So I'm further along in building my app and am construction complex sql queries. Using trial'n'error is getting cumbersome here. Is there any better way? I'm mostly developing on iOS...
You tagged your question AppConKit, so I'll assume you need help there. When you are developing iOS Apps with the AppConKit, an SQLite Database is automatically created on the device.
You can easily copy the current SQLite database from your device. To be sure your latest data changes are stored to the database file, close your app. Connect your device to your Mac/PC and open iTunes. In iTunes go to your device and click the Apps tab. On the File Sharing section select the AppConClient. Here's a file named ibizclient.sqlite which you can save with the save button above. With a free SQLite viewer you can open the database and check what you want to know.
Windows SQLite viewer: SQLiteSpy
Mac SQLite viewer: SQLiteManager