In a new post to his blog Brian Swan compares the database drivers for MSSQL and SQLSRV by what they have to offer and what the real differences are to your applications.

In this post I want to begin looking at some of the differences between the two drivers and perhaps gain an understanding of why the mssql driver continues to be used (although I have some good guesses). There are lots of comparison points between the mssql and sqlsrv drivers. I’ll break my comparison into two posts, focusing on high-level differences in this post and then dive into an API comparison in the next post.

This first of the two parts looks at some of the differences between the two - the Microsoft support for the sqlsrv driver vs community-driven mssql and the fact that they're very different "under the hood" (see this diagram).