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yo,

on this page What are the options for storing hierarchical data in a relational database? there is an awesome comparison of options for storing hierarchies. For me it looks like nested set is the best, but there it mentions "Requires a specific sort order". Can anybody explain what exactly does that imply? Will I be able to get a sorted list of ascendants/descendants fast only I sort them by id? Even if I have indexes on other columns that I'm trying to use for sort?

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pokahotass
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1 Answers1

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In the nested set model, the tree structure is implied by the order in which the nodes are traversed.

If you want a sort order different from that for which the tree was created, you have to read the results first, and then sort them manually in a second step. (After rows have been read from a table, indexes are no longer useful.)

CL.
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