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我正在使用 ASP.NET MVC 3 并通过 MVC 音乐商店和其他来源学习。我能够创建一个数据库并让它运行，但奇怪的是它在它运行后大约 5 个小时就崩溃了，并且出现了以下错误和堆栈跟踪：

注意：每当我发布网站时，情况似乎也是如此。我必须手动删除数据库才能重新创建它，然后它才能工作。但是现在我还活着，我不能这样做，因为数据已经存储在那里，我不想重做。

File already exists. Try using a different database name. [ File name = C:\HostingSpaces\...\wwwroot\App_Data\Test.sdf ]

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.Data.SqlServerCe.SqlCeException: File already exists. Try using a different database name. [ File name = C:\HostingSpaces\mtnp55\pricexperience.com\wwwroot\App_Data\Test.sdf ]

Source Error: 

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace: 


[SqlCeException (0x80004005): File already exists. Try using a different database name. [ File name = C:\HostingSpaces\...\wwwroot\App_Data\Test.sdf ]]
   System.Data.SqlServerCe.SqlCeEngine.ProcessResults(IntPtr pError, Int32 hr) +72
   System.Data.SqlServerCe.SqlCeEngine.CreateDatabase() +658
   System.Data.SqlServerCe.SqlCeProviderServices.DbCreateDatabase(DbConnection connection, Nullable`1 timeOut, StoreItemCollection storeItemCollection) +194
   System.Data.Objects.ObjectContext.CreateDatabase() +84
   System.Data.Entity.Internal.DatabaseOperations.Create(ObjectContext objectContext) +8
   System.Data.Entity.Database.Create() +76
   System.Data.Entity.CreateDatabaseIfNotExists`1.InitializeDatabase(TContext context) +387
   System.Data.Entity.<>c__DisplayClass2`1.<SetInitializerInternal>b__0(DbContext c) +75
   System.Data.Entity.Internal.<>c__DisplayClass5.<PerformDatabaseInitialization>b__3() +19
   System.Data.Entity.Internal.InternalContext.PerformInitializationAction(Action action) +72
   System.Data.Entity.Internal.InternalContext.PerformDatabaseInitialization() +169
   System.Data.Entity.Internal.LazyInternalContext.<InitializeDatabase>b__4(InternalContext c) +7
   System.Data.Entity.Internal.RetryAction`1.PerformAction(TInput input) +118
   System.Data.Entity.Internal.LazyInternalContext.InitializeDatabaseAction(Action`1 action) +190
   System.Data.Entity.Internal.LazyInternalContext.InitializeDatabase() +73
   System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type entityType) +28
   System.Data.Entity.Internal.Linq.InternalSet`1.Initialize() +62
   System.Data.Entity.Internal.Linq.InternalSet`1.get_InternalContext() +15
   System.Data.Entity.Infrastructure.DbQuery`1.System.Linq.IQueryable.get_Provider() +37
   System.Linq.Queryable.Where(IQueryable`1 source, Expression`1 predicate) +63
   PriceXperience.Controllers.AppsController.ViewLeaderboards(Int32 gameId) in C:\Users\Public\Documents\Development\...\Controllers\AppsController.cs:42
   lambda_method(Closure , ControllerBase , Object[] ) +101
   System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) +17
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +208
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +27
   System.Web.Mvc.<>c__DisplayClass15.<InvokeActionMethodWithFilters>b__12() +55
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +263
   System.Web.Mvc.<>c__DisplayClass17.<InvokeActionMethodWithFilters>b__14() +19
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +191
   System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +343
   System.Web.Mvc.Controller.ExecuteCore() +116
   System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +97
   System.Web.Mvc.ControllerBase.System.Web.Mvc.IController.Execute(RequestContext requestContext) +10
   System.Web.Mvc.<>c__DisplayClassb.<BeginProcessRequest>b__5() +37
   System.Web.Mvc.Async.<>c__DisplayClass1.<MakeVoidDelegate>b__0() +21
   System.Web.Mvc.Async.<>c__DisplayClass8`1.<BeginSynchronous>b__7(IAsyncResult _) +12
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +62
   System.Web.Mvc.<>c__DisplayClasse.<EndProcessRequest>b__d() +50
   System.Web.Mvc.SecurityUtil.<GetCallInAppTrustThunk>b__0(Action f) +7
   System.Web.Mvc.SecurityUtil.ProcessInApplicationTrust(Action action) +22
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +60
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +8841105
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +184

我已经尝试了很多事情，但仍然无法弄清楚为什么会这样。我确实有一个数据库初始化。

 System.Data.Entity.Database.SetInitializer<MobileEntities>(new SampleData());

public class SampleData : CreateDatabaseIfNotExists<MobileEntities>

当我尝试访问数据库时运行的代码如下：

public ActionResult ViewLeaderboards(int gameId)
        {
            var leaderboards = from u in mobileDB.Scores
                               where u.GameId == gameId
                               select u;

            return View(leaderboards.OrderByDescending(u => u.Score).ToList());
        }
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2 回答 2

2

发布时，您需要确保从 Global.asax 中删除初始化程序。Initializer 仅用于填充测试数据，不应在生产期间使用。我还记得在某处读到将 Initializer 设置为 null 可能会起作用。

Database.SetInitializer<MyContext>(null);

或者只是在发布之前注释掉调用 SetInitializer 的行。在发布之前，我还将我的 Initializer 类从项目中排除。

于 2011-08-15T01:15:06.863 回答
1

Code First 上下文的默认策略是 CreateDatabaseIfNotExists 的一个实例。所以有必要包括

Database.SetInitializer<MyContext>(null);

这样就不会调用默认初始化程序，这可能会导致错误！此外，将泛型标记设置为 null 时必须包含泛型标记，否则编译器会出错。

于 2014-06-29T22:59:11.430 回答