Hello @Martin_Thomas_Mathew,
You are right that the data has been changed some time ago. Now we have something like this:
Consequently, the maths in my earlier post has to change to this:
For example, if a user rated 3 movies and each movie has 3 genres associated, then you will end up seeing 1 (user) x 3 (movies) = 3 rows of data in both the user and the item data tables, and because all these 3 rows belong to the same user, you will see 3 identical user rows in the user table, and in the corresponding item table rows, you will see 3 movie ids.
Thank you, @Martin_Thomas_Mathew, for bringing this up so that I can clarify it.
Cheers,
Raymond