Re: ORACLE installation - instance - database

Strictly the relationship is many to 1. many instances *can* manage one database. This requires OPS. A database is a set of files. an instance is a set of memory structures and processes.

Having said that most people don't run OPS. So in general Sybrands statement is correct.

--
Niall Litchfield
Oracle DBA
Audit Commission UK
"Sybrand Bakker" <postbus_at_sybrandb.demon.nl> wrote in message
news:ta6dr8q4qc1qcd_at_beta-news.demon.nl...


> Relationship between instance and database is 1 to 1.

> One instance will manage only one database

> You can create multiple instances on one server and whether or not you use

> multiple different versions of Oracle doesn't really matter. Of course,

 when


> you are using only one version of Oracle, it should be installed only

 once.


> The questions you are asking betray you must be from a sqlserver

 background.


> In Oracle a database definitely isn't the same as in sqlserver. In Oracle

> you should equate a sqlserver database with an Oracle schema.

>

> These issues are discussed in further detail in the Oracle concepts

 manual,


> which is online at http://technet.oracle.com

>

>

> Hth,

>

> Sybrand Bakker, Oracle DBA

>

> "Happy" <allan_at_livvy80.freeserve.co.uk> wrote in message

> news:97ubhr$ise$1_at_news8.svr.pol.co.uk...

> > Can anybody please tell me the relationship between installations,

 instances


> > and databases?

> > Is it 1 to 1 to 1?

> > Or can multiple databases be created from a single installation or

 instance?


> > Is an instance the same as an installation?

> > Is a database the same as an instance?

> > What defines them?

> >

> > ORACLE talk about a 'database system' comprising more than one database.

 Do


> > they mean

> > databases that have been created on the same node from different

> > installations?

> >

> > Thanks in advance

> > Allan

> >

> >

>

>