PL/SQL getting error in user-defined exceptions in function

Question

In my PL/SQL program I created three exceptions: divide_by_zero, others and one user defined divide_by_one but my user defined exception doesn't work. I created a block statement to handle each exception but I am getting below error as shown in the screenshot. Can anyone help me to identify the issue ?

code:

CREATE OR REPLACE 
PACKAGE CALCULATOR AS 

FUNCTION DivNumber(divend IN Number, divend2 IN Number) RETURN NUMBER;

END CALCULATOR;
/

CREATE OR REPLACE
PACKAGE BODY CALCULATOR AS

FUNCTION DivNumber(divend IN Number, divend2 IN Number) RETURN NUMBER AS
 e_ZERO_DIVIDE EXCEPTION;

 BEGIN
-- the condition
  IF divend2 = 0 THEN 
    Raise e_ZERO_DIVIDE; 
  ELSIF divend2 = 1 THEN
    Raise one_divide;
  END IF;
  return divend / divend2;

--Exception handling  
EXCEPTION 
    WHEN e_ZERO_DIVIDE THEN
    dbms_output.put_line('Division by 0 or null');
    RETURN 1;

    WHEN one_divide THEN
    dbms_output.put_line('Division by 1 or null');
    RETURN NULL;

    WHEN OTHERS THEN
    dbms_output.put_line('ERROR: '||sqlerrm);
    RETURN 1;

 END DivNumber;

END CALCULATOR;
/

select calculator.DivNumber(12,1) from dual;

outout:

Answer 1

You need to declare one_divide of type Exception in the declare section, then only it will work.