Question

哇，我从未想过我会在Google上造成零点击的错误。

以下是导致它的代码：

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

这是例外：

System.Data.EntityCommandCompilationException：准备命令定义时发生错误。有关详细信息，请参阅内部异常---＆GT; System.InvalidOperationException：内部.NET Framework数据提供程序错误1004,0，泄漏谓词。 at System.Data.Query.PlanCompiler.PlanCompiler.Assert（布尔条件，字符串消息）在System.Data.Query.PlanCompiler.JoinGraph.RebuildNodeTreeForCrossJoins（AugmentedJoinNode joinNode）在System.Data.Query.PlanCompiler.JoinGraph.RebuildNodeTree（AugmentedJoinNode joinNode，Dictionary 2& predicates) at System.Data.Query.PlanCompiler.JoinGraph.RebuildNodeTree(AugmentedNode augmentedNode, Dictionary 2＆amp; predicates）在System.Data.Query.PlanCompiler.JoinGraph.RebuildNodeTree（AugmentedJoinNode joinNode，Dictionary 2& predicates) at System.Data.Query.PlanCompiler.JoinGraph.BuildNodeTree() at System.Data.Query.PlanCompiler.JoinGraph.DoJoinElimination(VarMap& varMap, Dictionary 2＆amp; processedNodes）在System.Data.Query.PlanCompiler.JoinElimination.ProcessJoinGraph（Node joinNode）在System.Data.Query.PlanCompiler.JoinElimination.VisitJoinOp（JoinBaseOp op，Node joinNode） at System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.Visit(InnerJoinOp op, Node n) at System.Data.Query.InternalTrees.InnerJoinOp.Accept[TResultType](BasicOpVisitorOfT 1 v，Node n）在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，Node n） at System.Data.Query.InternalTrees.FilterOp.Accept [TResultType]（BasicOpVisitorOfT 1 v, Node n) at System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.VisitNode（Node n）在System.Data.Query.InternalTrees.BasicOpVisitorOfNode.VisitChildren（Node n）在System.Data.Query.PlanCompiler.JoinElimination.VisitDefaultForAllNodes（Node n）在System.Data.Query.PlanCompiler.JoinElimination.VisitDefault（Node n）在System.Data.Query.InternalTrees.BasicOpVisitorOfNode.VisitRelOpDefault（RelOp op，Node n） at System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.Visit(ProjectOp op, Node n) at System.Data.Query.InternalTrees.ProjectOp.Accept[TResultType](BasicOpVisitorOfT 1 v，Node n）在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，Node n） at System.Data.Query.InternalTrees.PhysicalProjectOp.Accept [TResultType]（BasicOpVisitorOfT 1 v, Node n) at System.Data.Query.InternalTrees.BasicOpVisitorOfT 1.VisitNode（Node n）在System.Data.Query.PlanCompiler.JoinElimination.Process（）在System.Data.Query.PlanCompiler.PlanCompiler.Compile（List 1& providerCommands, ColumnMap& resultColumnMap, Int32& columnCount, Set 1＆amp; entitySets）在System.Data.EntityClient.EntityCommandDefinition..ctor（DbProviderFactory storeProviderFactory，DbCommandTree commandTree） ---内部异常堆栈跟踪结束--- 在System.Data.EntityClient.EntityCommandDefinition..ctor（DbProviderFactory storeProviderFactory，DbCommandTree commandTree）在System.Data.EntityClient.EntityProviderServices.CreateCommandDefinition（DbProviderFactory storeProviderFactory，DbCommandTree commandTree）在System.Data.EntityClient.EntityProviderServices.CreateDbCommandDefinition（DbProviderManifest providerManifest，DbCommandTree commandTree）在System.Data.Common.DbProviderServices.CreateCommandDefinition（DbCommandTree commandTree）在System.Data.Objects.Internal.ObjectQueryExecutionPlan.Prepare（ObjectContext context，DbQueryCommandTree tree，Type elementType，MergeOption mergeOption，Span span，ReadOnlyCollection 1 compiledQueryParameters, AliasGenerator aliasGenerator) at System.Data.Objects.ELinq.ELinqQueryState.GetExecutionPlan(Nullable 1 forMergeOption）在System.Data.Objects.ObjectQuery 1.GetResults(Nullable 1 forMergeOption）在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 source）在MyProject.UIEntities.UserSession.SaveReadingSession（UserSession uiEntity，MyEntities db）中的c：\ src \ MyProject \ MyBL \ UIEntities \ UserSession.cs：第130行

那么，我打破了什么想法？

Answer 1

哈，我在发帖时发现了答案！问题在于lambda ...SelectMany(x2 => x.GrandchildThings)...

当然，那应该是x2.GrandchildThings。问题解决了。

“泄漏谓词”错误？

1 个答案: