I am planning to upgrade a db from 10g to 11g. I am making a rough estimate of the timing for this.
I want to clarify few things:
1. Does upgrade invalidates all objects (ie user and dict) and then Validates them ?
2. Does the statistics in 10g usable in 11g ? Do we need to collect fresh stats (for both user and dict tables)
Pl identify exact versions of "10g" and "11g".
The upgrade process will invalidate all objects - post upgrade process will recompile all the invalids.
Statistics will need to be gathered before the upgrade and after. 11g stats are different than 10g stats.
1.- You need to verfiy that there are no invalid objects prior to your upgrade, especially with the sys/system users
2.-Yes dictionay stats will need to be taken, this is where RAT, SPA and SQL Plan Baselines come in, so that you can plan and detect where after your upgrade your sqls will have a degrade in performance and be able to plan and attack it