主动Android的许多一对多的关系 [英] Active Android many-to-many relationship

问题描述

虽然这个问题是关于ActiveAndroid，谁是熟悉的ORM也许可以回答这个问题。

Although this question is about ActiveAndroid, anyone who is familiar with ORMs could probably answer this question.

ActiveAndroid似乎并没有给你一个方法做很多一对多的关系，开箱即用。我发现，同时寻找解决的办法是这样的GitHub的问题：<一href="https://github.com/pardom/ActiveAndroid/issues/46">https://github.com/pardom/ActiveAndroid/issues/46

ActiveAndroid doesn't seem to give you a way to do many-to-many relationships out of the box. What I found while searching for a solution was this GitHub issue: https://github.com/pardom/ActiveAndroid/issues/46

据我所知，它是明确创建的关系表，但我不明白怎么下面的部分是应该做的有用的东西：

I understand that it's explicitly creating the relationship table, but I don't understand how the following part is supposed to do anything useful:

public List<Foo> foos() {
    return getMany(Foo.class, "FooBar");
}
public List<Bar> bars() {
    return getMany(Bar.class, "FooBar");
}

这将导致像查询SELECT * FROM foo其中Foo.FooBar = FooBar.Id; 。这将返回最多一个富行。我失去了一些东西？

This would result in a query like SELECT * FROM Foo where Foo.FooBar = FooBar.Id;. This would return at most one Foo row. Am I missing something?

你不需要涉及查询加入？

Don't you need a query involving a join?

推荐答案

假设你要选择所有FOOS为一个特定的酒吧，你可以这样做：

Let's say you want to select all Foos for one specific Bar, you would do this:

List<Foo> foos = ((Foo) new Select().from(FooBar.class)
                .where("Foo = ?", this.getId())
                .executeSingle()).foos();

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