Create Postgres User with admin rights just for one database

Question

How can I create a postgres user who has admin access only to one database but cannot inspect or interfere with other databases in the postgres instance? The use case is I'm creating a multitenant application

• where each tenant gets his own database in the postgresql instance and can create schemas, tables etc and
• perhaps use a few pg_tables to inspect his own database but not others.
• cannot change the name of the database as it's controlled by me

EDIT: Added more constraints

Answer 1

That's fairly trivial:

CREATE DATABASE newdb;
GRANT CREATE ON DATABASE newdb TO newdba;

Add pg_hba.conf entries to allow newdba to connect to newdb only.