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copying sqlite db to android device fails

I have an sqlite db which I copied to the 'asset' folder. In my prog I check if the database already exists, if not I create a new one and copy it. I used (more or less) the code from http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/comment-page-2/

    public void createDataBase() throws IOException {
    boolean dbExist = checkDataBase();

    if (dbExist) {
        Log.i(DEBUG_TAG, "createDataBase -> Datenbank existiert");
        // do nothing - database already exist
    } else {
        // By calling this method and empty database will be created into
        // the default system path
        // of your application so we are gonna be able to overwrite that
        // database with our database.
        this.getReadableDatabase();
        Log.i(DEBUG_TAG, "else, db existiert nicht 1");
        try {
            copyDataBase();
            Log.i(DEBUG_TAG, "nach copydatabase");
        } catch (IOException e) {
            throw new Error("Error copying database");
        }
    }
}

/**
 * Checked ob Database bereits existiert
 * 
 * @return
 */
private boolean checkDataBase() throws SQLiteException {
    SQLiteDatabase checkDB = null;
    Boolean checkTable = false;
    try {
        String myPath = DB_PATH + DB_NAME;
        checkDB = SQLiteDatabase.openDatabase(myPath, null,
                SQLiteDatabase.OPEN_READWRITE);
        Log.i(DEBUG_TAG, "checkdatabase1");

    } catch (SQLiteException e) {
        Log.e(DEBUG_TAG, "Fehler checkDataBase: ", e);
    }
    if (checkDB != null) {
        checkDB.close();
    }
    return checkDB != null ? true : false;
}

/**
 * Copies your database from your local assets-folder to the just created
 * empty database in the system folder, from where it can be accessed and
 * handled. This is done by transfering bytestream.
 * */
private void copyDataBase() throws IOException {
    // Open your local db as the input stream
    InputStream myInput = dbContext.getAssets().open(DB_NAME);

    // Path to the just created empty db
    String outFileName = DB_PATH + DB_NAME;

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

    // transfer bytes from the inputfile to the outputfile
    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();
    Log.i(DEBUG_TAG, "copydatabase");
}

In the Emulator it works perfectly fine.

I tried then to run it on my device (HTC Desire HD). There I get the following message:

03-26 17:02:05.053: INFO/Database(24458): sqlite returned: error code = 14, msg = cannot open file at line 27206 of [42537b6056]

This happens, when I try the first time to open the DB. When I run the Program in the emulator, I dont get this message. When I run the 开发者_C百科programm the 2nd time, it finds the database, no errors with opening, but the tables do not exist.

I've debugged the program on the emulator and the device several times, but could not find any solution.

Could this be some kind of permission problem? (Since I'm also not able to see the db on the device with adb --> permission denied')

I'm very new to android, so maybe I just missed something stupid....

Thanks


  1. Do not create paths via string concatenation. Use the appropriate File constructor.
  2. Your DB_PATH may be invalid, but since you declined to show it, we cannot say for certain.
  3. If the class that this code comes from is a SQLiteOpenHelper, your call to getReadableDatabase() will create an empty database.
  4. "(Since I'm also not able to see the db on the device with adb --> permission denied'" -- this is expected, as you do not have rights to view that directory on a production device.


I make it worked by creating my own directory and placing the File inside the Directory

String path=mContext.getDir("Folder_name", Context.MODE_WORLD_WRITEABLE).getAbsolutePath();

The Code to create the folder.

Then do our operation of checking the database and copying the database.

enter code here 

 public void createDataBase() throws IOException { 
 String path=mContext.getDir("Folder_Name", Context.MODE_WORLD_WRITEABLE).getAbsolutePath();
 DB_PATH=path;
 boolean mDataBaseExist = checkDataBase(); 
 if(!mDataBaseExist) 
 { 
   try  
    { 
     copyDataBase(); 
    }  
    catch (IOException mIOException)  
    { 
    Log.d("Exception",mIOException.getMessage());
    throw new Error("ErrorCopyingDataBase"); 
    } 
} 
}


private boolean checkDataBase() 
{ 
    Log.d(TAG, "In checkDataBase :::::"); 
    File dbFile = new File( DB_PATH+DATABASE_NAME); 
    Log.d("dbFile", dbFile + "   "+ dbFile.exists()); 
    return dbFile.exists(); 
} 

//Copy the database from assets 
private void copyDataBase() throws IOException 
{ 
    Log.d(TAG, "In copyDataBase :::::"); 
    InputStream mInput = mContext.getAssets().open(DB_NAME);
    String outFileName = DB_PATH  + DATABASE_NAME;

    Log.d(TAG, "In copyDataBase  outFileName:::::"+outFileName);

    OutputStream mOutput = new FileOutputStream(outFileName); 
    byte[] mBuffer = new byte[1024]; 
    int mLength; 
    while ((mLength = mInput.read(mBuffer))>0) 
    { 
        mOutput.write(mBuffer, 0, mLength); 
    } 
    mOutput.flush(); 
    mOutput.close(); 
    mInput.close(); 
} 

//Open the database, so we can query it 
public boolean openDataBase() throws SQLException 
{ 
    //DB_PATH +
    String mPath = DB_PATH+ DATABASE_NAME; 
    Log.v("mPath", mPath); 
    mDataBase = SQLiteDatabase.openDatabase(mPath, null, SQLiteDatabase.CREATE_IF_NECESSARY); 
    return mDataBase != null; 
} 

Hope this will help the new comers.

Cheers

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