DatabaseHelper.class

public class DatabaseHelper extends SQLiteOpenHelper{
    //Constants for db name and version
    private static final String DATABASE_NAME = "todos.db";
    private static final int DATABASE_VERSION = 1;


    //SQL to create tables
    private static final String TABLE_CATEGORIES_CREATE=
            "CREATE TABLE " + CategoriesEntry.TABLE_NAME + " (" +
                    CategoriesEntry._ID + " INTEGER PRIMARY KEY, " +
                    CategoriesEntry.COLUMN_DESCRIPTION + " TEXT " +
                    ")";
    private static final String TABLE_TODOS_CREATE =
            "CREATE TABLE " + TodosEntry.TABLE_NAME + " (" +
                    TodosEntry._ID + " INTEGER PRIMARY KEY, " +
                    TodosEntry.COLUMN_TEXT + " TEXT, " +
                    TodosEntry.COLUMN_CREATED + " TEXT default CURRENT_TIMESTAMP, " +
                    TodosEntry.COLUMN_EXPIRED + " TEXT, " +
                    TodosEntry.COLUMN_DONE + " INTEGER, " +
                    TodosEntry.COLUMN_CATEGORY + " INTEGER, " +
                    " FOREIGN KEY("+ TodosEntry.COLUMN_CATEGORY + ") REFERENCES " + CategoriesEntry.TABLE_NAME
                    + "(" + CategoriesEntry._ID +") " + ")";


    public DatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(TABLE_CATEGORIES_CREATE);
        db.execSQL(TABLE_TODOS_CREATE);
        //seed(db);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("DROP TABLE IF EXISTS " + TodosEntry.TABLE_NAME);
        db.execSQL("DROP TABLE IF EXISTS " + CategoriesEntry.TABLE_NAME);
        onCreate(db);
    }