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: Shakespeare <whatsin_at_xs4all.nl>
Date: Sat, 25 Jul 2009 13:04:56 +0200
Message-ID: <4a6ae6d6$0$187$e4fe514c_at_news.xs4all.nl>
joel garry schreef:
>> 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: Sat, 25 Jul 2009 13:04:56 +0200
Message-ID: <4a6ae6d6$0$187$e4fe514c_at_news.xs4all.nl>
joel garry schreef:
> 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/idUSN2142553620090722
Taken to the letter, a database on (backup) tape or other media is still a database, but not an instance.
Shakespeare
(What's in a name?) Received on Sat Jul 25 2009 - 06:04:56 CDT