On Tue, March 6, 2007 03:17, Heikki Linnakangas wrote: > I think you've just described a range-encoded bitmap index. The idea is > to divide the range of valid values into a some smallish number of > subranges, and for each of these boundary values you store a bitmap > where you set the bit representing every tuple with value < boundary > value.
That's pretty cool! From the looks of it, what you describe would solve my problem--but using more storage in return for more flexibility. My scheme really required a correlation between a value and storage order, which can be pretty fragile. These range-encoded bitmap indexes wouldn't have that problem. I guess if you did simple run-length compression on these bitmaps you'd end up more or less where I came in. But you wouldn't want to flip a bit somewhere in the middle of a compressed data stream, of course. :-) Jeroen ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly