检查每个库占用空间大小

SELECT
  datname AS database_name,
  pg_size_pretty(pg_database_size(datname)) AS total_size
FROM
  pg_database
ORDER BY
  pg_database_size(datname) DESC;

查询库中表占用空间大小

SELECT
  table_name,
  pg_size_pretty(pg_total_relation_size('"' || table_schema || '"."' || table_name || '"')) AS total_size
FROM
  information_schema.tables
WHERE
  table_schema = 'public' -- 如果表位于公共模式中，可以替换为实际的模式名称
ORDER BY
  pg_total_relation_size('"' || table_schema || '"."' || table_name || '"') DESC;