SELECT
  u.usename AS username,
  r.rolname AS role,
  array_agg(DISTINCT a.rolname) AS member_of,
  array_agg(DISTINCT p.grantor || ':' || p.privilege_type) AS privileges
FROM pg_user u
LEFT JOIN pg_auth_members m ON m.member = u.usesysid
LEFT JOIN pg_roles r ON r.oid = m.roleid
LEFT JOIN pg_auth_members am ON am.member = r.oid
LEFT JOIN pg_roles a ON a.oid = am.roleid
LEFT JOIN (
  SELECT
    grantee,
    grantor,
    privilege_type
  FROM information_schema.role_table_grants
  UNION ALL
  SELECT
    grantee,
    grantor,
    privilege_type
  FROM information_schema.role_column_grants
) p ON p.grantee = r.oid
WHERE u.usename NOT LIKE 'postgres' 
GROUP BY u.usename, r.rolname
ORDER BY u.usename;

这就是我在我的项目中使用的，通过在这个查询中添加COALESCE函数，特权将不再在结果集中显示为“null”