title: Distinquish between 0 and some datasets from db (both valid cases)
body: <p>currently I'm using phpunit to write tests for some functions that access a mysql-database. Now I'm unsure what to do to distinguish when a function returns some datasets or nothing (which both are valid function results). Should I use different tests (so that one of them will fail in any case) or is it in this case ok to use an if that possibly skips asserts? I have to do some tests on the results, if there are some.</p>
  
  <p>I know this has been asked before somewhere already, but I couldn't formulate a proper query to get me an answer, sorry.</p>