如何按自定义顺序对 Mongo 中的数据进行排序 [英] How to sort data in Mongo in a custom order
问题描述
如何使用 Mongo 功能对这些数据进行排序:
输入
{ "_id" : 1, "domainName" : "test1.com", "hosting" : "hostgator.com" }{_id":2，域名":test2.com"，托管":aws.amazon.com"}{_id":3，域名":test3.com"，托管":aws.amazon.com"}{_id":4，域名":test4.com"，托管":hostgator.com"}{_id":5，域名":test5.com"，托管":aws.amazon.com"}{_id":6，域名":test6.com"，托管":cloud.google.com"}{_id":7，域名":test7.com"，托管":aws.amazon.com"}{_id":8，域名":test8.com"，托管":hostgator.com"}{_id":9，域名":test9.com"，托管":cloud.google.com"}{_id":10，域名":test10.com"，托管":godaddy.com"}按托管字段的顺序，获取结果，例如按以下顺序:
1) 首先 - 所有godaddy;
2) 其次 - 所有 AWS;
3) 然后是其他一切.
输出
<代码>{结果" : [{_id":10，"域名": "test10.com",托管":godaddy.com"},{_id":2，"域名": "test2.com",托管":aws.amazon.com"},{_id":3，"域名": "test3.com",托管":aws.amazon.com"},{_id":5，"域名": "test5.com",托管":aws.amazon.com"},{_id":7，"域名": "test7.com",托管":aws.amazon.com"},{_id":1，"域名": "test1.com",托管":hostgator.com"},{_id":4，"域名": "test4.com",托管":hostgator.com"},{_id":6，"域名": "test6.com",托管":cloud.google.com"},{_id":8，"域名": "test8.com",托管":hostgator.com"},{_id":9，"域名": "test9.com",托管":cloud.google.com"},]}在这个例子中，我想以更相关的方式为用户返回结果.在原始任务中，我想使用其他一些提供附加信息的集合对其进行排序.
但是如果你帮助我完成之前的任务就足够了吗?
UPD:关于问题的第二部分.
另一个任务是如何从一个集合中返回可排序的数据，并依赖于另一个集合.
示例:
第一个集合与之前给出的相同:
{ "_id" : 1, "domainName" : "test1.com", "hosting" : "hostgator.com" }...第二个集合，提供一些关于托管的额外信息:
{ '_id': 123, 'quality':'best', 'hostings': ["hostgator.com", "aws.amazon.com"]},{ '_id': 321, 'quality':'good', 'hostings': ["cloud.google.com"]},{ '_id': 345, 'quality':'bad', 'hostings': ["godaddy.com"]},结果，我需要按以下顺序从第一个收集数据返回:
1) 首先所有好的主机2)其次一切都好3) 第三个都不好
输出:
<代码>{结果" : [//最好的:{_id":1，"域名": "test1.com",托管":hostgator.com"},{_id":4，"域名": "test4.com",托管":hostgator.com"},{_id":8，"域名": "test8.com",托管":hostgator.com"},{_id":2，"域名": "test2.com",托管":aws.amazon.com"},{_id":3，"域名": "test3.com",托管":aws.amazon.com"},{_id":5，"域名": "test5.com",托管":aws.amazon.com"},{_id":7，"域名": "test7.com",托管":aws.amazon.com"},//好的:{_id":9，"域名": "test9.com",托管":cloud.google.com"},{_id":6，"域名": "test6.com",托管":cloud.google.com"},//坏的{_id":10，"域名": "test10.com",托管":godaddy.com"}]}更新 2
我在前面的例子中得到了很好的答案和例子.非常感谢！但我举了另一个例子.
我需要比较 3 个集合的 ID 以按顺序排序 - 第一个:朋友，第二个:'请求'，以及:其他用户.
输入
db.friends.find({userId: currentUser});//{"_id" : "PgC7LrtaZtQsShtzT", "userId" : "tHuxnWxFLHvcpRgHb", "friendId" : "jZagPF7bd4aW8agXb",}db.requests.find({userId: currentUser});//看起来像朋友，但带有 'requesterId'现在我需要聚合用户"集合，定义与前两个集合(朋友、请求)匹配的分数.
使用提供的答案，我管理了结果，但只有一个集合.我怎样才能用 3 个或多个来做这个?
您可以将每个 hosting 投影到由整数表示的单独类型，最后对这些整数进行排序.在下面的聚合管道中说明
How I can sort this data, using Mongo functionality:
Input
{ "_id" : 1, "domainName" : "test1.com", "hosting" : "hostgator.com" }
{ "_id" : 2, "domainName" : "test2.com", "hosting" : "aws.amazon.com"}
{ "_id" : 3, "domainName" : "test3.com", "hosting" : "aws.amazon.com" }
{ "_id" : 4, "domainName" : "test4.com", "hosting" : "hostgator.com" }
{ "_id" : 5, "domainName" : "test5.com", "hosting" : "aws.amazon.com" }
{ "_id" : 6, "domainName" : "test6.com", "hosting" : "cloud.google.com" }
{ "_id" : 7, "domainName" : "test7.com", "hosting" : "aws.amazon.com" }
{ "_id" : 8, "domainName" : "test8.com", "hosting" : "hostgator.com" }
{ "_id" : 9, "domainName" : "test9.com", "hosting" : "cloud.google.com" }
{ "_id" : 10, "domainName" : "test10.com", "hosting" : "godaddy.com" }
In order by hosting field, to get result, for example in this order:
1) First - all godaddy;
2) Second - all AWS;
3) and next, everything else.
