Where Room save database Android?

in Android Studio there is a section called "Device File Explorer", at the bottom right. In this section you can explore all the files (which you can not see in a simple file explorer app because you need to run the root).

Make sure the emulator is the one you're working with. In this explorer you have to go to "data" -> "data", look for the package name of your app and the next step is to find "database" entry, in this folder there is your Room database.

static final String DATABASE_NAME = "photex_db";

Here, you are trying to open photoex_db.

String currentDBPath=getDatabasePath("photex_db.db").getAbsolutePath();

Here, you are trying to read from photex_db.db.

These are not the same.

You might consider using DATABASE_NAME consistently, rather than only in some places.

Try out this code :

String backupDBPath = YourRoomDatabase.getDatabase(context).getOpenHelper().getWritableDatabase().getPath();

It will return the path of your database. Use this exact path to create the file where you want to copy it. It will definitely work as worked for me.

File backupDB = new File(backupDBPath);

There was a little mistake in my code ,after correcting its working fine

private void copyFile() {
    try {
        File sd = Environment.getExternalStorageDirectory();
        File data = Environment.getDataDirectory();

        if (sd.canWrite()) {
            String currentDBPath =
                    getDatabasePath("photex_db").getAbsolutePath();
            String backupDBPath = "photex_db.db";
            //previous wrong  code  
            // **File currentDB = new File(data,currentDBPath);**
            // correct code
            File currentDB = new File(currentDBPath);
            File backupDB = new File(sd, backupDBPath);

            if (currentDB.exists()) {
                FileChannel src = new FileInputStream(currentDB).getChannel();
                FileChannel dst = new FileOutputStream(backupDB).getChannel();
                dst.transferFrom(src, 0, src.size());
                src.close();
                dst.close();
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
}