BAPI_EMPLOYEE_CHECKEXISTENCE

DATA ls_return TYPE bapireturn.

CALL FUNCTION 'BAPI_EMPLOYEE_CHECKEXISTENCE'
  EXPORTING
    number = 99999999
  IMPORTING
    return = ls_return.
IF ls_return-type = 'E'.
  MESSAGE ls_return-message TYPE ls_return-type.
ENDIF.

On newer systems there is also class CL_HRPA_MAINTAIN_EMPLOYEE with method PERSONNEL_NUMBER_EXISTS.
Or class CL_HRPA_MAINTAIN_EMPLOYEE_UTIL and method EXIST_EMPLOYEE.

Tag: BAPI_EMPLOYEE_CHECKEXISTENCE

[ABAP] Validate pernr