Question

I’ve followed the instructions given here for introducing an existing SQLite database to your Android app.

When I query the table “android_metadata” this is fine. But when I run a similar query on my own table “words” (which has _id for primary integer key) I get a table does not exist exception and the app crashes.

Why is that?

Code:

Cursor c = myDatabase.query("android_metadata", null, null, null, null, null, null, null);

works but

Cursor c = myDatabase.query("words", null, null, null, null, null, null, null);

returns a table does not exist exception.

This is how I’m creating the database (the references to paths and filenames are correct):

private void copyDatabase() throws IOException
{
    //Open local db as the input stream
    InputStream myInput = mContext.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 = 0;
    while ((length = myInput.read(buffer))>0){
        myOutput.write(buffer, 0, length);
    }

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

(Note: To my eyes, the table is there. I’m looking right at it in my SQLite browser.)

Answer 1

You’re following a red herring. The android_metadata table is created in every android database no matter what.

The real mechanism for determining your issue is to simply run your app in the emulator and check out the database. If your emulator is running and the application has setup the database, run:

adb shell
cd /data/data/your.application.package/databases
ls

if ls shows the database name you expect, run:

sqlite3 <your db file>

at the sqlite3 prompt run : .schema

This will print out the tables of the databases. My guess is that you’ll find just the meta data table because android is not actually reading your database from your external location. If thats the case, comment back and I can try to help you through that process.