On Thu, Jun 2, 2011 at 2:56 PM, Claudio Freire <klaussfreire@gmail.com> wrote:
> On Thu, Jun 2, 2011 at 4:57 PM, Kevin Grittner
> <Kevin.Grittner@wicourts.gov> wrote:
>> And the
>> planner does take the size of work_mem and the expected data set
>> into consideration when estimating the cost of the hash join.
>
> And shouldn't it?
>
> In a gross mode, when hash joins go to disk, they perform very poorly.
> Maybe the planner should take that into account.
It does.
--
Robert Haas
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