EF 6桥接表插入不起作用

Question

我仍在尝试学习如何使用EF并遇到桥接表的问题。

当我尝试创建一个关联Order的新Resources时，我收到以下SQL错误：

{"Violation of PRIMARY KEY constraint 'PK_Resource_Type'. Cannot insert duplicate key in object 'dbo.Resource_Type'. The duplicate key value is (2).\r\nThe statement has been terminated."}

代码看起来像这样

ResourceType resource = new ResourceType();
resource.ID = 2;
resource.Name = "Van"
order.resourceType().Add(resource)

db.Orders.Add(order);
db.SaveChanges();

表格如下所示

--Order table

CREATE TABLE [dbo].[Orders](
[Order_ID] [int] IDENTITY(1,1) NOT NULL,
[OrdernName] [varchar](100) NOT NULL,

CONSTRAINT [PK_Orders] PRIMARY KEY CLUSTERED
(
    [Order_ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO


--Resource Type table

CREATE TABLE [dbo].[Resource_Type](
[ResourceType_ID] [int] NOT NULL,
[ResourceType] [varchar] (30) NOT NULL

CONSTRAINT [PK_Resource_Type] PRIMARY KEY CLUSTERED
(
   [ResourceType_ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO


--Resource Type To Order table

CREATE TABLE [dbo].[Resource_Type_Order](
[ResourceType_ID] [int] NOT NULL,
[Order_ID] [int] NOT NULL


CONSTRAINT [PK_Resource_Type_Order] PRIMARY KEY CLUSTERED
(
   [ResourceType_ID] ASC,
   [Order_ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO


ALTER TABLE [dbo].[Resource_Type_Order] WITH CHECK ADD CONSTRAINT FK_Order_Resource_Type_Order FOREIGN KEY([Order_ID])
REFERENCES [dbo].[Orders]([Order_ID])
GO


ALTER TABLE [dbo].[Resource_Type_Order] WITH CHECK ADD CONSTRAINT FK_Resource_Type_Order_Resource_Type FOREIGN KEY([ReosurceType_ID])
REFERENCES [dbo].[Resource_Type]([Resource_ID])
GO

我是否正确使用桥接表？在我添加一个带有两个资源（汽车ID = 1和van ID = 2）的订单（ID = 1）后，我希望我的桥表看起来像这样。