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具有级联更新和删除的同一个表的多个外键

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我正在尝试为一个实体添加多个外键,这些实体将通过级联更新和删除连接到同一个其他表 .

所以我有 SeriesArgument 实体:

public class Series : Entity<int>
{
    public string Name { get; set; }
    public int IterationsId { get; set; }
    public int KId { get; set; }
    public int LambdaId { get; set; }
    public int GradientId { get; set; }
    public int ImproveId { get; set; }
    public int TrainingId { get; set; }
    public DateTime CreateDateTime { get; set; }
    public DateTime? ChangeDateTime { get; set; }
    public virtual Argument Iterations { get; set; }
    public virtual Argument K { get; set; }
    public virtual Argument Lambda { get; set; }
    public virtual Argument Gradient { get; set; }
    public virtual Argument Improve { get; set; }
    public virtual Argument Training { get; set; }
}

public class Argument : Entity<int>
{
    public Argument()
    {
        Values = new List<ArgumentValue>();
    }

    public int Min { get; set; }
    public int Max { get; set; }
    public int Step { get; set; }
    public ArgumentType ArgumentType { get; set; }
    public virtual ICollection<ArgumentValue> Values { get; set; }
}

他们的映射:

public class SeriesMap : BaseMap<Series, int>
{
    public SeriesMap()
    {
        ToTable("Series");

        Property(x => x.Name).IsRequired();
        Property(x => x.CreateDateTime).IsRequired();
        Property(x => x.ChangeDateTime).IsOptional();

        HasRequired(x => x.Iterations).WithMany().HasForeignKey(x => x.IterationsId).WillCascadeOnDelete(true);
        HasRequired(x => x.K).WithMany().HasForeignKey(x => x.KId).WillCascadeOnDelete(true);
        HasRequired(x => x.Lambda).WithMany().HasForeignKey(x => x.LambdaId).WillCascadeOnDelete(true);
        HasRequired(x => x.Gradient).WithMany().HasForeignKey(x => x.GradientId).WillCascadeOnDelete(true);
        HasRequired(x => x.Improve).WithMany().HasForeignKey(x => x.ImproveId).WillCascadeOnDelete(true);
        HasRequired(x => x.Training).WithMany().HasForeignKey(x => x.TrainingId).WillCascadeOnDelete(true);
    }
}

public class ArgumentMap : BaseMap<Argument, int>
{
    public ArgumentMap()
    {
        ToTable("Argument");

        Property(x => x.Min).IsRequired();
        Property(x => x.Max).IsRequired();
        Property(x => x.Step).IsRequired();

        HasMany(x => x.Values);
    }
}

但是当我尝试创建这样的模型时,我有一条消息异常:

在表'Series'上引入FOREIGN KEY约束'FK_dbo.Series_dbo.Argument_ImproveId'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 .

当我改变

.WillCascadeOnDelete(true);

.WillCascadeOnDelete(false);

模型创建但不是我想要的 . 是否有可能使用级联更新/删除对同一个表进行muplite引用?

1 回答

  • 1

    基本上,SQL Server不允许在内部关系上创建级联操作 - 当级联路径从表A中的列col1到表A中的列col2时(A => A) .

    因此,对此关系强制执行级联删除的唯一方法是直接在SQL数据库上使用SQL-Triggers,或者迭代集合并删除所有子对象 .

    希望能帮助到你!

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