Re: Study Q1: One Database Can Have Multiple Instances?

Hi

1.
Lets not get confused here!
multiple instances != parallel server (OPS) If you run OPS you have to instances on two servers, but you can also run to instances on one server. Why you ask? You might have a bunch of OLTP users which uses the same views and tables running on one instance. This would give you a high hitrate on the buffers in the SGA. Then you have some DDS users making big queries across lots of tables in a datawarehouse scenario. These queries would normally flush the buffercache which results in bad performance for the OLTP users. If thre DDS users have a instance on their own this might be best for every one. All it takes is a bit of extra memory ;-)
2.
Yes it would. Startup and shutdown would be more complicated - but we are all professionel and (should) know what we are doing, right? ;-) 3.
OPS works for all Enterprise editions

Hope these answers help you!
Lehmann

"Dino Hsu" <dino1_at_ms1.hinet.net> wrote in message news:8peqt3$cgl3d$1_at_ID-41926.news.cis.dfn.de...
> Dear All,
>
> The document mentions one database can have multiple instances (parallel
> server), but I have no experience of this setting, I wonder:
> 1.Why does one database need multiple instances at the same time?
> 2.Will it make the implementaion very complicated?
> 3.Is parallel server specific to Unix and doesn't work for Windows NT/2K?
> 4.Can you show me an implementation example, if it is useful?
>
> Thanks in advance.
> Dino
>
>
>
Received on Mon Sep 11 2000 - 03:56:18 CDT