Android sqlite update table always return 0

SQLiteDatabase.update() returns number of rows affected. So, in your case, no rows were affected (most probably because of your WHERE clause)

It sounds like nothing matches your criteria. Perhaps as a test you should pass null as your where criteria (this signifies update all rows) and see if 0 is still returned.

If 0 is still returned after that I would look to ensure you actually have data saved in your database table.