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From: Tom Lane <tgl@sss.pgh.pa.us>
To: thomas@palan.at
cc: pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #15710: ADD COLUMN IF NOT EXISTS adds constraint anyways
In-reply-to: <15710-f52bad04543be4cb@postgresql.org>
References: <15710-f52bad04543be4cb@postgresql.org>
Comments: In-reply-to PG Bug reporting form <noreply@postgresql.org>
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PG Bug reporting form <noreply@postgresql.org> writes:
> If I want to add a column to a table which and the column may or may not
> already exist, the specified column constraint like UNIQUE is added ever=
y
> time the command is issued, regardless if the column gets added or not.

Yeah, this is the same thing previously reported at

https://www.postgresql.org/message-id/flat/152509815280.19803.161181944522=
13577808%40wrigleys.postgresql.org

We haven't got further than sketching a design for a fix :-(

			regards, tom lane