Upgrade from 10g to 11g

For past few days, I was busy with critical upgrades of some mission critical databases from 10g to 11g. Apart from some minor issues, no performance issues have been reported post-upgrade. This should be a major relief for most of the customers planning to upgrade their system from 10g to 11g. Optimizer has not changed much between these two versions and therefore, unlike 9i to 10g, the upgrade from 10g to 11g should be smooth.

While comparing the Execution Plan of the critical queries during UAT testing, only one change observed is the introduction of Nested Loop Batching and this may change the plan hash value between the two versions. No performance degradation is observed with the introduction of NL Batching.

Post-Upgrade, it is now time to implement 11g new features and I may write on these, as and when, I have something interesting to share on these.