How to fetch a many-to-many colletion?

[mynkow]

I have 3 tables, Groups, Users and Members. There are 2 entities, UserDto, GroupDto. I am trying to fetch/eager load the members if a group. The problem is that fetching is not working. What I am doing wrong?

MAPPING:

public class GroupDtoMap : DtoClassMap<GroupDto>
{
    public GroupDtoMap()
    {
        Id(g => g.Id, "group_id");
        HasManyToMany(g => g.Members) //  Members is a List<UserDto>
            .Table("members")
            .ParentKeyColumn("group_id")
            .ChildKeyColumn("user_id");
    }
}

QUERY:

var groups = ((DtoRepository<GroupDto>)repository).Session
                .CreateCriteria<GroupDto>("gr")
                    .Add(Expression.Eq("gr.IsActive", true))
                    .Add(Expression.IsNotNull("gr.Members.Id"))
                .SetFetchMode("gr.Members", NHibernate.FetchMode.Eager)
                .SetResultTransformer(new DistinctRootEntityResultTransformer())
                .Future<GroupDto>();
TEST: here isfetched is false

var isFetched = NHibernateUtil.IsInitialized(groups.First().Members);

[mynkow]

PS: I posted the wrong query. Here it is:

var groups = ((DtoRepository<GroupDto>)repository).Session
                .CreateCriteria<GroupDto>("gr")
                    .Add(Expression.Eq("gr.IsActive", true

))
                .CreateAlias("groups.Members", "member")
                    .Add(Expression.IsNotNull("member.Id"))
                .SetFetchMode("gr.Members", NHibernate.FetchMode.Eager)
                .SetResultTransformer(new DistinctRootEntityResultTransformer())
                .Future<GroupDto>();

[mynkow]

The same query with HQL has still property Members which is not initialized:

Session
                            .CreateQuery(@" select gr, member from GroupDto as gr
                                            inner join fetch Members as member
                                            where IsActive = true and member.Id != null ")
                            .SetResultTransformer(Transformers.DistinctRootEntity)
                            .Future<GroupDto>();

[Itzik Saban]

if you're using NHibernate 3.1+, then you can use QueryOver:

Session.QueryOver<GroupDTO>()

            .Where(x => x.IsActive == true)

            .JoinQueryOver<MemberDTO>(x => x.Members, NHibernate.SqlCommand.JoinType.InnerJoin) //or left join

            .Where(x => x.Id != null)

            .TransformUsing(Transformers.DistinctRootEntity)

            .Future<GroupDTO>();

2011/12/16 mynkow <myn...@gmail.com>

--
You received this message because you are subscribed to the Google Groups "nhusers" group.

To view this discussion on the web visit https://groups.google.com/d/msg/nhusers/-/uzulAPuJXxAJ.

To post to this group, send email to nhu...@googlegroups.com.
To unsubscribe from this group, send email to nhusers+u...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/nhusers?hl=en.

--

Itzik Saban

my blog

[mynkow]

Same result. The members collection is not initialized.