'
27.12.2011 20:13 пользователь "Tom Lane" <tgl@xxxxxxxxxxxxx> написал:
>
> Jim Crate <jimcfl@xxxxxxxxx> writes:
> > My question is why does it do a seq scan when it flattens this
> > subquery into a JOIN?
>
> Because it thinks there will be 3783 rows out of the msg scan, which if
> true would make your desired nestloop join a serious loser.
But second plan is evaluated cheapier by analyze. I thought this should make it being used unless it is not evaluated. Can it be collapse limit problem or like?