Are Databases and Functional Programming at odds?

Question

I\'ve been a web developer for some time now, and have recently started learning some functional programming. Like others, I\'ve had some significant trouble apply many of

Answer 1

I don't think the stateless nature of fp languages is a problem with connecting to databases. Lisp is a non-pure functional programming language so it shouldn't have any problem dealing with state. And pure functional programming languages like Haskell have ways of dealing with input and output that can be applied to using databases.

From your question it seems like your main problem lies in finding a good way to abstract away the record-based data you get back from your database into something that is lisp-y (lisp-ish?) without having to write a lot of SQL code. This seems more like a problem with the tooling/libraries than a problem with the language paradigm. If you want to do pure FP maybe lisp isn't the right language for you. Common lisp seems more about integrating good ideas from oo, fp and other paradigms than about pure fp. Maybe you should be using Erlang or Haskell if you want to go the pure FP route.

I do think the 'pseudo-oo' ideas in lisp have their merit too. You might want to try them out. If they don't fit the way you want to work with your data you could try creating a layer on top of Weblocks that allows you to work with your data the way you want. This might be easier than writing everything yourself.

Disclaimer: I'm not a Lisp expert. I'm mostly interested in programming languages and have been playing with Lisp/CLOS, Scheme, Erlang, Python and a bit of Ruby. In daily programming life I'm still forced to use C#.