) Don't make duplicate entries, either.
1535 foreach(l, namelist)
1537 char *curname = (char *) lfirst(l);
1540 if (strcmp(curname, "$user") == 0)
1542 /* $user --- substitute namespace matching user name, if any */
1545 tuple = SearchSysCache(AUTHOID,
1546 ObjectIdGetDatum(roleid),
1548 if (HeapTupleIsValid(tuple))
1552 rname = NameStr(((Form_pg_authid) GETSTRUCT(tuple))->rolname);
1553 namespaceId = GetSysCacheOid(NAMESPACENAME,
1554 CStringGetDatum(rname),
1556 ReleaseSysCache(tuple);
1557 if (OidIsValid(namespaceId) &&
1558 !list_member_oid(oidlist, namespaceId) &&
1559 pg_namespace_aclcheck(namespaceId, roleid,
1560 ACL_USAGE) == ACLCHECK_OK)
1561 oidlist = lappend_oid(oidlist, namespaceId);
1566 /* normal namespace reference */
1567 namespaceId = GetSysCacheOid(NAMESPACENAME,
1568 CStringGetDatum(curname),
1570 if (OidIsValid(namespaceId) &&
1571 !list_member_oid(oidlist, namespaceId) &&
1572 pg_namespace_aclcheck(namespaceId, roleid,
1573 ACL_USAGE) == ACLCHECK_OK)
1574 oidlist = lappend_oid(oidlist, namespaceId);
1579 * Remember the first member of the explicit list.
1582 firstNS = InvalidOid;
1584 firstNS = linitial_oid(oidlist);
1587 * Add any implicitly-searched namespaces to the list. Note these go
1588 * on the front, not the back; also notice that we do not check USAGE
1589 * permissions for these.
1591 if (!list_member_oid(oidlist, PG_CATALOG_NAMESPACE))
1592 oidlist = lcons_oid(PG_CATALOG_NAMESPACE, oidlist);
1594 if (OidIsValid(myTempNamespace) &&
1595 !list_member_oid(oidlist, myTempNamespace))
1596 oidlist = lcons_oid(myTempNamespace, oidlist);
1598 if (OidIsValid(mySpecialNamespace) &&
1599 !list_member_oid(oidlist, mySpecialNamespace))
1600 oidlist = lcons_oid(mySpecialNamespace, oidlist);
1603 * Now that we've successfully built the new list of namespace OIDs,
1604 * save it in permanent storage.
1606 oldcxt = MemoryContextSwitchTo(TopMemoryContext);
1607 newpath = list_copy(oidlist);
1608 MemoryContextSwitchTo(oldcxt);
1610 /* Now safe to assign to state variable. */
1611 list_free(namespaceSearchPath);
1612 namespaceSearchPath = newpath;
1615 * Update info derived from search path.
1617 firstExplicitNamespace = firstNS;
1618 if (OidIsValid(mySpecialNamespace))
1619 defaultCreationNamespace = mySpecialNamespace;
1621 defaultCreationNamespace = firstNS;
1623 /* Mark the path valid. */
1624 namespaceSearchPathValid = true;
1625 namespaceUser = roleid;
1629 list_free(namelist);
1634 * InitTempTableNamespace
1635 * Initialize temp table namespace on first use in a particular backend
1638 InitTempTableNamespace(void)
1640 char namespaceName[NAMEDATALEN];
1644 * First, do permission check to see if we are authorized to make temp
1645 * tables. We use a nonstandard error message here since
1646 * "databasename: permission denied" might be a tad cryptic.
1648 * Note that ACL_CREATE_TEMP rights are rechecked in
1649 * pg_namespace_aclmask; that's necessary since current user ID could
1650 * change during the session. But there's no need to make the
1651 * namespace in the first place until a temp table creation request is
1652 * made by someone with appropriate rights.
1654 if (pg_database_aclcheck(MyDatabaseId, GetUserId(),
1655 ACL_CREATE_TEMP) != ACLCHECK_OK)
1657 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
1658 errmsg("permission denied to create temporary tables in database \"%s\"",
1659 get_database_name(MyDatabaseId))));
1661 snprintf(namespaceName, sizeof(namespaceName), "pg_temp_%d", MyBackendId);
1663 namespaceId = GetSysCacheOid(NAMESPACENAME,
1664 CStringGetDatum(namespaceName),
1666 if (!OidIsValid(namespaceId))
1669 * First use of this temp namespace in this database; create it.
