Re: How to share the result data of separated plan

On Sun, Nov 7, 2010 at 1:08 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Marko Tiikkaja <marko(dot)tiikkaja(at)cs(dot)helsinki(dot)fi> writes:
>> On 2010-11-07 6:23 PM +0200, Tom Lane wrote:
>>> Um ... why?  I thought the whole point of breaking out ModifyTable
>>> as a separate node type was so that a query involving writeable CTEs
>>> would still be just one plan tree.
>
>> We tried that for 9.0 and it didn't work.  Almost all work for 9.1 has
>> been spent on creating an infrastructure for running the executor
>> separately for every WITH list element when wCTEs are present.
>
> I guess I shoulda been paying closer attention :-(.  That really, really
> seems like fundamentally the wrong direction.  What was it that was
> unfixable about the other way?  If it is unfixable, should we revert
> ModifyTable?

The relevant thread is here:

http://archives.postgresql.org/pgsql-hackers/2010-02/msg00783.php

--
Robert Haas
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