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* select locks table for updates
@ 2020-11-19 10:06 Yambu <hyambu@gmail.com>
2020-11-19 10:19 ` RE: select locks table for updates Michel SALAIS <msalais@msym.fr>
0 siblings, 1 reply; 5+ messages in thread
From: Yambu @ 2020-11-19 10:06 UTC (permalink / raw)
To: Pgsql-admin <pgsql-admin@lists.postgresql.org>
Hi
Does a select lock tables for updates?
^ permalink raw reply [nested|flat] 5+ messages in thread
* RE: select locks table for updates
2020-11-19 10:06 select locks table for updates Yambu <hyambu@gmail.com>
@ 2020-11-19 10:19 ` Michel SALAIS <msalais@msym.fr>
2020-11-19 10:27 ` Re: select locks table for updates Alexander Shelemin <shelemin@gmail.com>
2020-11-19 21:13 ` Re: select locks table for updates Simon Riggs <simon@2ndquadrant.com>
0 siblings, 2 replies; 5+ messages in thread
From: Michel SALAIS @ 2020-11-19 10:19 UTC (permalink / raw)
To: 'Yambu' <hyambu@gmail.com>; 'Pgsql-admin' <pgsql-admin@lists.postgresql.org>
No! Not in PostgreSQL.
However it is true for SQL Server.
Michel SALAIS
De : Yambu <hyambu@gmail.com>
Envoyé : jeudi 19 novembre 2020 11:07
À : Pgsql-admin <pgsql-admin@lists.postgresql.org>
Objet : select locks table for updates
Hi
Does a select lock tables for updates?
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: select locks table for updates
2020-11-19 10:06 select locks table for updates Yambu <hyambu@gmail.com>
2020-11-19 10:19 ` RE: select locks table for updates Michel SALAIS <msalais@msym.fr>
@ 2020-11-19 10:27 ` Alexander Shelemin <shelemin@gmail.com>
1 sibling, 0 replies; 5+ messages in thread
From: Alexander Shelemin @ 2020-11-19 10:27 UTC (permalink / raw)
To: Michel SALAIS <msalais@msym.fr>; +Cc: Yambu <hyambu@gmail.com>; Pgsql-admin <pgsql-admin@lists.postgresql.org>
That depends on transaction isolation level. By default sql server doesn't
use MVCC, so selects need shared locks. It's easily changed, though.
On Thu, 19 Nov 2020, 11:20 Michel SALAIS, <msalais@msym.fr> wrote:
> No! Not in PostgreSQL.
>
> However it is true for SQL Server.
>
>
>
> *Michel SALAIS*
>
> *De :* Yambu <hyambu@gmail.com>
> *Envoyé :* jeudi 19 novembre 2020 11:07
> *À :* Pgsql-admin <pgsql-admin@lists.postgresql.org>
> *Objet :* select locks table for updates
>
>
>
> Hi
>
>
>
> Does a select lock tables for updates?
>
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: select locks table for updates
2020-11-19 10:06 select locks table for updates Yambu <hyambu@gmail.com>
2020-11-19 10:19 ` RE: select locks table for updates Michel SALAIS <msalais@msym.fr>
@ 2020-11-19 21:13 ` Simon Riggs <simon@2ndquadrant.com>
2020-11-19 22:31 ` RE: select locks table for updates Michel SALAIS <msalais@msym.fr>
1 sibling, 1 reply; 5+ messages in thread
From: Simon Riggs @ 2020-11-19 21:13 UTC (permalink / raw)
To: Michel SALAIS <msalais@msym.fr>; +Cc: Yambu <hyambu@gmail.com>; Pgsql-admin <pgsql-admin@lists.postgresql.org>
On Thu, 19 Nov 2020 at 10:20, Michel SALAIS <msalais@msym.fr> wrote:
>
> No! Not in PostgreSQL.
In normal SELECTs, that is correct.
If you use SELECT ... FOR UPDATE then rows will be locked.
--
Simon Riggs http://www.EnterpriseDB.com/
^ permalink raw reply [nested|flat] 5+ messages in thread
* RE: select locks table for updates
2020-11-19 10:06 select locks table for updates Yambu <hyambu@gmail.com>
2020-11-19 10:19 ` RE: select locks table for updates Michel SALAIS <msalais@msym.fr>
2020-11-19 21:13 ` Re: select locks table for updates Simon Riggs <simon@2ndquadrant.com>
@ 2020-11-19 22:31 ` Michel SALAIS <msalais@msym.fr>
0 siblings, 0 replies; 5+ messages in thread
From: Michel SALAIS @ 2020-11-19 22:31 UTC (permalink / raw)
To: 'Simon Riggs' <simon@2ndquadrant.com>; +Cc: 'Yambu' <hyambu@gmail.com>; 'Pgsql-admin' <pgsql-admin@lists.postgresql.org>
I think the original question wasn't about what can be done. Any way that is how I considered it. A simple question, a simple reply taking into account default behavior only. The point was just to say that things don't go the same everywhere...
Michel SALAIS
-----Message d'origine-----
De : Simon Riggs <simon@2ndquadrant.com>
Envoyé : jeudi 19 novembre 2020 22:14
À : Michel SALAIS <msalais@msym.fr>
Cc : Yambu <hyambu@gmail.com>; Pgsql-admin <pgsql-admin@lists.postgresql.org>
Objet : Re: select locks table for updates
On Thu, 19 Nov 2020 at 10:20, Michel SALAIS <msalais@msym.fr> wrote:
>
> No! Not in PostgreSQL.
In normal SELECTs, that is correct.
If you use SELECT ... FOR UPDATE then rows will be locked.
--
Simon Riggs http://www.EnterpriseDB.com/
^ permalink raw reply [nested|flat] 5+ messages in thread
end of thread, other threads:[~2020-11-19 22:31 UTC | newest]
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2020-11-19 10:06 select locks table for updates Yambu <hyambu@gmail.com>
2020-11-19 10:19 ` Michel SALAIS <msalais@msym.fr>
2020-11-19 10:27 ` Alexander Shelemin <shelemin@gmail.com>
2020-11-19 21:13 ` Simon Riggs <simon@2ndquadrant.com>
2020-11-19 22:31 ` Michel SALAIS <msalais@msym.fr>
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