Re: Tree structure table normalization problem (do I need atrigger?)
От
Frank Joerdens
Тема
Re: Tree structure table normalization problem (do I need
atrigger?)
Дата
Msg-id
3A3F6006.ECDE92AE@joerdens.de
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Дерево обсуждения
Re: Tree structure table normalization problem (do I need a
trigger?) Ron Peterson <ron.peterson@yellowbank.com>
Tulassay Zsolt wrote: [ . . . ] > The SQL stuff of that nested set structure is fairly easy, I wrote some > quick'n'dirty plpgsql functions that will do inserts, updates, deletes > from the tree, display level number etc. What scared me about it in particular was one scenario where you try to delete a subtree. This would normally leave a gap, since the structure is based on the worm's ability to get from one node to the next with an increment of just 1. Once you had a subtree deleted, you'd either would have to have the worm leap-frog (a leaping frog-worm?!! :)) the gap or update an entire half of the tree to close it . . . then my brain started to hurt and I gave up. > I can send it to you if you like (please allow a few days since I > have several exams at the university this week). Sure, I'd like to have a look at it! Thanks, Frank
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От: Frank Joerdens
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