The Android SQLite API

There are a number of different ways in which the Android API makes it fairly easy to use our app's database. The first class we need to get familiar with is SQLiteOpenHelper.

SQLiteOpenHelper and SQLiteDatabase

The SQLiteDatabase class is the class that represents the actual database. The SQLiteOpenHelper class, however, is where most of the action takes place. This class will enable us to get access to a database and initialize an instance of SQLiteDatabase.

In addition, the SQLiteOpenHelper class, which we will inherit from in our Age database app, has two functions to override. First, it has an onCreate function, which is called the first time a database is used, and it therefore makes sense that we would incorporate our SQL in which to create our table structure.

The other function we must override is onUpgrade, which, you can probably guess, is called when we upgrade our database (ALTER its structure).

Building and executing queries

As our database structures...