C# 同一NHibernate Linq查询中的Cacheable（）、FetchMany（）和ToFuture（）

具有类似于以下示例的情况：

1个父实体

员工

有2个子集合：

地址

和

电话

我需要在

单程往返中检索所有地址和电话已初始化的员工，并使用
Cacheable（）
在二级缓存中缓存查询

使用：

var baseQuery = session
    .Query<Employee>()
    .Cacheable();

baseQuery
    .FetchMany(e => e.Addresses)
    .ToFuture();

var list = baseQuery
    .FetchMany(e => e.Phones)
    .ToFuture()
    .ToList();

信息：

Exception occurred getter of NHibernateTest.Objects.Entity`1[[System.Int32, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].Id

Object does not match target type.

堆栈跟踪：

at NHibernate.Properties.BasicPropertyAccessor.BasicGetter.Get(Object target) in p:\nhibernate-core\src\NHibernate\Properties\BasicPropertyAccessor.cs:line 213
at NHibernate.Tuple.Entity.AbstractEntityTuplizer.GetIdentifier(Object entity) in p:\nhibernate-core\src\NHibernate\Tuple\Entity\AbstractEntityTuplizer.cs:line 139
at NHibernate.Persister.Entity.AbstractEntityPersister.GetIdentifier(Object obj, EntityMode entityMode) in p:\nhibernate-core\src\NHibernate\Persister\Entity\AbstractEntityPersister.cs:line 3890
at NHibernate.Persister.Entity.AbstractEntityPersister.IsTransient(Object entity, ISessionImplementor session) in p:\nhibernate-core\src\NHibernate\Persister\Entity\AbstractEntityPersister.cs:line 3676
at NHibernate.Engine.ForeignKeys.IsTransient(String entityName, Object entity, Nullable`1 assumed, ISessionImplementor session) in p:\nhibernate-core\src\NHibernate\Engine\ForeignKeys.cs:line 194
at NHibernate.Engine.ForeignKeys.GetEntityIdentifierIfNotUnsaved(String entityName, Object entity, ISessionImplementor session) in p:\nhibernate-core\src\NHibernate\Engine\ForeignKeys.cs:line 250
at NHibernate.Type.ManyToOneType.Disassemble(Object value, ISessionImplementor session, Object owner) in p:\nhibernate-core\src\NHibernate\Type\ManyToOneType.cs:line 137
at NHibernate.Impl.MultipleQueriesCacheAssembler.Disassemble(Object value, ISessionImplementor session, Object owner) in p:\nhibernate-core\src\NHibernate\Impl\MultipleQueriesCacheAssembler.cs:line 33
at NHibernate.Cache.StandardQueryCache.Put(QueryKey key, ICacheAssembler[] returnTypes, IList result, Boolean isNaturalKeyLookup, ISessionImplementor session) in p:\nhibernate-core\src\NHibernate\Cache\StandardQueryCache.cs:line 74
at NHibernate.Impl.MultiQueryImpl.ListUsingQueryCache() in p:\nhibernate-core\src\NHibernate\Impl\MultiQueryImpl.cs:line 749
at NHibernate.Impl.MultiQueryImpl.List() in p:\nhibernate-core\src\NHibernate\Impl\MultiQueryImpl.cs:line 415
at NHibernate.Impl.FutureQueryBatch.GetResultsFrom(IMultiQuery multiApproach) in p:\nhibernate-core\src\NHibernate\Impl\FutureQueryBatch.cs:line 24
at NHibernate.Impl.FutureBatch`2.GetResults() in p:\nhibernate-core\src\NHibernate\Impl\FutureBatch.cs:line 73
at NHibernate.Impl.FutureBatch`2.get_Results() in p:\nhibernate-core\src\NHibernate\Impl\FutureBatch.cs:line 31
at NHibernate.Impl.FutureBatch`2.GetCurrentResult[TResult](Int32 currentIndex) in p:\nhibernate-core\src\NHibernate\Impl\FutureBatch.cs:line 79
at NHibernate.Impl.FutureBatch`2.<>c__DisplayClass4`1.<GetEnumerator>b__3() in p:\nhibernate-core\src\NHibernate\Impl\FutureBatch.cs:line 63
at NHibernate.Impl.DelayedEnumerator`1.<get_Enumerable>d__0.MoveNext() in p:\nhibernate-core\src\NHibernate\Impl\DelayedEnumerator.cs:line 26
at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
at Tests.Tests.CacheableFetchManyAndToFutureTest() in D:\somepath\Tests.cs:line 262

at System.Reflection.RuntimeMethodInfo.CheckConsistency(Object target)
at System.Reflection.RuntimeMethodInfo.InvokeArgumentsCheck(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at System.Reflection.RuntimePropertyInfo.GetValue(Object obj, Object[] index)
at NHibernate.Properties.BasicPropertyAccessor.BasicGetter.Get(Object target) in p:\nhibernate-core\src\NHibernate\Properties\BasicPropertyAccessor.cs:line 207

信息：

Exception occurred getter of NHibernateTest.Objects.Entity`1[[System.Int32, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].Id

Object does not match target type.

