SET SERVEROUTPUT ON
DECLARE
    A NUMBER:=8;
    B NUMBER:=8;
    C NUMBER;
BEGIN
    IF A IS NULL OR B IS NULL THEN
        C :=9;
    ELSIF A > B THEN
        C :=9;
    ELSIF B = A THEN
        C :=10;
    END IF;
    DBMS_OUTPUT.PUT_LINE ( 'EL VALOR DE C ES ' || C);
  END;
/