EntityFramework:无效的列名*_ID1

Question

我正在尝试为几个名为' Employee'和' 的表实现DbContext.Department员工和部门之间的关系是多对一的.即部门可以有很多员工.

下面是我设计的EntityFramework类(CodeFirst方法)

    [Table("Employee")]
    public class Employee
    {
        [DatabaseGenerated(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.Identity)]
        public int Id { get; set; }

        [Column("Name")]
        public string Name { get; set; }

        [Column("Department_ID")]        
        public int Department_ID { get; set; }

        public virtual Department Department { get; set; }
    }

[Table("Department")]
    public class Department
    {
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int ID { get; set; }

        [Column("Name")]        
        public string Name { get; set; }

        public virtual ICollection<Employee>  Employees { get; set; }
    }

在添加员工记录时,我得到的是异常

"Invalid column name 'Department_ID1'." 

我不确定为什么EF指的是Department_ID1.我需要在OnModelCreating方法中添加配置DbContext吗？

我正在使用EF版本 6.1.1

Answer 1

喜花了一些时间,我可以通过解决这个问题ForeignKey的属性public virtual Department Department { get; set; }的财产Employee类.

请看下面的代码.

 [Table("Employee")]
public class Employee
{
    [DatabaseGenerated(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.Identity)]
    public int Id { get; set; }

    [Column("Name")]
    public string Name { get; set; }

    [Column("Department_ID")]        
    public int Department_ID { get; set; }

    [ForeignKey("Department_ID")]
    public virtual Department Department { get; set; }
}

这解决了我的问题.有没有其他解决方案来解决这个问题？使用流畅的API？

Answer 2

我在EF one-many交易中也遇到了这个问题，该交易one具有List的many属性，而我的映射未指定该属性。例如：

public class Notification
{
    public long ID { get; set; }     

    public IList<NotificationRecipient> Recipients { get; set; }
}

然后

public class NotificationRecipient
{
    public long ID { get; set; }

    public long NotificationID { get; set; }

    public Notification Notification { get; set; }
}

然后在我的映射中，导致Exception（错误方式）的方式：

builder.HasOne(x => x.Notification).WithMany()
    .HasForeignKey(x => x.NotificationID);

解决该问题的方法（正确的方法）是指定WithMany属性：

builder.HasOne(x => x.Notification).WithMany(x => x.Recipients)
    .HasForeignKey(x => x.NotificationID);