Great article Gus!
I haven't had a chance to play around with HiearchyIDs myself yet but I must put it on my agenda to try it out. And your examples are a great place to start an analysis.
I'm also interested to see if there are any variations to the hiearchy traversal methods of adjacency lists that might yield better performance, although I doubt I'm smart enough to figure them out. 🙂
I did have one recent case that I was able to improve though. So it may be possible.
My thought question: Have you ever been told that your query runs too fast?
My advice:
INDEXing a poor-performing query is like putting sugar on cat food. Yeah, it probably tastes better but are you sure you want to eat it?
The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.
Need to UNPIVOT? Why not CROSS APPLY VALUES instead?[/url]
Since random numbers are too important to be left to chance, let's generate some![/url]
Learn to understand recursive CTEs by example.[/url]
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