I am not all that sure, but you might mean MVC. Which stands for Model-View-Controler.

You can find more information on this web site.

Now to your question about the how-to. There Is More Than One Way To Do IT. I normally have a lot of predefined SQL strings with placeholders saved in strings, which I than feed to subs which do the work. I.e. One sub which Inserts, Updates, Deletes, and another sub which Selects.

You also might want to take a look at a rather un-academical guide to SQL.

/oliver/