Fluent API 问题 - 多重性在角色中无效

Question

我正在尝试解决这个问题； (Ef6)

我有三个表，“Goal”、“GoalType”、“GoalBudget”。我在 Goal 和 GoalType 之间有一对一的关系，它工作正常，但是当我对 GoalBudget 做同样的事情时，它不起作用 - 当我“更新数据库”时，我收到这个错误：

Goal_GoalBudget_Source：：多重性在关系“Goal_GoalBudget”中的角色“Goal_GoalBudget_Source”中无效。因为从属角色是指关键属性，所以从属角色的多重性的上限必须是'1'。

有什么问题 - 非常感谢

public class Goal
{
    public int GoalId {get;set;}
    public string Name { get; set; }
    public string Description { get; set; }
    public decimal TargetAmount { get; set; }

    public int GoalBudgetId { get; set; }
    public int GoalTypeId { get; set; }
    // Navigaiton Properties
    public virtual GoalType GoalType { get; set; }
    public virtual GoalBudget GoalBudget{ get; set; }
}

public class GoalBudget
{
    public GoalBudget()
    {
        Goals = new List<Goal>();
    }
    public int GoalBudgetId { get; set; }
    public DateTime Created { get; set; }
    // Navigation Property
    public ICollection<Goal> Goals { get; set; }
}

public class GoalType
{
    public GoalType()
    {
        Goals = new List<Goal>();
    }
    public int GoalTypeId {get;set;}
    public string Name { get; set; }
    // Navigation Property
    public ICollection<Goal> Goals { get; set; }
}

配置是：

protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
        // GOAL 
        modelBuilder.Entity<Goal>().Property(n => n.GoalId).IsRequired();
        modelBuilder.Entity<Goal>().Property(n => n.GoalId).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
        modelBuilder.Entity<Goal>().Property(n => n.Name).IsRequired();
        modelBuilder.Entity<Goal>().Property(n => n.Name).HasMaxLength(50);
        modelBuilder.Entity<Goal>().Property(n => n.TargetAmount).IsRequired();

        //-
        modelBuilder.Entity<Goal>().HasKey(k => k.GoalId);
        modelBuilder.Entity<Goal>().HasRequired(o => o.GoalType).WithMany(o => o.Goals).HasForeignKey(k => k.GoalTypeId) ;
        modelBuilder.Entity<Goal>().HasRequired(o => o.GoalBudget).WithMany(o => o.Goals).HasForeignKey(k => k.GoalId);

        // GOAL TYPE
        modelBuilder.Entity<GoalType>().HasKey(k => k.GoalTypeId);
        // GOAL BUDGET
        modelBuilder.Entity<GoalBudget>().Property(n => n.GoalBudgetId).IsRequired();
        modelBuilder.Entity<GoalBudget>().Property(n => n.GoalBudgetId).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
        modelBuilder.Entity<GoalBudget>().Property(n => n.Created).IsRequired();
        modelBuilder.Entity<GoalBudget>().HasKey(k => k.GoalBudgetId);

Answer 1

您的 FluentAPI 映射有错误：

modelBuilder.Entity<Goal>()
    .HasRequired(o => o.GoalBudget)
    .WithMany(o => o.Goals)
    .HasForeignKey(k => k.GoalId);

您的HasForeignKey 方法配置了错误的外键列（GoalId），应该改为GoalBudgetId。

试试：

modelBuilder.Entity<Goal>()
    .HasRequired(o => o.GoalBudget)
    .WithMany(o => o.Goals)
    .HasForeignKey(k => k.GoalBudgetId);