错误：每个表中的列名必须是唯一的

Question

执行update-database时出现错误：“每个表中的列名必须是唯一的。”表'dbo.OrderForms'中的列名'OrderRecieveDate'被指定不止一次。”我已经尝试了所有我能想到的方法来修复它，但到目前为止还没有任何结果。之前，我可以通过我创建的网站添加/更新/删除表格中的行，但现在该功能看起来并不奏效。我甚至无法让数据库在此时添加我的种子数据。

我的上下文/型号文件：

public class OrderFormContext : DbContext 
{ 
    public DbSet<OrderForm> OrderForms { get; set; } 
} 

public class OrderForm 
{ 
    [Key, Display(Name= "Order ID")] 
    [ScaffoldColumn(false)] 
    public int OrderID { get; set; } 


    private DateTime _date = DateTime.Today; 
    [Display(Name = "Date Posted")] 
    [ScaffoldColumn(false)] 
    public DateTime OrderPostDate 
    { 
     get { return _date; } 
     set { _date = value; } 
    } 

    [EnumDataType(typeof(PersonReqID)),Display(Name = "Person Requesting")] 
    public PersonReqID PersonReq { get; set; } 

    [StringLength(100), Display(Name = "Grant")] 
    public string GrantID { get; set; } 

    [StringLength(10000), Display(Name = "Product Description"), DataType(DataType.MultilineText)] 
    public string ItemDescription { get; set; } 

    [StringLength(100), Display(Name = "Quantity")] 
    public string ItemQuantity { get; set; } 

    [StringLength(100), Display(Name = "Price")] 
    public string UnitPrice { get; set; } 

    [StringLength(100), Display(Name = "Company")] 
    public string CompanyID { get; set; } 

    [StringLength(100), Display(Name = "Catalog #")] 
    public string CatalogNum { get; set; } 

    [ScaffoldColumn(false)] 
    [Range(typeof(DateTime), "1/1/1111", "1/1/3000", ErrorMessage = "Please provide a date.")] 
    [DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:d}")] 
    public DateTime OrderMadeDate { get; set; } 

    [ScaffoldColumn(false)] 
    [Range(typeof(DateTime), "1/1/1111", "1/1/3000", ErrorMessage = "Please provide a date.")] 
    [DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:d}")] 
    public DateTime OrderRecieveDate { get; set; } 

    [ScaffoldColumn(false)] 
    [EnumDataType(typeof(PersonRecID)), Display(Name = "Person Recieving")] 
    public PersonRecID PersonRec { get; set; } 

    [ScaffoldColumn(false)] 
    [StringLength(100), Display(Name = "Item Location")] 
    public string ItemLoc { get; set; } 
} 

我Configuration.cs文件：

context.OrderForms.AddOrUpdate(
       new OrderForm 
       { 
        OrderID=1, 
        OrderPostDate=DateTime.Now, 
        PersonReq=PersonReqID.Jake, 
        GrantID="NASA", 
        ItemDescription="Grenades", 
        ItemQuantity="100", 
        UnitPrice="1.50", 
        CompanyID="Grenades UNLMTD", 
        CatalogNum="G1001", 
        PersonRec=PersonRecID.Ajit, 
        ItemLoc="Freezer" 
       } 

       ); 

     context.SaveChanges(); 

最后我xxxxxxx_initial.cs迁移文件：

public override void Up() 
    { 
     AddColumn("dbo.OrderForms", "OrderRecieveDate", c => 
     c.DateTime(nullable: false, defaultValue: new DateTime(1000, 1, 1))); 
     AddColumn("dbo.OrderForms", "OrderMadeDate", d => 
     d.DateTime(nullable: false, defaultValue: new DateTime(1000, 1, 1))); 

    } 

    public override void Down() 
    { 
     DropColumn("dbo.OrderForms", "OrderRecieveDate"); 
     DropColumn("dbo.OrderForms", "OrderMadeDate"); 

