Re: Vacuum DB in Postgres Vs similar concept in other RDBMS

On Wednesday 23 May 2007 20:33, Ron Johnson wrote:
> On 05/23/07 19:17, Chris Browne wrote:
> > harpreet(dot)dhaliwal01(at)gmail(dot)com ("Harpreet Dhaliwal") writes:
> >> I was just wondering if Vacuum Db in postgresql is somehow superior
> >> to the ones that we have in other RDBMS.
> >
> > The thing that is more akin to VACUUM, in Oracle's case, is the
> > rollback segment. In Oracle, Rollback segments are areas in your
> > database which are used to temporarily save the previous values when
> > some updates are going on.
> >
> > In the case of Oracle, if a transaction rolls back, it has to go and
> > do some work to clean up after the dead transaction.
> >
> > This is not *exactly* like PostgreSQL's notion of vacuuming, but
> > that's the nearest equivalent that Oracle has.
>
> That's the only other way to do it, no?
>

You can also take care of the maintenence part both inline (as opposed to a
seperate segment) and at commit time (rather than delay for a vacuum). See
the current HOT patch for a similar implementation to this idea.

--
Robert Treat
Build A Brighter LAMP :: Linux Apache {middleware} PostgreSQL