Often you need to create extra database data to run your PHPUnit test, when you're creating your application with Yii2 framework. The best is, that you're doing this work only once and save this with your test, so that you can re-use this test data on every test run. This data is called "fixtures". I want to introduce you my approach of using fixtures with CSV files, which are containing the data which will be written into your database, as you're fireing your PHPUnit test. For programming and running PHPUnit tests I prefer PhpStorm. But you can test your code also with PHPUnit by command line of some configuration in Netbeans or Eclipse with PHP configuration.
PhpMyAdmin and MySQL workbench are allowing you to export CSV files with your database data and the column-names in the first line of the export. The contents of the first line are the names of your properties, which are defined in your Yii model. Ok, let's say you have such exports, you need to have your PHPUnit test.