Crystal Report Passing Parameter Value to other parameter

Hi,

I am trying to pass the parameter value to other parameter in Crystal Report.But i unable to do the same.

on below syntax i am unable to retrieve the item codes of selected item group.

The syntax given below,

It@Select * from OITB

Itc@Select * from OITM where itmsgrpcod='@It'

Regards,

Dhanraj Kotian.