问题描述
这是一个常见的数据库问题，与任何特定的数据库或编程语言无关。
This is a general database question, not related to any particular database or programming language.
我以前做过一些数据库工作，作品。这一次我想为未来做计划。
I've done some database work before, but it's generally just been whatever works. This time I want to plan for the future.
我有一个表存储备件列表。名称，零件号码，位置等。我还需要存储它们也适用的设备。
I have one table that stores a list of spare parts. Name, Part Number, Location etc. I also need to store which device(s) they are applicable too.
一种方法是为每个设备创建一个列在我的备件表。这是如何在当前数据库中完成。一个问题是，如果将来我想添加一个新的设备，我必须创建一个新的列，但它使编程更容易。
One way to do is to create a column for each device in my spare parts table. This is how it's being done in the current database. One concern is if in the future I want to add a new device I have to create a new column, but it makes the programming easier.
我的想法是创建一个单独适用性表。它将存储零件ID和设备ID，如果零件适用于多个设备，它将有多行。
My idea is to create a separate Applicability table. It would store the Part ID and Device ID, if a part is applicable to more than one device it would have more than one row.
Parts
-------
ID
Name
Description
Etc...
PartsApplicability
-------
ID
PartID
DeviceID
Devices
------
ID
Name
我的问题是这是否是一个有效的方法，
My questions are whether this is a valid way to do it, would it provide an advantage over the original way, and is there any better ways to do it?
感谢任何答案。
推荐答案
我同意Rex M的回答，这是一种标准方法。您可以在PartsApplicability表上做的一件事是删除ID列，并使PartID / DeviceID成为复合主键。这将确保您的部件不能多次关联到同一设备，反之亦然。
I agree with Rex M's answer, this is a standard approach. One thing you could do on the PartsApplicability table is remove the ID column, and make the PartID/DeviceID a composite primary key. This will ensure that your Part cannot be associated to the same Device more than once, and vice-versa.
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