我正在尝试为每个子类做表：使用 NHibernate.Mapping.Attributes 的鉴别器。hbm 应该如下所示：
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">
<subclass name="SalesReport" discriminator-value="SalesReport" extends="Report">
<join table="SalesReport">
<key foreign-key="FK_SalesReport_Document" />
<property name="TotalSales" />
<property name="NetGrouth" />
</join>
</subclass>
</hibernate-mapping>
代码如下所示：
[Subclass(NameType=typeof(SalesReport),
DiscriminatorValueObject=DocumentDiscriminator.SalesReport,
ExtendsType=typeof(Report))]
[Serializable]
public partial class SalesReport : Common.Documents.Report
{
[Join(Table = "SalesReport")]
[Key(1, ForeignKey = "FK_SalesReport_Document")]
[Property(2)]
public virtual decimal TotalSales
{
get;
set;
}
[Join(Table = "SalesReport")]
[Key(1, ForeignKey = "FK_SalesReport_Document")]
[Property(2)]
public virtual decimal NetGrouth
{
get;
set;
}
}
结果是这样的：
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">
<subclass name="SalesReport" discriminator-value="SalesReport" extends="Report">
<join table="SalesReport">
<key foreign-key="FK_SalesReport_Document" />
<property name="TotalSales" />
</join>
<join table="SalesReport">
<key foreign-key="FK_SalesReport_Document" />
<property name="TotalSales" />
<property name="NetGrouth" />
</join>
</subclass>
</hibernate-mapping>
它创建了正确的表结构（一个表有两个十进制字段和一个 PF/FK 到 Reports 表），但是在插入数据时它失败了，因为它为每个字段生成了两个插入：
NHibernate: INSERT INTO SalesReport (TotalSales, SalesReport) VALUES (@p0, @p1);@p0 = 13400,20, @p1 = 41
NHibernate: INSERT INTO SalesReport (NetGrouth, SalesReport) VALUES (@p0, @p1);@p0 = 0, @p1 = 41
有没有办法使用 NHibernate.Mapping.Attributes 完成这项工作？