Simple export and import of a SQLite database on Android

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I am trying to implement a simple SQLite export/import for backup purposes. Export is just a matter of storing a copy of the raw current.db file. What I want to do for import is to just delete the old current.db file and rename the imported.db file to current.db. Is this possible? When I try this solution, I get the following error:

06-30 13:33:38.831: ERROR/SQLiteOpenHelper(23570):
    android.database.sqlite.SQLiteDatabaseCorruptException: error code 11: database disk image is malformed

If I look at the raw database file in a SQLite browser it looks fine.

5 Answers

To export db rather it is SQLITE or ROOM:

Firstly, add this permission in AndroidManifest.xml file:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

Secondly, we drive to code the db functions:

private void exportDB() {
    try {
        File dbFile = new File(this.getDatabasePath(DATABASE_NAME).getAbsolutePath());
        FileInputStream fis = new FileInputStream(dbFile);

        String outFileName = DirectoryName + File.separator +
                DATABASE_NAME + ".db";

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

        // Transfer bytes from the inputfile to the outputfile
        byte[] buffer = new byte[1024];
        int length;
        while ((length = fis.read(buffer)) > 0) {
            output.write(buffer, 0, length);
        }
        // Close the streams
        output.flush();
        output.close();
        fis.close();


    } catch (IOException e) {
        Log.e("dbBackup:", e.getMessage());
    }
}

Create Folder on Daily basis with name of folder is Current date:

public void createBackup() {

    sharedPref = getSharedPreferences("dbBackUp", MODE_PRIVATE);
    editor = sharedPref.edit();

    String dt = sharedPref.getString("dt", new SimpleDateFormat("dd-MM-yy").format(new Date()));

    if (dt != new SimpleDateFormat("dd-MM-yy").format(new Date())) {
        editor.putString("dt", new SimpleDateFormat("dd-MM-yy").format(new Date()));

        editor.commit();
    }

    File folder = new File(Environment.getExternalStorageDirectory() + File.separator + "BackupDBs");
    boolean success = true;
    if (!folder.exists()) {
        success = folder.mkdirs();
    }
    if (success) {

        DirectoryName = folder.getPath() + File.separator + sharedPref.getString("dt", "");
        folder = new File(DirectoryName);
        if (!folder.exists()) {
            success = folder.mkdirs();
        }
        if (success) {
            exportDB();
        }
    } else {
        Toast.makeText(this, "Not create folder", Toast.LENGTH_SHORT).show();
    }

}

Assign the DATABASE_NAME without .db extension and its data type is string

Import and Export of a SQLite database on Android

Here is my function for export database into device storage

private void exportDB(){
    String DatabaseName = "Sycrypter.db";
    File sd = Environment.getExternalStorageDirectory();
    File data = Environment.getDataDirectory();
    FileChannel source=null;
    FileChannel destination=null;
    String currentDBPath = "/data/"+ "com.synnlabz.sycryptr" +"/databases/"+DatabaseName ;
    String backupDBPath = SAMPLE_DB_NAME;
    File currentDB = new File(data, currentDBPath);
    File backupDB = new File(sd, backupDBPath);
    try {
        source = new FileInputStream(currentDB).getChannel();
        destination = new FileOutputStream(backupDB).getChannel();
        destination.transferFrom(source, 0, source.size());
        source.close();
        destination.close();
        Toast.makeText(this, "Your Database is Exported !!", Toast.LENGTH_LONG).show();
    } catch(IOException e) {
        e.printStackTrace();
    }
}

Here is my function for import database from device storage into android application

private void importDB(){
    String dir=Environment.getExternalStorageDirectory().getAbsolutePath();
    File sd = new File(dir);
    File data = Environment.getDataDirectory();
    FileChannel source = null;
    FileChannel destination = null;
    String backupDBPath = "/data/com.synnlabz.sycryptr/databases/Sycrypter.db";
    String currentDBPath = "Sycrypter.db";
    File currentDB = new File(sd, currentDBPath);
    File backupDB = new File(data, backupDBPath);

    try {
        source = new FileInputStream(currentDB).getChannel();
        destination = new FileOutputStream(backupDB).getChannel();
        destination.transferFrom(source, 0, source.size());
        source.close();
        destination.close();
        Toast.makeText(this, "Your Database is Imported !!", Toast.LENGTH_SHORT).show();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

If you want this in kotlin . And perfectly working

 private fun exportDbFile() {

    try {

        //Existing DB Path
        val DB_PATH = "/data/packagename/databases/mydb.db"
        val DATA_DIRECTORY = Environment.getDataDirectory()
        val INITIAL_DB_PATH = File(DATA_DIRECTORY, DB_PATH)

        //COPY DB PATH
        val EXTERNAL_DIRECTORY: File = Environment.getExternalStorageDirectory()
        val COPY_DB = "/mynewfolder/mydb.db"
        val COPY_DB_PATH = File(EXTERNAL_DIRECTORY, COPY_DB)

        File(COPY_DB_PATH.parent!!).mkdirs()
        val srcChannel = FileInputStream(INITIAL_DB_PATH).channel

        val dstChannel = FileOutputStream(COPY_DB_PATH).channel
        dstChannel.transferFrom(srcChannel,0,srcChannel.size())
        srcChannel.close()
        dstChannel.close()

    } catch (excep: Exception) {
        Toast.makeText(this,"ERROR IN COPY $excep",Toast.LENGTH_LONG).show()
        Log.e("FILECOPYERROR>>>>",excep.toString())
        excep.printStackTrace()
    }

}
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