Re: which database to login to to create global users?

pres <pgn(dot)lists(at)gmail(dot)com> writes:
> so, if i understand you correctly, it does not matter which database i'm
> logged into when i create a role?

Correct.

> where (what database/table), then, are theses assignments stored?

The info related to roles is stored in some "shared" catalogs that are
visible in every database --- just the same way that pg_database is
visible in every database. Try this to see which catalogs are shared:

select relname from pg_class where relisshared and relkind = 'r';

See also the documentation on the system catalogs:
http://www.postgresql.org/docs/8.1/static/catalogs.html
The description of each catalog takes care to mention it if the catalog
is shared across databases.

regards, tom lane