Validación de Falso ó Verdadero de una manera inteligente

Set serveroutput on size 10000
SQL> 1 declare
variable boolean ;
v2 varchar2(2) :='S';
v4 varchar2(2);
v3 varchar2(10);
begin
v4 :='SI';
variable := variable
OR (v2='N')
OR (v4='NO');
IF variable = TRUE THEN v3:='TRUE'; ELSE v3:='FALSE'; END IF;
dbms_output.put_line(v3);
end;

SQL> /

FALSE
PL/SQL procedure successfully completed.

declare
variable boolean ;
v2 varchar2(2) :='N';
v4 varchar2(2);
v3 varchar2(10);
begin
v4 :='SI';
variable := variable
OR (v2='N')
OR (v4='NO');
IF variable = TRUE THEN v3:='TRUE'; ELSE v3:='FALSE'; END IF;
dbms_output.put_line(v3);
end;
/

TRUE

PL/SQL procedure successfully completed.