Re: retroactive pg10 relnotes: sequence changes

> On Aug 28, 2018, at 1:09 PM, Jonathan S. Katz <jkatz(at)postgresql(dot)org> wrote:
>
>
>> On Aug 28, 2018, at 1:02 PM, Magnus Hagander <magnus(at)hagander(dot)net <mailto:magnus(at)hagander(dot)net>> wrote:
>>
>>
>>
>> On Tue, Aug 28, 2018 at 6:34 PM, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com <mailto:alvherre(at)2ndquadrant(dot)com>> wrote:
>> Hello
>>
>> A customer of ours was taken by surprise by a change in Postgres 10 on a
>> trial upgrade from 9.6. They were using sequences from SERIAL columns a
>> little unorthodoxly, and their stuff stopped working: essentially, they
>> hacked the default expression so that it'd automatically use negative
>> numbers when the sequence reached INT_MAX. Since pg10 changed sequences
>> to stop emitting values at that point, it raised an error rather than
>> emit the negative numbers.
>>
>> (In 9.6 and prior, the sequence would emit values past INT_MAX; it was
>> the column that raised the error. In pg10 things were changed so that
>> it is now the sequence that raises the error.)
>>
>> My proposal now is to document this issue in the Postgres 10 release
>> notes. "It's a little late for that!" I hear you say, but keep this in
>> mind: many users have *not* yet upgraded to 10, and they'll keep doing
>> it for years to come still. So I disagree that now is too late. We
>> failed to warn people that already upgraded, but we're still on time to
>> alert people yet to upgrade.
>>
>> I attach both the patch and a screenshot to show how minor the visual
>> effect of the change is.
>>
>> (If people hate this, another option is to make it a separate bullet
>> point.)
>>
>> Looks reasonable to me. And I definitely think we should do it -- people will be upgrading to 10 for years to come, so claiming it's too late is definitely not correct.
>
> +1.
>
> I have attached patch where I suggested some alternate wording and
> remove the parenthetical comment, as I don’t believe that should be
> an aside.

Per off-list discussion from Bruce, re-attaching the patch. Apparently
it was only available in HTML mimepart. Hopefully this gets it into
the archives.

Jonathan