删除子类也会删除父类

发布于 2024-10-06 04:23:12 字数 866 浏览 2 评论 0原文

我遇到的情况是每个子类使用一个表进行关联。在我尝试从子类表中删除记录之前，映射都很好。删除原因不仅是子类被删除，还包括父类。我可以理解这个功能可能是设计使然，但是有没有办法只删除子类呢？

这是我的示例代码。


public class ParentClassMap : ClassMap<Parent>
{
    public ParentClassMap ()
    {
        Table("tblParent");
        Id(x => x.ParentId).Column("ParentId").GeneratedBy.Identity()
        ... other properties
    }
}

public class ChildClassMap : SubClassMap<Child>
{
    public ChildClassMap()
    {
        Table("tblChild");
        KeyColumn("ParentId");
        ... other properties
    }
}

现在，当我查询记录时，一切看起来都很好，


Child child = session.CreateCriteria<Parent>().Add(Restrictions.Eq("ParentId", 1)).UniqueResult<Parent>();

但是当我删除子项时，执行的 SQL 包括对引用父项或子项的所有表的更新，然后删除子项，然后删除父项。


session.Delete(child);

我只想删除子对象，这可能吗？

原文

I have a situation where I'm using a table per subclass for association. The mappings are fine until I try and delete a record from the subclass table. The delete cause's not only the subclass to be deleted, but also the parent. I can understand this feature may be by design, but is there anyway to just delete the subclass?

Here's my sample code.


public class ParentClassMap : ClassMap<Parent>
{
    public ParentClassMap ()
    {
        Table("tblParent");
        Id(x => x.ParentId).Column("ParentId").GeneratedBy.Identity()
        ... other properties
    }
}

public class ChildClassMap : SubClassMap<Child>
{
    public ChildClassMap()
    {
        Table("tblChild");
        KeyColumn("ParentId");
        ... other properties
    }
}

Now when I query for a record, everything seems fine


Child child = session.CreateCriteria<Parent>().Add(Restrictions.Eq("ParentId", 1)).UniqueResult<Parent>();

But when I delete the child, the sql executed includes updates to all tables that reference either Parent or Child, then the deletion of Child then Parent.