mi aplicación experimenta un bloqueo cuando la base de datos sqlite se actualiza la primera vez. Recargando la aplicación, funciona bien a partir de entonces. Supongo que esto tiene que ver con la función onUpgrade entonces. Parece que no puedo localizar dónde está el problema, algún consejo muy apreciado. Gracias por adelantado.

Base de datosHelper:

public class DatabaseHelper extends SQLiteOpenHelper {

    private static String DB_PATH = "/data/data/jp.atomicideas.ne/databases/";
    private static String DB_NAME = "dataset";
    public static final int DB_VERSION = 2;
    private SQLiteDatabase myDataBase;
    private final Context myContext;
    public static final String EXPRESSION_TABLE = "expression";

    /**
     * Constructor
     * Takes and keeps a reference of the passed context in order to access
     * the assets and resources.
     * 
     * @param context
    */
    public DatabaseHelper(Context context) {
        super(context, DB_NAME, null, DB_VERSION);
        this.myContext = context;
    }

    /**
     * Creates an empty database on the system and rewrites with database from app
     * @throws IOException
    */
    public void createDataBase() throws IOException {
        boolean dbExist = checkDataBase();  
        // if the database already exists, do nothing
        if(dbExist){
            Log.v("DB Exists", "db exists");
            // by calling this method here, onUpgrade will be called on a writeable db, if version number is bumped
            this.getWritableDatabase();
        } 
        dbExist = checkDataBase();
        // if the database doesn't exist, copy the application's database to be used
        if(!dbExist) {
            this.getReadableDatabase();
            try {
                copyDataBase();
            } catch (IOException e) {
                throw new Error("Error copying database");
            }
        }
    }

    /**
     * Check if the database already exists to avoid re-copying the file
     * @return true only if it exists, falls if it doesnt
    */
    private boolean checkDataBase() {
        SQLiteDatabase checkDB = null;

        try {
            String mypath = DB_PATH + DB_NAME;
            checkDB = SQLiteDatabase.openDatabase(mypath, null, SQLiteDatabase.OPEN_READONLY);
        } catch(SQLiteException e) {
            // database does not exist yet
        }

        if(checkDB != null) {
            checkDB.close();
        }

        return checkDB != null ? true : false;
    }

    /**
     * Copies database from the local assets folder to the system folder
     * @throws IOException
    */
    private void copyDataBase() throws IOException {

        // Open the app database file as the input stream
        InputStream myInput = myContext.getAssets().open(DB_NAME);

        // Path to the empty temporary database to be replaced
        String outFileName = DB_PATH + DB_NAME;

        // Open the empty database file as the output stream
        OutputStream myOutput = new FileOutputStream(outFileName);

        // Transfer bytes from the input file to the output file
        byte[] buffer = new byte[1024];
        int length;
        while ((length = myInput.read(buffer)) > 0) {
            myOutput.write(buffer, 0, length);
        }

        // Close the streams
        myOutput.flush();
        myOutput.close();
        myInput.close();

    }

    public void openDataBase() throws SQLException {

        // Open the database
        String myPath = DB_PATH + DB_NAME;
        myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
    }

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

    @Override
    public void onCreate(SQLiteDatabase db) {

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

        Toast.makeText(myContext, "onUpgrade called!", Toast.LENGTH_LONG).show();

        if (oldVersion < newVersion) {
            Log.v("Database Upgrade", "Database version higher, upgrading");
            myContext.deleteDatabase(DB_NAME);                          
        }
    }

}

Y aquí está la salida de LogCat:

06-28 20:52:07.638: V/DB Exists(26580): db exists
06-28 20:52:07.658: V/Database Upgrade(26580): Database version higher, upgrading
06-28 20:52:07.658: I/Database(26580): sqlite returned: error code = 1802, msg = statement aborts at 3: [PRAGMA user_version = 2] 
06-28 20:52:07.658: E/Database(26580): Failure 10 (disk I/O error) on 0x33a3f0 when executing 'PRAGMA user_version = 2'
06-28 20:52:07.658: I/Database(26580): sqlite returned: error code = 1, msg = statement aborts at 2: [ROLLBACK;] cannot rollback - no transaction is active
06-28 20:52:07.658: E/Database(26580): Failure 1 (cannot rollback - no transaction is active) on 0x33a3f0 when executing 'ROLLBACK;'
06-28 20:52:07.658: D/Database(26580): exception during rollback, maybe the DB previously performed an auto-rollback
06-28 20:52:07.668: D/AndroidRuntime(26580): Shutting down VM
06-28 20:52:07.668: W/dalvikvm(26580): threadid=1: thread exiting with uncaught exception (group=0x2aac8578)

Y

06-28 20:52:07.678: E/AndroidRuntime(26580): Caused by: android.database.sqlite.SQLiteDiskIOException: disk I/O error: PRAGMA user_version = 2