Re: Snapshot too old logging

On Tue, Nov 15, 2016 at 2:25 PM, Magnus Hagander <magnus@hagander.net> wrote:
> On Tue, Nov 15, 2016 at 8:22 PM, Robert Haas <robertmhaas@gmail.com> wrote:
>>
>> On Tue, Nov 15, 2016 at 2:21 PM, Kevin Grittner <kgrittn@gmail.com> wrote:
>> > On Tue, Nov 15, 2016 at 12:43 PM, Robert Haas <robertmhaas@gmail.com>
>> > wrote:
>> >
>> >> I think it would be better not to include either the snapshot or the
>> >> block number, and just find some way to reword the error message so
>> >> that it mentions which relation was involved without implying that all
>> >> access to the relation would necessarily fail.  For example:
>> >>
>> >> ERROR: snapshot too old
>> >> DETAIL: One or more rows required by this query have already been
>> >> removed from "%s".
>> >
>> > That particular language would be misleading.  All we know about
>> > the page is that it was modified since the referencing (old)
>> > snapshot was taken.  We don't don't know in what way it was
>> > modified, so we must assume that it *might* have been pruned of
>> > rows that the snapshot should still be able to see.
>>
>> Oh, yeah.  So maybe "may have already been removed".
>
>
> Just to be clear, you're suggesting 'One or more rows may have already been
> removed from "%s"?

I think I was suggesting: One or more rows required by this query may
already have been removed from "%s".

-- 
Robert Haas
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