"；泄漏谓词”；错误

哇，我从没想过我会在谷歌上造成一个点击率为零的错误。

这是导致它的代码：

var otherSessions = 
db.ChildThing.Where(x => x.ID == thingOneID)
  .SelectMany(x => x.ParentThing.ChildThings.SelectMany(x2 => x.GrandchildThings))
  .Where(x=> x.Field1 == null)
  .ToList();

这里有一个例外：

System.Data.EntityCommandCompilationException：准备命令定义时出错。有关详细信息，请参阅内部异常。--->System.InvalidOperationException：内部.NET Framework数据提供程序错误1004，0，泄漏谓词。位于System.Data.Query.PlanCompiler.PlanCompiler.Assert（布尔条件，字符串消息）位于System.Data.Query.PlanCompiler.JoinGraph.RebuildNodeTreeForCrossJoins（AugmentedJoinNode joinNode）位于System.Data.Query.PlanCompiler.JoinGraph.RebuildNodeTree（AugmentedJoinNode joinNode，Dictionary 2& predicates) at System.Data.Query.PlanCompiler.JoinGraph.RebuildNodeTree(AugmentedNode augmentedNode, Dictionary 2&谓词）位于System.Data.Query.PlanCompiler.JoinGraph.RebuildNodeTree（AugmentedJoinNode，Dictionary 2& predicates) at System.Data.Query.PlanCompiler.JoinGraph.BuildNodeTree() at System.Data.Query.PlanCompiler.JoinGraph.DoJoinElimination(VarMap& varMap, Dictionary 2&processedNodes）位于System.Data.Query.PlanCompiler.JoinLimination.ProcessJoinGraph（节点joinNode）位于System.Data.Query.PlanCompiler.JoinLimination.VisitJoinPO（JoinBaseOp op，Node joinNode）位于System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.Visit(InnerJoinOp op, Node n) at System.Data.Query.InternalTrees.InnerJoinOp.Accept[TResultType](BasicOpVisitorOfT 1 v，节点n）位于System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.VisitNode(Node n) at System.Data.Query.InternalTrees.BasicOpVisitorOfNode.VisitChildren(Node n) at System.Data.Query.PlanCompiler.JoinElimination.VisitDefaultForAllNodes(Node n) at System.Data.Query.PlanCompiler.JoinElimination.VisitDefault(Node n) at System.Data.Query.InternalTrees.BasicOpVisitorOfNode.VisitRelOpDefault(RelOp op, Node n) at System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.访问（FilterOp-op，节点n）在System.Data.Query.InteralTrees.FilterOp.Accept[TResultType]（BasicOpVisitorOfT 1 v, Node n) at System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.VisitNode（节点n）位于System.Data.Query.InteralTrees.BasicOpVisitorOfNode.VisitChildren（节点n）位于System.Data.Query.PlanCompiler.JoinLimination.VisitDefaultForAllNodes（节点n）位于System.Data.Query.PlanCompiler.JoinLimination.VisitDefault（节点n）位于System.Data.Query.InteralTrees.BasicOpVisitorOfNode.VisitRlOpDefault（RelOp-op，Node n）位于System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.Visit(ProjectOp op, Node n) at System.Data.Query.InternalTrees.ProjectOp.Accept[TResultType](BasicOpVisitorOfT 1 v，节点n）位于System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.VisitNode(Node n) at System.Data.Query.InternalTrees.BasicOpVisitorOfNode.VisitChildren(Node n) at System.Data.Query.PlanCompiler.JoinElimination.VisitDefaultForAllNodes(Node n) at System.Data.Query.PlanCompiler.JoinElimination.VisitDefault(Node n) at System.Data.Query.InternalTrees.BasicOpVisitorOfNode.VisitPhysicalOpDefault(PhysicalOp op, Node n) at System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.访问（PhysicalProjectOp-op，节点n）在System.Data.Query.InteralTrees.PhysicalProjectOp.Accept[TResultType]（BasicOpVisitorOfT 1 v, Node n) at System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.VisitNode（节点n）位于System.Data.Query.PlanCompiler.JoinLimination.Process（）位于System.Data.Query.PlanCompiler.PlanCompiler.Compile（列出1& providerCommands, ColumnMap& resultColumnMap, Int32& columnCount, Set 1&entitySet）位于System.Data.EntityClient.EntityCommandDefinition.ctor（DbProviderFactory storeProviderFactory，DbCommandTree commandTree）---内部异常堆栈跟踪结束---位于System.Data.EntityClient.EntityCommandDefinition.ctor（DbProviderFactory storeProviderFactory，DbCommandTree commandTree）位于System.Data.EntityClient.EntityProviderServices.CreateCommandDefinition（DbProviderFactory storeProviderFactory，DbCommandTree commandTree）位于System.Data.EntityClient.EntityProviderServices.CreateDbCommandDefinition（DbProviderManifest providerManifest，DbCommandTree命令树）位于System.Data.Common.DbProviderServices.CreateCommandDefinition（DbCommandTree命令树）位于System.Data.Objects.Internal.ObjectQueryExecutionPlan.Prepare（ObjectContext上下文，DbQueryCommandTree树，Type elementType，MergeOption MergeOption，Span-Span，ReadOnlyCollection 1 compiledQueryParameters, AliasGenerator aliasGenerator) at System.Data.Objects.ELinq.ELinqQueryState.GetExecutionPlan(Nullable 1 for MergeOption）位于System.Data.Objects.ObjectQuery 1.GetResults(Nullable 1 for MergeOption）位于System.Data.Objects.ObjectQuery 1.System.Collections.Generic.IEnumerable<T>.GetEnumerator() at System.Collections.Generic.List 1..ctor（IEnumerable 1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable 1源）位于c:''src''MyProject''MyBL''UIEntities''UserSession.cs:line 130 中的MyProject.UIEntitys.UserSession.SaveReadingSession（UserSession uiEntity，MyEntities db）

那么，有什么我打破的想法吗？