What is pg_database_owner in Postgres

PostgreSQL 14 (released September 30, 2021) introduced a powerful predefined role: pg_database_owner. This role changes how database ownership and privileges are managed by providing a dynamic way to handle permissions for database owners.

What is `pg_database_owner`?#

pg_database_owner is a built-in role that automatically maps to the owner of the current database.

You don’t grant it to users.
Membership is implicit and context-dependent — whoever owns the database is the member.

This allows privileges granted to pg_database_owner in template databases to carry over automatically when new databases are created from them.

Why it Exists#

Two main problems it solves:

Template Database Privileges Before, ensuring consistent privileges across databases required manual grants. Now, you can grant to pg_database_owner in a template, and new DBs automatically apply them.
Safer Defaults Starting in PostgreSQL 15, the public schema is owned by pg_database_owner. This gives each DB owner direct control over schema access, fixing the long-standing risk of overly permissive defaults.

Key Characteristics#

Property	Description
Implicit membership	Always maps to the database owner
Database scope	Valid only in the current database
No login	Cannot log in directly
No explicit members	You cannot `GRANT ... TO pg_database_owner`
Template inheritance	Privileges granted in a template DB carry over
Isolation	Cannot be part of role hierarchies
Public schema ownership (v15+)	Owns the `public` schema

Common Error#

Trying to grant it explicitly produces an error:

GRANT pg_database_owner TO my_user;
ERROR: role "pg_database_owner" cannot have explicit members

✅ Correct usage:

Grant privileges to pg_database_owner
Or transfer DB ownership if you want a new effective owner

ALTER DATABASE mydb OWNER TO new_owner;

Practical Examples#

Schema Privileges

GRANT USAGE, CREATE ON SCHEMA app TO pg_database_owner;
ALTER DEFAULT PRIVILEGES IN SCHEMA app
  GRANT SELECT, INSERT, UPDATE, DELETE ON TABLES TO pg_database_owner;

Template Setup Grant monitoring or utility functions to pg_database_owner in a template DB so every new database owner gets access automatically.

Best Practices#

Do:

Use it in template DBs for consistent privileges
Grant privileges to it, not users
Leverage it for schema or function access

Don’t:

Try to grant it to users (will fail)
Expect cross-database scope
Assume it has privileges by default

Conclusion#

pg_database_owner is a small but important change: it gives PostgreSQL a clean, dynamic way to handle database ownership and privilege inheritance. Whether you’re building multi-tenant apps or just want safer defaults, it simplifies privilege management and improves security.

What is pg_database_owner in Postgres