unit testing with rollback on database

Question

I'm just starting to understand the importance of Unit Testing in a c# environment. Now, I'm wondering how do i implement a black-box unit test that does Inserts,Deletes and updates on a database and then cleaning up the data after a successful test.

How do you actually do a process that rollbacks data inserted/updated/deleted? do you simply reset the index and remove the inserted rows? or restore the original state of the table by creating a script?

please guide me, I appreciate it. thanks!

Answer 1

What we do here in our development cycle. we always have that unit testing and load testing in our mind when ever we are developing application. So we make a column in our every datadase's table with userId or else. Then when we run Load Test or Unit test we insert UserId -1 in that every column, pointing that it is a load test data and -2 in case of unit Test Data. then we have pre Define Jobs at data base end that will clean that data after some time.

Answer 2

As long as your test is concise, and i presume it must be - for testing your DAL, why not just do the insert / update / deletes in a transaction that is rolled back once your test is complete.

Another option is to just use specific Update / Delete scripts in your test cleanup methods to roll back the exact changes that you updated / inserted to their pre-test values.

Answer 3

I think deleting the rows in the CleanUp method should be good choice.

By this you will always be testing your deleting rows code.

Answer 4

One option is to use a Mock database in place of a real database. Here's a link that describes it.