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Re: >= and <= operator
At 10:45 AM 3/20/00 +0800, Lai Yiu Fai wrote:
>It seems that the filter operators <= and >= don't make any use of any built
>indexes such as eq, pres, sub. It scans through all the entries for query
>results. Is there any ways to improve performance for these filter operators?
Yes. The pres index could be used to eliminate entries which
do not have the attribute time in question. But the others are
not generally helpful for eliminating candidates. One could
maintain an index especially designed for orderring matching.
Something simple, like an orderred tree, could be used. More
elegant approaches are, of course, possible.
This wouldn't be too hard to code. Feel free to give it a whirl.