I have been exploring a different alternative for tree structures; it
would also be efficient for some other hierarchical structures. I
started to write it down, then got diverted to other issues ...
In any case, as long as your structures satisfy:
- no node can have more than (say) 4 million children
- the structure may not be deeper than (say) 100 levels
this representation may suit your needs better than the one from
'SQL for Smarties': it is as fast as that one on lookup, much faster
on insert and delete.
If you want to take a look at a (very) preliminary description I
started writing back in may, download the
preliminary paper and coding function .
Do not hesitate to contact me if you are interested in the stuff and
think I may help implementing it.
