How to unit test an SQL query?

Question

I have a class DBHandler which takes a query, runs it through the SQL server, checks for errors and returns the result. How can I unit test this class?

Answer 1

A quick solution for a mock db works like this:

• Setup an HSQLDB test server independent from your app.

• Populate with test data.

• Use conditional code where you connect to your real database, to connect to the test server. A property in your application can control this.

• Test the application