Bind Callout to Column 

To run callout method, you have to bind a Callout method with a column. 

For example, here we bind callout method to column VAT_BasicSalary and VAT_HRA. Full name of callout method with namespace of above class is VAT.Model.CalloutEmployeeSalary.netSalary. 

So,Login with SystemAdministration Role 

Open Window ->Table and Column, Find DB Table Name record VAT_Employee 

Go to third tab Column, Find the DB Column Namerecord VAT_BasicSalay 

Set Callout checkbox to True 

Set Callout Code to ‘VAT.Model.CalloutEmployeeSalary.netSalary’ (As Show in Below Pic) 

Same done for other column VAT_HRA