Hi guys,

I've been taught about the adjacency list model recently ( http://sqllessons.com/categories.html ) and there is one thing I would like to know about its use : what query to use when you simply want to count the number of sub-items contained in one specific category? (by using its index ID)

For example, using the table example found in the url above, what if we needed to know the total number of sub-items (categories+items) that are under "doggie"?

Thanks for your insights !