Permissions Scenerio

Hello list,

I've been a PostGres user for a while, but am just now having to implement some security for a project. The hope is that we can create an environment through Roles that would allow users the ability to create a database(s) and have access to their database(s) but not have access to others' databases. I've been able to get part of the way there to create a user with createDB privileges and recording them in the pg_hba.conf file. However, when my test user creates a new database, they are the owner of that database but can't use it. Is there a way to avoid having to add user /database entry in
the pg_hba.conf file every time a user creates a new database?

Here is the current hba conf file I have

host all postgres 127.0.0.1/32 md5 # Super user admin account
host samerole testuser 127.0.0.1/32 md5
host template_db all 127.0.0.1/32 md5

Under this conf file my testuser can create a new db, but then doesn't have access to it b/c no entry exsists in the conf file.

This is probably an easy change but being new to PostGres security I'm not seeing it.

If I can't do this with Roles, can I do it with schemas to give users only access to their own stuff within a database?

Thanks in advance for any guidance

- Trent