Message-ID: <3cc08f35825c14458c4cd345ef449211d37ddc49.camel@cybertec.at>
Subject: Re: How to explicitly lock and unlock tables in pgsql?
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Merlin Moncure <mmoncure@gmail.com>
Cc: Shaozhong SHI <shishaozhong@gmail.com>, pgsql-general
	 <pgsql-general@lists.postgresql.org>
Date: Fri, 18 Mar 2022 23:48:41 +0100
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On Fri, 2022-03-18 at 11:38 -0500, Merlin Moncure wrote:
> > Also, you should nevr explicitly lock tables.  Table locks are taken automatically
> > by the SQL statements you are executing.
> 
> Isn't that a bit of overstatement?
> LOCK table foo;
> 
> Locks the table, with the benefit you can choose the lockmode to
> decide what is and is not allowed to run after you lock it.  The main
> advantage vs automatic locking is preemptively blocking things so as
> to avoid deadlocks.

Yes, that was an overstatement.
But I find that 90% of the time when people explicitly lock a table
it is not the correct solution.

Yours,
Laurenz Albe