Re: [HACKERS] Couple of issues with prepared FETCH commands

On Tue, Jan 10, 2017 at 5:38 PM, Andrew Gierth
<andrew@tao11.riddles.org.uk> wrote:
> But the problem that actually came up is this: if you do the PQprepare
> before the named cursor has actually been opened, then everything works
> _up until_ the first event, such as a change to search_path, that forces
> a revalidation; and at that point it fails with the "must not change
> result type" error _even if_ the cursor always has exactly the same
> result type.  This happens because the initial prepare actually stored
> NULL for plansource->resultDesc, since the cursor name wasn't found,
> while on the revalidate, when the cursor obviously does exist, it gets
> the actual result type.
>
> It seems a bit of a "gotcha" to have it fail in this case when the
> result type isn't actually being checked in other cases.

To me, that sounds like a bug.

-- 
Robert Haas
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