pgTAP: Unit Testing for PostgreSQL

pgTAP is a suite of database functions that make it easy to write TAP-emitting unit tests in psql scripts or xUnit-style test functions. The TAP output is suitable for harvesting, analysis, and reporting by a TAP harness, such as those used in Perl applications.

Why would you want to unit test your database? Well, there are a couple of scenarios in which it can be useful.