Re: Basic Oracle Concepts

1. No, it is not. One database means one instance, means one set of services. What you propose makes it impossible to run multiple databases *at the same time* using one instance. Running two databases at the same time requires 2 instances. Evidently you know sqlserver. A sqlserver database is more or less the same as an Oracle *schema*.
2. Multiple Oracle Homes are created during installation. Multiple Oracle Homes are typically used for
3. multiple different major releases of the same software
4. multiple different Oracle products

You would never ever create one home for each database, because the 2 homes will share exactly *nothing*, and you will run into an administration nightmare.
I admit we administrate a server where Oracle India installed Oracle 3 times on a single server in this fashion. The installations sucks!

As said before: you will rarely create multiple databases, because usually a different schema will do. If you setup your security appropiately, different schema's are completely separated. In your proposed configuration you are simply going to waste resources.

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Sybrand Bakker
Senior Oracle DBA