Subject: Note that ALTER TABLE cannot alter generated stored columns

From: Emre Hasegeli <[email-masked]>
Date: Sun, 30 May 2021 16:25:23 +0300

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.

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From: Laurenz Albe <[email-masked]>
Date: Mon, 31 May 2021 07:42:46 +0200

> useful to note this in the documentation with something like the

+1

Yours,
Laurenz Albe

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From: Peter Eisentraut <[email-masked]>
Date: Wed, 2 Jun 2021 17:00:54 +0200

> useful to note this in the documentation with something like the

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.

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From: Emre Hasegeli <[email-masked]>
Date: Thu, 3 Jun 2021 15:57:24 +0300

> EXPRESSION.  That action doesn't seem related to what you were hoping to do.

I thought that's where it would be if we had ADD/SET EXPRESSION
statements, just like the ADD/SET GENERATED statements just below.