The problem with this is that you can't do a single select query to get an entire branch of the tree in the correct order. You have to write something like a recursive function and you end up with one query per level of the tree.

Someone above mentioned "nested set" - this is what I use and it's great for quick lookups, at the cost of expensive (relatively) inserts. I've never had a database big enough where inserts have been a problem.

In reply to Re^2: Trees in SQL, adjacency lists and sorting. by saberworks
in thread Trees in SQL, adjacency lists and sorting. by BUU

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