Re: Writeable CTEs and empty relations

On 2010-02-10 23:57 +0200, Tom Lane wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> If the executor has buried in it the assumption that the snapshot
>> can't change after startup, then does that mean that we need to start
>> up and shut down the executor for each subquery?
>
> Yes, I think so. That's the way it's always worked in the past;
> see for example PortalRunMulti() and ProcessQuery(). I think trying
> to change that is a high-risk, low-reward activity.
>
> This probably means that the planner output for queries involving
> writeable CTEs has to be a separate PlannedStmt per such CTE.

I'm looking at this, but I can't think of any good way of associating
the tuplestores from PortalRunMulti() with the correct CTEs. Any ideas?

Regards,
Marko Tiikkaja