找不到对象“dbo.course”，因为它不存在或您没有权限

Question

我正在开发一个 ASP.NET MVC5 Web 应用程序。我正在使用 Entity Framework 6 来满足我的数据存储需求。我在启用迁移的情况下使用它的代码优先功能。自动迁移设置为 false。

我有两张表要更改。第一个表称为课程，这是它的模型。

public class course
{
    [Key]
    public int courseID { get; set; }
    public int categoryID { get; set; }
    public int PaymentOptionsID { get; set; }
    [Required]
    [DisplayName("Course Code")]
    public string courseCode { get; set; }
    [Required]
    [DisplayName("Course Name")]
    public string courseName { get; set; }
    [Required]
    [DataType(DataType.Currency)]
    public decimal price { get; set; }
    [DataType(DataType.MultilineText)]
    [DisplayName("Course Description")]
    [StringLength(255, ErrorMessage = "Only a maximum of 255 characters are                                     allowed")]
    public string courseDescription { get; set; }
    [Required]
    [DisplayName("Study Material")]
    public string courseIncludes { get; set; }
    public string courseInfoUrl { get; set; }

    public virtual ICollection<enrollment> enrollment { get; set; }
    public virtual courseCategory courseCategory { get; set; }
    public virtual PaymentOptions PaymentOptions { get; set; }
}

第二个表的名称是 paymentOptions，这是它​​的模型。

public class PaymentOptions
{
    [Key]
    public int PaymentOptionsID { get; set; }
    public int courseID { get; set; }
    [DisplayName("Payment Options")]
    public string paymentOption {get; set; }
}

我添加了 5 个迁移，它们运行良好。现在我正在尝试添加第六个，我正在尝试对表格进行以下更改

public class course
{
    [Key]
    public int courseID { get; set; }
    public int categoryID { get; set; }
    public int PaymentOptionsID { get; set; }
    [Required]
    [DisplayName("Course Code")]
    public string courseCode { get; set; }
    [Required]
    [DisplayName("Course Name")]
    public string courseName { get; set; }
    [Required]
    [DataType(DataType.Currency)]
    public decimal price { get; set; }
    [Required]
    [DisplayName("Course Includes")]
    public string courseIncludes { get; set; }
    public string courseInfoUrl { get; set; }

    public virtual ICollection<enrollment> enrollment { get; set; }
    public virtual courseCategory courseCategory { get; set; }
    public virtual ICollection<PaymentOptions> PaymentOptions { get; set; }
}    

public class PaymentOptions
{
    [Key]
    public int PaymentOptionsID { get; set; }
    public int courseID { get; set; }
    [DisplayName("Payment Options")]
    public string paymentOption {get; set; }

    public virtual ICollection<course> course { get; set; }
}

当我添加迁移时它工作正常，但是当我突然点击 update-database 命令时，我得到了这个错误

“找不到对象“dbo.course”，因为它不存在或者您没有权限。”

这就是迁移的样子。

public partial class AddPaymentOptionsagain : DbMigration
{
    public override void Up()
    {
        RenameTable(name: "dbo.course", newName: "PaymentOptionscourse");
        DropForeignKey("dbo.course", "PaymentOptions_PaymentOptionsID", "dbo.PaymentOptions");
        DropIndex("dbo.course", new[] { "PaymentOptions_PaymentOptionsID" });
        AddColumn("dbo.course", "PaymentOptionsID", c => c.Int(nullable: false));
        CreateIndex("dbo.PaymentOptionscourse", "PaymentOptions_PaymentOptionsID");
        CreateIndex("dbo.PaymentOptionscourse", "course_courseID");
        AddForeignKey("dbo.PaymentOptionscourse", "PaymentOptions_PaymentOptionsID", "dbo.PaymentOptions", "PaymentOptionsID", cascadeDelete: true);
        AddForeignKey("dbo.PaymentOptionscourse", "course_courseID", "dbo.course", "courseID", cascadeDelete: true);
        DropColumn("dbo.course", "courseDescription");
        DropColumn("dbo.course", "PaymentOptions_PaymentOptionsID");
    }

    public override void Down()
    {
        AddColumn("dbo.course", "PaymentOptions_PaymentOptionsID", c => c.Int());
        AddColumn("dbo.course", "courseDescription", c => c.String(maxLength: 255));
        DropForeignKey("dbo.PaymentOptionscourse", "course_courseID", "dbo.course");
        DropForeignKey("dbo.PaymentOptionscourse", "PaymentOptions_PaymentOptionsID", "dbo.PaymentOptions");
        DropIndex("dbo.PaymentOptionscourse", new[] { "course_courseID" });
        DropIndex("dbo.PaymentOptionscourse", new[] { "PaymentOptions_PaymentOptionsID" });
        DropColumn("dbo.course", "PaymentOptionsID");
        CreateIndex("dbo.course", "PaymentOptions_PaymentOptionsID");
        AddForeignKey("dbo.course", "PaymentOptions_PaymentOptionsID", "dbo.PaymentOptions", "PaymentOptionsID");
        RenameTable(name: "dbo.PaymentOptionscourse", newName: "course");
    }
}

我已阅读有关 stackoverflow、http://forums.asp.net、msdn.microsoft.com › SQL Server 的所有问题，但我似乎仍然无法弄清楚为什么会发生这种情况以及我需要做些什么来解决它。

任何帮助将不胜感激。在此先感谢

Answer 1

我在您的陈述顺序中看到了问题。您在重命名后尝试引用该对象。

 RenameTable(name: "dbo.course", newName: "PaymentOptionscourse");
    DropForeignKey("dbo.course", "PaymentOptions_PaymentOptionsID", "dbo.PaymentOptions");
    DropIndex("dbo.course", new[] { "PaymentOptions_PaymentOptionsID" });

试试这个

 RenameTable(name: "dbo.course", newName: "PaymentOptionscourse");
    DropForeignKey("dbo.PaymentOptionscourse", "PaymentOptions_PaymentOptionsID", "dbo.PaymentOptions");
    DropIndex("dbo.PaymentOptionscourse", new[] { "PaymentOptions_PaymentOptionsID" });
    AddColumn("dbo.PaymentOptionscourse", "PaymentOptionsID", c => c.Int(nullable: false));
    CreateIndex("dbo.PaymentOptionscourse", "PaymentOptions_PaymentOptionsID");
    CreateIndex("dbo.PaymentOptionscourse", "course_courseID");
    AddForeignKey("dbo.PaymentOptionscourse", "PaymentOptions_PaymentOptionsID", "dbo.PaymentOptions", "PaymentOptionsID", cascadeDelete: true);
    AddForeignKey("dbo.PaymentOptionscourse", "course_courseID", "dbo.PaymentOptionscourse", "courseID", cascadeDelete: true);
    DropColumn("dbo.PaymentOptionscourse", "courseDescription");
    DropColumn("dbo.PaymentOptionscourse", "PaymentOptions_PaymentOptionsID");