I wish I'd known about DBD::Mock sooner. I'm (painfully) creating bogus data and then deleting it in my existing test suites.

I do not wish to take anything away from the fine post by dragonchild, because it is good advice. DBD::Mock is a lightweight way to test your API, as he said. But, as he also said, "That should be a good start."

In other words, it is not the whole solution. You should still be testing the database itself, in some capacity. You want to make sure the connection works, the database is returning the right type of data, the table structure works as expected, etc. So once you get a nice suite of API tests with DBD::Mock, you are still probably going to end up creating bogus data and deleting it, in order to further test your application's database interaction.

Please do not think I'm saying DBD::Mock is pointless, though. It allows you (and your test suite) to narrow down where a problem lies. For example, if you are getting incorrect data from the live db test, but correct data from the DBD::Mock test, then you know there might be something wrong with the database. This type of troubleshooting information is extremely useful.