On Sat, Aug 03, 2019 at 05:56:04PM +0200, David Fetter wrote:
> On Tue, Jul 30, 2019 at 02:43:05PM -0700, 毛瑞嘉 wrote:
> > Hi,
> >
> >
> > I wrote a patch for adding CORRESPONDING/CORRESPONDING BY to set operation.
> > It is a task in the todo list. This is how the patch works:
> >
> >
> > I modified transformSetOperationStmt() to get an intersection target list
> > which is the intersection of the target lists of the left clause and right
> > clause for a set operation statement (sostmt). The intersection target list
> > is calculated in transformSetOperationTree() and then I modified the target
> > lists of the larg and rarg of sostmt to make them equal to the intersection
> > target list. Also, I also changed the target list in pstate->p_rtable in
> > order to make it consistent with the intersection target list.
> >
> >
> > I attached the scratch version of this patch to the email. I am not sure
> > whether the method used in the patch is acceptable or not, but any
> > suggestions are appreciated. I will add tests and other related things to
> > the patch if the method used in this patch is acceptable.
>
> I tried adding documentation based on what I could infer about the
> behavior of this patch. Is that documentation correct?
This time, with the patch attached.
Best,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778
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