On 22 September 2015 at 21:14, Alvaro Herrera <alvhe...@2ndquadrant.com>
> Robert Haas wrote:
> > On Tue, Sep 22, 2015 at 10:34 AM, Simon Riggs <si...@2ndquadrant.com>
> > > For 1, Gather makes most sense.
> > Yeah, I'm leaning that way myself. Amit argued for "Parallel Gather"
> > but I think that's overkill. There can't be a non-parallel gather,
> > and long names are a pain.
> "Gather" seems a pretty decent choice to me too, even if we only have a
> single worker (your "1"). I don't think there's much need to
> distinguish 1 from 2, is there?
I think so. 1 is Many->1 and the other is 1->Many.
You may wish to do an operation like a parallel merge join.
Parallel Sort -> Scatter -> Parallel Merge
Simon Riggs http://www.2ndQuadrant.com/
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