Scalar UDF inlining in SQL Server 2019 – FROID’s complex

This page contains the description for my conference session “Scalar UDF inlining in SQL Server 2019 – FROID’s complex”, and links to the slide deck and demo code used in this presentation.


Target audience Experienced database developers and DBAs.
Short description SQL Server 2019 brings FROID – inlining scalar user-defined functions. In this session we’ll lift the cover and investigate EXACTLY how this works.
Duration The ideal length for this session is 60 – 75 minutes.
Full abstract For many years, scalar user-defined functions have been the bane of SQL Server performance. Encapsulating and reusing logic was possible, but at a terrible price. Scalar UDFs are widely known for their devastating effect on performance.


In SQL Server 2019, Microsoft finally addresses this problem. As part of the “Intelligent Query Processing” family of features, a framework called “FROID” is introduced that automatically and transparently rewrites user-defined functions to a form that allows them to be inlined in the query. And this allows the query optimizer to make these queries suddenly much faster!


Come to this session if you want to learn how this works. You will see a complete explanation of the steps SQL Server takes to enable this new functionality, Illustrated with several examples – starting simple and eventually building towards more complexity.


This session has not yet been presented. I am still working on the slide deck and the demos, and will probably continue to do so until shortly before it is first presented. The “final” version of the slide deck and demo code will be uploaded here around the time I first deliver this session.

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.