c# - 无法确定复合主键oracle db错误信息如何解决？

Question

人物.cs:

[Table (name : "Person")]
public class Person : BaseEntity
{
    [Key, Column(Order = 0), DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public string PersonNo { get; set; }
    [Key, Column(Order = 1)]
    public string PersonType { get; set; }
    [Key, Column(Order = 2)]
    public string PersonKing { get; set; }
    
    public string Name { get; set; }
    public string Surname { get; set; }
    public DateTime Dates { get; set; }
}

个人 Controller

using(DbContext  _db =new DbContext())
{
   var person = _ db.Person.Where(x=>x.PersonNo=='1000').ToString();
   .
   .
}

语境:

public virtual DbSet<Person> Person { get; set;}

public MyContext(): base("Name=MyDbContext") {  }

public override void OnModelCreating(DbModelBuilder modelBuilder)
{
   modelBuilder.HasDefaultSchema("DB");
}

错误发生在这行代码上:

var person = _ db.Person.Where(x => x.PersonNo == '1000').ToString();

这是错误

Unable to determine composite primary key ordering for type Entity.Person

数据库:Oracle 和 PersonNo、PersonType、PersonKing 列是主键的一部分。

Answer 1

尝试这个:

 var person = _db.Set<Person>().Where(x=>x.PersonNo=='1000').FirstOrDefault();