Output
{
"result" : [
{
"_id" : 10,
"domainName" : "test10.com",
"hosting" : "godaddy.com"
},
{
"_id" : 2,
"domainName" : "test2.com",
"hosting" : "aws.amazon.com"
},
{
"_id" : 3,
"domainName" : "test3.com",
"hosting" : "aws.amazon.com"
},
{
"_id" : 5,
"domainName" : "test5.com",
"hosting" : "aws.amazon.com"
},
{
"_id" : 7,
"domainName" : "test7.com",
"hosting" : "aws.amazon.com"
},
{
"_id" : 1,
"domainName" : "test1.com",
"hosting" : "hostgator.com"
},
{
"_id" : 4,
"domainName" : "test4.com",
"hosting" : "hostgator.com"
},
{
"_id" : 6,
"domainName" : "test6.com",
"hosting" : "cloud.google.com"
},
{
"_id" : 8,
"domainName" : "test8.com",
"hosting" : "hostgator.com"
},
{
"_id" : 9,
"domainName" : "test9.com",
"hosting" : "cloud.google.com"
},
]
}
With this example i want to return results in more relevant way for user. And in origanl task I want to sort this using few another collections, which serve additional information.
But will be good enough if you helps me with previous task?
UPD: About second part of question.
One more task is how to return sortable data from one collection in dependence of another.
Example:
first collection the same which was given before:
{ "_id" : 1, "domainName" : "test1.com", "hosting" : "hostgator.com" }
...
second collection, provide some additional info about hosting:
{ '_id': 123, 'quality':'best', 'hostings': ["hostgator.com", "aws.amazon.com"]},
{ '_id': 321, 'quality':'good', 'hostings': ["cloud.google.com"]},
{ '_id': 345, 'quality':'bad', 'hostings': ["godaddy.com"]},
And in result, I need to return from first collection data in this order:
1) First all good hostings 2) second all good 3) third all bad
Output:
{
"result" : [
//Best:
{
"_id" : 1,
"domainName" : "test1.com",
"hosting" : "hostgator.com"
},
{
"_id" : 4,
"domainName" : "test4.com",
"hosting" : "hostgator.com"
},
{
"_id" : 8,
"domainName" : "test8.com",
"hosting" : "hostgator.com"
},
{
"_id" : 2,
"domainName" : "test2.com",
"hosting" : "aws.amazon.com"
},
{
"_id" : 3,
"domainName" : "test3.com",
"hosting" : "aws.amazon.com"
},
{
"_id" : 5,
"domainName" : "test5.com",
"hosting" : "aws.amazon.com"
},
{
"_id" : 7,
"domainName" : "test7.com",
"hosting" : "aws.amazon.com"
},
// Good:
{
"_id" : 9,
"domainName" : "test9.com",
"hosting" : "cloud.google.com"
},
{
"_id" : 6,
"domainName" : "test6.com",
"hosting" : "cloud.google.com"
},
//Bad
{
"_id" : 10,
"domainName" : "test10.com",
"hosting" : "godaddy.com"
}
]
}
UPDATE 2
I get good answer and example on previous example. Thank you so much! But I stack with another example.
I need to compare IDs of 3 collections to sort in order - first: friend, second: 'requests', and: other users.
Input
db.friends.find({userId: currentUser});
// {"_id" : "PgC7LrtaZtQsShtzT", "userId" : "tHuxnWxFLHvcpRgHb", "friendId" : "jZagPF7bd4aW8agXb",}
db.requests.find({userId: currentUser});
// looks like friend but with 'requesterId'
And now I need to aggregate 'users' collection, define the score which matches with previous two collections (friends, requests).
Using provided answer, I managed result but only with one collection. How can I make this with 3 or multiple?
You can project each of the hosting into separate type denoted by integers, and finally sort on these integers. Illustrated in the aggregation pipeline below
[
{$lookup: {
from: 'secondCollectionStoringQuality',
localField: 'hosting',
foreignField: 'hostings',
as: 'nw'
}},
{$unwind: '$nw'},
{$project: {
domainName: 1,
hosting: 1,
type: {
$cond: [
{$eq: ['$nw.quality', 'best']},
0,
{$cond: [
{$eq: ['$nw.quality', 'good']},
1,
2
]}
]
}
}},
{$sort: {type: 1}}
]
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