06503. 00000 -  "PL/SQL: Function returned without value"
*Cause:    A call to PL/SQL function completed, but no RETURN statement was
           executed.

EXECUTE IMMEDIATE v_sql INTO v_valor;

  EXCEPTION
   WHEN NO_DATA_FOUND THEN v_valor:= 0 ;

return result;

-- In the loop
 CONTINUE WHEN v_valorNuevo = 0;