Do Postgres Roles carry over from Databases if Databases are in the same server?

Question

If I am creating a new Database on the same hostname/server, Will the roles/users carry over? Or will I have to create them again with new names and passwords?

I see roles/users listed as server objects, rather than database specific.enter image description here

So I'm not sure if they will carry over to a new DB. Both DBs share the same server/host.

Follow up Question: If I already have roles created across the server. And they currently have read_only access on certain schemas in Database A.

If I want to grant them access to create, insert, update etc permissions on schemas in DataBase B. I would just need to say: GRANT SELECT, INSERT, UPDATE, DELETE ON ALL TABLES IN SCHEMA schema1 in Database B TO role1?

This wouldn't affect their privileges in Database A, correct? Is it considered good practice for role1 to have readonly access in Database A and and create access in Database B?

• jjanes: When you say "server", do you mean machine/host, or do you mean database server/database instance? If you create a new database "cluster" on the same machine, they do not carry over. If you create a new database on the same cluster, they do carry over.
• user16573033: To clarify, When I said host, I meant hostname. I have a host called: db-host-1.abc.io. This also correlates to my RDS instance. Both Database A and B connect to this host.

Answer 1

Quote from the manual

Database roles are global across a database cluster installation (and not per individual database). To create a role use the CREATE ROLE SQL command:

So, yes. Roles "carry over to a new database".

However, privileges are stored per object (table, view, sequence, database, ...). So the privileges for a table named person in the database one for a user arthur might be completely different than the privileges for that user for a table with the same name in a database named two

• user16573033: So If I already have roles created across the server. And they currently have read_only access on certain schemas in Database A. and I want to grant them access to create, insert, update etc permissions on schemas in DataBase B. I would just need to say: GRANT SELECT, INSERT, UPDATE, DELETE ON ALL TABLES IN SCHEMA schema1 in Database B TO role1? This wouldn't affect their privileges in Database A, correct? Is it considered good practice for role1 to have readonly access in Database A and and create access in Database B?