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Re: Which SQL command creates ExclusiveLock? - Mailing list pgsql-sql

From Tom Lane
Subject Re: Which SQL command creates ExclusiveLock?
Date
Msg-id 22918.1083125788@sss.pgh.pa.us
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In response to Which SQL command creates ExclusiveLock?  ("Denis Khabas" <dkhabas@bluecatnetworks.com>)
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"Denis Khabas" <dkhabas@bluecatnetworks.com> writes:
> According to postgres documentation, all update operations place ROW EXCLUS=
> IVE MODE locks, and=20
> EXCLUSIVE MODE is not automatically acquired by any postgres SQL command. S=
> o, which command places
> ExclusiveLock?

It says that no SQL command acquires ExclusiveLock *on a table*.  The
pg_locks row you show represents ExclusiveLock on a transaction number.
Every transaction gets ExclusiveLock on its transaction number for the
duration of its existence.
        regards, tom lane

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