Re: More than one database on a system? Was: need advice on filesystem layout

In article <Pine.SUN.3.91.951110094053.8403A-100000_at_seatimes>, Steve Butler <sbut-is_at_seatimes.com> wrote:

> > Aren't all of these capabilities possible with running one database but
> > segregating applications to their own tablespaces? Maybe not with cold
> > backups but the other capabilities - restore and recover, move to another
> > box, should all be possible/not too complex with the one database scheme,
> > or no?
>
> It is possible to recover a portion of the database (as at the tablespace
> level), but certain failures will affect the entire database. With
> seperate instances on seperate spindles the interactions are minimized
> further.
>
> The "move to another box" should have included SPLITTING the applications
> to seperate boxes. Much easier to do when each is it's own database
> rather than just seperate tablespaces. The most flexible way is with
> seperate databases. It may actually reduce the administrative overhead.

We haven't made this move or configuration yet; I'm trying to ascertain the optimal way to set this up. Splitting the applications to seperate boxes is one thing we are going away from, to simplify management, and lessen costs - that's why we are moving from several boxes to one.

I never see much discussion or see anything written on using multiple databases Vs. one and I'm still feeling rather nebulous about it. I guess one thing that I can see is that if a drive goes bad and you have two or more databases all on seperate drives, only one db will be affected. Still, having the tablespaces on their own drives can restrict the down time to the affected application also, no?

-- 
Mike McCurdy    mccurdy_at_ucsvax.sdsu.edu
AIX/VMS System Management
Oracle Database Administration
University Computer Operations
San Diego State University