MIME-Version: 1.0
From: Fabrice Chapuis <fabrice636861@gmail.com>
Date: Mon, 9 Sep 2024 16:55:01 +0200
Message-ID: <CAA5-nLDmkuRbjHJvf2-Sz0FxtJtoFdrg4mUTy6N84UpZtGZJwQ@mail.gmail.com>
Subject: infinite loop in an update statement
To: pgsql-general@postgresql.org
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Archived-At: <https://www.postgresql.org/message-id/CAA5-nLDmkuRbjHJvf2-Sz0FxtJtoFdrg4mUTy6N84UpZtGZJwQ%40mail.gmail.com>
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Hi,

table a and b are empty, this query does not return. It seems we enter in
infinite loop.
why this update does not return instantly?

UPDATE table_a a
 SET col1 = (SELECT MIN(b.col1)
                    FROM table_b b
                    WHERE b.col2 = a.col2)

Regards,

Fabrice

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