Re: Are 5 Ora 7.3.3 Instances on 1 NT Box a good practice ?

I agree that you may want to have two databases in house, one for OLTP and one for DSS. Also, you could run these on the same machine to cut down on equipment costs. All though, would you really save that much in efficiency by taking the time to optimize one database for OLTP and one for DSS and then run them both on the same machine?!?

Also, I believe it is possible to create one database that has both OLTP and DSS components. As long as the OLTP and DSS parts of the database don't interact, there should not be a contention for resources. Add a few more processors and another disk controller in there, and you defiantly don't have a problem.

To shed some light onto why someone might have 5 instances running on one machine: [true story, and for the record, I was not involved]

Company X writes a client with a SQLServer back end. All the SQL in the client refers to tables directly, without reference to a schema (because that is how SQLServer is setup). Company X decides to run their client on oracle now and the only way to get it to work [they think] is to use public synonyms. So, each time they sell their service, it requires installing another database instance because you can't have two public synonyms with the same name.

All they needed to do was add

ALTER SESSION SET CURRENT_SCHEMA= some configurable parameter

at the begging of their code. But, because Company X didn't hire any Oracle people, just passed the responsibility to the most database savvy programmer...

• Paul

spencer wrote:

> I can think of a scenario in which you might want to run more
> than one instance of Oracle on a single machine. You might want
> to use one instance for 7x24 OLTP, and use the other instance as
> a "read only" data warehouse.
>
> By running two instances (two databases), you could administer
> each one independently. For example, using ARCHIVELOG mode for
> the active 7x24 online transaction database (where you don't
> want to lose any data) and NOARCHIVELOG mode for the "warehouse"
> database that is only loaded (updated) in batch.
>
> But running 5 nearly identical database instances on one small
> NT machine? I'm racking my brain, but I can't fathom the
> business goals, issues, constraints or requirements which led to
> that solution. I'm intrigued ! Availability? Security?
> Performance? Maybe someone else has an idea why you would need
> to run 5 instances on a single NT machine.
Received on Sun Jan 02 2000 - 23:11:20 CST