NHibernate QueryOver distinct

Question

我有这个
设想:

class User
{
Id,
UserName
}

class UserRelationship
{
User GroupUser,
User MemberUser
}

and query

var query = QueryOver.Of<UserRelationship>()
.JoinqueryOver(x=>x.MemberUser)
.Where(x=>x.UserName == "TestUser");

现在我想返回 List Distinct User，所以我做不到

TransformUsing(Transformers.DistinctRootEntity)

因为这会给我 UserRelationship。

我需要这样的东西:

Select distinct user.ID 
from UserRelationship relationship
inner join User user on user.ID = relationship.MemberUser_ID

请帮忙
谢谢

Answer 1

鉴于类(class):

public class User
{
    public virtual int Id {get; set;}
    public virtual string UserName {get; set;}
}

public class UserRelationship
{
    public virtual int Id {get; set;}
    public virtual User GroupUser {get; set;}
    public virtual User MemberUser {get; set;}
}

以及流畅的映射:

public class UserMap : ClassMap<User>
{
    public UserMap()
    {
        Id(x=>x.Id).GeneratedBy.Native();
        Map(x=>x.UserName);
    }
}

public class UserRelationshipMap : ClassMap<UserRelationship>
{
    public UserRelationshipMap(){
        Id(x=>x.Id).GeneratedBy.Native();
        References(x=>x.GroupUser);
        References(x=>x.MemberUser);
    }
}

您想根据 UserRelationship 类中的“MemberUser”检索不同的“User”列表。

var distinctMemberUsers = QueryOver.Of<UserRelationship>()
    .Select(x => x.MemberUser.Id);

var users = QueryOver.Of<User>()
    .WithSubquery.WhereProperty(x=>x.Id).In(distinctMemberUsers)

这应该在 SQL 中使用 In 子句来为您提供一个不同的用户列表。