Get DB owner's name in PostgreSql

I have DB "test" in PostgreSql. I want to write sql to get owner my database.

You can find such things in the system catalog

SELECT d.datname as "Name",
pg_catalog.pg_get_userbyid(d.datdba) as "Owner"
FROM pg_catalog.pg_database d
WHERE d.datname = 'database_name'
ORDER BY 1;

If you use the psql command-line tool, you can simply use \l

You can use the combination of pg_database, pg_users system tables and current_database() function in this way:

 SELECT u.usename 
 FROM pg_database d
  JOIN pg_user u ON (d.datdba = u.usesysid)
 WHERE d.datname = (SELECT current_database());

can just cast the role OID with magic ::regrole to give the role name of owner:

SELECT datdba::regrole FROM pg_database WHERE datname = 'test' ;

This work with database owned by group role:

SELECT
    U.rolname
   ,D.datname
FROM
    pg_roles AS U JOIN pg_database AS D ON (D.datdba = U.oid)
WHERE
    D.datname = current_database();

Using pg_authid (as I did in my previous version) instead of pg_roles is limited to SuperUser because it holds password (see documentation):

> Since this catalog contains passwords, it must not be publicly > readable. pg_roles is a publicly readable view on pg_authid that > blanks out the password field.

The follwing query displays info for all tables in the public schema:

 select t.table_name, t.table_type, c.relname, c.relowner, u.usename
 from information_schema.tables t
 join pg_catalog.pg_class c on (t.table_name = c.relname)
 join pg_catalog.pg_user u on (c.relowner = u.usesysid)
 where t.table_schema='public';

source :http://cully.biz/2013/12/11/postgresql-getting-the-owner-of-tables/

Remember in SQL including postgres that you have a heirarchy within a given sql server instance: catalog/db > schema > tables

When looking for perms/metadata for within a catalog you want to look at information_schema

Example: information_schema.role_table_grants for table perms

Example: information_schema.role_usage_grants for SEQUENCE/schema perms

https://www.postgresql.org/docs/current/information-schema.html

For catalog/db-level config/meta, you need to look another level up in pg_catalog.

https://www.postgresql.org/docs/current/catalogs.html

Example:

SELECT dbs.datname, roles.rolname
  FROM pg_catalog.pg_database dbs, pg_catalog.pg_roles roles
 WHERE dbs.datdba = roles.oid;

pg_catalog.pg_database.datdba has ID of owner role.

pg_catalog.pg_roles.oid has ID of owner role (join)

pg_catalog.pg_roles.rolname has name/string of owner role