postgresql查询表的大小
SELECT table_schema || '.' || TABLE_NAME AS table_full_name, pg_size_pretty ( pg_total_relation_size ( '"' || table_schema || '"."' || TABLE_NAME || '"' )) AS SIZE FROM information_schema.tables ORDER BY pg_total_relation_size ( '"' || table_schema || '"."' || TABLE_NAME || '"' ) DESC LIMIT 20;
~~~ 完美!