1670 * The temp namespaces are always owned by the superuser. We
1671 * leave their permissions at default --- i.e., no access except
1672 * to superuser --- to ensure that unprivileged users can't peek
1673 * at other backends' temp tables. This works because the places
1674 * that access the temp namespace for my own backend skip
1675 * permissions checks on it.
1677 namespaceId = NamespaceCreate(namespaceName, BOOTSTRAP_SUPERUSERID);
1678 /* Advance command counter to make namespace visible */
1679 CommandCounterIncrement();
1684 * If the namespace already exists, clean it out (in case the
1685 * former owner crashed without doing so).
1687 RemoveTempRelations(namespaceId);
1691 * Okay, we've prepared the temp namespace ... but it's not committed
1692 * yet, so all our work could be undone by transaction rollback. Set
1693 * flag for AtEOXact_Namespace to know what to do.
1695 myTempNamespace = namespaceId;
1697 /* It should not be done already. */
1698 AssertState(myTempNamespaceSubID == InvalidSubTransactionId);
1699 myTempNamespaceSubID = GetCurrentSubTransactionId();
1701 namespaceSearchPathValid = false; /* need to rebuild list */
1705 * End-of-transaction cleanup for namespaces.
1708 AtEOXact_Namespace(bool isCommit)
1711 * If we abort the transaction in which a temp namespace was selected,
1712 * we'll have to do any creation or cleanout work over again. So,
1713 * just forget the namespace entirely until next time. On the other
1714 * hand, if we commit then register an exit callback to clean out the
1715 * temp tables at backend shutdown. (We only want to register the
1716 * callback once per session, so this is a good place to do it.)
1718 if (myTempNamespaceSubID != InvalidSubTransactionId)
1721 on_shmem_exit(RemoveTempRelationsCallback, 0);
1724 myTempNamespace = InvalidOid;
1725 namespaceSearchPathValid = false; /* need to rebuild list */
1727 myTempNamespaceSubID = InvalidSubTransactionId;
1731 * Clean up if someone failed to do PopSpecialNamespace
1733 if (OidIsValid(mySpecialNamespace))
1735 mySpecialNamespace = InvalidOid;
1736 namespaceSearchPathValid = false; /* need to rebuild list */
1741 * AtEOSubXact_Namespace
1743 * At subtransaction commit, propagate the temp-namespace-creation
1744 * flag to the parent subtransaction.
1746 * At subtransaction abort, forget the flag if we set it up.
1749 AtEOSubXact_Namespace(bool isCommit, SubTransactionId mySubid,
1750 SubTransactionId parentSubid)
1752 if (myTempNamespaceSubID == mySubid)
1755 myTempNamespaceSubID = parentSubid;
1758 myTempNamespaceSubID = InvalidSubTransactionId;
1759 /* TEMP namespace creation failed, so reset state */
1760 myTempNamespace = InvalidOid;
1761 namespaceSearchPathValid = false; /* need to rebuild list */
1767 * Remove all relations in the specified temp namespace.
1769 * This is called at backend shutdown (if we made any temp relations).
1770 * It is also called when we begin using a pre-existing temp namespace,
1771 * in order to clean out any relations that might have been created by
1772 * a crashed backend.
1775 RemoveTempRelations(Oid tempNamespaceId)
1777 ObjectAddress object;
1780 * We want to get rid of everything in the target namespace, but not
1781 * the namespace itself (deleting it only to recreate it later would
1782 * be a waste of cycles). We do this by finding everything that has a
1783 * dependency on the namespace.
1785 object.classId = NamespaceRelationId;
1786 object.objectId = tempNamespaceId;
1787 object.objectSubId = 0;
1789 deleteWhatDependsOn(&object, false);
1793 * Callback to remove temp relations at backend exit.
1796 RemoveTempRelationsCallback(int code, Datum arg)
1798 if (OidIsValid(myTempNamespace)) /* should always be true */
1800 /* Need to ensure we have a usable transaction. */
1801 AbortOutOfAnyTransaction();
1802 StartTransactionCommand();
1804 RemoveTempRelations(myTempNamespace);
1806 CommitTransactionCommand();
1812 * Routines for handling the GUC variable 'search_path'.
1815 /* assign_hook: validate new search_path, do extra actions as needed */
1817 assign_search_path(const char *newval, bool doit, GucSource source)
1823 /* Need a modifiable copy of string */
1824 rawname = pstrdup(newval);
1826 /* Parse string into list of identifiers */
1827 if (!SplitIdentifierString(rawname, ',', &namelist))
1829 /* syntax error in name list */
1831 list_free(namelist);
1836 * If we aren't inside a transaction, we cannot do database access so
1837 * cannot verify the individual names. Must accept the list on faith.
