Take a look at Test::MockObject. What you are trying to test is the script, not the database, therefore you can fake the database (and its date and dayofweek functions) using MockObjects.

Do a super search on Test::MockObject to see some other uses of mocking. It is a very powerful technique that allows you to concentrate on the main job of your code, and it allows you to keep testdata and tests in the same place.

Good luck!