Um, because that's crazy?
First, "session management" on a web site has nearly nothing
whatsoever to do with database accounts in Oracle, they're largely
orthogonal concepts.
Second, say you wanted to give every single registered user his own
Oracle account. openacs.org currently has 7,897 registered users.
Some sites using OpenACS have 50,000+ registered users. I really,
really doubt that Oracle accounts are designed for that. It
probably wouldn't work, and even if it did, AFAICT there's no
advantage whatsoever to doing it.
Oracle programmers sometimes talk about an Oracle "schema" when they
mean an Oracle "user", because there is usually a one to one
correspondance between the two. So if in doubt, substitute the word
"schema" anywhere you see Oracle "user" or "account" and think about
it that way. Does every individual user of a website need to define
separate relational tables in his own database schema? No, of course
not.
And while Oracle does have database accounts, I think PostgreSQL has
no such thing, anyway.
David, I suggest you take a step back, and tell us about what problem
you're actually trying to solve or understand, why you think "session
management" is related to it, etc.
