NHibernate 3 和未来的延迟加载

发布于 2024-11-08 19:58:38 字数 1431 浏览 0 评论 0原文

我有一个包含时间表集合的实体提醒（请参阅映射这里）。我不希望我的集合 Schedules 延迟加载，因此我将属性设置为 false：

<set access="field.pascalcase-underscore" cascade="all-delete-orphan" inverse="true" lazy="false" name="Schedules" mutable="true">
      <key foreign-key="FK_Schedules_Reminders">
        <column name="ReminderCode" />
      </key>
      <one-to-many class="ReminderSchedule" />
</set>

在一个查询中，我不想加载集合，因此我将 SetFetchMode 设置为 Lazy：

ICriteria FiltersCriteria = session.CreateCriteria<Domain.Reminder>();
FiltersCriteria.SetFetchMode("Schedules", FetchMode.Lazy);

运行我的查询，我注意到 Nhibernate 是运行提醒查询，然后，对于每个提醒，它运行单个查询来获取时间表。
这是我正在使用的代码：

ICriteria FiltersCriteria = session.CreateCriteria<Domain.Reminder>();
FiltersCriteria.SetFetchMode("Schedules", FetchMode.Lazy)
Result = FiltersCriteria.List<Domain.Reminder>();

经过一番努力，我使用 Future 更改了我的代码，一切正常：

ICriteria FiltersCriteria = session.CreateCriteria<Domain.Reminder>();
FiltersCriteria.SetFetchMode("Schedules", FetchMode.Lazy)
Result = FiltersCriteria
    .Future<Domain.Reminder>()
    .ToList<Domain.Reminder>();

为什么它不能简单地使用 FetchMode.Lazy 工作？为什么我必须使用未来？如果我在模式中设置惰性模式，显然，一切都会按我的预期进行。

谢谢。

原文

I've got an entity Reminder which contains a collection of Schedules (see the mapping here).
I didn't want my collection Schedules to be lazy loaded so I set the attribute to false:

<set access="field.pascalcase-underscore" cascade="all-delete-orphan" inverse="true" lazy="false" name="Schedules" mutable="true">
      <key foreign-key="FK_Schedules_Reminders">
        <column name="ReminderCode" />
      </key>
      <one-to-many class="ReminderSchedule" />
</set>

In one query I didn't want to load the collection so I've set the SetFetchMode to Lazy:

ICriteria FiltersCriteria = session.CreateCriteria<Domain.Reminder>();
FiltersCriteria.SetFetchMode("Schedules", FetchMode.Lazy);

Running my query I noticed that Nhibernate was running the query for the reminders and then, for each reminder, it was running single queries to fetch the Schedules.
Here is the code I was using:

ICriteria FiltersCriteria = session.CreateCriteria<Domain.Reminder>();
FiltersCriteria.SetFetchMode("Schedules", FetchMode.Lazy)
Result = FiltersCriteria.List<Domain.Reminder>();

After a little bit of struggle I've changed my code using the Future and everything worked fine:

ICriteria FiltersCriteria = session.CreateCriteria<Domain.Reminder>();
FiltersCriteria.SetFetchMode("Schedules", FetchMode.Lazy)
Result = FiltersCriteria
    .Future<Domain.Reminder>()
    .ToList<Domain.Reminder>();

Why doesn't it work simply using FetchMode.Lazy? Why do I have to use Future?
If I set the lazy mode in my schema, obviously, everything works as I would expect.

Thanks.

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