使用查找表进行映射 [英] Mapping with a Lookup Table

问题描述

问题：

我已经看到了一些建模表每个层次结构继承的例子：

联系表

- 名称

- ContactType

字段ContactType包含字符串" Customer"和"员工"。这些示例建议创建2个继承自Contact的类，并添加一个条件，当ContactType =" Customer"然后该课程是客户，当
时，ContactType =  "员工"然后是员工类。接下来的步骤是创建Contact Class Abstract，然后从Contact Table中删除ContactType字段。

问题：

这样可行如果ContactType字段与任何内容无关。我的问题是我的ContactType字段与ContactType表有关。当我在我的桌子上使用上述步骤时，然后 从联系表中删除ContactType字段，编译器
抱怨ContactType和Contact之间的关联没有被corectly映射。当我打开关联时，ContactType.ContactType字段被映射，但是当我在下拉列表中选择将其映射到联系表中的字段时，ContactType字段
显然是丢失的，因为我删除了它。

你如何使这项工作？

谢谢

-Eric

 

 

解决方案

我们不支持映射框。您必须使用查询/定义查询查询和存储过程/函数进行更新/删除/插入操作。

谢谢

Srikanth

Problem:

I have seen a number of examples for modeling Table per Hierarchy inheritance:

Contact Table

- Name

- ContactType

The field ContactType contains strings "Customer" and "Employee". The examples suggest creating 2 classes that inherit from Contact and add a condition that when ContactType = "Customer" then the class is a customer and when ContactType =  "Employee" then an Employee class. The next step is to then make the Contact Class Abstract, and then delete the ContactType field from the Contact Table.

Problem:

This works ok if the ContactType field isn't related to anything. My problem is my ContactType field is related to a ContactType Table. When I use the above steps with my table, and then  delete the ContactType field from the contact table the compiler complains that association between ContactType and Contact isn't mapped corectly. When I open the association the ContactType.ContactType field is mapped, but when I select in the dropdown to map it with the field in the Contact Table, the ContactType field is obviously missing, because I deleted it.

How do you make this work?

Thanks

-Eric

 

 

解决方案

We don't support the mapping out of the box. You would have to use views/defining query for queries and stored procs/ functions for update/delete/insert operations.

Thanks

Srikanth

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