Philip Warner <pjw@rhyme.com.au> writes:
> I think the hierarchy goes:
> Environment->Catalog->Schema
> From what I can tell:
> 1. the environment contains truly general things like the SQL parser, the
> tools for connecting to the DB etc - which I assume also contains the
> user-authorization stuff.
In that case it would seem that environment maps to what we call an
installation --- if users are environment-wide then that's certainly
the natural mapping. Then database maps to catalog and schema is a
new feature within databases.
> 3. Schemas are what we call databases. They contain tables, views wtc.
Schemas are *not* databases, because (IIRC) it's possible for a single
session to access multiple schemas.
regards, tom lane