Question

我正在使用NHibernate 3.0配置二级缓存。实体和集合的二级缓存效果很好但我也有一些实体具有过滤集合。

 <bag name="EntityTrans" cascade="all-delete-orphan" table="EntityTrans">
            <key column="entityId" not-null="true" />
            <one-to-many class="MyDomain.EntityTran, MyDomain" />
            <filter name="cultureFilter" condition=":cultureCode = CultureCode" />
        </bag>

NHibernate二级缓存不会缓存上面的过滤后的集合。我可以在NHProf中看到过滤的集合查询被发送到数据库。我的NHibernate配置文件包含以下条目。

<class-cache class="MyDomain.EntityTran, MuDomain" region="MyRegion" usage="read-only"/>
<collection-cache collection="MyDomain.Entity.EntityTrans" region="MyRegion" usage="read-only"/>

我是否需要添加更多内容来缓存已过滤的集合？

Answer 1

目前，NHibernate不支持过滤集合的二级缓存。

首先我找到了forum post。然后我查看了代码（CollectionLoadContext.cs ~line 299）并找到了以下内容：

if (!(session.EnabledFilters.Count == 0) && persister.IsAffectedByEnabledFilters(session))
{
    // some filters affecting the collection are enabled on the session, so do not do the put into the cache.
    log.Debug("Refusing to add to cache due to enabled filters");
    // todo : add the notion of enabled filters to the CacheKey to differentiate filtered collections from non-filtered;
    //      but CacheKey is currently used for both collections and entities; would ideally need to define two separate ones;
    //      currently this works in conjunction with the check on
    //      DefaultInitializeCollectionEventHandler.initializeCollectionFromCache() (which makes sure to not read from
    //      cache with enabled filters).
    return; // EARLY EXIT!!!!!
}

二级缓存不会缓存NHibernate中的过滤集合？

1 个答案: