我创建了一个新的Asp.Net Core WebApi项目并简单地添加了IdentityDbContext,然后我在 Nuget Package Console 中写了这些命令:
PM> Add-Migration Initial
To undo this action, use Remove-Migration.
PM> Update-Database
Applying migration '20180516150423_Initial'.
Failed executing DbCommand (2ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE TABLE [AspNetRoles] (
[Id] nvarchar(450) NOT NULL,
[ConcurrencyStamp] nvarchar(max) NULL,
[Name] nvarchar(256) NULL,
[NormalizedName] nvarchar(256) NULL,
CONSTRAINT [PK_AspNetRoles] PRIMARY KEY ([Id])
);
fail: Microsoft.EntityFrameworkCore.Database.Command[20102]
Failed executing DbCommand (2ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE TABLE [AspNetRoles] (
[Id] nvarchar(450) NOT NULL,
[ConcurrencyStamp] nvarchar(max) NULL,
[Name] nvarchar(256) NULL,
[NormalizedName] nvarchar(256) NULL,
CONSTRAINT [PK_AspNetRoles] PRIMARY KEY ([Id])
);
System.Data.SqlClient.SqlException (0x80131904): There is already an object named 'AspNetRoles' in the database.
at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, 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, Boolean asyncWrite)
at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource`1 completion, Boolean sendToPipe, Int32 timeout, Boolean asyncWrite, String methodName)
at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()
at Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommand.Execute(IRelationalConnection connection, DbCommandMethod executeMethod, IReadOnlyDictionary`2 parameterValues)
ClientConnectionId:049426b7-c12c-421f-9236-c0212a40c216
Error Number:2714,State:6,Class:16
System.Data.SqlClient.SqlException (0x80131904): There is already an object named 'AspNetRoles' in the database.
at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, 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, Boolean asyncWrite)
at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource`1 completion, Boolean sendToPipe, Int32 timeout, Boolean asyncWrite, String methodName)
at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()
at Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommand.Execute(IRelationalConnection connection, DbCommandMethod executeMethod, IReadOnlyDictionary`2 parameterValues)
at Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommand.ExecuteNonQuery(IRelationalConnection connection, IReadOnlyDictionary`2 parameterValues)
at Microsoft.EntityFrameworkCore.Migrations.MigrationCommand.ExecuteNonQuery(IRelationalConnection connection, IReadOnlyDictionary`2 parameterValues)
at Microsoft.EntityFrameworkCore.Migrations.Internal.MigrationCommandExecutor.ExecuteNonQuery(IEnumerable`1 migrationCommands, IRelationalConnection connection)
at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.Migrate(String targetMigration)
at Microsoft.EntityFrameworkCore.Design.Internal.MigrationsOperations.UpdateDatabase(String targetMigration, String contextType)
at Microsoft.EntityFrameworkCore.Design.OperationExecutor.UpdateDatabase.<>c__DisplayClass0_1.<.ctor>b__0()
at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)
ClientConnectionId:049426b7-c12c-421f-9236-c0212a40c216
Error Number:2714,State:6,Class:16
There is already an object named 'AspNetRoles' in the database.
PM>
Google云端硬盘项目:https://drive.google.com/open?id=16bYS7br2Ba7NcJYatPBDG2Q921o3MFcK
如果你试图建立这个项目,你会非常帮助我。
答案 0 :(得分:2)
数据库中已有一个名为'AspNetRoles'的对象
AspNetRoles
表已存在。
你可以尝试两件事:
drop database <your_db_name>
。现在Add-Migration <MigrationClassName>
命令可以正常工作。
答案 1 :(得分:0)
我遇到了以下相同的错误。然后我将其修复如下:
dotnet ef migrations list
dotnet ef migrations remove
dotnet ef migrations add [new_dbo_name]
5。最后,尝试根据迁移列表再次进行更新:
dotnet ef database update [First]
dotnet ef database update [Second]
...
dotnet ef database update [new_dbo_name]
希望对您有帮助。 ^^