How to query from two collections in mongodb using aggregate? - node.js

I have the two following collections in my mongoDB:
PRODUCTS:
[
{
"_id": "5ebb0984e95e3e9e35aab3bf",
"name": "Product 1",
"brand": "ABC",
"code": "7891910000190",
"description": "Lorem Ipsum"
},
{
"_id": "5ebdb9f3d943ae000a4a9714",
"name": "Product 2",
"brand": "DEF",
"code": "7891910000190",
"description": "Lorem Ipsum"
}
]
STOCK GOODS:
[
{
"_id": "5ed0586b7f2cfe02387d0706",
"companyId": "5ed0491bf9a892a5fd9b4d9b",
"branchId": "5ed049a8f9a892a5fd9b4d9e",
"inventoryId": "5ed04d01e9e43cee79734b95",
"productId": "5ebb0984e95e3e9e35aab3bf"
},
{
"_id": "5ed058da75e4e01013f5779d",
"companyId": "5ed0491bf9a892a5fd9b4d9b",
"branchId": "5ed049a8f9a892a5fd9b4d9e",
"inventoryId": "5ed04cede9e43cee79734b93",
"productId": "5ebb0984e95e3e9e35aab3bf"
},
{
"_id": "5ed059483da3bafccb34cec3",
"companyId": "5ed0491bf9a892a5fd9b4d9b",
"branchId": "5ed049a8f9a892a5fd9b4d9e",
"inventoryId": "5ed04d01e9e43cee79734b95",
"productId": "5ebb0984e95e3e9e35aab3bf"
}
]
I want to get the follow result:
[
{
"_id": "5ed0586b7f2cfe02387d0706",
"data": {
"_id": "5ebb0984e95e3e9e35aab3bf",
"brand": "ABC",
"code": "7891910000190",
"description": "Lorem Ipsum",
"name": "Product 1",
}
},
{
"_id": "5ed059483da3bafccb34cec3",
"data": {
"_id": "5ebb0984e95e3e9e35aab3bf",
"brand": "ABC",
"code": "7891910000190",
"description": "Lorem Ipsum",
"name": "Product 1",
}
}
]
My NodeJS and MongoDB aggregate look like this:
const mongoose = require("mongoose");
const StockGoods = mongoose.model("StockGoods");
ObjectId = require("mongodb").ObjectID;
exports.getProducts = async (companyId, branchId, inventoryId) => {
const response = await StockGoods.aggregate([
{
$match: {
companyId: new ObjectId("5ed0491bf9a892a5fd9b4d9b"), // new ObjectId(companyId)
inventoryId: new ObjectId("5ed04d01e9e43cee79734b95"), // new ObjectId(inventoryId)
branchId: new ObjectId("5ed049a8f9a892a5fd9b4d9e"), // new ObjectId(branchId)
},
},
{
$lookup: {
from: "products",
localField: "productId",
foreignField: "_id",
as: "inventory_docs",
},
},
{
$project: {
data: "$inventory_docs",
},
},
{ $unwind: "$data" },
]);
return response;
};
This is the same database and the aggregate function described above, you can check this: https://mongoplayground.net/p/FRgAIfO2bwh.
But, this function aggregate does not working when I use nodejs.
My API returns nothing (empty array).
Whats wrong?

Issue here is the way you have stored data in collection.... StockGoods collection has companyId, inventoryId and branchIdas a string but aggregation is looking for ObjectId aee below match criteria:
$match: {
companyId: new ObjectId("5ed0491bf9a892a5fd9b4d9b"), // new ObjectId(companyId)
inventoryId: new ObjectId("5ed04d01e9e43cee79734b95"), // new
ObjectId(inventoryId)
branchId: new ObjectId("5ed049a8f9a892a5fd9b4d9e"), // new ObjectId(branchId)
},
Based on the data you store in DB either you need to update match with string.
So below Aggregation will work for you..
[
{
"$match": {
"companyId": "5ed0491bf9a892a5fd9b4d9b",
"inventoryId": "5ed04d01e9e43cee79734b95",
"branchId": "5ed049a8f9a892a5fd9b4d9e"
}
},
{
"$lookup": {
"from": "products",
"localField": "productId",
"foreignField": "_id",
"as": "inventory_docs"
}
},
{
"$project": {
"data": "$inventory_docs"
}
},
{
"$unwind": "$data"
}
]
This works you can test in Compass Aggregator tab

[RESOLVED]
The problem was in the scheme:
companyId: {
type: String,
required: true,
},
The correct is:
companyId: {
type: Schema.Types.ObjectId,
required: true,
},

Related

How to make a nested relationship on mongodb?

