Re: BUG #6360: with hold cursor, cause function executed twice and wrong results

On Tue, Dec 27, 2011 at 12:47 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> wcting163(at)163(dot)com writes:
>> The reason is that the function p_test_execute is executed twice, when
>> *fetch*, it is first executed, and when transaction commit, because the
>> cursor is a *holdable* cursor, it is executed again.
>
> Yup.  I don't particularly see this as a bug.  If you were to manually
> rewind and rescan the cursor (ie, MOVE BACKWARD ALL and re-fetch),
> the function would be executed multiple times too.  If you don't want
> that to happen, the best way would be to commit the transaction
> immediately, not fetch some rows and then commit.

Is that even per spec? I would not expect the results, or the
side-effects, of a query to depend on the method used to retrieve its
results.

--
Robert Haas
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