SQLiteException: no such table... Android

I'm suffering with a trouble concerning Android.

Here is the tuto I followed: http://ift.tt/1QbECRd

I tried differents fixes but nothing is working. Whenever I'm trying to query my database I got this error: SQLiteException: no such table...

I stored my database file in the following repository: /src/main/assets This file is a SQL script ( creation of the tables and insert of some values ) with the .db format.

What is wrong? I still don't know why it's not working. My code is almost the same than on the link I gave you. Thanks in advance.