"Chris Velevitch" <chris.velevitch@xxxxxxxxx> writes: > I have a query on a table:- > X between k1 and k2 or X < k1 and Y <> k3 > where k1, k2, k3 are constants. > How would this query work, if I created an index on X and a partial > index on X where Y <> k3? Is it worth the trouble? You didn't mention the statistics involved, but ordinarily I'd think a non-equal condition is too nonselective to justify the cost of maintaining an extra index. The real problem here is that "X < k1" is probably too nonselective as well, which will likely lead the planner to decide that a plain seqscan is the cheapest solution. In principle the above could be done with a BitmapOr of two indexscans on X, but unless the constants are such that only a small fraction of rows are going to be selected, it's likely that a seqscan is the way to go. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
