is that done on T-SQL?  I think it has to be done with the Management Studio.

http://www.youtube.com/watch?v=QDIHfE5utkk

The youtube video instructs to use this syntax.  But what is the constraint?  Which table should be altered -- the main one or the index table?

This instructional video does not explain how it is to be done.  It shows how to create the required three constraints but nothing beyond that.  So, what else do I do?