diff options
Diffstat (limited to 'src/backend/utils/cache/syscache.c')
-rw-r--r-- | src/backend/utils/cache/syscache.c | 67 |
1 files changed, 66 insertions, 1 deletions
diff --git a/src/backend/utils/cache/syscache.c b/src/backend/utils/cache/syscache.c index 0e114f36968..c9b68b1d8d4 100644 --- a/src/backend/utils/cache/syscache.c +++ b/src/backend/utils/cache/syscache.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/utils/cache/syscache.c,v 1.84 2002/07/25 10:07:12 ishii Exp $ + * $Header: /cvsroot/pgsql/src/backend/utils/cache/syscache.c,v 1.85 2002/08/02 18:15:08 tgl Exp $ * * NOTES * These routines allow the parser/planner/executor to perform @@ -622,6 +622,71 @@ GetSysCacheOid(int cacheId, return result; } + +/* + * SearchSysCacheAttName + * + * This routine is equivalent to SearchSysCache on the ATTNAME cache, + * except that it will return NULL if the found attribute is marked + * attisdropped. This is convenient for callers that want to act as + * though dropped attributes don't exist. + */ +HeapTuple +SearchSysCacheAttName(Oid relid, const char *attname) +{ + HeapTuple tuple; + + tuple = SearchSysCache(ATTNAME, + ObjectIdGetDatum(relid), + CStringGetDatum(attname), + 0, 0); + if (!HeapTupleIsValid(tuple)) + return NULL; + if (((Form_pg_attribute) GETSTRUCT(tuple))->attisdropped) + { + ReleaseSysCache(tuple); + return NULL; + } + return tuple; +} + +/* + * SearchSysCacheCopyAttName + * + * As above, an attisdropped-aware version of SearchSysCacheCopy. + */ +HeapTuple +SearchSysCacheCopyAttName(Oid relid, const char *attname) +{ + HeapTuple tuple, + newtuple; + + tuple = SearchSysCacheAttName(relid, attname); + if (!HeapTupleIsValid(tuple)) + return tuple; + newtuple = heap_copytuple(tuple); + ReleaseSysCache(tuple); + return newtuple; +} + +/* + * SearchSysCacheExistsAttName + * + * As above, an attisdropped-aware version of SearchSysCacheExists. + */ +bool +SearchSysCacheExistsAttName(Oid relid, const char *attname) +{ + HeapTuple tuple; + + tuple = SearchSysCacheAttName(relid, attname); + if (!HeapTupleIsValid(tuple)) + return false; + ReleaseSysCache(tuple); + return true; +} + + /* * SysCacheGetAttr * |