MDS populate values in Name attribute which are in different attribute

Hi there,

I have one small Question I guess you guys can answer this  I hope I did create one Entity which isLinktable. Users would like to populate only  GroupCustName andRegion  attribute.

when we do domain based for CustomerGroup (MasterTable) it always look at either Name or Code but we are not populating Name or Code attribute

So I was trying to write business Rule for Name attribute like if users what ever they populate in theGroupCustName that should be in the Name attribute as well...

Can anyone help me how to write the business rule to populate Name attribute from GroupCustName attribute?

Thanks for your help in advance.