Hi Deepak,
There is no on-size-fits-all answer for you question. It very much depends on the shape and size of your data and which version of VI you are using.
If you are using a version prior to 10.6 there is no external documentation on tuning indexing, so advice would need to be sought through SAS support.
If you are using 10.6 then I recommend reading this section of the Admin Guide. Once you have read the documentation, please feel free to ask any further questions you have that are specific to your system.
Thanks,
Owain
... View more