proc parametro if null

/** * 001 parameterModes */

CREATE OR REPLACE PROCEDURE ModeIn(p_parameter IN NUMBER) IS
  l_variable NUMBER := 0;

BEGIN

  DBMS_OUTPUT.PUT_LINE('Inside ModeIn:');

  IF p_parameter IS NULL THEN
    DBMS_OUTPUT.PUT_LINE('p_parameter is NULL');
  ELSE
    DBMS_OUTPUT.PUT_LINE('p_parameter = ' || p_parameter);
  END IF;
  
  l_variable := p_parameter;
  
  DBMS_OUTPUT.PUT_LINE('At end of ModeIn:');

 IF p_parameter IS NULL THEN
    DBMS_OUTPUT.PUT_LINE('p_parameter is NULL');
  ELSE
    DBMS_OUTPUT.PUT_LINE('p_parameter is =' || p_parameter);
  END IF;


END ModeIn;
/



/****  LLamando a la funcion ****/

SET SERVEROUTPUT ON

DECLARE
  l_in NUMBER := 1;
BEGIN
  DBMS_OUTPUT.PUT_LINE('Before calling ModeIn, l_In = ' || l_in);
  ModeIn(l_in);
  DBMS_OUTPUT.PUT_LINE('After calling ModeIn, l_in = ' || l_in);
END;
/


BEGIN
  ModeIn(3);
END;
/