Postgres table sizes

posgres_size.sql

WITH RECURSIVE pg_inherit(inhrelid, inhparent) AS
    (select inhrelid, inhparent
    FROM pg_inherits
    UNION
    SELECT child.inhrelid, parent.inhparent
    FROM pg_inherit child, pg_inherits parent
    WHERE child.inhparent = parent.inhrelid),
pg_inherit_short AS (SELECT * FROM pg_inherit WHERE inhparent NOT IN (SELECT inhrelid FROM pg_inherit))
SELECT table_schema
    , TABLE_NAME
    , row_estimate
    , pg_size_pretty(total_bytes) AS total
    , pg_size_pretty(index_bytes) AS INDEX
    , pg_size_pretty(toast_bytes) AS toast
    , pg_size_pretty(table_bytes) AS TABLE
  FROM (
    SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes
    FROM (
			 SELECT c.oid
						, nspname AS table_schema
						, relname AS TABLE_NAME
						, SUM(c.reltuples) OVER (partition BY parent) AS row_estimate
						, SUM(pg_total_relation_size(c.oid)) OVER (partition BY parent) AS total_bytes
						, SUM(pg_indexes_size(c.oid)) OVER (partition BY parent) AS index_bytes
						, SUM(pg_total_relation_size(reltoastrelid)) OVER (partition BY parent) AS toast_bytes
						, parent
				FROM (
						SELECT pg_class.oid
								, reltuples
								, relname
								, relnamespace
								, pg_class.reltoastrelid
								, COALESCE(inhparent, pg_class.oid) parent
						FROM pg_class
								LEFT JOIN pg_inherit_short ON inhrelid = oid
						WHERE relkind IN ('r', 'p')
				 ) c
				 LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
  ) a
  WHERE oid = parent
) a
ORDER BY total_bytes DESC
;