For example i have 4 collections. There are:
"company" collection
{
"id_company": "C01"
"company_name": "Sidomuncul"
"like": [
"123",
"121"
]
}
"user" collection
{
"id_user": "123",
"name": "Astra",
"major": "111",
"language": [{
"id_language": "101",
"level": "Expert"
}]
},
{
"id_user": "121",
"name": "Bibi",
"id_major": "112",
"language": [{
"id_language": "102",
"level": "Intermediate"
}]
}
"major" collection
{
"id_major": "111",
"name": "IT"
},
{
"id_major": "112",
"name": "Designer"
}
"language" collection
{
"id_language": "101",
"name": "English"
},
{
"id_language": "102",
"name": "Chinese"
}
And when i make a route for get who are like company by id_company "C01", i want show the result relation id_user in "like" field with user collection. Example result:
{
"id_company": C01",
"like": [
{
"id_user": "123",
"name": "Astra",
"major": "IT",
"language": [{
"id_language": "English",
"level": "Expert"
}]
},
{
"id_user": "121",
"name": "Bibi",
"id_major": "Designer",
"language": [{
"id_language": "Chinese",
"level": "Intermediate"
}]
}
] //Close Like Field
}
Thanks before.
SOLVED
Use lookup and group also push
Using Mongo aggregate pipeline you can collect required result in multiple stages. For mongo aggregate query you can use $lookup, $set, $unwind and $group stages. Try this query, you might get required result set:
db.company.aggregate([
{
"$unwind": "$like"
},
{
$lookup: {
from: "user",
localField: "like",
foreignField: "id_user",
as: "like"
}
},
{
"$unwind": "$like"
},
{
$lookup: {
from: "major",
localField: "like.major",
foreignField: "id_major",
as: "major"
}
},
{
"$unwind": "$major"
},
{
$set: {
"like.major": "$major.name"
}
},
{
$lookup: {
from: "language",
localField: "like.language.id_language",
foreignField: "id_language",
as: "lang"
}
},
{
"$unwind": "$lang"
},
{
$set: {
"like.language.id_language": "$lang.name"
}
},
{
$group: {
_id: "id_company",
company_name: {
"$first": "$company_name"
},
like: {
$push: {
id_user: "$like.id_user",
major: "$like.major",
name: "$like.name",
language: "$like.language"
}
}
}
}
])

mongodb aggregate on array of objects

I'm trying to group my participants array in to such a way that for a single participant I should get all the meeting under that participant in an array.
[
{
"_id": "5fc73e7131e6a20f6c492178",
"participants": [
{
"_id": "5fc74bc5e7c54d0ea8f133ca",
"rsvp": "Yes",
"name": "Participant 1",
"email": "participant1#gmail.com"
},
{
"_id": "5fc74e1254b8d337b4ae36d2",
"rsvp": "Not Answered",
"name": "Participant 2",
"email": "participant2#gmail.com"
}
],
"title": "Meeting 1",
"startTime": "2020-11-01T18:30:00.000Z",
"endTime": "2020-11-03T18:30:00.000Z"
},
{
"_id": "5fc73f1cdfc45d3ca0c84654",
"participants": [
{
"_id": "5fc74bc5e7c54d0ea8f133ca",
"rsvp": "Yes",
"name": "Participant 2",
"email": "participant2#gmail.com"
}
],
"title": "Meeting 2",
"startTime": "2020-11-01T18:30:00.000Z",
"endTime": "2020-11-03T18:30:00.000Z"
}
]
my expected result should be like
[{
"participant": {
"_id": "5fc74bc5e7c54d0ea8f133ca",
"rsvp": "Yes",
"name": "Participant 1",
"email": "participant1#gmail.com"
},
meetings: [{meeting1, meeting2, ...and so on}]
},
{
"participant": {
"_id": "5fc74bc5e7c54d0ea8f133ca",
"rsvp": "Yes",
"name": "Participant 2",
"email": "participant2#gmail.com"
},
meetings: [{meeting2, meeting3, ...and so on}]
}
]
I'm kinda stuck for hours to figure it out. I tried the approach by using $group and $unwind but I was getting participants as an array consisting of a single participant(object). and on that I was unable to run $match to match according to the participant's email because participants field was an array.
I tried this
const docs = await Meeting.aggregate([
{ $unwind: '$participants' },
{
$lookup: {
from: 'participants',
localField: 'participants',
foreignField: '_id',
as: 'participants'
}
},
{ $match },
{ $group: { _id: "$participants", meetings: { $push: "$$ROOT" } } },
]);
but this is not matching the expected result which I want it to be.
You can unwind to deconstruct the array and use group to get your desired output
db.collection.aggregate([
{
"$unwind": "$participants"
},
{
$group: {
_id: "$participants._id",
participants: {
$first: "$participants"
},
meetings: {
"$addToSet": "$title"
}
}
}
])
Working Mongo playground

