[Discussion of "B-tree with space-filling curve to index the tree"] Ahm, you've totally lost me here! I know what B-trees are (did one for a database system I wrote), and I've heard of space-filling curves, but I can't imagine how a curve can be used to index things. Can you say some more about this? -- Chris Gray cg at ami-cg.GraySage.Edmonton.AB.CA