如何在房间里制作组合钥匙 [英] How to make composite key in Room

问题描述

我刚在房间里找到@PrimaryKey批注.那么，如果我想制作组合键，该怎么做?

I have just found @PrimaryKey annotation in room. So If I want to make composite key so how can I do that?

推荐答案

使用primaryKeys().

Room的

Android开发人员文档状态:

如果在Embeddeded字段上使用PrimaryKey批注，则所有列 从该嵌入式字段继承的内容成为复合主键 (包括其大子域).

If PrimaryKey annotation is used on a Embeddedd field, all columns inherited from that embedded field becomes the composite primary key (including its grand children fields).

使用Java的示例实现:

Example implementation in Java:

@Entity(primaryKeys = {"column1","column2","column3"})
class DummyClass {
    ...
}

以 Lalit Kushwah 为例.

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