SQL>
SQL> SET SERVEROUTPUT ON
SQL>
SQL>
SQL> DECLARE
2 v_true BOOLEAN := TRUE;
3 v_false BOOLEAN := FALSE;
4 v_null BOOLEAN := NULL;
5 BEGIN
6 IF v_true
7 THEN
8 DBMS_OUTPUT.PUT_LINE('true');
9 END IF;
10 IF v_false
11 THEN
12 DBMS_OUTPUT.PUT_LINE('false');
13 END IF;
14 IF v_null
15 THEN
16 DBMS_OUTPUT.PUT_LINE('null');
17 END IF;
18 END;
19 /
true
PL/SQL procedure successfully completed.
SQL>