Reapply Optimizer Statistics
Reapply optimization statistics for each database. You can do this by either:
• Regenerating statistics from scratch.
If there is sufficient time, we recommend that you regenerate the optimizer statistics using the procedures of your application system.
• Using the statistics printed from the original installation in the step Print Optimizer Statistics earlier in this upgrade procedure.
If time is short, and if you printed the original statistics, you can read them back in with the –i option to optimizedb:
optimizedb dbname -i dbname.stats