堆栈跟踪：

at NHibernate.Properties.BasicPropertyAccessor.BasicGetter.Get(Object target) in p:\nhibernate-core\src\NHibernate\Properties\BasicPropertyAccessor.cs:line 213
at NHibernate.Tuple.Entity.AbstractEntityTuplizer.GetIdentifier(Object entity) in p:\nhibernate-core\src\NHibernate\Tuple\Entity\AbstractEntityTuplizer.cs:line 139
at NHibernate.Persister.Entity.AbstractEntityPersister.GetIdentifier(Object obj, EntityMode entityMode) in p:\nhibernate-core\src\NHibernate\Persister\Entity\AbstractEntityPersister.cs:line 3890
at NHibernate.Persister.Entity.AbstractEntityPersister.IsTransient(Object entity, ISessionImplementor session) in p:\nhibernate-core\src\NHibernate\Persister\Entity\AbstractEntityPersister.cs:line 3676
at NHibernate.Engine.ForeignKeys.IsTransient(String entityName, Object entity, Nullable`1 assumed, ISessionImplementor session) in p:\nhibernate-core\src\NHibernate\Engine\ForeignKeys.cs:line 194
at NHibernate.Engine.ForeignKeys.GetEntityIdentifierIfNotUnsaved(String entityName, Object entity, ISessionImplementor session) in p:\nhibernate-core\src\NHibernate\Engine\ForeignKeys.cs:line 250
at NHibernate.Type.ManyToOneType.Disassemble(Object value, ISessionImplementor session, Object owner) in p:\nhibernate-core\src\NHibernate\Type\ManyToOneType.cs:line 137
at NHibernate.Impl.MultipleQueriesCacheAssembler.Disassemble(Object value, ISessionImplementor session, Object owner) in p:\nhibernate-core\src\NHibernate\Impl\MultipleQueriesCacheAssembler.cs:line 33
at NHibernate.Cache.StandardQueryCache.Put(QueryKey key, ICacheAssembler[] returnTypes, IList result, Boolean isNaturalKeyLookup, ISessionImplementor session) in p:\nhibernate-core\src\NHibernate\Cache\StandardQueryCache.cs:line 74
at NHibernate.Impl.MultiQueryImpl.ListUsingQueryCache() in p:\nhibernate-core\src\NHibernate\Impl\MultiQueryImpl.cs:line 749
at NHibernate.Impl.MultiQueryImpl.List() in p:\nhibernate-core\src\NHibernate\Impl\MultiQueryImpl.cs:line 415
at NHibernate.Impl.FutureQueryBatch.GetResultsFrom(IMultiQuery multiApproach) in p:\nhibernate-core\src\NHibernate\Impl\FutureQueryBatch.cs:line 24
at NHibernate.Impl.FutureBatch`2.GetResults() in p:\nhibernate-core\src\NHibernate\Impl\FutureBatch.cs:line 73
at NHibernate.Impl.FutureBatch`2.get_Results() in p:\nhibernate-core\src\NHibernate\Impl\FutureBatch.cs:line 31
at NHibernate.Impl.FutureBatch`2.GetCurrentResult[TResult](Int32 currentIndex) in p:\nhibernate-core\src\NHibernate\Impl\FutureBatch.cs:line 79
at NHibernate.Impl.FutureBatch`2.<>c__DisplayClass4`1.<GetEnumerator>b__3() in p:\nhibernate-core\src\NHibernate\Impl\FutureBatch.cs:line 63
at NHibernate.Impl.DelayedEnumerator`1.<get_Enumerable>d__0.MoveNext() in p:\nhibernate-core\src\NHibernate\Impl\DelayedEnumerator.cs:line 26
at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
at Tests.Tests.CacheableFetchManyAndToFutureTest() in D:\somepath\Tests.cs:line 262

at System.Reflection.RuntimeMethodInfo.CheckConsistency(Object target)
at System.Reflection.RuntimeMethodInfo.InvokeArgumentsCheck(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at System.Reflection.RuntimePropertyInfo.GetValue(Object obj, Object[] index)
at NHibernate.Properties.BasicPropertyAccessor.BasicGetter.Get(Object target) in p:\nhibernate-core\src\NHibernate\Properties\BasicPropertyAccessor.cs:line 207

按如下方式查询不起作用，因为它会生成一个笛卡尔积，这是无效的。如果有一名员工有两个地址和两个电话，数据库中每个唯一的地址和电话将在地址和电话集合中出现两次。在服务器上接收到结果后，将其区分开来并不是一个好的选择

var list = session
    .Query<Employee>()
    .FetchMany(e => e.Addresses)
    .FetchMany(e => e.Phones)
    .Cacheable()
    .ToList();

TLDR：如何检索在一次往返中初始化了地址和电话的所有员工，并将查询缓存在二级缓存中？谢谢你的回复
 我也有类似的问题——当第一次执行查询时，可缓存查询会返回许多笛卡尔乘积——也就是说，在查询缓存被命中之前……为什么要使用ToFuture（）呢这里？@Beatles1692没有使用ToFuture获取2个子集合，可以返回重复记录。据我所知，ToFuture只将查询标记为在已标记为ToFuture的其他查询中的单个批次中运行。我不认为它对返回的行数有任何影响。@Beatles1692如果您执行
session.Query（）.FetchMany（e=>e.Addresses）.FetchMany（e=>e.Phones）.ToList（）
则结果可能包含重复的地址/电话。通过使用to future，它们由不同的查询加载到代理中，因此不存在笛卡尔积问题。