On Sat, Dec 6, 2014 at 10:08 PM, Tomas Vondra <tv(at)fuzzy(dot)cz> wrote:
> select a.i, b.i from a join b on (a.i = b.i);
I think the concern is that the inner side might be something more
elaborate than a plain table scan, like an aggregate or join. I might
be all wet, but my impression is that you can make rescanning
arbitrarily expensive if you work at it.
--
Robert Haas
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