NHibernate SysCache不缓存子对象

时间:2015-04-16 07:20:01

标签: caching nhibernate syscache

希望得到您的帮助。 我有简单的主孩子集("播放器"和#34; playerChildObject")。获取"球员"还会抓住他们相关联的孩子。

SysCache会缓存玩家,但不会缓存儿童。

以下是对象(均使用Cache.ReadWrite()设置):

实体:

public class Player
{
    public virtual int Id { get; set; }
    public virtual string Name { get; set; }
    public virtual IList<PlayerChildObject> PlayerChildObjects { get; set; }

    public Player()
    {
        PlayerChildObjects = new List<PlayerChildObject>();
    }
}

public class PlayerChildObject
{
    public virtual int Id { get; protected set; }
    public virtual Player Player { get; set; }
}

映射:

public class PlayerMap : ClassMap<Player>
{
    public PlayerMap()
    {
        Id(x => x.Id).Column("id");
        Map(x => x.Name).Column("name");
        HasMany(x => x.PlayerChildObjects).KeyColumn("PlayerId")
            .Inverse()
            .Cascade.All()
            .Not.LazyLoad();
        Table("accounts");
        Cache.ReadWrite();
    }
}

public class PlayerChildObjectMap : ClassMap<PlayerChildObject>
{
    public PlayerChildObjectMap()
    {
        Id(x => x.Id).Column("id");
        References<Player>(x => x.Player, "playerId");
        Table("playerChildObjects");
        Cache.ReadWrite();
    }
}

会话工厂还使用&#34; UseQueryCache&#34;和&#34; UseSecondLevelCache&#34;:

Fluently.Configure()
.Database(MySQLConfiguration.Standard.ConnectionString(cs => ...))
.Cache(c => c.UseQueryCache().UseSecondLevelCache()
.ProviderClass(typeof (NHibernate.Caches.SysCache.SysCacheProvider).AssemblyQualifiedName))
.Mappings(m => m.FluentMappings.AddFromAssemblyOf<PlayerChildObjectMap>())
.BuildSessionFactory();

查询本身使用SetCacheable(true).SetCacheMode(CacheMode.Normal):

using (var session = SessionFactory.OpenSession())
{
    using (var transaction = session.BeginTransaction())
    {
        players = session.CreateCriteria(typeof(Player))
            .SetCacheable(true)
            .SetCacheMode(CacheMode.Normal)
            .List<Player>();
        transaction.Commit();
    }
}

然而,探查器显示玩家被缓存(仅被称为第一次执行玩家获取代码),而每次由PlayerID检索相同的PlayerChildObjects。

因此,第一个请求提供N + 1个DB调用(每个玩家的玩家列表+子对象),所有连续请求执行N个调用(每个玩家的子对象)。

我错过了什么? 如何让SysCache缓存儿童?

SysCache版本:3.1.0.4000

1 个答案:

答案 0 :(得分:2)

我想说,有两个问题。首先,即使 one-to-many HasMany也有缓存设置:

HasMany(x => x.PlayerChildObjects).KeyColumn("PlayerId")
    ...
    .Cache.IncludeAll() // or .IncludeNonLazy, .CustomInclude("customInclude")
        .ReadOnly() // or .NonStrictReadWrite(), .ReadWrite(), .Transactional(),
                    //  .CustomUsage("customUsage")        
        .Region("regionName");

检查更多邻近HasMany mapping here(Adam Bar关于按代码映射的文章,但最后是流利的)

文档19.2.1. Cache mappings

其次,我们应该使用批量获取:

public PlayerMap()
{
    BatchSize(25);

    HasMany(x => x.PlayerChildObjects).KeyColumn("PlayerId")
        ...
        .BatchSize(25)
...
public PlayerChildObjectMap()
{
    BatchSize(25);
    ...

在doc 19.1.5. Using batch fetching或此处了解更多相关信息: