gistfile1.txt

SELECT c.relname AS Name,
       pg_size_pretty(pg_relation_size(c.relname::text)) AS Data,
       pg_size_pretty(pg_total_relation_size(c.relname::text)-
           pg_relation_size(c.relname::text)) AS Indices,
       pg_size_pretty(pg_total_relation_size(c.relname::text)) AS Total
  FROM pg_class c
  LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
 WHERE c.relkind IN ('r','')
   AND n.nspname NOT IN ('pg_catalog', 'pg_toast')
   AND pg_table_is_visible(c.oid)
 ORDER BY c.relpages DESC limit 20;