Re: lock entire database - Mailing list pgsql-novice

From Ron St-Pierre
Subject Re: lock entire database
Date
Msg-id 4113CBAB.2020904@syscor.com
Whole thread Raw
In response to lock entire database  (Benjamin <benjamin@netyantra.com>)
Responses Re: lock entire database
List pgsql-novice
Benjamin wrote:

>
> Thanx Ron for that.
> I got the listing of the tables.
> The \d option gives u a formatter output. I just wanted a list , that
> i cud loop on.
> I guess that cud be done with a simple "SELECT tablename from
> pg_tables where schemaname='public' ".
>
> Now to the need to lock the database. I need to backup the database at
> run-time, on another machine, which is a backup for the first one. So
> the data has to match exactly as on the first. So till the backup
> faithfuly copies everything down, there shud be no changes on the main
> machine.
>
Postgres uses MVCC (multiversion concurrency control) which basically
means that each transaction takes a snapshot of the database when a user
performs a query (read, update, whatever). So if a pg_dump of the entire
database occurs within a single transaction, this would ensure that you
have a valid snapshot at one particular instance. *Can anyone verify if
this is indeed true*?

If that is true then a pg_dump should solve your problem.

Ron

ps pls post your responses to the list too.


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