Subject: Re: Note that ALTER TABLE cannot alter generated stored columns
To: emre@hasegeli.com, pgsql-docs@postgresql.org
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From: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Message-ID: <de04e560-2ad7-4edb-28cb-99a2f9eab9b4@enterprisedb.com>
Date: Wed, 2 Jun 2021 17:00:54 +0200
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On 30.05.21 15:25, Emre Hasegeli wrote:
> I was trying to change the generation expression of a generated stored
> column using ALTER TABLE.  It took me a while before I figured SET
> GENERATED applies only to generated identity columns.  I think it'd be
> useful to note this in the documentation with something like the
> attached.

I don't follow why you put this documentation under ALTER TABLE ... DROP 
EXPRESSION.  That action doesn't seem related to what you were hoping to do.