我在我的应用程序中使用SQL Server Compact Edition(本地数据库).但是当我使用实体框架时,我一直遇到一个非常烦人的UpdateException.我的数据库只有两个小表,外键关系将它们连接在一起.所以我问是否有数据库的替代品？或者这是唯一的选择吗？
更新:
这是EDMX地图.
以下是System.Windows.Markup.XamlParseException was unhandled
Message=Cannot create instance of 'MainWindow' defined in assembly 'AssignmentOrganizer, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'. Exception has been thrown by the target of an invocation. Error in markup file 'AssignmentOrganizer;component/MainWindow.xaml' Line 1 Position 9.
Source=PresentationFramework
LineNumber=1
LinePosition=9
StackTrace:
at System.Windows.Markup.XamlParseException.ThrowException(String message, Exception innerException, Int32 lineNumber, Int32 linePosition, Uri baseUri, XamlObjectIds currentXamlObjectIds, XamlObjectIds contextXamlObjectIds, Type objectType)
at System.Windows.Markup.XamlParseException.ThrowException(ParserContext parserContext, Int32 lineNumber, Int32 linePosition, String message, Exception innerException)
at System.Windows.Markup.BamlRecordReader.ThrowExceptionWithLine(String message, Exception innerException)
at System.Windows.Markup.BamlRecordReader.CreateInstanceFromType(Type type, Int16 typeId, Boolean throwOnFail)
at System.Windows.Markup.BamlRecordReader.GetElementAndFlags(BamlElementStartRecord bamlElementStartRecord, Object& element, ReaderFlags& flags, Type& delayCreatedType, Int16& delayCreatedTypeId)
at System.Windows.Markup.BamlRecordReader.BaseReadElementStartRecord(BamlElementStartRecord bamlElementRecord)
at System.Windows.Markup.BamlRecordReader.ReadElementStartRecord(BamlElementStartRecord bamlElementRecord)
at System.Windows.Markup.BamlRecordReader.ReadRecord(BamlRecord bamlRecord)
at System.Windows.Markup.BamlRecordReader.Read(Boolean singleRecord)
at System.Windows.Markup.TreeBuilderBamlTranslator.ParseFragment()
at System.Windows.Markup.TreeBuilder.Parse()
at System.Windows.Markup.XamlReader.LoadBaml(Stream stream, ParserContext parserContext, Object parent, Boolean closeStream)
at System.Windows.Application.LoadBamlStreamWithSyncInfo(Stream stream, ParserContext pc)
at System.Windows.Application.LoadComponent(Uri resourceLocator, Boolean bSkipJournaledProperties)
at System.Windows.Application.DoStartup()
at System.Windows.Application.<.ctor>b__0(Object unused)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Boolean isSingleParameter)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler)
at System.Windows.Threading.Dispatcher.WrappedInvoke(Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler)
at System.Windows.Threading.DispatcherOperation.InvokeImpl()
at System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(Object state)
at System.Threading.ExecutionContext.runTryCode(Object userData)
at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Windows.Threading.DispatcherOperation.Invoke()
at System.Windows.Threading.Dispatcher.ProcessQueue()
at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Boolean isSingleParameter)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler)
at System.Windows.Threading.Dispatcher.WrappedInvoke(Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler)
at System.Windows.Threading.Dispatcher.InvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Boolean isSingleParameter)
at System.Windows.Threading.Dispatcher.Invoke(DispatcherPriority priority, Delegate method, Object arg)
at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
at System.Windows.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
at System.Windows.Threading.Dispatcher.Run()
at System.Windows.Application.RunDispatcher(Object ignore)
at System.Windows.Application.RunInternal(Window window)
at System.Windows.Application.Run(Window window)
at System.Windows.Application.Run()
at AssignmentOrganizer.App.Main() in C:\Users\Mohit\Documents\Visual Studio 2010\Projects\AssignmentOrganizer\AssignmentOrganizer\obj\x86\Debug\App.g.cs:line 0
at System.AppDomain._nExecuteAssembly(Assembly assembly, String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()
InnerException: System.Reflection.TargetInvocationException
Message=Exception has been thrown by the target of an invocation.
