c# - 如何处理 EntityDataSource 中的自连接？

Question

我想知道如何处理 EntityDataSource 中的自连接。

如果我有这样的查询:

SELECT b.degree_name ,c.degree_name as degree_next
FROM EMPDEGPROM a INNER JOIN  DEGREEWORK b
ON a.degree_code=b.degree_code
INNER JOIN DEGREEWORK c
ON a.next_degree_code =c.degree_code
WHERE a.emp_num=6777

---

如何将此数据源用作EntityDataSource。？

我尝试这样做，但我无法获得 degree_next

<asp:EntityDataSource ID="EmpPromotionsDS" runat="server"
            ConnectionString="name=CTX" DefaultContainerName="CTX" EnableFlattening="False"
            EntitySetName="EMPDEGPROMs" EntityTypeFilter="EMPDEGPROM" Where="it.EMP_NUM =@emp_num"  Include="DEGREEWORK" >
            <WhereParameters>
                <asp:SessionParameter Name="emp_num" SessionField="emp_num" DbType="Int32" />
            </WhereParameters>

Answer 1

创建 View 。

CREATE VIEW XXX AS
SELECT a.emp_num, b.degree_name ,c.degree_name as degree_next
FROM EMPDEGPROM a INNER JOIN  DEGREEWORK b
ON a.degree_code=b.degree_code
INNER JOIN DEGREEWORK c
ON a.next_degree_code =c.degree_code

EF 从 View 中读取没有问题。