🐥 Getting the size of all postgres databases on a server

Here is an SQL statement to get the size of all your PostgreSQL databases.

SELECT 
  d.datname AS Name, 
  pg_catalog.pg_get_userbyid(d.datdba) AS Owner, 
  CASE WHEN pg_catalog.has_database_privilege(d.datname, 'CONNECT') THEN pg_catalog.pg_size_pretty(
    pg_catalog.pg_database_size(d.datname)
  ) ELSE 'No Access' END AS SIZE 
FROM 
  pg_catalog.pg_database d 
ORDER BY 
  CASE WHEN pg_catalog.has_database_privilege(d.datname, 'CONNECT') THEN pg_catalog.pg_database_size(d.datname) ELSE NULL END DESC;

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