diff options
Diffstat (limited to 'src/backend/utils/adt/misc.c')
| -rw-r--r-- | src/backend/utils/adt/misc.c | 51 |
1 files changed, 35 insertions, 16 deletions
diff --git a/src/backend/utils/adt/misc.c b/src/backend/utils/adt/misc.c index 829ce59888c..bf06ec048ff 100644 --- a/src/backend/utils/adt/misc.c +++ b/src/backend/utils/adt/misc.c @@ -528,30 +528,49 @@ pg_collation_for(PG_FUNCTION_ARGS) /* - * information_schema support functions + * pg_relation_is_updatable - determine which update events the specified + * relation supports. * - * Test whether a view (identified by pg_class OID) is insertable-into or - * updatable. The latter requires delete capability too. This is an - * artifact of the way the SQL standard defines the information_schema views: - * if we defined separate functions for update and delete, we'd double the - * work required to compute the view columns. - * - * These rely on relation_is_updatable(), which is in rewriteHandler.c. + * This relies on relation_is_updatable() in rewriteHandler.c, which see + * for additional information. */ Datum -pg_view_is_insertable(PG_FUNCTION_ARGS) +pg_relation_is_updatable(PG_FUNCTION_ARGS) { - Oid viewoid = PG_GETARG_OID(0); - int req_events = (1 << CMD_INSERT); + Oid reloid = PG_GETARG_OID(0); + bool include_triggers = PG_GETARG_BOOL(1); - PG_RETURN_BOOL(relation_is_updatable(viewoid, req_events)); + PG_RETURN_INT32(relation_is_updatable(reloid, include_triggers)); } +/* + * pg_column_is_updatable - determine whether a column is updatable + * + * Currently we just check whether the column's relation is updatable. + * Eventually we might allow views to have some updatable and some + * non-updatable columns. + * + * Also, this function encapsulates the decision about just what + * information_schema.columns.is_updatable actually means. It's not clear + * whether deletability of the column's relation should be required, so + * we want that decision in C code where we could change it without initdb. + */ Datum -pg_view_is_updatable(PG_FUNCTION_ARGS) +pg_column_is_updatable(PG_FUNCTION_ARGS) { - Oid viewoid = PG_GETARG_OID(0); - int req_events = (1 << CMD_UPDATE) | (1 << CMD_DELETE); + Oid reloid = PG_GETARG_OID(0); + AttrNumber attnum = PG_GETARG_INT16(1); + bool include_triggers = PG_GETARG_BOOL(2); + int events; + + /* System columns are never updatable */ + if (attnum <= 0) + PG_RETURN_BOOL(false); + + events = relation_is_updatable(reloid, include_triggers); + + /* We require both updatability and deletability of the relation */ +#define REQ_EVENTS ((1 << CMD_UPDATE) | (1 << CMD_DELETE)) - PG_RETURN_BOOL(relation_is_updatable(viewoid, req_events)); + PG_RETURN_BOOL((events & REQ_EVENTS) == REQ_EVENTS); } |