Re: "Correct" term for a 1:1 relationship between a "database" and an "instance" where > 1 such things are on the same physical server?
From: joel garry <joel-garry_at_home.com>
Date: Fri, 24 Jul 2009 16:11:04 -0700 (PDT)
Message-ID: <2bab9962-ce06-4252-a49e-0ac874e91d7f_at_a37g2000prf.googlegroups.com>
On Jul 24, 12:58 pm, Mark D Powell <Mark.Pow..._at_eds.com> wrote:
> On Jul 22, 10:29 am, ddf <orat..._at_msn.com> wrote:
>
>
>
> > On Jul 22, 8:37 am, dana <dana_at_w..._at_yahoo.com> wrote:
>
> > > Here's another question for you:
>
> > > 1) Would there ever be any practical reason for two instances (procs +
> > > SGA) to access the same database (collection of data treated as a
> > > unit) on the same, unpartitioned physical server?
>
> > > Dana
>
> > > Dana
>
> > That, I believe, is the basic definition of RAC -- two or more
> > instances accessing a single database.
>
> > David Fitzjarrell
>
> But with RAC you would expect each instance to be running concurrently
> on different servers. While some Oracle 'experts' have managed to
> create a RAC setup with multiple instances on a single server the set
> up is non-standard, unsupported, and for demonstartion purposes only.
>
> On a UNIX platform it used to be fairly easy to change the instance
> idenifier, SID, that was used to identify a running Oracle instance
> used to access a database. That is you could shut the instance down,
> make a few quick changes, and start a differently named instance then
> access the same database you were just working with from a different
> instance name. Only one instance can access a non-RAC database at a
> time. There was little practical application for this functionality.
>
> HTH -- Mark D Powell --
Date: Fri, 24 Jul 2009 16:11:04 -0700 (PDT)
Message-ID: <2bab9962-ce06-4252-a49e-0ac874e91d7f_at_a37g2000prf.googlegroups.com>
On Jul 24, 12:58 pm, Mark D Powell <Mark.Pow..._at_eds.com> wrote:
> On Jul 22, 10:29 am, ddf <orat..._at_msn.com> wrote:
>
>
>
> > On Jul 22, 8:37 am, dana <dana_at_w..._at_yahoo.com> wrote:
>
> > > Here's another question for you:
>
> > > 1) Would there ever be any practical reason for two instances (procs +
> > > SGA) to access the same database (collection of data treated as a
> > > unit) on the same, unpartitioned physical server?
>
> > > Dana
>
> > > Dana
>
> > That, I believe, is the basic definition of RAC -- two or more
> > instances accessing a single database.
>
> > David Fitzjarrell
>
> But with RAC you would expect each instance to be running concurrently
> on different servers. While some Oracle 'experts' have managed to
> create a RAC setup with multiple instances on a single server the set
> up is non-standard, unsupported, and for demonstartion purposes only.
>
> On a UNIX platform it used to be fairly easy to change the instance
> idenifier, SID, that was used to identify a running Oracle instance
> used to access a database. That is you could shut the instance down,
> make a few quick changes, and start a differently named instance then
> access the same database you were just working with from a different
> instance name. Only one instance can access a non-RAC database at a
> time. There was little practical application for this functionality.
>
> HTH -- Mark D Powell --
Wasn't there something about oltp tuning during the day, then batch/ report at night? Something is poking at the back of my brain, maybe it wasn't oracle.
jg
-- _at_home.com is bogus http://www.reuters.com/article/rbssTechMediaTelecomNews/idUSN2142553620090722Received on Fri Jul 24 2009 - 18:11:04 CDT