迁移后ASP.NET更新数据库错误26

大家好

我正在尝试在ASP.NET上使用SQL server进行迁移

下午1点，我输入了：

启用迁移-ContextTypeName StudentAca.Models.Student+AcademyContext

添加迁移初始值

上面的命令很有效，但在它们之后

更新数据库显示如下

System.Data.SqlClient.SqlException (0x80131904): A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)
   at System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, DbConnectionPool pool, String accessToken, Boolean applyTransientFaultHandling)
   at System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions)
   at System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnectionPool pool, DbConnection owningObject, DbConnectionOptions options, DbConnectionPoolKey poolKey, DbConnectionOptions userOptions)
   at System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
   at System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   at System.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   at System.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource`1 retry)
   at System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry)
   at System.Data.SqlClient.SqlConnection.Open()
   at System.Data.Entity.Infrastructure.Interception.DbConnectionDispatcher.<Open>b__36(DbConnection t, DbConnectionInterceptionContext c)
   at System.Data.Entity.Infrastructure.Interception.InternalDispatcher`1.Dispatch[TTarget,TInterceptionContext](TTarget target, Action`2 operation, TInterceptionContext interceptionContext, Action`3 executing, Action`3 executed)
   at System.Data.Entity.Infrastructure.Interception.DbConnectionDispatcher.Open(DbConnection connection, DbInterceptionContext interceptionContext)
   at System.Data.Entity.SqlServer.SqlProviderServices.<>c__DisplayClass33.<UsingConnection>b__32()
   at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.<>c__DisplayClass1.<Execute>b__0()
   at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult](Func`1 operation)
   at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute(Action operation)
   at System.Data.Entity.SqlServer.SqlProviderServices.UsingConnection(DbConnection sqlConnection, Action`1 act)
   at System.Data.Entity.SqlServer.SqlProviderServices.UsingMasterConnection(DbConnection sqlConnection, Action`1 act)
   at System.Data.Entity.SqlServer.SqlProviderServices.CreateDatabaseFromScript(Nullable`1 commandTimeout, DbConnection sqlConnection, String createDatabaseScript)
   at System.Data.Entity.SqlServer.SqlProviderServices.DbCreateDatabase(DbConnection connection, Nullable`1 commandTimeout, StoreItemCollection storeItemCollection)
   at System.Data.Entity.Core.Common.DbProviderServices.CreateDatabase(DbConnection connection, Nullable`1 commandTimeout, StoreItemCollection storeItemCollection)
   at System.Data.Entity.Core.Objects.ObjectContext.CreateDatabase()
   at System.Data.Entity.Migrations.Utilities.DatabaseCreator.Create(DbConnection connection)
   at System.Data.Entity.Migrations.DbMigrator.EnsureDatabaseExists(Action mustSucceedToKeepDatabase)
   at System.Data.Entity.Migrations.Infrastructure.MigratorBase.EnsureDatabaseExists(Action mustSucceedToKeepDatabase)
   at System.Data.Entity.Migrations.DbMigrator.Update(String targetMigration)
   at System.Data.Entity.Migrations.Infrastructure.MigratorBase.Update(String targetMigration)
   at System.Data.Entity.Migrations.Design.ToolingFacade.UpdateRunner.Run()
   at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate)
   at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate)
   at System.Data.Entity.Migrations.Design.ToolingFacade.Run(BaseRunner runner)
   at System.Data.Entity.Migrations.Design.ToolingFacade.Update(String targetMigration, Boolean force)
   at System.Data.Entity.Migrations.UpdateDatabaseCommand.<>c__DisplayClass2.<.ctor>b__0()
   at System.Data.Entity.Migrations.MigrationsDomainCommand.Execute(Action command)
ClientConnectionId:00000000-0000-0000-0000-000000000000
Error Number:-1,State:0,Class:20
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)

