Re: Fix showing XID of a spectoken lock in an incorrect field of pg_locks view. - Mailing list pgsql-hackers

From Amit Kapila
Subject Re: Fix showing XID of a spectoken lock in an incorrect field of pg_locks view.
Date
Msg-id CAA4eK1LaHo_85uHRtAscYNTbw6ZjZFy0tFdD7tCzXVEtxDnUwQ@mail.gmail.com
Whole thread Raw
In response to Fix showing XID of a spectoken lock in an incorrect field of pg_locks view.  (Masahiko Sawada <sawada.mshk@gmail.com>)
Responses Re: Fix showing XID of a spectoken lock in an incorrect field of pg_locks view.
List pgsql-hackers
On Wed, Jan 4, 2023 at 12:16 PM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>
> It seems to be confusing and the user won't get the result even if
> they search it by transactionid = 741. So I've attached the patch to
> fix it. With the patch, the pg_locks views shows like:
>
>  locktype  | database | relation | page | tuple | virtualxid |
> transactionid | classid | objid | objsubid | virtualtransaction |  pid
>   |     mode      | granted | fastpath | waitstart
>
-----------+----------+----------+------+-------+------------+---------------+---------+-------+----------+--------------------+--------+---------------+---------+----------+-----------
>  spectoken |          |          |      |       |            |
>   746 |         |     1 |          | 3/4                | 535618 |
> ExclusiveLock | t       | f        |
> (1 row)
>

Is it a good idea to display spec token as objid, if so, how will
users know? Currently for Advisory locks, we display values in
classid, objid, objsubid different than the original meaning of fields
but those are explained in docs [1]. Wouldn't it be better to mention
this in docs?

[1] - https://www.postgresql.org/docs/devel/view-pg-locks.html

-- 
With Regards,
Amit Kapila.



pgsql-hackers by date:

Previous
From: vignesh C
Date:
Subject: Re: POC: Lock updated tuples in tuple_update() and tuple_delete()
Next
From: vignesh C
Date:
Subject: Re: Parallelize correlated subqueries that execute within each worker