Re: (docs): add missing info about ShareLocks - Mailing list pgsql-docs

From Laurenz Albe
Subject Re: (docs): add missing info about ShareLocks
Date
Msg-id 58e8295701c9e15c251ed608c5ed297688c785a2.camel@cybertec.at
Whole thread Raw
In response to (docs): add missing info about ShareLocks  (Alpha Shuro <alphashuro@gmail.com>)
Responses Re: (docs): add missing info about ShareLocks
List pgsql-docs
On Sat, 2025-11-22 at 09:07 +0100, Alpha Shuro wrote:
> I had a production incident a few weeks ago while using deferred indexes, where
> the Postgres docs lead me down the wrong path of investigation due to missing details.
> Specifically, the docs implied that a `ShareLock` was only acquired when creating
> indexes, but only after looking at the code did I learn that this lock is also
> acquired when transactions are waiting for other transactions to complete.
> I think this would be helpful to someone who might find themselves on the same path
> in the future, and as I understand it this mailing list is the way to submit patches
> to the docs?

No, that is wrong.  This section is about table locks, and a lock on a transaction ID
should, if anywhere, be documented elsewhere.  Actually, there is already something
about transaction ID locks in https://www.postgresql.org/docs/current/xact-locking.html

Perhaps you could improve that short documentation?

Yours,
Laurenz Albe

PS: There are also SHARE locks on rows.



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