User Management

Coming from a MySQL background, the way PostgreSQL deals with users
seems whacked out to say the least. And that's where I'm having my
problem.

Now in my pg_hba.conf file I have;
local   all     password
local   chris   password        passwd

so when I go 'select * from pg_shadow' I see the root user I added with
'create user'. With this user I can log into any database and create any
database. Which is perfect. However, my problem comes in when I try
delegate access to different databases for different users. Say I want
the user 'joe' to have access to the database 'chris'. The way I tried
to do this is in the file 'passwd' I added;
joe:joepass

which is in the same directory as my pg_hba.conf. Not only does it seem
Postgres isn't reading this file, but how can I have 'joe' own the
database when a database is owned my whoever made it? Joe doesn't have
the ability to create databases because I only want joe to play with his
own database.

Needless to say I'm confused. I've scoured the online manuals, and the
PostgreSQL book is next to useless for indepth administration.

Any help, pointers, or links would be much appreciated,

Chris