Tom Lane wrote:
> Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> > I can't imagine that the server is avoiding hash aggregation on a 1MB
> > work_mem limit for data that's a few dozen of bytes. Is it really doing
> > that?
>
> Yup:
Aha. Thanks for testing.
> Now that you mention it, this does seem a bit odd, although I remember
> that there's a pretty substantial fudge factor in there when we have
> no statistics (which we don't in this example). If I ANALYZE ctv_data
> then it sticks to the hashagg plan all the way down to 64kB work_mem.
Hmm, so we could solve the complaint by adding an ANALYZE. I'm open to
that; other opinions?
--
Álvaro Herrera http://www.2ndQuadrant.com/
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