> If you mean the indexscan optimization, we do know how to estimate the
> cost of the indexscans, because that depends mostly on the behavior of
> the added < or > condition(s). This does not imply knowing how to
> estimate the behavior of >>= itself.
If we can estimate the cost of the indexscan, why can't we estimate the
rowcount? Sorry if I'm being dense here, but I really don't understand
how the special operator code works at all.
--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com