NHibernate Mappings复制列

Question

我遇到了一些非常基本的映射问题，一对多。

类

public class ClaimPerson
{
    public virtual decimal PersonID { get; set; }
    public virtual decimal? WorkerID { get; set; }
    ...

    public virtual ICollection<InjuryClaim> Claims { get; set; }
}

public class InjuryClaim : EntityBase<InjuryClaim>
{
    public virtual decimal ClaimID { get; set; }
    public virtual decimal WorkerID { get; set; }
    ...

    public virtual ClaimPerson Worker { get; set; }
}

映射

public class ClaimPersonMap : ClassMap<ClaimPerson>
{
    public ClaimPersonMap()
    {
        Table("CL_CLAIM_PERSON");

        Id(x => x.PersonID).Column("PERSON_ID");

        Map(x => x.PrimaryFirstName).Column("PRIMARY_FIRST_NAME");
        Map(x => x.PrimaryLastName).Column("PRIMARY_LAST_NAME");

        HasMany(x => x.Claims).AsBag().KeyColumn("WORKER_ID");
    }
}

public class InjuryClaimMap : ClassMap<InjuryClaim>
{
    public InjuryClaimMap()
    {
        Table("CL_INJURY_CLAIM");

        Id(x => x.ClaimID).Column("CLAIM_ID");
    }
}

查询

var people = session.Query<ClaimPerson>()
                .Where(x => x.PrimaryLastName.StartsWith("Strian"))
                .Fetch(x => x.Claims)
                .ToList();

输出（SQL）

SELECT claimperso0_.PERSON_ID AS PERSON1_0_0_,
   claims1_.CLAIM_ID AS CLAIM1_1_1_,
   claimperso0_.PRIMARY_FIRST_NAME AS PRIMARY2_0_0_,
   claimperso0_.PRIMARY_LAST_NAME AS PRIMARY3_0_0_,
   claims1_.WORKER_ID AS WORKER2_0__,
   claims1_.CLAIM_ID AS CLAIM1_0__
FROM    CL_CLAIM_PERSON claimperso0_
   LEFT OUTER JOIN
      CL_INJURY_CLAIM claims1_
   ON claimperso0_.PERSON_ID = claims1_.WORKER_ID
WHERE claimperso0_.PRIMARY_LAST_NAME LIKE (:p0 || '%');

为什么重复claims1_.CLAIM_ID列？