Multiple Instances??

Can anyone explain to me how ORACLE handles multiple instances in relation to a single set of object code?

I am trying to install some upgrades to our application software and the vendor requires that the new upgrades be installed in a "staging" area. I then change my ORACLE_SID, apply the "schema" changes (grants, columns, etc) and then change my ORACLE_SID to do it all over again for our different instances (TRAINING, PRODUCTION, PRE-PRODUCTION) However, after I compile all the c and cobol routines, and then all the SQL forms and such, all the object code goes to the same file system. My question is, how does ORACLE know (or does it) which object code to apply to which instance, especially when I apply it to one instance at a time over a long period of time? If my training db is running one version of application software and the production db is running a different one, yet all the object code is in the same file system/directory, how can I be sure I am only applying the upgrade to only one instance?

If I have totally confused you and you still want to help me understand this, please send me e-mail to kcarmich_at_coco.cc.az.us! Any hints, criticisms, and arguments would be greatly appreciated! Received on Wed Sep 07 1994 - 21:40:36 CEST