Hello, I would like to create a constraint that involves the system table. CREATE TABLE metadata_tables ( schemaname text REFERENCES pg_namespace(nspname) ON DELETE CASCADE CONSTRAINT valid_schema CHECK (schemaname != 'public' AND schemaname != 'information_schema' AND schemaname NOT LIKE 'pg_%'), tablename text, source text ) WITH (OIDS=FALSE) ; Basically, I only want to allow that the user can use schemanames present in the current database as input in the column schemaname. When I try to create this table, I get an error that it is a system table. ERROR: permission denied: "pg_namespace" is a system catalog However, when looking at the system table definition, it has "GRANT SELECT ON TABLE pg_namespace TO public;" - so everybody should be able to query a system table. Why is this not working? What other privileges besides "SELECT" would one need to define a constraint? Thanks for any hint, Andreas -- Andreas Neumann Böschacherstrasse 6, CH-8624 Grüt/Gossau, Switzerland Email: a.neumann@xxxxxxxxx, Web: * http://www.carto.net/ (Carto and SVG resources) * http://www.carto.net/neumann/ (personal page) * http://www.svgopen.org/ (SVG Open Conference) * http://www.geofoto.ch/ (Georeferenced Photos of Switzerland) ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org/
