Nhibernate Parent Child没有得到子列表

Question

我有一个对象“位置”，它有一个子位置列表。 我的对象和映射看起来像这样

    private int _id;
    private string _name;
    private IList<Location> _subLocations;
    private IList<Stock> _stockList;
    private Location _parent;
    private bool _isActive;
    private bool _recommend;

    public virtual IList<Location> SubLocations
    {
        get
        {
            if (_subLocations == null)
            {
                _subLocations = new List<Location>();
            }

            return _subLocations;
        }
        set
        {
            _subLocations = value;
            OnPropertyChanged("SubLocations");
        }
    }

    // more properties ...

我的映射如下所示：

public class LocationMap:ClassMap<Location>
{
    public LocationMap()
    {
        Id(x => x.Id);
        Map(x => x.Name);
        Map(x => x.IsActive);
        References(x => x.Parent);

        HasMany(x => x.SubLocations).Where(x => x.IsActive == true);
        HasMany(x => x.StockList).Where(x => x.IsActive == true);            

        Table("tbl_locations");

    }
}

我也 100% 确定位置对象具有 IsActive = true

但是当我得到一个 Location 对象时，SubLocations 列表总是空的。有人知道这是如何表现的吗？或者有什么想法可以调试这样的问题？

编辑 我的数据库如下所示：

   Id   Name          IsActive  Parent_id
   1    Magazijn A       1     NULL
   2    Magazijn B       1     NULL
   3    Gang A           1      2
   4    Rek B            1          3

查询 这是我获取所有父位置的查询

    public IList<Location> GetAllParentLocations()
    {
        var result = NHibernateHelper.Session.CreateQuery("from Location l fetch all properties where l.Parent is null and l.IsActive = true").List<Location>();
        return (List<Location>)result ?? new List<Location>();
    }

生成的 SQL

      NHibernate: select location0_.Id as Id15_, location0_.Name as Name15_,  location0_.IsActive as IsActive15_, location0_.Parent_id as Parent4_15_ from tbl_locations location0_ where (location0_.Parent_id is null) and location0_.IsActive=1
NHibernate: SELECT sublocatio0_.Location_id as Location5_1_, sublocatio0_.Id as Id1_, sublocatio0_.Id as Id15_0_, sublocatio0_.Name as Name15_0_, sublocatio0_.IsActive as IsActive15_0_, sublocatio0_.Parent_id as Parent4_15_0_ FROM tbl_locations sublocatio0_ WHERE  (sublocatio0_.IsActive = 1) and sublocatio0_.Location_id=@p0;@p0 = 1 [Type: Int32 (0)]
         NHibernate: SELECT sublocatio0_.Location_id as Location5_1_, sublocatio0_.Id as Id1_, sublocatio0_.Id as Id15_0_, sublocatio0_.Name as Name15_0_, sublocatio0_.IsActive as IsActive15_0_, sublocatio0_.Parent_id as Parent4_15_0_ FROM tbl_locations sublocatio0_ WHERE  (sublocatio0_.IsActive = 1) and sublocatio0_.Location_id=@p0;@p0 = 42 [Type: Int32 (0)]
NHibernate: SELECT sublocatio0_.Location_id as Location5_1_, sublocatio0_.Id as Id1_, sublocatio0_.Id as Id15_0_, sublocatio0_.Name as Name15_0_, sublocatio0_.IsActive as IsActive15_0_, sublocatio0_.Parent_id as Parent4_15_0_ FROM tbl_locations sublocatio0_ WHERE  (sublocatio0_.IsActive = 1) and sublocatio0_.Location_id=@p0;@p0 = 60 [Type: Int32 (0)]

在查询中，它对“Location_id”列执行 where 子句。但它必须使用 Parent_id 列。不确定这个 Location_id 列来自哪里...

Answer 1

您是否关闭了延迟加载？我建议你看看这个关于延迟加载的链接Is Lazy Loading required for nHibernate?

Answer 2

以下链接解决了我的问题：

Fluent NHibernate HasMany Foreign Key Mapping Problem

我已将映射更改为：

HasMany(x => x.SubLocations).KeyColumns.Add("Parent_Id").Where(x => x.IsActive == true);