SELECT relname AS "relation", pg_size_pretty ( pg_total_relation_size (C .oid) ) AS "total_size" FROM pg_class C LEFT JOIN pg_namespace N ON (N.oid = C .relnamespace) WHERE nspname NOT IN ( 'pg_catalog', 'information_schema' ) AND C .relkind <> 'i' AND nspname !~ '^pg_toast' ORDER BY pg_total_relation_size (C .oid) DESC LIMIT 5;