Those "what ifs" had hit me in a few projects already. This is why spring-test module from Spring Framework is very helpful if you're doing Java projects. I do

Those "what ifs" had hit me in a few projects already. This is why spring-test module from Spring Framework is very helpful if you're doing Java projects. I don't have to deploy "war" to Tomcat or Jetty. I can mock the Request and Response object. We do have integration-tests that test specifically component that interact with databases. But there are another set of unit-tests that test the business/process workflow and assume the database will return something relevant. We do this because we want to write many tests with focus specifically to business/process workflow related code, not the database layer. This way we can write more tests without paying the taxes of: performance and setup (when you have a huge database models, it's not fun to prepare the models for each-single-unit-test that has to touch the database even though the purpose of that unit-test is not to test the database). So far this model has worked well for us (i.e.: no more excuses that build takes too long or writing unit-tests take too long due to the setup both infrastructure and preparing huge model).