hibernate - 如何实现 Subqueries.rowCount(DetachedCriteria dc)

Question

当 DetachedCrieria 有投影时，如何获取 DetachedCriteria 结果集的行数？对于 HQL：

select count(*) from (select name, sum(grade) from score group by name)。

对于hibernate，如何实现Subqueries.rowCount(DetachedCriteria dc)？谢谢。

Answer 1

如果你想要的只是计数，为什么不直接执行

select count(name) from score group by name

Answer 2

我有同样的问题......我想出了以下解决方案并且它有效：

myCriteria.setProjection(Projections.sqlProjection("count(*) as count from ( select distinct id , {alias}.enteredDate  ", new String[] { "count" }, new Type[] { StandardBasicTypes.LONG }));

// this is needed to close the parentheses opened in the Projection
myCriteria.add(Restrictions.sqlRestriction(" 1=1)"));