nhibernate - QueryOver 或与子查询

Question

我有以下使用子查询的 NHibernate 查询:

NHContext.Session.QueryOver<Item>()
            .WithSubquery.WhereProperty(x => x.ItemId).In(QueryOver.Of<Foo>().Where(x => x.AFlag).Select(x => x.ItemId))
            .WithSubquery.WhereProperty(x => x.ItemId).In(QueryOver.Of<Bar>().Where(x => x.AFlag).Select(x => x.Item))  
            .Future<Item>();

这将运行以下 SQL:

SELECT *
FROM   item this_
WHERE  this_.ItemId in (SELECT this_0_.ItemId as y0_
                            FROM   Foo this_0_
                            WHERE  this_0_.AFlag = 1 /* @p0 */)
and    this_.ItemId in (SELECT this_0_.ItemId as y0_
                            FROM   Bar this_0_
                            WHERE  this_0_.AFlag = 1 /* @p0 */)

我希望它使用 或 所以例如:

SELECT *
FROM   item this_
WHERE  this_.ItemId in (SELECT this_0_.ItemId as y0_
                            FROM   Foo this_0_
                            WHERE  this_0_.AFlag = 1 /* @p0 */)
or   this_.ItemId in (SELECT this_0_.ItemId as y0_
                            FROM   Bar this_0_
                            WHERE  this_0_.AFlag = 1 /* @p0 */)

我知道我可以通过执行以下操作在 Criteria 中做到这一点:

var disjunction = new Disjunction();
disjunction.Add(Subqueries.PropertyIn("ItemId", 
     DetachedCriteria.For<Foo>()
     .SetProjection(Projections.Property("ItemId"))
     .Add(Restrictions.Eq("AFlag", 1))
));

但是想知道是否有一种更简单的方法可以通过 QueryOver 来实现，并避免使用字符串作为属性名称。

谢谢你的帮助。

Answer 1

对于不太常见的析取(或)，我认为您需要使用 Subqueries.WhereProperty<>而不是 WithSubquery

Session.QueryOver<Item>()
    .Where(Restrictions.Disjunction()
        .Add(Subqueries.WhereProperty<Item>(x => x.ItemId).In(QueryOver.Of<Foo>().Where(x => x.AFlag).Select(x => x.ItemId)))
        .Add(Subqueries.WhereProperty<Item>(x => x.ItemId).In(QueryOver.Of<Bar>().Where(x => x.AFlag).Select(x => x.Item))))
    .Future<Item>();