nhibernate：为什么 nhibernate 会更新我的子实体的外键？

Question

好的，我有两个名为 WorkPostSheet 和 WorkPost 的实体，其中 WorkPostSheet 包含 WorkPost-items 的集合：

public class WorkPostSheet
{
    ...

    public virtual IEnumerable<WorkPost> WorkPosts
    {
        get;
        private set;
    }
}

在我的集成测试中，我注意到 nhibernate 创建了一个我无法理解的更新语句。测试：

    [Test]
    public void Commit_CreateNewWorkPostSheetWithWorkPosts_WorkPostsPersisted()
    {
        using (IUnitOfWork unitOfWork = IsolatingFactory.CreateReadOnlyUnitOfWork())
        {
            // arrange
            WorkPostSheetRepository repository = new WorkPostSheetRepository(IsolatingFactory);
            WorkItemRepository workItemRepository = new WorkItemRepository(IsolatingFactory);

            DateTime from = new DateTime(2000, 1, 1);
            DateTime to = new DateTime(2000, 2, 1);
            WorkPostSheet sheetWithWorkPosts = WorkPostSheet.Create(TestData.CreateAndCommitUser("min", "Marius", "Ingjer", IsolatingFactory), new TimePeriod(from, to));

            WorkItem workItemToPostWorkOn = WorkItem.Create(0, "A");
            workItemRepository.Commit(workItemToPostWorkOn);

            WorkPost workPost = sheetWithWorkPosts.Add(workItemToPostWorkOn, from);

            // act
            repository.Commit(sheetWithWorkPosts);
            unitOfWork.Session.Flush();
            unitOfWork.Session.Clear();

            WorkPostSheet sheetWithWorkPostsFromDb = repository.Get(sheetWithWorkPosts.Id, false);

            // assert
            CollectionAssert.Contains(sheetWithWorkPostsFromDb.WorkPosts, workPost);
        }
    }

输出：

NHibernate：插入“用户”（用户名、名字、姓氏）值（@p0、@p1、@p2）；选择last_insert_rowid();@p0 = 'min', @p1 = 'Marius', @p2 = 'Ingjer'

这很有意义，因为我正在创建一个用户 (TestData.CreateAndCommitUser)

NHibernate：插入“WorkItem”（LastChanged、描述、Id）值（@p0、@p1、@p2）；@p0 = 06.01.2010 21:50:25、@p1 = 'A'、@p2 = 0

这有意义，因为我正在创建一个工作项

NHibernate：插入“WorkPostSheet”（PeriodFrom、PeriodTo、userId）值（@p0、@p1、@p2）；选择last_insert_rowid();@p0 = 01.01.2000 00:00:00, @p1 = 01.02.2000 00:00:00, @p2 = 1

这是有道理的，因为我正在创建工作表

NHibernate：插入“WorkPost”（WorkDone、workItemId、sheetId）值（@p0、@p1、@p2）；选择last_insert_rowid();@p0 = 0，@p1 = 0，@p2 = 1

这是在 WorkPostRepository 中提交的（工作表是根实体）

NHibernate：更新“WorkPost”SETsheetId = @p0 WHERE Id = @p1;@p0 = 1，@p1 = 1

现在这个我不明白。外部会使用首次提交实体时分配的相同值进行更新。你能帮我理解这一点吗？

NHibernate：选择workpostsh0_.Id作为Id3_1_，workpostsh0_.PeriodFrom作为PeriodFrom3_1_，workpostsh0_.PeriodTo作为PeriodTo3_1_，workpostsh0_.userId作为userId3_1_，user1_.Id作为Id0_0_，user1_.UserName作为UserName0_0_，user1_.FirstName作为FirstName0_0_，user1_。 LastName as LastName0_0_ FROM "WorkPostSheet" workpostsh0_ inside join "User" user1_ on workpostsh0_.userId=user1_.Id WHERE workpostsh0_.Id=@p0;@p0 = 1

从存储库加载

NHibernate：选择workposts0_.sheetId作为sheetId2_，workposts0_.Id作为Id2_，workposts0_.Id作为Id2_1_，workposts0_.WorkDone作为WorkDone2_1_，workposts0_.workItemId作为workItemId2_1_，workposts0_.sheetId作为sheetId2_1_，workitem1_.Id作为Id1_0_， _。 LastChanged 为 LastChan2_1_0_，workitem1_.Description 为 Descript3_1_0_ FROM“WorkPost”workposts0_ 在 workposts0_.workItemId=workitem1_.Id 上内部加入“WorkItem”workitem1_，其中 workposts0_.sheetId=@p0;@p0 = 1

延迟加载

以下是映射文件：

sealed class WorkPostClassMap : ClassMap<WorkPost>
{
    public WorkPostClassMap()
    {
        Not.LazyLoad();

        Id(post => post.Id).GeneratedBy.Identity().UnsavedValue(0);
        Map(post => post.WorkDone);
        References(post => post.Item).Column("workItemId").Not.Nullable();
        References(Reveal.Property<WorkPost, WorkPostSheet>("Owner"), "sheetId").Not.Nullable();
    }
}

sealed class WorkPostSheetClassMap : ClassMap<WorkPostSheet>
{
    public WorkPostSheetClassMap()
    {
        Id(sheet => sheet.Id).GeneratedBy.Identity().UnsavedValue(0);
        Component(sheet => sheet.Period, period =>
                                             {
                                                 period.Map(p => p.From, "PeriodFrom");
                                                 period.Map(p => p.To, "PeriodTo");
                                             });
        References(sheet => sheet.Owner, "userId").Not.Nullable();
        HasMany(sheet => sheet.WorkPosts).KeyColumn("sheetId").AsBag();
    }
}

Answer 1

您是否将关联的收集端的“inverse”属性设置为“true”？

请参阅：http://ayende.com/Blog/archive/2009/01/18/nh-prof-new-feature-superfluous-ltmany-to-onegt-update.aspx