in reply to
MySQL, MS SQL, PostgreSQL - Common interface
Well, I'd say if you're going to abstract from SQL up, abstract the whole way to an OO-View where you don't use SQL itself anymore - but if you are determined to write such a module - which could be very useful indeed - I suggest to take a look at the SQLFairy (SQL::Translator) - they have done such a thing already - you could use SQL::Translator on-the-fly, or at least prey upon it to reuse their effort.
An intellectual is someone whose mind watches itself.
-- Albert Camus