Re: newbie: multiple databases

Kim Wykoff wrote:
>
> Coming from a Sybase background, I find Oracle really hard to grasp.
>
> I'm trying to set up three different databases on one host. I want them
> all to be accessible and running at all times.
>
> In Sybase this would be very easy because there is just one database
> server in which I create the three databases. As long as the server
> were running, I would be able to access any database I wanted or all
> three simultaneously.
>
> With Oracle it seems that only one database can be running at any one
> time within one "server" or "instance". So does that mean that I must
> have 3 servers running? And how do I create these other servers? Do I
> have to install each server or is there an easy way to replicate the
> servers?
>
> I don't understand Oracle's concept of a database server even though
> I've been reading the dba handbook on the architecture. Maybe it's
> because I keep trying to relate it to Sybase and it doesn't fit.
>
> Help would be much appreciated. Thank you,
>
> kimWhat you are referring to are instances. A server is more like hardware
or host. Each of the instances run off of the same software (oracle), however they are each separate entities. In order to create a new instance, you can do it several ways. One is by using the oracle installer. I don't recommend this methodology because is takes the defaults associated with that particular operating system, the block size in particular. In addition, it doesn't let you really understand how the database is being built and what it takes to build one. I recommend that you do this by hand. Since you are new, please be sure to do a complete backup of your databases prior to building new ones. The steps are relatively easy and can be found in your DBA handbook. By doing it via a script, you can repeatively use this to easily recreate or create new databases (instances).
Hope this helps

-- 
Sheilah Scheurich
DBA

My opinions are my own and not that of my 
employer.

To respond via email, remove underscores.