How do you sort a tree stored using the nested set model?

Question

When I refer to nested set model I mean what is described here.

I need to build a new system for storing \"categories\" (I can\'t think of better word for it) in a user

Answer 1

Sorting Nested Sets has no limits and it's not difficult. Just sort by the LEFT bower (anchor, whatever) and it's done. If you have a LEVEL for each node, you can also pull-off correct indentation based on the Level.