Lars Aksel Opsahl <Lars.Opsahl@xxxxxxxx> writes: >> SELECT relname, pg_size_pretty(pg_relation_size(C.oid)) FROM pg_class C LEFT JOIN pg_namespace N ON (N.oid = C.relnamespace) WHERE nspname = 'pg_catalog' ORDER BY 2 DESC LIMIT 20; can you show the output of this query "ORDER BY 2" is giving you a textual sort of the sizes, which is entirely unhelpful. Try SELECT relname, pg_size_pretty(pg_relation_size(C.oid)) FROM pg_class C LEFT JOIN pg_namespace N ON (N.oid = C.relnamespace) WHERE nspname = 'pg_catalog' ORDER BY pg_relation_size(C.oid) DESC LIMIT 20; regards, tom lane