Best method of identifying users from the db?

[Sykoi]

So...

PHP Code:

SELECT * from vb3_user WHERE userid=### AND password=md5(concat(md5(password),vb3_user.salt)) 


Is this correct? Or are you referring to php functions of md5/concat and not mysql (Is concat even in mysql...?)

And as for the extent at which I have access, I have complete access to the database but no access to the vB php files.

Also, while I have asked this before I'll ask again - is there any way to create a forum "blindly", as in outside the architecture? I looked at the forums table and its incredibly complex and requires some vB-only generated things.