Consider

this function:

CREATE
OR REPLACE FUNCTION get_employee_fullname (
    p_emp_id IN NUMBER
)
RETURN VARCHAR2
IS
    v_fullname VARCHAR2(200);
BEGIN
    SELECT first_name || '-' || last_name
    INTO  
v_fullname
    FROM  
HR.employees
    WHERE 
employee_id = p_emp_id;
 
    RETURN v_fullname;
 
EXCEPTION
    WHEN NO_DATA_FOUND THEN
        RAISE_APPLICATION_ERROR(-20001, 'Employee not found for ID: ' || p_emp_id);
 
    WHEN OTHERS THEN
        RAISE_APPLICATION_ERROR(-20002, 'Unexpected error in get_employee_fullname: ' || SQLERRM);
END;
/

What is the output of this program given above table:

DECLARE
    v_name VARCHAR2(200);
BEGIN
    v_name := get_employee_fullname(-1);  
    DBMS_OUTPUT.put_line('Name: ' || v_name);
END;
/