1839 if (source >= PGC_S_INTERACTIVE && IsTransactionState())
1842 * Verify that all the names are either valid namespace names or
1843 * "$user". We do not require $user to correspond to a valid
1844 * namespace. We do not check for USAGE rights, either; should
1847 * When source == PGC_S_TEST, we are checking the argument of an
1848 * ALTER DATABASE SET or ALTER USER SET command. It could be that
1849 * the intended use of the search path is for some other database,
1850 * so we should not error out if it mentions schemas not present
1851 * in the current database. We reduce the message to NOTICE
1854 foreach(l, namelist)
1856 char *curname = (char *) lfirst(l);
1858 if (strcmp(curname, "$user") == 0)
1860 if (!SearchSysCacheExists(NAMESPACENAME,
1861 CStringGetDatum(curname),
1863 ereport((source == PGC_S_TEST) ? NOTICE : ERROR,
1864 (errcode(ERRCODE_UNDEFINED_SCHEMA),
1865 errmsg("schema \"%s\" does not exist", curname)));
1870 list_free(namelist);
1873 * We mark the path as needing recomputation, but don't do anything
1874 * until it's needed. This avoids trying to do database access during
1875 * GUC initialization.
1878 namespaceSearchPathValid = false;
1884 * InitializeSearchPath: initialize module during InitPostgres.
1886 * This is called after we are up enough to be able to do catalog lookups.
1889 InitializeSearchPath(void)
1891 if (IsBootstrapProcessingMode())
1894 * In bootstrap mode, the search path must be 'pg_catalog' so that
1895 * tables are created in the proper namespace; ignore the GUC
1898 MemoryContext oldcxt;
1900 oldcxt = MemoryContextSwitchTo(TopMemoryContext);
1901 namespaceSearchPath = list_make1_oid(PG_CATALOG_NAMESPACE);
1902 MemoryContextSwitchTo(oldcxt);
1903 defaultCreationNamespace = PG_CATALOG_NAMESPACE;
1904 firstExplicitNamespace = PG_CATALOG_NAMESPACE;
1905 namespaceSearchPathValid = true;
1906 namespaceUser = GetUserId();
1911 * In normal mode, arrange for a callback on any syscache
1912 * invalidation of pg_namespace rows.
1914 CacheRegisterSyscacheCallback(NAMESPACEOID,
1917 /* Force search path to be recomputed on next use */
1918 namespaceSearchPathValid = false;
1924 * Syscache inval callback function
1927 NamespaceCallback(Datum arg, Oid relid)
1929 /* Force search path to be recomputed on next use */
1930 namespaceSearchPathValid = false;
1934 * Fetch the active search path. The return value is a palloc'ed list
1935 * of OIDs; the caller is responsible for freeing this storage as
1938 * The returned list includes the implicitly-prepended namespaces only if
1939 * includeImplicit is true.
1942 fetch_search_path(bool includeImplicit)
1946 recomputeNamespacePath();
1948 result = list_copy(namespaceSearchPath);
1949 if (!includeImplicit)
1951 while (result && linitial_oid(result) != firstExplicitNamespace)
1952 result = list_delete_first(result);
1959 * Export the FooIsVisible functions as SQL-callable functions.
1963 pg_table_is_visible(PG_FUNCTION_ARGS)
1965 Oid oid = PG_GETARG_OID(0);
1967 PG_RETURN_BOOL(RelationIsVisible(oid));
1971 pg_type_is_visible(PG_FUNCTION_ARGS)
1973 Oid oid = PG_GETARG_OID(0);
1975 PG_RETURN_BOOL(TypeIsVisible(oid));
1979 pg_function_is_visible(PG_FUNCTION_ARGS)
1981 Oid oid = PG_GETARG_OID(0);
1983 PG_RETURN_BOOL(FunctionIsVisible(oid));
1987 pg_operator_is_visible(PG_FUNCTION_ARGS)
1989 Oid oid = PG_GETARG_OID(0);
1991 PG_RETURN_BOOL(OperatorIsVisible(oid));
1995 pg_opclass_is_visible(PG_FUNCTION_ARGS)
1997 Oid oid = PG_GETARG_OID(0);
1999 PG_RETURN_BOOL(OpclassIsVisible(oid));
2003 pg_conversion_is_visible(PG_FUNCTION_ARGS)
2005 Oid oid = PG_GETARG_OID(0);
2007 PG_RETURN_BOOL(ConversionIsVisible(oid));