User Authentication and Sessions? + Questions on Postgre vs MySQL

[eluser]Aea[/eluser]
Thank you Rick Jolly, that is what I expected. Is there any consensus no which is better? OB Session seems to be the premier choice since it just stores the session_id is stored in the cookie and everything else in the database, need to do some research since $_SESSION is something that I absolutely must be able to use both for this project and further ones.

As for Question 3, I have a large amount of static data which I need to be referenced on a lot of pages and scripts, so instead of pulling it from the database I wondered if it would be more efficient to store it all in one array, but somehow have that array be shared across all users (instead of being redeclared, and such) it seems like quite the awkward question since I can't really verbalize the idea well.