27.12.2011 20:13 пользователь "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> написал:
> Jim Crate <jimcfl(at)gmail(dot)com> 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?
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