Java Resultset映射返回null，SQL语句不'；T

我有这样一个SQL语句：

SELECT generatedresult,sum(size) as count  FROM table1_detail AS w WHERE date > '2011.06.01' AND w.l_date < '2011.06.02'  GROUP BY category ORDER BY count  desc ; 

@Entity
@Stateless
@Cache(type = CacheType.NONE, alwaysRefresh=true, shared=false, expiry=1, size=0)
@Cacheable(false)
@SqlResultSetMappings({
    @SqlResultSetMapping(name = "ResultMapping",
    entities = {
        @EntityResult(entityClass = ResultMap.class,
        fields = {
            @FieldResult(name = "generatedresult", column = "generatedresult"),
            @FieldResult(name = "count", column = "count")
        })})
})

当我为此查询编写resultset映射时，如下所示：

SELECT generatedresult,sum(size) as count  FROM table1_detail AS w WHERE date > '2011.06.01' AND w.l_date < '2011.06.02'  GROUP BY category ORDER BY count  desc ; 

@Entity
@Stateless
@Cache(type = CacheType.NONE, alwaysRefresh=true, shared=false, expiry=1, size=0)
@Cacheable(false)
@SqlResultSetMappings({
    @SqlResultSetMapping(name = "ResultMapping",
    entities = {
        @EntityResult(entityClass = ResultMap.class,
        fields = {
            @FieldResult(name = "generatedresult", column = "generatedresult"),
            @FieldResult(name = "count", column = "count")
        })})
})

---

在另一个类中使用它，我得到了空结果。有人对这个问题有什么看法吗？

我猜一猜，因为我对resultset映射了解不多。但是从您的SQL看来，您选择了总和作为计数，但是在映射中，您实际上是在寻找一个名为count的列。您好，这就是它在resultmapping中的用法。您可以在sql中随意命名列，然后在resultmapping中以这种方式调用它。无论如何，谢谢你的评论。