From: Bruce Momjian <pgman@candle.pha.pa.us>
Message-Id: <200304251447.h3PEluQ11745@candle.pha.pa.us>
Subject: Re: point-in-time recovery
In-Reply-To: <200304252015.15089.mallah@trade-india.com>
To: Rajesh Kumar Mallah <mallah@trade-india.com>
Date: Fri, 25 Apr 2003 10:47:56 -0400 (EDT)
Cc: pgsql-admin@postgresql.org
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Rajesh Kumar Mallah wrote:
> 
> 
> Thanks for responding , but i still have
> more to discuss.
> 
> On Friday 25 Apr 2003 7:47 pm, Bruce Momjian wrote:
> > Rajesh Kumar Mallah wrote:
> > > What is this PITR anyway ?
> > >
> > > when it comes will i be able to
> > >
> > > 1. reduce by pg_dump times ?
> > > 2. can afford to run pg_dump less frequently ?
> > > 3. Will be able to rollback committed transactions of past 5 mins?
> >
> > You can do a dump,
> 
> Do u mean pg_dump here, or some special command
> thats doing a quick snapshot dump?

You do one pg_dump, the start PITR logging.

> 
>  then do continuous logging of all database changes
> is this logging happening automatically for i have to give some
> special command to start logging?

Not sure yet --- we arn't done, but it will probably be a special
command.

> 
> > until the next backup.  If you crash in the middle of the day, you can
> > recover up to the point of the crash.
> 
> say i do not crash but do a 
> 
> psql> DELETE from  TABLE_NAME ;
> DELETE 1021
> psql> Ooops what did i do , damn my last backup is 6 hrs old  ??
> 
> does PITR help me here?

Ideally, you will be able to restore to any point you wish, such as
before the DELETE.  However, I do not know if that control will be
implemented in 7.4, but if not, certainly 7.5.

-- 
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