Re: retroactive pg10 relnotes: sequence changes

[Alvaro Herrera]

On 2018-Aug-28, Jonathan S. Katz wrote:

> 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.

Cool, thanks.  I have pushed it with your proposed wording.

-- 
Álvaro Herrerahttps://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Re: retroactive pg10 relnotes: sequence changes

[Andres Freund]

On 2018-08-28 19:02:06 +0200, Magnus Hagander wrote:
> 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.

Please make sure to backpatch it to all branches carrying v10 release
notes...

Greetings,

Andres Freund

Re: retroactive pg10 relnotes: sequence changes

[Jonathan S. Katz]

On Aug 28, 2018, at 1:09 PM, Jonathan S. Katz  wrote:On Aug 28, 2018, at 1:02 PM, Magnus Hagander  wrote:On Tue, Aug 28, 2018 at 6:34 PM, Alvaro Herrera  wrote:HelloA customer of ours was taken by surprise by a change in Postgres 10 on atrial upgrade from 9.6.  They were using sequences from SERIAL columns alittle unorthodoxly, and their stuff stopped working: essentially, theyhacked the default _expression_ so that it'd automatically use negativenumbers when the sequence reached INT_MAX.  Since pg10 changed sequencesto stop emitting values at that point, it raised an error rather thanemit the negative numbers.(In 9.6 and prior, the sequence would emit values past INT_MAX; it wasthe column that raised the error.  In pg10 things were changed so thatit is now the sequence that raises the error.)My proposal now is to document this issue in the Postgres 10 releasenotes.  "It's a little late for that!" I hear you say, but keep this inmind: many users have *not* yet upgraded to 10, and they'll keep doingit for years to come still.  So I disagree that now is too late.  Wefailed to warn people that already upgraded, but we're still on time toalert people yet to upgrade.I attach both the patch and a screenshot to show how minor the visualeffect of the change is.(If people hate this, another option is to make it a separate bulletpoint.)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 andremove the parenthetical comment, as I don’t believe that should bean aside.Per off-list discussion from Bruce, re-attaching the patch. Apparentlyit was only available in HTML mimepart. Hopefully this gets it intothe archives.Jonathan

sequences-10-v2.patch
Description: Binary data


signature.asc
Description: Message signed with OpenPGP

Re: retroactive pg10 relnotes: sequence changes

[Magnus Hagander]

On Tue, Aug 28, 2018 at 6:34 PM, Alvaro Herrera 
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.

-- 
 Magnus Hagander
 Me: https://www.hagander.net/ 
 Work: https://www.redpill-linpro.com/