I just have basic question. Our team has upgraded our databases to 126.96.36.199. I have to come up with a plan for PSU patches and bug patches. We have upgraded our environment two months ago and now we are planing to apply patch on all environmenet (dev,uat,prod) ..... All I want to know that do I have to install only April 2013 PSU patches or should I have to apply 2013 january too. Do I have to apply other patches first before applying PSU patches?? .......... Also please let me know the difference between cpu or PSU patches??
All CPU/PSU patches are cumulative - so applying the latest one is sufficient. Pl also be aware that you need to choose a path - apply CPUs (now renamed to SPUs) or apply PSUs - once you apply a PSU, you cannot apply future CPUs - you have to continue to apply PSUs
Patch Set Updates for Oracle Products [ID 854428.1] - see section 9.1