MongoDB的：数组排序 [英] MongoDB: sorted arrays

问题描述

考虑下面的MongoDB的文档：

  SomeObject {
    nested_objects_ids：
        的ObjectId（1 ...），
        的ObjectId（2 ...），
        ...
        的ObjectId（N ...）
    ]
}
 

nested_object_ids 的长度没有限制。
有一种优雅的方式来继续推动任意值（即的ObjectID）后排序的 nested_object_ids 数组？

感谢您！

解决方案

  

有一种优雅的方式来继续推动任意值后排序的 nested_object_ids 数组？

不幸的是，没有什么我会考虑优雅。

的 $推命令不能在这里工作。你唯一的选择就是整个子阵列拉入客户端，然后将其与重新写了 $设置。

老实说，当谈到与对象数组，MongoDB的功能有限。你可以用 $推， $拉更新，你可以对一个对象字段索引，但仅此而已。

这很难更新特定子对象。和查询不返回子对象，而是返回整个文档。你可以过滤下来到返回 nested_object_ids ，但你总是能得到一整套那里。

一个对你的问题：为什么嵌套的对象需要进行排序

Consider the following MongoDB document:

SomeObject {
    nested_objects_ids : [
        ObjectId( "1..." ), 
        ObjectId( "2..." ),
        ...
        ObjectId( "N..." )
    ]
}

The length of nested_object_ids is not limited. Is there an elegant way to keep the nested_object_ids array sorted after pushing arbitrary values (i.e. ObjectIds)?

Thank you!

解决方案

Is there an elegant way to keep the nested_object_ids array sorted after pushing arbitrary values?

Unfortunately, there is nothing I would consider "elegant".

The $push command does not work here. Your only option is to pull the entire sub-array into the client and then re-write it with a $set.

Honestly, when it comes to dealing with "arrays of objects", MongoDB has limited functionality. You can update with $push, $pull and you can index on an object field, but that's about it.

It's difficult to update a specific sub-object. And querying doesn't return the sub-object, but instead returns the whole document. You could filter it down to returning nested_object_ids, but you always get the whole set there.

A question for you: why do the nested objects need to be sorted?

这篇关于MongoDB的：数组排序的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！