相关疑难解决方法(0)

我已经和它搏斗了一段时间,并且无法弄清楚发生了什么.我有一个卡片实体,其中包含Sides(通常为2个) - 卡片和侧面都有一个舞台.我正在使用EF Codefirst迁移,并且迁移失败并出现此错误:

在表'Sides'上引入FOREIGN KEY约束'FK_dbo.Sides_dbo.Cards_CardId'可能会导致循环或多个级联路径.指定ON DELETE NO ACTION或ON UPDATE NO ACTION,或修改其他FOREIGN KEY约束.

这是我的卡片实体:

public class Card
{
    public Card()
    {
        Sides = new Collection<Side>();
        Stage = Stage.ONE;
    }

    [Key]
    [Required]
    public virtual int CardId { get; set; }

    [Required]
    public virtual Stage Stage { get; set; }

    [Required]
    [ForeignKey("CardId")]
    public virtual ICollection<Side> Sides { get; set; }
}

这是我的Side实体:

public class Side
{
    public Side()
    {
        Stage = Stage.ONE;
    }

    [Key]
    [Required]     
    public virtual int …

我正在运行efcore 2.0.1.

我有一个模特:

public class BigAwesomeDinosaurWithTeeth
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public Guid Id { get; set; }

    public ICollection<YummyPunyPrey> YummyPunyPrey { get; set; }
}
public class YummyPunyPrey
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public Guid Id { get; set; }
    public Guid? BigAwesomeDinosaurWithTeethId { get; set; }

    [ForeignKey("BigAwesomeDinosaurWithTeethId")]
    public BigAwesomeDinosaurWithTeeth BigAwesomeDinosaurWithTeeth { get; set; }

}

我对这两个课程没有流利的api.但是当我生成迁移时

constraints: table =>
            {
                table.PrimaryKey("PK_YummyPunyPrey", x => x.Id);
                table.ForeignKey(
                    name: "FK_YummyPunyPrey_BigAwesomeDinosaurWithTeeth_BigAwesomeDinosaurWithTeethId",
                    column: x => x.BigAwesomeDinosaurWithTeethId,
                    principalTable: "BigAwesomeDinosaurWithTeeth",
                    principalColumn: "Id",
                    onDelete: ReferentialAction.Restrict);
            });

为什么它生成onDelete:ReferentialAction.Restrict当文档说它应该作为ClientSetNull …