diff options
Diffstat (limited to 'src/backend/utils/cache/lsyscache.c')
| -rw-r--r-- | src/backend/utils/cache/lsyscache.c | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/src/backend/utils/cache/lsyscache.c b/src/backend/utils/cache/lsyscache.c index 0a4144ba547..6af23429ad8 100644 --- a/src/backend/utils/cache/lsyscache.c +++ b/src/backend/utils/cache/lsyscache.c @@ -20,6 +20,7 @@ #include "bootstrap/bootstrap.h" #include "catalog/pg_amop.h" #include "catalog/pg_amproc.h" +#include "catalog/pg_collation.h" #include "catalog/pg_constraint.h" #include "catalog/pg_namespace.h" #include "catalog/pg_opclass.h" @@ -903,6 +904,33 @@ get_atttypmod(Oid relid, AttrNumber attnum) } /* + * get_attcollation + * + * Given the relation id and the attribute number, + * return the "attcollation" field from the attribute relation. + */ +Oid +get_attcollation(Oid relid, AttrNumber attnum) +{ + HeapTuple tp; + + tp = SearchSysCache2(ATTNUM, + ObjectIdGetDatum(relid), + Int16GetDatum(attnum)); + if (HeapTupleIsValid(tp)) + { + Form_pg_attribute att_tup = (Form_pg_attribute) GETSTRUCT(tp); + Oid result; + + result = att_tup->attcollation; + ReleaseSysCache(tp); + return result; + } + else + return InvalidOid; +} + +/* * get_atttypetypmod * * A two-fer: given the relation id and the attribute number, @@ -931,6 +959,36 @@ get_atttypetypmod(Oid relid, AttrNumber attnum, ReleaseSysCache(tp); } +/* ---------- COLLATION CACHE ---------- */ + +/* + * get_collation_name + * Returns the name of a given pg_collation entry. + * + * Returns a palloc'd copy of the string, or NULL if no such constraint. + * + * NOTE: since collation name is not unique, be wary of code that uses this + * for anything except preparing error messages. + */ +char * +get_collation_name(Oid colloid) +{ + HeapTuple tp; + + tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(colloid)); + if (HeapTupleIsValid(tp)) + { + Form_pg_collation colltup = (Form_pg_collation) GETSTRUCT(tp); + char *result; + + result = pstrdup(NameStr(colltup->collname)); + ReleaseSysCache(tp); + return result; + } + else + return NULL; +} + /* ---------- CONSTRAINT CACHE ---------- */ /* @@ -2523,6 +2581,42 @@ get_typmodout(Oid typid) } #endif /* NOT_USED */ +/* + * get_typcollation + * + * Given the type OID, return the type's typcollation attribute. + */ +Oid +get_typcollation(Oid typid) +{ + HeapTuple tp; + + tp = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typid)); + if (HeapTupleIsValid(tp)) + { + Form_pg_type typtup = (Form_pg_type) GETSTRUCT(tp); + Oid result; + + result = typtup->typcollation; + ReleaseSysCache(tp); + return result; + } + else + return InvalidOid; +} + + +/* + * type_is_collatable + * + * Return whether the type cares about collations + */ +bool +type_is_collatable(Oid typid) +{ + return OidIsValid(get_typcollation(typid)); +} + /* ---------- STATISTICS CACHE ---------- */ |