postgresql list and order tables by size

Question

How can I list all the tables of a PostgreSQL database and order them by size?

Answer 1

This will show you the schema name, table name, size pretty and size (needed for sort).

SELECT
  schema_name,
  relname,
  pg_size_pretty(table_size) AS size,
  table_size

FROM (
       SELECT
         pg_catalog.pg_namespace.nspname           AS schema_name,
         relname,
         pg_relation_size(pg_catalog.pg_class.oid) AS table_size

       FROM pg_catalog.pg_class
         JOIN pg_catalog.pg_namespace ON relnamespace = pg_catalog.pg_namespace.oid
     ) t
WHERE schema_name NOT LIKE 'pg_%'
ORDER BY table_size DESC;

I build this based on the solutions from here list of schema with sizes (relative and absolute) in a PostgreSQL database