Question

At the moment I am fiddling myself into working with sql databases in android and created my first app. now i wanted to update this app and the including database in the assets folder. I overwrote the old database with the new one but on my phone it doesnt show the new entries.

It somehow is saving the old entries/queries or entirely the old Db. I checked on the net but couldnt really find a solution. Below my dbhelper code. Do i have to do something in onUpgrade or what would be the procedure?

Many thanks for helping!

public class DataBaseHelper extends SQLiteOpenHelper {
private static String DB_PATH;

private static String DB_NAME;

private SQLiteDatabase db_object;

private final Context context;

public DataBaseHelper(Context context, String db) {
    super(context, db, null, 80);
    this.context = context;
    DB_PATH = "/data/data/" + context.getPackageName() + "/databases/";
 //   DB_PATH = "/data/data/com.comp.appname/databases/";
    DB_NAME = "mydatabase.sqlite";
    try {
        createDataBase();
    } catch (IOException ioe) {
        throw new Error("Unable to create database");
    }
    try {
        openDataBase();
    } catch (SQLException sqle) {
        throw sqle;
    }
}

@Override
public void onCreate(SQLiteDatabase db) {
    // TODO Auto-generated method stub
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    // TODO Auto-generated method stub
}

public void createDataBase() throws IOException {
    boolean dbExist = checkDataBase();
    if (dbExist) {
    } else {
        this.getReadableDatabase();
        try {
            copyDataBase();
        } catch (IOException e) {
            throw new Error("Error copying database");
        }
    }
}

private boolean checkDataBase() {
    SQLiteDatabase checkDB = null;
    try {
        String myPath = DB_PATH + DB_NAME;
        checkDB = SQLiteDatabase.openDatabase(myPath, null,
                SQLiteDatabase.OPEN_READONLY);
    } catch (SQLiteException e) {
    }
    if (checkDB != null) {
        checkDB.close();
    }
    return checkDB != null ? true : false;
}

private void copyDataBase() throws IOException {
    InputStream myInput = context.getAssets().open(DB_NAME);
    String outFileName = DB_PATH + DB_NAME;
    OutputStream myOutput = new FileOutputStream(outFileName);
    byte[] buffer = new byte[1024];
    int length;
    while ((length = myInput.read(buffer)) > 0) {
        myOutput.write(buffer, 0, length);
    }
    myOutput.flush();
    myOutput.close();
    myInput.close();
}

public void openDataBase() throws SQLException {
    String myPath = DB_PATH + DB_NAME;
    db_object = SQLiteDatabase.openDatabase(myPath, null,
            SQLiteDatabase.OPEN_READONLY);
}

@Override
public synchronized void close() {
    if (db_object != null)
        db_object.close();
    super.close();
}
}

Answer 1

I solved my own problem:

in the onUpgrade method you need to put:

mycontext.deleteDatabase(DB_NAME);

in the databasehelper class i need to increase the version number like this for example:

super(context, db, null, 84); 

with mine it is 84 but basically you just need to increment it by 1, saying it is a higher version. Optimum would be if it exactly is your database version that you increment as well with every external edit of your db.

Hope that will help others.