Composite Secondary Index- - response (1) by j355ga

Generally, the individual indices would be helpful for access and the optimizer might be able to do a bit map with them if they are weakly selective alone.
The 1 or 2 col index would be used for a covered query depending on your SQL.
The question you should ask is: do you even need a SI?  Does performance suffer without the index?  Do you need a covered query index for performance?  The SI uses system resources so if you don't need it don't create it.