SQL语句的某些部分嵌套太深。 重写查询或将其分解为较小的查询

我在我的控制器中有动作调用以下方法：

public IQueryable getcontactinfo(long[] id) { var organizationsiteids = from accountsitemapping in entities.AccountSiteMappings where id.Any(accountid => accountsitemapping.ACCOUNTID == accountid) select accountsitemapping.SITEID; var usersdepts = from userdept in entities.UserDepartments join deptdefinition in entities.DepartmentDefinitions on userdept.DEPTID equals deptdefinition.DEPTID where organizationsiteids.Any(accountid => deptdefinition.SITEID == accountid) select userdept; var contactsinfos = from userdept in usersdepts join contactinfo in entities.AaaUserContactInfoes on userdept.USERID equals contactinfo.USER_ID select contactinfo; return contactsinfos; } 

但是当我运行应用程序并导航到action方法时，将在视图级别上引发以下错误： –

 System.Data.EntityCommandExecutionException was unhandled by user code HResult=-2146232004 Message=An error occurred while executing the command definition. See the inner exception for details. Source=System.Data.Entity StackTrace: at System.Data.EntityClient.EntityCommandDefinition.ExecuteStoreCommands(EntityCommand entityCommand, CommandBehavior behavior) at System.Data.Objects.Internal.ObjectQueryExecutionPlan.Execute[TResultType](ObjectContext context, ObjectParameterCollection parameterValues) at System.Data.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption) at System.Data.Objects.ObjectQuery`1.System.Collections.Generic.IEnumerable.GetEnumerator() at System.Data.Entity.Internal.Linq.InternalQuery`1.GetEnumerator() at System.Data.Entity.Infrastructure.DbQuery`1.System.Collections.Generic.IEnumerable.GetEnumerator() at System.Linq.Enumerable.Count[TSource](IEnumerable`1 source) at ASP._Page_Views_Home_CustomersDetails_cshtml.Execute() in c:\Users\Administrator\Desktop\new app DEMO2\MvcApplication4 - LATEST -\MvcApplication4\Views\Home\CustomersDetails.cshtml:line 6 at System.Web.WebPages.WebPageBase.ExecutePageHierarchy() at System.Web.Mvc.WebViewPage.ExecutePageHierarchy() at System.Web.WebPages.StartPage.RunPage() at System.Web.WebPages.StartPage.ExecutePageHierarchy() at System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) at System.Web.Mvc.RazorView.RenderView(ViewContext viewContext, TextWriter writer, Object instance) at System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext, TextWriter writer) at System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) at System.Web.Mvc.ControllerActionInvoker.InvokeActionResult(ControllerContext controllerContext, ActionResult actionResult) at System.Web.Mvc.ControllerActionInvoker.c__DisplayClass1c.b__19() at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func`1 continuation) InnerException: System.Data.SqlClient.SqlException HResult=-2146232060 Message=Some part of your SQL statement is nested too deeply. Rewrite the query or break it up into smaller queries. Source=.Net SqlClient Data Provider ErrorCode=-2146232060 Class=15 LineNumber=105 Number=191 Procedure="" StackTrace: at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction) at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction) at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady) at System.Data.SqlClient.SqlDataReader.TryConsumeMetaData() at System.Data.SqlClient.SqlDataReader.get_MetaData() at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString) at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource`1 completion, Int32 timeout, Task& task, Boolean asyncWrite) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method) at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method) at System.Data.SqlClient.SqlCommand.ExecuteDbDataReader(CommandBehavior behavior) at System.Data.Common.DbCommand.ExecuteReader(CommandBehavior behavior) at System.Data.EntityClient.EntityCommandDefinition.ExecuteStoreCommands(EntityCommand entityCommand, CommandBehavior behavior) InnerException: 

那么是什么导致了这个错误？

更新：-

Answer 1

LINQ，对于其大多数命令，使用延迟执行。 它会一直等到您将查询发送到该数据库之前实际调用数据。 在这里看起来所有这些查询都被推迟到稍后，当你尝试从contactInfos中获取某些内容时。

我会尝试让它执行，就像在某处抛出.ToList（）一样，尝试减少SQL中的嵌套。

编辑：因为，根据评论，你似乎在第一个查询得到错误，你能不能试着说它where id.Contains(accountsitemapping.ACCOUNTID) ？

Answer 2

为了将来参考，您可以使用以下命令记录生成的SQL：

 var db = new DbContext(); db.Database.Log = Console.Write; 

这将允许您找出哪些部分正在深层嵌套。 从那里，您可能必须重新编写查询以在第二步中加载昂贵的计算。 或者考虑将其编写为存储过程。