Re: Writeable CTEs patch

Robert Haas escribió:
> On Mon, Feb 8, 2010 at 1:01 PM, Marko Tiikkaja
> <marko(dot)tiikkaja(at)cs(dot)helsinki(dot)fi> wrote:
> >> Could we just write, e.g.
> >> "non-SELECT statements are not allowed within a cursor declaration?"
> >> Or we could say "INSERT, UPDATE, and DELETE statements are not allowed
> >> within a cursor declaration", but I'm thinking we may want to allow
> >> things like COPY and EXPLAIN inside CTEs in the future, too, and
> >> they'll presumably be treated similarly to DML.
> >
> > "INSERT, UPDATE and DELETE" is quite long and "non-SELECT" is a bit
> > clumsy IMO.  But I don't really have anything better to offer, either.
>
> Yeah, I don't feel good about "INSERT, UPDATE, and DELETE" because in
> most of the relevant contexts the list might get longer if in the
> future we allow things like EXPLAIN and COPY within CTEs. I think
> "Non-SELECT statement" is reasonably clear, though; people might not
> know which things are statements, but the message implies that SELECT
> is one such thing, and not the one that's the problem, which should
> get them pointed in the right direction.

Hmm, how about VALUES? Isn't that a statement on its own right, that
would similarly unaffected?

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