Mongodb, mongoose - Sorting by _id and date using aggregate and group

I am trying to sort by the task._id & date in desc order. I am able to sort by task._id but sortibg bydate doesnt work, I tried changing the order in aggregate still no luck. I get the response but just the order by usertasks were added in collection and not by the usertask.date
User(name, address, etc)
Task(name, icon, assignee)
UserTask(User.ObjectId, Task.ObjectId, date)
User Collection:
{
"users": [
{
"name": "Bill",
"phone": "345"
},
{
"name": "Steve",
"phone": "123"
},
{
"name": "Elon",
"phone": "567"
}
]
}
Task collection:
{
"tasks": [
{
"name": "Run 100m",
"icon": "run",
"assignee": "Elon"
},
{
"name": "Walk 1 hour",
"icon": "walk",
"assignee": "Bill"
},
{
"name": "Jog 30 minutes",
"icon": "jog",
"assignee": "Steve"
}
]
}
UserTasks:
{
"_id": "5e72fec..",
"user": "5e72fa4..",
"task": "5e72fbac..",
"date": "2020-03-03T05:10:10.000Z",
"createdAt": "2020-03-19T05:10:37.027Z",
"updatedAt": "2020-03-19T05:10:37.027Z",
"__v": 0
},
{
"_id": "5e72fed3..",
"user": "5e72fa4e..",
"task": "5e72fbac..",
"date": "2020-03-12T05:10:10.000Z",
"createdAt": "2020-03-19T05:10:43.296Z",
"updatedAt": "2020-03-19T05:10:43.296Z",
"__v": 0
},
{
"_id": "5e72fed6..",
"user": "5e72fa..",
"task": "5e72fb..",
"date": "2020-03-15T05:10:10.000Z",
"createdAt": "2020-03-19T05:10:46.057Z",
"updatedAt": "2020-03-19T05:10:46.057Z",
"__v": 0
},
{
"_id": "5e72feda...",
"user": "5e72fa4..",
"task": "5e72fb..",
"date": "2020-03-07T05:10:10.000Z",
"createdAt": "2020-03-19T05:10:50.785Z",
"updatedAt": "2020-03-19T05:10:50.785Z",
"__v": 0
}
This is the Aggregate that needs changing
UserTask.aggregate([
{
$lookup: {
from: "tasks",
localField: "task",
foreignField: "_id",
as: "matchedTask"
}
},
{
$unwind: "$matchedTask"
},
{
$lookup: {
from: "users",
localField: "user",
foreignField: "_id",
as: "matchedUser"
}
},
{
$unwind: "$matchedUser"
},
{
$group: {
_id: "$matchedTask._id",
name: {$first: "$matchedTask.name"},
icon: {$first: "$matchedTask.icon"},
assignee: { $first: "$matchedTask.assignee" },
userdata: {
$push: {
name: "$matchedUser.name",
date: "$date"
}
}
}
},
{
$sort: { _id: 1, "userdata.date": -1 }
}
])
.exec()
.then(doc => res.status(200).json(doc))
.catch(err => res.status(400).json("Error: " + err));
The response is shown below, please note the usertask.date. it is NOT sorted
{
"_id": "5e...",
"name": "Run 100m",
"icon": "run",
"assignee": "Elon",
"userdata": [
{
"name": "Elon",
"date": "2020-03-21T20:02:38.143Z"
},
{
"name": "Bill",
"date": "2020-03-11T20:02:38.000Z"
},
{
"name": "Steve",
"date": "2020-03-19T20:02:38.000Z"
}
]
}
As you can see the it is not sorted by date - desc order. The result should be like shown below
"userdata": [
{
"name": "Elon",
"date": "2020-03-21T20:02:38.143Z"
},
{
"name": "Steve",
"date": "2020-03-19T20:02:38.000Z"
},
{
"name": "Bill",
"date": "2020-03-11T20:02:38.000Z"
}
]
$sort will use the last object which comes out from the aggregate pipe and theres no field "date" in this object:
{
$group: {
_id: "$matchedTask._id",
name: {$first: "$matchedTask.name"},
icon: {$first: "$matchedTask.icon"},
assignee: { $first: "$matchedTask.assignee" },
userdata: {
$push: {
name: "$matchedUser.name",
execDate: "$date"
}
}
}
},
your group has to returned a field named date in order to be able to sort it
{
$group: {
_id: "$matchedTask._id",
name: ....,
date: ....
}
}
{ $sort: {date: -1}}
if the value you want to sort is indide another object you must specify it on sort:
{$sort: {"userdata.date": -1}}
I fixed it, had to use sort two times, now I am able to get the result as I want
Solution provided below
UserTask.aggregate([
{
$lookup: {
from: "tasks",
localField: "task",
foreignField: "_id",
as: "matchedTask"
}
},
{
$unwind: "$matchedTask"
},
{
$lookup: {
from: "users",
localField: "user",
foreignField: "_id",
as: "matchedUser"
}
},
{
$unwind: "$matchedUser"
},
{
$sort: { date: -1 }
},
{
$group: {
_id: "$matchedTask._id",
name: { $first: "$matchedTask.name" },
icon: { $first: "$matchedTask.icon" },
assignee: { $first: "$matchedTask.assignee" },
userdata: {
$push: {
name: "$matchedUser.name",
execDate: "$date"
}
}
}
},
{
$sort: { _id: 1 }
}
])
.exec()
.then(doc => res.status(200).json(doc))
.catch(err => res.status(400).json("Error: " + err));