Source=mscorlib
StackTrace:
at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandle& ctor, Boolean& bNeedSecurityCheck)
at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean fillCache)
at System.RuntimeType.CreateInstanceImpl(Boolean publicOnly, Boolean skipVisibilityChecks, Boolean fillCache)
at System.Activator.CreateInstance(Type type, Boolean nonPublic)
at System.Windows.Markup.BamlRecordReader.CreateInstanceFromType(Type type, Int16 typeId, Boolean throwOnFail)
InnerException: System.Data.UpdateException
Message=An error occurred while updating the entries. See the InnerException for details.
Source=System.Data.Entity
StackTrace:
at System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter)
at System.Data.EntityClient.EntityAdapter.Update(IEntityStateManager entityCache)
at System.Data.Objects.ObjectContext.SaveChanges(Boolean acceptChangesDuringSave)
at System.Data.Objects.ObjectContext.SaveChanges()
at AssignmentOrganizer.App_Data.AssignmentRepository.CreateAssignment(Assignment assignmentToCreate) in C:\Users\Mohit\Documents\Visual Studio 2010\Projects\AssignmentOrganizer\AssignmentOrganizer\App_Data\AssignmentRepository.cs:line 20
at AssignmentOrganizer.MainWindow..ctor() in C:\Users\Mohit\Documents\Visual Studio 2010\Projects\AssignmentOrganizer\AssignmentOrganizer\MainWindow.xaml.cs:line 34
InnerException: System.Data.EntityCommandCompilationException
Message=An error occurred while preparing the command definition. See the inner exception for details.
Source=System.Data.Entity
StackTrace:
at System.Data.Mapping.Update.Internal.UpdateTranslator.CreateCommand(DbModificationCommandTree commandTree)
at System.Data.Mapping.Update.Internal.DynamicUpdateCommand.CreateCommand(UpdateTranslator translator, DictionarySystem.Data.Mapping.Update.Internal.UpdateTranslator.Update中System.Data.Mapping.Update.Internal.DynamicUpdateCommand.Execute(UpdateTranslator转换器,EntityConnection连接,Dictionary 2 identifierValues, List1 generatedValues)的异常堆栈跟踪:
2 identifierValues)(IEntityStateManager stateManager,IEntityAdapter adapter)InnerException:System.NotSupportedException Message = SQL Server Compact不支持服务器生成的密钥和服务器生成的值.Source = System.Data.SqlServerCe.Entity StackTrace:在System.Data.SqlServerCe.SqlGen.DmlSqlGenerator.GenerateReturningSql(StringBuilder commandText,DbModificationCommandTree树,ExpressionTranslator转换器,DbExpression返回)处于System.Data.SqlServerCe.SqlGen.DmlSqlGenerator.GenerateInsertSql(DbInsertCommandTree)1& parameters, Boolean isLocalProvider)
at System.Data.SqlServerCe.SqlGen.SqlGenerator.GenerateSql(DbCommandTree tree, List在System.Data的System.Data.SqlServerCe.SqlCeProviderServices.CreateDbCommandDefinition(DbProviderManifest providerManifest,DbCommandTree commandTree)上的System.Data.SqlServerCe.SqlCeProviderServices.CreateCommand(DbProviderManifest providerManifest,DbCommandTree commandTree)中的树,列表1和参数,CommandType&commandType,Boolean isLocalProvider) System.Data.Mapping.Update.Internal.UpdateTranslator.CreateCommand(DbModificationCommandTree commandTree)上的System.Data.Common.DbProviderServices.CreateCommand(DbCommandTree commandTree)中的.Common.DbProviderServices.CreateCommandDefinition(DbCommandTree commandTree)InnerException:
Jon*_*eet 10
总有其他选择.问题是他们是否比数据库更好.您可以用XML或您自己的文件格式等存储您的数据.然后您必须编写适当的查询,更新代码等.这可能没问题 - 但是如果没有更多信息我们就不能说.
但是,在考虑另一种解决方案之前,我会深究为什么你会看到异常.当您更改存储层时,您可能会遇到一些您并未真正预料到会对您造成同样伤害的行为 - 此时可能更难诊断.一旦你弄清楚为什么你现在的方法不起作用,你就会更好地了解它是否值得改变.
