Hi,
The following table is from a database:

Col1    Col2

Al    Ibrahim
Al    Bob
Al     Chuck
Al     Frank
Bob    Gary
Bob    Doug
Chuck    Doug
Chuck    Ed
Chuck    Frank
Doug    Hamza
Gary    Ibrahim
Gary    Hamza

This is the above representation of all connections/links/friendship o
+f each friend:

                        Al--------Frank
                        /|\         |
                      /  |  \       |
                   /     |    \     |    
                /        |      \   |       
             /           |        \ |
          Ibrahim       Bob      Chuck
             \          /|       /  |    
               \       / |     /    |
                 \   /   |   /      |
                 Gary    Doug      Ed
                   \     /
                    \   /
                     \ /
                    Hamza

[download]

I use SELECT (through recursion) to figure out a friend's friends and their friends, it works fine. I am wondering if there is a way (without using recursion-as it causes too much overhead) to be able to figure out who are, say, "AL" 's friends and inturn their friends. In other words, I need to determine how to find a friend's all the friends and their friends(friend of a friend of a friend and so on) without using recursion. I also did some search on sql and "adjacency list" but didn't find much helpful.

Any help is highly appreciated.
Thanks

In reply to sql adjacency list by boulevard

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