Unit Testing TSQL

I went through a period of time where I spent a lot of effort figuring out how to set up unit tests for TSQL. It wasn’t easy. There are a few tools out there that help, but mostly it involves lots of programming. well, not as much as before. Thanks to the latest Down Tools Week at Red Gate a new utility has been built and released into the wild, SQL Test.

Like a lot of the new tools coming out of Red Gate these days, this one is directly integrated into SSMS, which means you’re working where you’re comfortable and where you already have lots of tools at your disposal. After the install, when you launch SSMS and get connected, you’re prompted to install the tSQLt example database. Go for it. It’s a quick way to see how the tool works. I’d suggest using it. It’ gives you a quick leg up.

The concepts are pretty straight forward. There are a series of CLR commands that you use to configure a test and the test assertions. In between you’re calling TSQL, either calls to your structure, queries, or stored procedures. They already have the one things that I always found wanting in database tests, a way to compare tables of results. I also like the ability to create a dummy copy of tables for the tests. It lets you control structures and behaviors so that the tests are more focused. One of the issues I always ran into with the other testing tools is that setting up the tests might require potentially destructive changes to the structure of the database (dropping FKs, etc.) which added lots of time and effort to setting up the tests, making testing more difficult, and therefor, less useful.

Functionally, this is pretty similar to the Visual Studio tests and TSQLUnit tests that I used to use. The primary improvement over the Visual Studio tests is that I’m working in SSMS instead of Visual Studio. The primary improvement over TSQLUnit is the SQL Test interface it self. A lot of the functionality is the same, but having a sweet little tool to manage & run the tests from makes a huge difference. Oh, and don’t worry. You can still run these tests directly from TSQL too, so automation has not gone away.

I’m still thinking about how I’d use this in a dev environment where I also had source control to fret. That might be another blog post right there. I’m just getting started with SQL Test, so this is the first of several blog posts & videos. Watch this space. Try the tool.