fluent-nhibernate - FluentNHibernate : Nested component mapping results in NHiberate QueryException

Question

嗨，我在 Nhibernate 中遇到映射问题。当我运行引用我的实体的组件类之一的 linq 查询时，我得到一个 QueryException，如下所示:

could not resolve property: ClosedCases of: Project.Entities.Headline

我有一张记录表，我想将这些记录映射到标题实体的多个对象中。

问题:

Is there something wrongly set up in my mapping?

我的 Headline实体被分成多个逻辑类，如下所示

  public class Headline:Entity
  {
    public virtual DateTime Date { get; set; }
    public virtual TeamTarget Teamtarget { get; set; }
  } 

 public class TeamTarget : Entity
  {
    public virtual DateTime FromDate { get; set; }
    public virtual DateTime ToDate { get; set; }
    public virtual TargetItem AchievedTarget { get; set; }
    public virtual Team Team { get; set; }
    }  

public class TargetItem : Entity
  {
    public virtual decimal ClosedCases { get; set; }
    public virtual decimal Invoicing { get; set; }
  }

映射文件:

  public class HeadlineMap: ClassMap<Headline>
  {
    public HeadlineMap()
    {
      Table("Headlines.Headlines");
      Id(x => x.Id).Column("HeadlinesId");
      Map(x => x.Date);
      Component(x => x.Teamtarget, t =>
      {
        t.References(x => x.Team).Column("TeamId").Cascade.None();
        t.Component(x => x.AchievedTarget, ti =>
        {
          ti.Map(x => x.Invoicing).Column("TeamInvoicing");
          ti.Map(x => x.ClosedCases).Column("TeamClosedCases");
        });
      });

我正在运行的 Linq 查询如下所示:

decimal closedCases = _headlineRepository.All
.Where(x =>
x.Date >= DateTimeExtensionMethods.FirstDayOfMonthFromDateTime(selectMonthFromDate)
&& x.Date <= DateTimeExtensionMethods.LastDayOfMonthFromDateTime(selectMonthFromDate)
&& x.Teamtarget.Team.Id == teamId
).Average(x => x.Teamtarget.AchievedTarget.ClosedCases);

我知道我可以通过团队 id 使用团队实体来访问标题项目，这有效，只是在实现目标的映射方面有问题。
有任何想法吗？

Answer 1

我认为你的映射很好。但据我所知，不可能使用 Linq to NHibernate 查询嵌套组件。它无法理解join要做什么，变得太复杂了。

我认为可以使用 NHibernate 3 的 QueryOver API 使用 JoinQueryOver 或 JoinAlias。你应该阅读这个:QueryOver in NH 3.0

也许这样的事情会起作用:

Headline headlineAlias = null;
TeamTarget targetAlias = null;
Team teamAlias = null;
TargetItem targetItemAlias = null;

var query = session.QueryOver<Headline>(() => headlineAlias)
                   .JoinAlias(() => headlineAlias.Teamtarget, () => targetAlias)
                   .JoinAlias(() => targetAlias.Team, () => teamAlias)
                   .JoinAlias(() => targetAlias.AchievedTarget, () => targetItemAlias)
                   .Where(x => x.Date >= DateTimeExtensionMethods.FirstDayOfMonthFromDateTime(selectMonthFromDate) && x.Date <= DateTimeExtensionMethods.LastDayOfMonthFromDateTime(selectMonthFromDate))
                   .And(() => teamAlias.Id == teamId)
                   .Select(Projections.Avg(() => targetItemAlias.ClosedCases))
                   .SingleOrDefault<decimal>();