Basic Oracle Concepts and Programming Question:

If you have an IN parameter, you can make it as an optional parameter for the calling statement by defining the formal parameter with the DEFAULT clause. This gives you the freedom of not providing the actual parameter when calling this procedure or function. See the following tutorial script shows you an example procedure with an optional parameter:

SQL> CREATE OR REPLACE PROCEDURE WELCOME AS
2 PROCEDURE GREETING(S IN CHAR DEFAULT 'globalguideline') AS
3 BEGIN
4 DBMS_OUTPUT.PUT_LINE('Welcome to ' || S);
5 END;
6 BEGIN
7 GREETING('MySpace.com');
8 GREETING;
9 END;
10 /
Procedure created.

SQL> EXECUTE WELCOME;
Welcome to MySpace.com
Welcome to globalguideline