SAP SuccessFactors Employee Central elements and fields are used to build the new hire’s profile and identify the internal hire and offboardee involved. The pieces of data that identify a new hire are the same data used for an employee's profile in Employee Central.
Since you’ve already collected data for existing employees, you don’t need to recollect this data like you would for a new hire. You only need to identify the specific data (HRIS fields) needed for Onboarding.
Because of the relationship between Onboarding and Employee Central, you can use some configurations and functions from Employee Central.