ActiveRecord的查找所有不是由ID排序？ [英] ActiveRecord Find All not sorting by ID?

问题描述

我在Heroku的部署，我似乎无法复制本地有一个奇怪的问题。基本上，当我发现所有在一个特定的模式，而不是通过ID进行排序，似乎他们没有秩序可言回报。

I've got a strange issue on a Heroku deployment that I can't seem to duplicate locally. Basically when I find all on a specific model instead of sorting by ID it seems to return them in no order at all.

通常情况下，记录出来，像这样：

Typically the records come out like so:

>> Model.all

=> [<model id: 2>,<model id: 1>,<model id: 3>,<model id: 4>,<model id: 5>]

...等等。

... and so on.

如果我明确地调用 Model.order（ID ASC）返回模型预期。

If I explicitly call Model.order("id ASC") it returns the models as expected.

怎么办？为什么会找到所有不返回的对象按降序ID顺序？

What gives? Why would find all not return the objects in descending ID order?

推荐答案

排序方式ID是的没有的默认保证的，因为它是由数据库如何无序查询被下令（通常是未指定）。你可以把它总是在顶部定义默认范围订购你的模型像这样：

Ordering by ID is not guaranteed by default, since it’s up to the database how a non-ordered query gets ordered (typically it’s unspecified). You can make it always be ordered by defining a default scope at the top of your model like so:

default_scope order('id ASC')

然后调用 Model.all 将相当于调用 Model.order（'身份证ASC'）。

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