public String getData(int i) {
    StringBuffer buffer = new StringBuffer();
    db = this.getReadableDatabase();
    Cursor res = db.rawQuery("SELECT * FROM " + TABLE_NAME + " WHERE " + COLUMN_ID + " = "+ i, null);
    while (res.moveToNext()) {
        String firstname = res.getString(1);
        String lastname = res.getString(2);
        buffer.append(firstname);
        buffer.append(" ");
        buffer.append(lastname);
    }

    return buffer.toString();

}

public class WidgetProvider extends AppWidgetProvider {

DatabaseHandler myDb;


@Override
public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
    for (int appWidgetId : appWidgetIds) {
        Intent intent = new Intent(context, MainActivity.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);

        RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.widget_layout);
        views.setOnClickPendingIntent(R.id.button, pendingIntent);
        views.setCharSequence(R.id.button, "setText", myDb.getData(1));
        appWidgetManager.updateAppWidget(appWidgetId,views);
    }
}