更新条目时出错。有关详细信息，请参阅内部异常。 - Linq 到实体

Question

一直在环顾四周，我似乎无法弄清楚出了什么问题。

目前我正在尝试在玩家死亡时使用新的高分更新我的数据库。但无论我选择尝试保存什么，它都会向我抛出异常。

代码：

 HighScore hs = new HighScore();
            var id = from i in db.HighScores
                     orderby i.ID descending
                     select i;
            int newId = 0;

            if (id.Count() == 0)
            {
                newId = 1;
            }
            else
            {
                newId = id.First().ID + 1;
            }
        hs.ID = 6; //I just hardcoded in 6 to make sure i wasent because of the newId      //thing, and i have checked if theres already something on the sixths spot as well.
            hs.UserHighscore = 100;
            hs.HighscoreUsername = "test";
            hs.GameID = 1;
            db.HighScores.AddObject(hs);
            db.SaveChanges();

我已经检查了一遍又一遍，但我似乎无法弄清楚问题所在。

如有任何帮助，将不胜感激。

例外：

System.Data.UpdateException was unhandled
  Message=An error occurred while updating the entries. See the inner exception 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(SaveOptions options)
       at System.Data.Objects.ObjectContext.SaveChanges()
       at MatematikSpilMenu.SaveBunniesSceen.SaveHighscore() in MatematikSpilMenu\SaveBunniesSceen.cs:line 173
       at MatematikSpilMenu.SaveBunniesSceen.Update(GameTime gameTime, Boolean otherScreenIsActive, Boolean coveredByOtherScreens) in C:\Users\Etarnalazure-Alien\documents\visual studio 2010\Projects\MatematikSpilMenu\MatematikSpilMenu\MatematikSpilMenu\SaveBunniesSceen.cs:line 110
       at MatematikSpilMenu.ScreenManager.Update(GameTime gameTime) in MatematikSpilMenu\ScreenManager.cs:line 101
       at Microsoft.Xna.Framework.Game.Update(GameTime gameTime)
       at Microsoft.Xna.Framework.Game.Tick()
       at Microsoft.Xna.Framework.Game.HostIdle(Object sender, EventArgs e)
       at Microsoft.Xna.Framework.GameHost.OnIdle()
       at Microsoft.Xna.Framework.WindowsGameHost.RunOneFrame()
       at Microsoft.Xna.Framework.WindowsGameHost.ApplicationIdle(Object sender, EventArgs e)
       at System.Windows.Forms.Application.ThreadContext.System.Windows.Forms.UnsafeNativeMethods.IMsoComponent.FDoIdle(Int32 grfidlef)
       at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.Run(Form mainForm)
       at Microsoft.Xna.Framework.WindowsGameHost.Run()
       at Microsoft.Xna.Framework.Game.RunGame(Boolean useBlockingRun)
       at Microsoft.Xna.Framework.Game.Run()
       at MatematikSpilMenu.Program.Main() in MatematikSpilMenu\Game1.cs:line 120
  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, Dictionary`2 identifierValues)
            at System.Data.Mapping.Update.Internal.DynamicUpdateCommand.Execute(UpdateTranslator translator, EntityConnection connection, Dictionary`2 identifierValues, List`1 generatedValues)
            at System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter)
       InnerException: System.NotSupportedException
            Message=Server-generated keys and server-generated values are not supported by SQL Server Compact.
            Source=System.Data.SqlServerCe.Entity
            StackTrace:
                 at System.Data.SqlServerCe.SqlGen.DmlSqlGenerator.GenerateReturningSql(StringBuilder commandText, DbModificationCommandTree tree, ExpressionTranslator translator, DbExpression returning)
                 at System.Data.SqlServerCe.SqlGen.DmlSqlGenerator.GenerateInsertSql(DbInsertCommandTree tree, List`1& parameters, Boolean isLocalProvider)
                 at System.Data.SqlServerCe.SqlGen.SqlGenerator.GenerateSql(DbCommandTree tree, List`1& parameters, CommandType& commandType, Boolean isLocalProvider)
                 at System.Data.SqlServerCe.SqlCeProviderServices.CreateCommand(DbProviderManifest providerManifest, DbCommandTree commandTree)
                 at System.Data.SqlServerCe.SqlCeProviderServices.CreateDbCommandDefinition(DbProviderManifest providerManifest, DbCommandTree commandTree)
                 at System.Data.Common.DbProviderServices.CreateCommandDefinition(DbCommandTree commandTree)
                 at System.Data.Common.DbProviderServices.CreateCommand(DbCommandTree commandTree)
                 at System.Data.Mapping.Update.Internal.UpdateTranslator.CreateCommand(DbModificationCommandTree commandTree)
            InnerException: 

Answer 1

根据我的经验，这通常是由 db 错误触发的，在我的情况下，它是与失败并引发根异常的表相关联的触发器。但是，在您的情况下，您似乎在使用自动编号（身份）字段时错误地尝试手动定义 id。

Answer 2

在我看来，问题的根源在于您使用的 SQL 服务器：

不支持服务器生成的键和服务器生成的值 SQL Server Compact。

您是否尝试在 SQL Server Compact 版本上使用自动增量 ID？我记不太清了，但也许用那个 SQL 版本是不可能的。我建议你先检查一下。

Answer 3

找到了解决方案，似乎它的数据库在使用太多地方时可能会出错（这只是我的猜测）。无论哪种方式，创建一个新表然后向其中添加东西似乎都可以解决它（没有使用身份。）

Answer 4

在我的情况下，在打开表数据库后，auto_ink 列的主键问题就消失了。

Answer 5

服务器生成的密钥表现不佳所以去检查数据库可能是你的数据库初级密钥是自动生成的密钥所以去尝试手动插入数据