org.hibernate.MappingException: No Dialect mapping for JDBC type: -9

解決方式就是要指定回傳值的型態，例如：

    String stSQL = "SELECT MAX(id) AS serial_number FROM your_table WHERE TO_NUMBER(id)>20120101 AND TO_NUMBER(id)<20121231;
    List<?> serialNumberList = (List<?>)this.getSessionFactory().getCurrentSession().createSQLQuery(stSQL)
                                                              .addScalar("serial_number", new org.hibernate.type.StringType()).list();