java.sql.SQLException: The value supplied cannot be converted to DECIMAL 解决方法

SELECT  max(measure_time) as str2,avg(temperature) as stravg FROM weather_equipment_data_1 WHERE 1>0  AND MEASURE_TIME BETWEEN '2008-04-17 10:12:44' AND '2008-04-17 10:14:44'  group by ((DATEDIFF(second,'1970-01-01',MEASURE_TIME)-1) / 5) 

这段sql描述了按在这两个时间范围之内按5秒钟统计temperature平均值。
在sqlserver中运行一切正常。
但是在hibernate中执行Query query = session.createSQLQuery(sql)却报错为
java.sql.SQLException: The value supplied cannot be converted to DECIMAL

解决方法：

Query query = session.createSQLQuery(sql)
.addScalar("str2",Hibernate.STRING)
.addScalar("stravg",Hibernate.STRING);

将两个查询字段分别强制转为hibernate string之后运行正常。