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 Series 和 Argument 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);
至
.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
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!