The Intelligence page on the Optimization tab of the Preferences window allows you to select your optimization intelligence settings.
Optimization intelligence settings enables you to either choose the settings used during optimization or allows you to select the predefined "Intelligence Level" settings.
Customize the settings on the Optimization, Forces, and Quota pages.
Use the predefined optimization intelligence levels. The items selected on the Forces and Quota pages and the Temp table generation option on the Optimization page change according to the level selected. Levels range from 0 to 10. The higher the level the more intelligent the SQL Optimizer is and the more likely of finding a better SQL alternative.
The Abstract Plan settings on the Abstract Plan page and the Join table and Advanced SQL transformation options on the Optimization page is adjusted independent of the optimization intelligence level.