System.Data.SqlClient.SqlException（0x80131904）：建立到SQL Server的连接时发生与网络相关或特定于实例的错误。找不到服务器或无法访问服务器。验证实例名称是否正确，以及SQL Server是否配置为允许远程连接。（提供程序：SQL网络接口，错误：26-定位指定的服务器/实例时出错）
位于System.Data.SqlClient.SqlInternalConnectionDS..ctor（DbConnectionPoolIdentity、SqlConnectionString connectionOptions、SqlCredential凭证、对象提供信息、String newPassword、SecureString newSecurePassword、Boolean redirectedUserInstance、SqlConnectionString userConnectionOptions、SessionData重新连接SessionData、DbConnectionPool池、String accessToken、Boolean applyTransientF奥兰多（荷兰）
位于System.Data.SqlClient.SqlConnectionFactory.CreateConnection（DbConnectionOptions、DbConnectionPoolKey、Object poolGroupProviderInfo、DbConnectionPool、DBConnectionOwningConnection、DbConnectionOptions用户选项）
位于System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection（DbConnectionPool池、DbConnectionOwningObject、DbConnectionOptions选项、DbConnectionPoolKey池键、DbConnectionOptions用户选项）
位于System.Data.ProviderBase.DbConnectionPool.CreateObject（DbConnection-owningObject、DbConnectionOptions-userOptions、DbConnectionInternal-oldConnection）
位于System.Data.ProviderBase.DbConnectionPool.UserCreateRequest（DbConnection owningObject、DbConnectionOptions userOptions、DbConnectionInternal oldConnection）
位于System.Data.ProviderBase.DbConnectionPool.TryGetConnection（DbConnection owningObject、UInt32 waitForMultipleObjectsTimeout、Boolean allowCreate、Boolean OnlyOnEckConnection、DbConnectionOptions userOptions、DbConnectionInternal和connection）
位于System.Data.ProviderBase.DbConnectionPool.TryGetConnection（DbConnection owningObject、TaskCompletionSource`1重试、DbConnectionOptions用户选项、DbConnectionInternal和connection）
位于System.Data.ProviderBase.DbConnectionFactory.TryGetConnection（DbConnection owningConnection、TaskCompletionSource`1重试、DbConnectionOptions用户选项、DbConnectionInternal oldConnection、DbConnectionInternal&connection）
位于System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal（DbConnection outerConnection、DbConnectionFactory connectionFactory、TaskCompletionSource`1重试，DbConnectionOptions用户选项）
位于System.Data.ProviderBase.DbConnectionClosed.TryOpenConnection（DbConnection outerConnection、DbConnectionFactory connectionFactory、TaskCompletionSource`1重试、DbConnectionOptions用户选项）
位于System.Data.SqlClient.SqlConnection.TryOpenInner（TaskCompletionSource`1重试）
位于System.Data.SqlClient.SqlConnection.TryOpen（TaskCompletionSource`1重试）
在System.Data.SqlClient.SqlConnection.Open（）处
在System.Data.Entity.Infrastructure.Interception.DbConnectionDispatcher.b_u36（DbConnection t，DbConnectionInterceptionContext c）
在System.Data.Entity.Infrastructure.InternalDispatcher`1.Dispatch[TTarget，TInterceptionContext]（TTarget，Action`2 operation，TInterceptionContext interceptionContext，Action`3 executing，Action`3 executed）
位于System.Data.Entity.Infrastructure.Interception.DbConnectionDispatcher.Open（DbConnection连接，DbInterceptionContext interceptionContext）
位于System.Data.Entity.SqlServer.SqlProviderServices.c__DisplayClass33.b__u32（）
在System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.c__DisplayClass1.b__0（）中
在System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult]（Func`1操作）中
位于System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute（操作操作）
位于System.Data.Entity.SqlServer.SqlProviderServices.UsingConnection（DbConnection-sqlConnection，Action`1-act）
位于System.Data.Entity.SqlServer.SqlProviderServices.UsingMasterConnection（DbConnection-sqlConnection，Action`1-act）
位于System.Data.Entity.SqlServer.SqlProviderServices.CreateDatabaseFromScript（可为null的`1 commandTimeout、DbConnection sqlConnection、String createDatabaseScript）
位于System.Data.Entity.SqlServer.SqlProviderServices.DbCreateDatabase（DbConnection连接，Nullable`1 commandTimeout，StoreItemCollection StoreItemCollection）
位于System.Data.Entity.Core.Common.DbProviderServices.CreateDatabase（DbConnection连接，Nullable`1 commandTimeout，StoreItemCollection StoreItemCollection）
位于System.Data.Entity.Core.Objects.ObjectContext.CreateDatabase（）处
位于System.Data.Entity.Migrations.Utilities.DatabaseCreator.Create（数据库连接）
位于System.Data.Entity.Migrations.Dbmigator.EnsureDatabaseExists（操作必须成功才能访问数据库）
位于System.Data.Entity.Migrations.Infrastructure.MigratorBase.EnsureDatabaseExists（操作必须成功才能使用数据库）
位于System.Data.Entity.Migrations.DbMigrator.Update（字符串targetMigration）
位于System.Data.Entity.Migrations.Infrastructure.MigratorBase.Update（字符串targetMigration）
在System.Data.Entity.Migrations.Design.ToolingFacade.UpdateRunner.Run（）中
在System.AppDomain.DoCallBack（CrossAppDomainDelegate callBackDelegate）处
在System.AppDomain.DoCallBack（CrossAppDomainDelegate callBackDelegate）处
位于System.Data.Entity.Migrations.Design.ToolingFacade.Run（BaseRunner）
位于System.Data.Entity.Migrations.Design.ToolingFacade.Update（字符串targetMigration，布尔力）
在System.Data.Entity.Migrations.UpdateDatabaseCommand.c__DisplayClass2.b__0（）中
位于System.Data.Entity.Migrations.MigrationsDomainCommand.Execute（操作命令）
客户端连接ID:00000000-0000
<connectionStrings>
    <add name="DefaultConnection" connectionString="Data Source=(LocalDb)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\aspnet-StudentAca-20170614031539.mdf;Initial Catalog=aspnet-StudentAca-20170614031539;Integrated Security=True" providerName="System.Data.SqlClient" />
    <add name="AcademyContext" connectionString="Data Source=(LocalDb)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\students.mdf;Initial Catalog=studentManager;Integrated Security=True;MultipleActiveResultSets=True" providerName="System.Data.SqlClient" />
  </connectionStrings>