我非常想从这个查询中得到想要的东西...但是现在我想在通知字段上排序
NOTE：这是一种改进：我现在要问如何返回通知字段上的SORT，而我类似的question问如何返回数据一个开始和结束日期，而我的另一个类似的question询问如何返回仅某些字段。
const mongoose = require('mongoose');
const Schema = mongoose.Schema;
const RegisterSchema = new Schema({
userId: {type: Schema.Types.ObjectId, required: true},
accessToken: {type:String, required: true, default: null},
})
module.exports = Register = mongoose.model( 'register', RegisterSchema)
这里有一些寄存器数据
[
{
"_id": "Reg_1",
"userId": "User_1",
"accessToken": "111"
},
{
"_id": "Reg_2",
"userId": "User_2",
"accessToken": "222"
}
]
下一个文档包含通过accessToken与注册架构相关的数据
const mongoose = require('mongoose');
const Schema = mongoose.Schema;
const NotificationSchema = new Schema({
accessToken: {type:String, required: true},
summaryId: {type:Number, required: true},
dateCreated: {type: Date, default: Date.now},
// I don't want these returned in the final results
dontWantThis1: {type:Number, required: true},
dontWantThis2: {type:Number, required: true},
})
module.exports = Notification = mongoose.model( 'notification', NotificationSchema)
这里有一些通知数据
[{
"_id": "N1_1",
"accessToken": "111",
"summaryId": 1111,
"dontWantThis1": 61,
"dontWantThis2": 62,
"dateCreated": "2020-04-17T00:00:00.000+00:00" },
{
"_id": "N2_1",
"accessToken": "222",
"summaryId": 2221,
"dontWantThis1": 71,
"dontWantThis2": 72,
"dateCreated": "2020-04-18T00:00:00.000+00:00" },
{
"_id": "N1_2",
"accessToken": "111",
"summaryId": 1112,
"dontWantThis1": 611,
"dontWantThis2": 622,
"dateCreated": "2020-05-25T00:00:00.000+00:00" },
{
"_id": "N2_2",
"accessToken": "222",
"summaryId": 2222,
"dontWantThis1": 711,
"dontWantThis2": 722,
"dateCreated": "2020-05-26T00:00:00.000+00:00" }
]
此代码返回我想要的所有内容...，但不按日期创建的日期对通知进行sort优先显示，首先显示最新日期。
// make sure the input dates are REALLY date objects
// I only want to see notifications for the month of May (in this example)
var dateStart = new Date('2020-01-01T00:00:00.000+00:00');
var dateEnd = new Date('2020-05-30T00:00:00.000+00:00');
var match = {$match: { userId: mongoose.Types.ObjectId(userId) } };
var lookup ={
$lookup:
{
from: "my_Notifications",
localField: "accessToken",
foreignField: "accessToken",
as: "notifications"
}
};
var dateCondition = { $and: [
{ $gte: [ "$$item.dateCreated", dateStart ] },
{ $lte: [ "$$item.dateCreated", dateEnd ] }
]}
var project = {
$project: {
notifications: {
$filter: {
input: "$notifications",
as: "item",
cond: dateCondition
} } }
};
var project2 = {
$project: {
"_id": 1,
"userId": 1,
"accessToken":1,
"count":{$size:"$notifications"},
"notifications._id":1,
"notifications.summaryId": 1,
"notifications.dateCreated":1,
"notifications.dateProcessed":1,
}
};
var agg = [
match,
lookup,
project,
project2,
];
Register.aggregate(agg)
.then( ..... )
我想按最新日期至最早日期对通知进行排序
我想是 $sort: {dateCreated:-1}
NOTE：哪个“ accessToken”是第一个记录都没有关系……只是通知的日期EACH accessToken记录中的>是最早的。
[ { "_id": "Reg_1", "accessToken": "111", "count": 2, "notifications": [ { "_id": "N1_2", "dateCreated": ISODate("2020-05-25T00:00:00Z"), "summaryId": 1112 }, { "_id": "N1_1", "dateCreated": ISODate("2020-04-17T00:00:00Z"), "summaryId": 1111 } ], "userId": "User_1" }, { "_id": "Reg_2", "accessToken": "222", "count": 2, "notifications": [ { "_id": "N2_2", "dateCreated": ISODate("2020-05-26T00:00:00Z"), "summaryId": 2222 }, { "_id": "N2_1", "dateCreated": ISODate("2020-04-18T00:00:00Z"), "summaryId": 2221 } ], "userId": "User_2" } ]尝试1
我认为这就像在管道中添加排序一样简单：
var sort = { $sort: {dateCreated:-1} }; var agg = [ match, lookup, project, project2, sort, ];无效
我以为可能是因为我没有使用通知字段？
var sort = { $sort: { "notifications.dateCreated":-1, // newest date first ! } }; var agg = [ match, lookup, project, project2, sort, ];no ..
我使用了mongodb playground（来自我的最后一个问题），并进行了排序...确实可行...但是我希望该排序对返回的通知进行排序[[PER注册，] >尝试4
尝试5
var sort = {
$project: {
notifications: {
$sort: {
"notifications.dateCreated":1,
}
}
}
};
var agg = [
match,
lookup,
project,
sort,
project2,
];
got this error
\"Unrecognized expression '$sort'\"
尝试6
尝试6个预期的输出
[
{
"_id": "Reg_2",
"accessToken": "a_2",
"userId": "User_2",
"notifications": [
{
"_id": "N2_2",
"dateCreated": "2020-05-26T00:00:00.000+00:00",
"summaryId": 2222
},
{
"_id": "N2_1",
"dateCreated": "2020-04-18T00:00:00.000+00:00",
"summaryId": 2221
}
],
"notifications_count": 2
},
{
"_id": "Reg_1",
"accessToken": "a_1",
"userId": "User_1",
"notifications": [
{
"_id": "N1_2",
"dateCreated": "2020-05-25T00:00:00.000+00:00",
"summaryId": 1112
},
{
"_id": "N1_1",
"dateCreated": "2020-04-17T00:00:00.000+00:00",
"summaryId": 1111
}
],
"notifications_count": 2
}
]
尝试6错误输出相反，我得到了这个：
[
{
"_id": {
"accessToken": "a_2",
"userId": "User_2"
},
"notifications": [
{
"_id": "N2_2",
"dateCreated": "2020-05-26T00:00:00.000+00:00",
"summaryId": 2222
},
{
"_id": "N2_1",
"dateCreated": "2020-04-18T00:00:00.000+00:00",
"summaryId": 2221
}
],
"notifications_count": 2
},
{
"_id": {
"accessToken": "a_1",
"userId": "User_1"
},
"notifications": [
{
"_id": "N1_2",
"dateCreated": "2020-05-25T00:00:00.000+00:00",
"summaryId": 1112
},
{
"_id": "N1_1",
"dateCreated": "2020-04-17T00:00:00.000+00:00",
"summaryId": 1111
}
],
"notifications_count": 2
}
]
谢谢！
我非常想从查询中得到想要的内容...但是现在我想在通知字段上进行排序注意：这是一种改进：我现在正在问如何在通知字段上返回SORT，...
db.Register.aggregate([
{
$lookup: {
from: "my_Notifications",
localField: "accessToken",
foreignField: "accessToken",
as: "notifications"
}
},
{
// cartesian product of array lengths
$unwind: "$notifications"
},
{
$sort: {
// Sort the records by created date
"notifications.dateCreated": -1
}
},
{
$group: {
"_id": {
"accessToken": "$accessToken",
"userId": "$userId"
},
"notifications": {
$push: "$notifications"
},
"notifications_count": {
$sum: 1
}
}
}
])