如何为具有关系的多个表创建迁移。

Question

我有 4 张表，我想与这些表建立关系。

模型 1 类别

public partial class Categories
    {
        public Categories()
        {
            AssetTypes = new HashSet<AssetTypes>();
            CategoryComponents = new HashSet<CategoryComponents>();
            Items = new HashSet<Items>();
        }
    public int CategoryId { get; set; }
    public DateTime? Deletedon { get; set; }
    public string Name { get; set; }
    public DateTime CreatedOn { get; set; }

    public virtual ICollection<AssetTypes> AssetTypes { get; set; }
    public virtual ICollection<CategoryComponents> CategoryComponents { get; set; }
    public virtual ICollection<Items> Items { get; set; }
}

这是模型 2 类别组件

public partial class CategoryComponents
    {
        public CategoryComponents()
        {
            AssetComponents = new HashSet<AssetComponents>();
        }

    public int Id { get; set; }
    public string Name { get; set; }
    public int CategoryId { get; set; }

    public virtual Categories Category { get; set; }
    public virtual ICollection<AssetComponents> AssetComponents { get; set; }
}

模型 3“资产类型”

public partial class AssetTypes
    {
        public AssetTypes()
        {
            AssetComponents = new HashSet<AssetComponents>();
            Checkins = new HashSet<Checkins>();
        }

        public int Id { get; set; }
        public string Type { get; set; }
        public string AssetName { get; set; }
        public int AssetStatus { get; set; }
        public string ImagePath { get; set; }
        public int VendorId { get; set; }
        public int CategoryId { get; set; }
        public DateTime CreatedOn { get; set; }
        public DateTime? DeletedOn { get; set; }
        public string Description { get; set; }
        public bool? ActiveStatus { get; set; }
        public int SubCategoryId { get; set; }
        public decimal Price { get; set; }

        public virtual Categories Category { get; set; }
        public virtual SubCategory SubCategory { get; set; }
        public virtual Vendors Vendor { get; set; }
        public virtual AssetTracks AssetTracks { get; set; }
        public virtual ICollection<AssetComponents> AssetComponents { get; set; }
        public virtual ICollection<Checkins> Checkins { get; set; }
    }

模型 4“资产组件”

 public partial class AssetComponents
    {
        public int Id { get; set; }
        public string Value { get; set; }
        public int AssetTypeId { get; set; }
        public string Note { get; set; }
        public int CategoryComponentId { get; set; }

        public virtual AssetTypes AssetType { get; set; }
        public virtual CategoryComponents CategoryComponent { get; set; }
    }

当我添加迁移然后获取错误

在表 'AssetComponents' 上引入 FOREIGN KEY 约束 'FK_AssetComponents_CategoryComponents_CategoryComponentId' 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。 无法创建约束或索引。 请参阅以前的错误。

public virtual DbSet<Categories> Categories { get; set; }
public virtual DbSet<CategoryComponents> CategoryComponents { get; set; }
public virtual DbSet<AssetComponents> AssetComponents { get; set; }
public virtual DbSet<AssetTypes> AssetTypes { get; set; }

任何人都可以为我做一个数据库。Plzzzz

我正在等待任何身体反应。如果我错过了同样的事情，请告诉我。

Answer 1

您可以考虑添加 Restrict onDelete 作为行为。

 modelBuilder.HasOne(x => x....).WithMany(op => op.....).IsRequired()
            .HasForeignKey(@"FkId").OnDelete(DeleteBehavior.Restrict);

Answer 2

对于CategoryComponents和AssetComponents之间的关系，是一对多的关系。

尝试更改public int CategoryComponentId { get; set; } public int CategoryComponentId { get; set; } public int CategoryComponentId { get; set; }到public int? CategoryComponentId { get; set; } public int? CategoryComponentId { get; set; } public int? CategoryComponentId { get; set; }解决这个错误。