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Cute Tricks and Premature Optimizations (Score:2)

by ziggy (25)

The cute trick is to build another table containing the path of each node (".1.5.12.19." means that this is node 19 whose parent is node 12 whose parent is node 5 whose parent is node 1).

Beware that this is a premature optimization.
While this technique works fine with a static tree, it makes tree transformations hideously difficult. Imagine the pain that comes from moving node 12 to be a sibling of node 5, or removing node 5 and consequently promoting their children up a level.
The other technique
- Re:Cute Tricks and Premature Optimizations (Score:1)
  
  by Dom2 (2981) <{dom} {at} {happygiraffe.net}> on 2003.03.31 10:57 (#18542) Homepage Journal
  
  Heh, if you wanted to be really ugly, you could keep the parent id in the sme table, but have a trigger to rebuild the secondary table with the complete path-like listings. It'd be heavy on the database, but might be affordable depending upon how many updates you're doing.
  -Dom
  
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