Re: retroactive pg10 relnotes: sequence changes

> On Aug 28, 2018, at 1:02 PM, Magnus Hagander <magnus@hagander.net> wrote:
> 
> 
> 
> On Tue, Aug 28, 2018 at 6:34 PM, Alvaro Herrera <alvherre@2ndquadrant.com <mailto:alvherre@2ndquadrant.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.

Jonathan