Scalar user defined functions seem like a great idea, you can put a bunch of code into a nice neat little package and call it from wherever you want. You do it and it runs great on your development environment so you deploy it. It's only then that users start complaining about poor performance, what do you do next?

In this session we'll cover why scalar functions don't scale well and what we can do about replacing them. We'll cover
- Row vs Set based logic
- How scalar functions don't scale
- Parallel vs Serial plans
- Why SET STATISTICS doesn't give the whole picture

There are a number of things we can do to get around this problem, we'll go through these and compare the performance of each.

We'll be using the Stack Overflow database and the scripts will be provided in advance of the session so you can follow along with the presentation.