Bradley Baetz <[EMAIL PROTECTED]> writes: > Hmm. OK, I poked through the code a bit more, and I think I now realise > why we were talking across each other. I've attached a 'patch' which > gets the mergejoin counts down to something reasonable.
I've just committed a significant set of changes in the join cost estimation routines. On looking closer, they hadn't been upgraded for any of the recent changes --- they were still assuming that merge and hash join clauses could only be simple var = var, for instance. I did something about the mergejoin rescan issue, as well as modeling JOIN short-circuiting. All of the estimates are a bit crude, but certainly better than no model at all. I think this covers your concerns, though I'm still worried about whether it's okay to use the existing selectivity routines to compute selectivities in the JOIN_IN/JOIN_UNIQUE case. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 2: you can get off all lists at once with the unregister command (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED])