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Android Android Data Persistence Migrating a SQLite Database Adding a New Field

Ben Wong
Ben Wong
19,426 Points

We are going to release a new version that allows users to select a home planet as well. Migrating a SQLite Database.

Need help! Stuck:(

public class AlienSQLiteHelper extends SQLiteOpenHelper {

public static final String DB_NAME = "aliens.db"; public static final int DB_VERSION = 1;

public static final String ALIENS_TABLE = "ALIENS"; public static final String COLUMN_NAME = "NAME"; public static final String COLUMN_TYPE = "TYPE";

public static final String CREATE_ALIENS = "CREATE TABLE " + ALIENS_TABLE + " (" + "_id INTEGER PRIMARY KEY AUTOINCREMENT," + COLUMN_NAME + " TEXT, " + COLUMN_TYPE + " TEXT)";

public static final String DB_ALTER = "ALTER TABLE " + ALIENS_TABLE + " ADD COLUMN ";

public AlienSQLiteHelper(Context context) { super(context, DB_NAME, null, DB_VERSION); }

@Override public void onCreate(SQLiteDatabase sqLiteDatabase) { sqLiteDatabase.execSQL(CREATE_ALIENS); }

@Override public void onUpgrade(SQLiteDatabase database, int oldVersion, int newVersion) { switch (oldVersion) { case 1: sqLiteDatabase.execSQL(DB_ALTER);

}

} }

AlienSQLiteHelper.java
public class AlienSQLiteHelper extends SQLiteOpenHelper {

  public static final String DB_NAME = "aliens.db";
  public static final int DB_VERSION = 1;

  public static final String ALIENS_TABLE = "ALIENS";
  public static final String COLUMN_NAME = "NAME";
  public static final String COLUMN_TYPE = "TYPE";

  public static final String CREATE_ALIENS = "CREATE TABLE " + ALIENS_TABLE + " (" +
          "_id INTEGER PRIMARY KEY AUTOINCREMENT," +
          COLUMN_NAME + " TEXT, " +
          COLUMN_TYPE + " TEXT)";

  public static final String DB_ALTER = "ALTER TABLE " + ALIENS_TABLE + " ADD COLUMN ";

  public AlienSQLiteHelper(Context context) {
    super(context, DB_NAME, null, DB_VERSION);
  }

  @Override
  public void onCreate(SQLiteDatabase sqLiteDatabase) {
    sqLiteDatabase.execSQL(CREATE_ALIENS);
  }

  @Override
  public void onUpgrade(SQLiteDatabase database, int oldVersion, int newVersion) {
    switch (oldVersion) {
      case 1:
     sqLiteDatabase.execSQL(DB_ALTER);

    }
  }
}

3 Answers

George Pirchalaishvili
George Pirchalaishvili
3,747 Points

If you are stuck on 1st part, than you should just change the DB_VERSION = 1; to 2.

Ben Wong
Ben Wong
19,426 Points

Got it George. Much Appreciated it!

Just that thanks very much,got it too