>I still do not understand how do you get # of users from your query when it returns # of hits per user.

The command includes a GROUP BY AddUser at the end. Also, to test it that it was working, I added a condition not to take the users who were not logged. So, basically, in that situation, the hit would be Hit.AddUser=0. So, this gave me a result of -1, which perfectly makes sense because I do not want to count that user.