我正在尝试使用 NHibernate 的 Criteria API 来编写与此等效的内容:
select foo_id from foo_history
group by foo_id
having sum(bar_in) > 0 or sum(baz_in) > 0;
使用此映射:
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="MVC"
namespace="MVC.Model.Things">
<class name="MVC.Model.Things.FooHistory, MVC"
table="foo_history">
<id name="ID" column="foo_hist_id" type="guid"
unsaved-value="00000000-0000-0000-0000-000000000000">
<generator class="guid.comb" />
</id>
<!-- Properties -->
<property name="BarIn" column="bar_in" type="decimal"
precision="19" scale="4" not-null="true" />
<property name="BazIn" column="baz_in" type="decimal"
precision="19" scale="4" not-null="false" />
<!-- Foreign Keys -->
<many-to-one name="Foo" column="foo_id"
class="MVC.Model.Things.Foo, MVC.Model.Things"
not-null="true" />
</class>
</hibernate-mapping>
和这个标准代码(分离,因为它将是一个子查询):
var results = DetachedCriteria.For<FooHistory>("fh")
.SetProjection(Projections.ProjectionList()
.Add(Projections.GroupProperty(Projections.Id()))
.Add(Projections.Sum("fh.BarIn"))
.Add(Projections.Sum("fh.BazIn")))
.Add(Restrictions.Gt(Projections.Sum("fh.BarIn"), 0) ||
Restrictions.Gt(Projections.Sum("fh.BazIn"), 0))
.GetExecutableCriteria(session).List();
SetProjection()
问题是在 NHibernate 生成无效 MySQL的结果之后添加条件限制:
SELECT this_.foo_hist_id as y0_,
sum(this_.bar_in) as y1_,
sum(this_.baz_in) as y2_
FROM foo_history this_
WHERE (sum(this_.bar_in) > ?p0
or sum(this_.baz_in) > ?p1)
GROUP BY this_.foo_hist_id
...使用 WHERE 而不是 HAVING。使用单个限制可以正常工作,并且一切都是正确的。我假设由于 HN-1280(“向 CreateCriteria 查询添加 HAVING 支持,修复参数顺序错误”)这是可能的,但我没有使用正确的“OR”语言(例如,Restrictions.Disjunction()
总是创建 WHERE)。
这可能吗?