将我的实体框架更新为6.0.0-alpha1后,我无法更新数据库.
这是我得到的错误：
这是我得到的错误：
PM> update-database -verbose Using StartUp project 'DataCenter'. Using NuGet project 'DataCenter.Domain'. Specify the '-Verbose' flag to view the sql statements being applied to the target database. Target database is: 'datacenter' (DataSource: .,Provider: System.Data.sqlClient,Origin: Configuration). Upgrading history table. ALTER TABLE [dbo].[__MigrationHistory] ADD [ContextKey] [nvarchar](512) NOT NULL DEFAULT 'DataCenter.Domain.Migrations.Configuration' ALTER TABLE [dbo].[__MigrationHistory] DROP CONSTRAINT [PK_dbo.__MigrationHistory] System.Data.sqlClient.sqlException (0x80131904): 'PK_dbo.__MigrationHistory' is not a constraint. Could not drop constraint. See prevIoUs errors. at System.Data.sqlClient.sqlConnection.OnError(sqlException exception,Boolean breakConnection,Action`1 wrapCloseInAction) at System.Data.sqlClient.sqlInternalConnection.OnError(sqlException exception,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.sqlCommand.RunExecuteNonQueryTds(String methodName,Boolean async,Int32 timeout) at System.Data.sqlClient.sqlCommand.InternalExecuteNonQuery(TaskCompletionSource`1 completion,String methodName,Boolean sendToPipe,Int32 timeout,Boolean asyncWrite) at System.Data.sqlClient.sqlCommand.ExecuteNonQuery() at System.Data.Entity.Migrations.DbMigrator.Executesql(DbTransaction transaction,MigrationStatement migrationStatement) at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.Executesql(DbTransaction transaction,MigrationStatement migrationStatement) at System.Data.Entity.Migrations.DbMigrator.ExecuteStatements(IEnumerable`1 migrationStatements) at System.Data.Entity.Migrations.Infrastructure.MigratorBase.ExecuteStatements(IEnumerable`1 migrationStatements) at System.Data.Entity.Migrations.DbMigrator.UpgradeHistory(IEnumerable`1 upgradeOperations) at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.UpgradeHistory(IEnumerable`1 upgradeOperations) 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.RunCore() at System.Data.Entity.Migrations.Design.ToolingFacade.BaseRunner.Run() ClientConnectionId:eda1a366-d3c8-44de-8cc9-8f64e2511b4e 'PK_dbo.__MigrationHistory' is not a constraint. Could not drop constraint. See prevIoUs errors.@H_301_4@这是什么原因？我查询了“PK_dbo .__ MigrationHistory”的sysobjects表,但不存在.
任何想法？提前致谢.
解决方法
好.我找到了解决方案.
看来,EF希望__MigrationHistory表的主键约束具有名称PK_dbo .__MigrationHistory.但它是PK___MigrationHistory.
看来,EF希望__MigrationHistory表的主键约束具有名称PK_dbo .__MigrationHistory.但它是PK___MigrationHistory.
所以下面的sql语句将会做到这一点.
ALTER TABLE __MigrationHistory drop CONSTRAINT PK___MigrationHistory ALTER TABLE __MigrationHistory ADD CONSTRAINT [PK_dbo.__MigrationHistory] PRIMARY KEY (MigrationId)@H_301_4@之后我已经使用update-database没有错误.
