从具有额外字段的一对多表设计类
如何将数据库中的一对多关系中的任何其他属性建模回类中？
例如我有 3 个表 Model、Manager 和 Model_Manager。 Model_Manager 表具有 ModelId、ManagerId 和两个额外属性 - Percentage 和 Owner。
首先，我创建了两个类 Manager 和 Model，Model 类包含一组 Manager 来捕获 1-Many 链接。
但现在我应该把额外的百分比和所有者属性放在哪里。 即使它不是“实际业务”类，在设计中实际使用 Model_Manager 类是否有意义？
How do I model any additional properties from One-Many relationships in the database back into classes?
For example I have 3 tables Model, Manager and Model_Manager. The Model_Manager table has ModelId, ManagerId and two extra properties - Percentage and Owner.
At first I created two classes Manager and Model and the Model class contains a collection of Managers to capture the 1-Many link.
But now where do I put the additional Percentage and Owner properties. Does it make sense to actually have a Model_Manager class in the design even if it's not a "real-business" class?
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这是带有额外数据的多对多关系。 这通常被建模为两个一对多关系。 所以，是的，您确实需要有一个 Model_Manager 类，尽管您可能会考虑一个更好的名称（ManagedModel？）。 Model 和 Manager 各自与 Model_Manager 具有一对多关系。
This is a many-to-many-relationship with extra data. This is typically modeled as two one-to-many relationships. So yes, you do need to have a Model_Manager class, though you might consider a better name (ManagedModel?). Model and Manager each have a one-to-many relationship with Model_Manager.
听起来您的附加 2 个属性是链接属性，因此应该在模拟 managerID 和 2 个附加字段的类中表示
It sounds like your additional 2 properties are link attributes and should therefore be represented in a class that models the managerID and the 2 addtional fields
好吧，想必每个管理器都有一组可以管理一定比例的模型，所以...
我将创建一个 ManagedModel 类，其中包含指向模型对象的指针和附加属性。 然后每个 Manager 可以有一组 ManagedModel 对象。
Well, presumably every Manager has a set of Models that it can manage a percentage of, so...
I would create a ManagedModel class that contains a pointer to a Model object and the additional properties. Then each Manager could have a set of ManagedModel objects.
是的，根据您的描述，ModelManager 类是有道理的。 然后，模型将具有 ModelManager 列表，并且 ModelManager 类将具有经理、百分比和所有者。
Yes, from what you described, a ModelManager class, makes sense. The Model would then have a List of ModelManagers and the ModelManager class would have the Manager, Percentage and Owner.