"Merlin Moncure" <[EMAIL PROTECTED]> writes: >> You're mistaken, at least with regard to btree indexes.
> hmm. I tried several different ways to filter/extract null values from > an indexed key and got a seq scan every time. I said they were stored, not that you could query against them ;-) IS NULL isn't considered an indexable operator, mainly because it's not an operator at all in the strict sense of the word; and our index access APIs only support querying on indexable operators. The reason they're stored is that they have to be in order to make multi-column indexes work right. I suppose we could special-case single-column indexes, but we don't. In any case, it's more likely that someone would one day get around to making IS NULL an indexable operator than that we'd insert a special case like that. regards, tom lane ---------------------------(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