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Date: Tue, 7 Mar 2023 12:59:58 +0100
From: hubert depesz lubaczewski <depesz@depesz.com>
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To: Joseph Hammerman <joe.hammerman@datadoghq.com>
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Subject: Re: Migrating tables to new schema with minimal downtime
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On Mon, Mar 06, 2023 at 01:00:15PM -0800, Joseph Hammerman wrote:
> Would it be data safe if I took an ACCESS EXCLUSIVE lock on the table?

alter table gets ACCESS EXCLUSIVE lock on its own.

You can test it trivially in psql on some side table.

Best regards,

depesz