    } 

我很新的网页设计，所以我只是总结一切，我认为可能会导致一个问题。这是我的OrderForms.dbo文件的表定义。

CREATE TABLE [dbo].[OrderForms] (
[OrderID]   INT   IDENTITY (1, 1) NOT NULL, 
[GrantID]   NVARCHAR (100) NULL, 
[ItemDescription] NVARCHAR (MAX) NULL, 
[ItemQuantity]  NVARCHAR (100) NULL, 
[UnitPrice]  NVARCHAR (100) NULL, 
[CompanyID]  NVARCHAR (100) NULL, 
[CatalogNum]  NVARCHAR (100) NULL, 
[OrderDate]  NVARCHAR (100) NULL, 
[ItemLoc]   NVARCHAR (100) NULL, 
[PersonReq]  INT   DEFAULT ((0)) NULL, 
[PersonRec]  INT   DEFAULT ((0)) NULL, 
[OrderPostDate] DATETIME  DEFAULT ('1900-01-01T00:00:00.000') NULL, 
[OrderRecieveDate] DATETIME  DEFAULT ('2013-01-01T00:00:00.000') NULL, 
[OrderMadeDate] DATETIME  DEFAULT ('2013-01-01T00:00:00.000') NULL, 
CONSTRAINT [PK_dbo.OrderForms] PRIMARY KEY CLUSTERED ([OrderID] ASC) 

）;

任何帮助将不胜感激。我似乎无法弄清楚该列是如何创建两次的。我尝试删除数据库和先前的迁移，并执行'enable-migrations -forced'并从那里重新启动无效。这可能与我从最后缺乏EF背景知识有关。预先感谢任何帮助！

Answer 1

所以我可能会误解你有什么，但不要你在定义创建列一次：

CREATE TABLE [dbo].[OrderForms] (
[OrderID]   INT   IDENTITY (1, 1) NOT NULL, 
[GrantID]   NVARCHAR (100) NULL, 
[ItemDescription] NVARCHAR (MAX) NULL, 
[ItemQuantity]  NVARCHAR (100) NULL, 
[UnitPrice]  NVARCHAR (100) NULL, 
[CompanyID]  NVARCHAR (100) NULL, 
[CatalogNum]  NVARCHAR (100) NULL, 
[OrderDate]  NVARCHAR (100) NULL, 
[ItemLoc]   NVARCHAR (100) NULL, 
[PersonReq]  INT   DEFAULT ((0)) NULL, 
[PersonRec]  INT   DEFAULT ((0)) NULL, 
[OrderPostDate] DATETIME  DEFAULT ('1900-01-01T00:00:00.000') NULL, 
[OrderRecieveDate] DATETIME  DEFAULT ('2013-01-01T00:00:00.000') NULL, 
[OrderMadeDate] DATETIME  DEFAULT ('2013-01-01T00:00:00.000') NULL, 
CONSTRAINT [PK_dbo.OrderForms] PRIMARY KEY CLUSTERED ([OrderID] ASC) 

然后尝试再次创建它们

public override void Up() 
    { 
     AddColumn("dbo.OrderForms", "OrderRecieveDate", c => 
     c.DateTime(nullable: false, defaultValue: new DateTime(1000, 1, 1))); 
     AddColumn("dbo.OrderForms", "OrderMadeDate", d => 
     d.DateTime(nullable: false, defaultValue: new DateTime(1000, 1, 1))); 

    } 

如果你需要一些故障排除建议您可以使用sys.tables和sys.columns查找值，并在添加列上使用IF NOT EXISTS。

这将需要一些修改，但它可能足以让你去。

string columnToAdd = " ADD [" + columnList[i] + "] " + columnDataTypeList[i]; 
    string alterTableSQL = @"ALTER TABLE " + DestinationTbl + columnList[i]; 
    string columnMakerSQL += @"IF NOT EXISTS (SELECT * FROM sys.columns WHERE object_id = OBJECT_ID(N'" + DestinationTbl 
           + @"') AND name = '" + columnList[i] 
           + @"') BEGIN " 
           + alterTableSQL 
           + @" END ";