Joining two collections in mongodb

I have separate collections for 'comments','products' and 'users'. The 'comments' collection contains text, product_id and user_id. When a product is fetched I want the details of product along with details of the user in the result.
I have created schema using mongoose odm. I am using aggregate function to populate the product with comments using $lookup.
Product.aggregate([
{
$match:{
_id:mongoose.Types.ObjectId(id)
}
},
{
$lookup: {
from: "comments",
localField: "_id",
foreignField: "product",
as: "comments"
}
},
{
$match:{
"comments.product":mongoose.Types.ObjectId(id)
}
},
{
$lookup: {
from: "users",
localField: "comments.user._id",
foreignField: "user",
as: "comments.user"
}
}
])
expected result is
[
{
"_id": "5cc9441feed4c258881c99cd",
"title": "Batman",
"imageUrl": "images\\1556694047310_Batman.jpg",
"price": 555,
"description": "The dark knight",
"user": "5cbca36d4acc5d538c209014",
"__v": 2,
"comments": [
{
"_id": "5cc947125c69600d58c1be05",
"date": "2019-05-01T07:12:42.229Z",
"text": "This product is very nice",
"user":{
"_id": "5cbca36d4acc5d538c209014",
"name": "Clark Kent"
}
},
{
"_id": "5cc96eb4b2834d43f8a24470",
"date": "2019-05-01T09:46:34.774Z",
"text": "Anyone can be Batman",
"user":{
"_id": "5cbca5504acc5d538c209015",
"name": "Bruce Wayne"
},
}
}
]
actual result is
[
{
"_id": "5cc9441feed4c258881c99cd",
"title": "Batman",
"imageUrl": "images\\1556694047310_Batman.jpg",
"price": 555,
"description": "The dark knight",
"user": "5cbca36d4acc5d538c209014",
"__v": 2,
"comments": {
"user": [
{
"_id": "5cbca5504acc5d538c209015",
"name": "Bruce Wayne",
"email": "batman#gotham.com",
"password": "$2a$12$L.t/nBXq/xlic25Y0a884uGxjlimuNH/tcmWLg.sNkcjJ/C40Q14m",
"contactNumber": 9999999999,
"address": "Somewhere in Gotham",
"__v": 0
},
{
"_id": "5cbca7334acc5d538c209016",
"name": "Superman",
"email": "superman#metro.com",
"password": "$2a$12$mrogzC1Am86b0DnvTzosm.qfu38Ue7RqSNcnVSoCR55PtmLddeZv.",
"contactNumber": 9999999999,
"address": "Somewhere in metropolis",
"__v": 0
},
{
"_id": "5cbca7e54acc5d538c209017",
"name": "Wonder Woman",
"email": "ww#amazon.com",
"password": "$2a$12$Vt9XZUyOTULvel5zNAsMLeoMi3HlaGJJZN7OH2XkWuoAiZtDIGaMq",
"contactNumber": 9999999999,
"address": "Somewhere in Amazon",
"__v": 0
},
{
"_id": "5cbe192934ae2944c8704a5a",
"name": "Barry Allen",
"email": "barry#flash.com",
"password": "$2a$12$k73Wp1HTMv/MhUV3BOok3OSh.nnLq3vWG1Qz9ZTO7iB7saFlxhLjW",
"contactNumber": 9999999999,
"address": "Somewhere in Central City",
"__v": 0
}
]
}
}
]
Your $lookup query of users is overwriting the comments array. Its not working as you think it'll.
You need to unwind the comments array and then run that $lookup of users and then group by the products.
Edit: I have updated the query with $group by code too. Also you can playa around with the query here:
