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RE: two databases in a server

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Date: Thu, 30 Mar 2006 13:04:00 -0600
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We do have several applications that share an instance, but that's because those apps generally are related (e.g. data from one app schema needed in another). But I don't see any benefit of merging unrelated apps with distinctly different data and access methods (e.g. data entry vs. DSS/query vs. automated data collection). I'd think off-hand that it would make that one monolithic instance much more difficult to manage than several smaller ones (shared_pool flogging comes to mind).

And I think the need to migrate the apps to another instance for app-specific version upgrades has already been mentioned.

My $.02,

-----Original Message-----
[] On Behalf Of Ric Van Dyke Sent: Thursday, March 30, 2006 12:05 PM
To:; David Sharples
Cc: Oracle-L_at_Freelists. Org (E-mail)
Subject: RE: two databases in a server

Generally it's bad because there is a certain level of resource consumption for an instance of any size. So pay the price ONCE and have an instance large enough to do all the work needed by all the applications using the database. There can be cases where multiple instances on the same box are needed, but many cases that I have seen it was not needed. Many times folks can use one instance (or at least fewer instances) to get the work done.

Ric Van Dyke
Hotsos Enterprises

Hotsos Symposium, be there:

-----Original Message-----
[] On Behalf Of Tom Fox Sent: Thursday, March 30, 2006 12:53 PM
To: David Sharples
Cc:; Oracle-L_at_Freelists. Org (E-mail) Subject: Re: two databases in a server

I've heard the argument before about having more than one instance on a machine is a bad idea.

However, on the flip side, having 50 applications share one instance can

be bad, as if one app needs a particular patch, you're affecting 49 other
applications due to one application's requirements.

Anyone care to elaborate why more than one instance is bad?


On Thu, 30 Mar 2006, David Sharples wrote:

> by joining them into a single instance - that is best practise


Received on Thu Mar 30 2006 - 13:04:00 CST

Original text of this message