Re: Problem with identity column & related sequences

Thanks. I was sort of expecting that answer but I didn't see where it
was addressed specifically.  Unfortunately I'm stuck on v12 for the
time being so I guess it's back to the workaround.

On Tue, Sep 28, 2021 at 2:13 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> Jeff Hoffmann <jeff@propertykey.com> writes:
> > I am using postgresql-12.8.  I am using I am making use of an identity
> > column for part of a scripts to process some updated data.  Because of
> > the way the script is called I don't necessarily know if this column
> > is going to exist in the table I am working on so I have a step that
> > will conditionally create the column if it doesn't already exist, i.e.
>
> > alter table mytable add column if not exists unique_id integer
> > generated always as identity;
>
> You're right, this sort of thing does not work very well in v12 and
> before.  We fixed it in v13, but the changes seemed far too invasive
> to risk a back-patch [1].
>
>                         regards, tom lane
>
> [1] https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=1281a5c90



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Jeff Hoffmann
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PropertyKey
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