[wp-hackers] Category Operation (Adjacency vs. Modified Preorder)

[Chris Johnson]

> sql tree preordering works nice, but imho implementing them without
> transactions and triggers is really asking for trouble.

Yeah, that's the downside of basicly going from one tree index (cat_parent) 
to three( left, right, parent). There are three index's that can get fouled 
up with a bad write operation.

I suppose performing an index check after every insert/update might be a bit 
excessive .. or would it?