https://mongoplayground.net/p/2EA-Glz8Hrm
Product.aggregate([
{
$match: {
_id: "5cc9441feed4c258881c99cd"
}
},
{
$lookup: {
from: "comments",
localField: "_id",
foreignField: "product",
as: "comments"
}
},
{
$unwind: "$comments"
},
{
$lookup: {
from: "users",
localField: "comments.user",
foreignField: "_id",
as: "comments.user"
}
},
{
$unwind: "$comments.user"
},
{
$group: {
_id: "$_id",
// add other fields you want to include
comments: {
$addToSet: "$comments"
}
}
},
])
As suggested by Hamza, I made following changes to my query
Product.aggregate([
{
$match: {
_id: mongoose.Types.ObjectId(id)
}
},
{
$lookup: {
from: "comments",
localField: "_id", //field from input document
foreignField: "product", // field from documents of the 'from' collection
as: "comments"
}
},
{
$unwind: "$comments"
},
{
$lookup: {
from: "users",
localField: "comments.user", //field from input document
foreignField: "_id", // field from documents of the 'from' collection
as: "comments.user"
}
},
{
$unwind: "$comments.user"
},
{
$group: {
_id: "$_id",
title: { $first: "$title" }, // $first returns the first expression of the document it encounters, ex. first title
price: { $first: "$price" },
imageUrl: { $first: "$imageUrl" },
description: { $first: "$description" },
rating: { $first: "$rating" },
comments: {
$addToSet: "$comments" // group comments and create an array
}
}
},
{
$project: {
_id: 1,
title: 1,
price: 1,
imageUrl: 1,
description: 1,
rating: 1,
comments: {
_id: 1,
text: 1,
date: 1,
user: {
_id: 1,
name: 1
}
}
}
}
])
With this I got the desired result.

How to use $lookup on embedded document field in mogodb

Please have a look, your help will be appriciated
var user = new Schema({
name: String,
});
var Comments = new Schema({
title : String
, body : String
,user_id : {type: Schema.Types.ObjectId, ref: 'user' }
, date : Date
});
var blog = new Schema({
author : String
, title : String
, body : String
, date : Date
, user_id :{type: Schema.Types.ObjectId, ref: 'user' }
, comments : [Comments]
});
db.blogs.aggregate([
{ $match : { "_id" : ObjectId("57e3b7f4409d80a508d52769") } },
{ $lookup: {from: "users", localField: "user_id", foreignField: "_id", as: "User"} },
])
this returns
[
{
"_id": "57e3b7f4409d80a508d52769",
"author": "Tariq",
"title": "MyfirstPost",
"body": "This is my first post",
"user_id": "57e3b763f7bc810c08f9467a",
"comments": [
{
"title": "hi",
"body": "again i am commenting on this",
"user_id": "57e3b763f7bc810c08f9467a",
"_id": "57e3c153409d80a508d5276b"
},
{
"title": "hi",
"body": "this is seond comment",
"user_id": "57e3b763f7bc810c08f9467a",
"_id": "57e3c8632ebca0ee0afb2ac6"
}
],
"__v": 0,
"User": [
{
"_id": "57e3b763f7bc810c08f9467a",
"name": "Tariq",
"username": "teekay",
"password": "123456",
"__v": 0
}
]
}
]
this return result by comparing blog table is and user table _id which is fine .. but I want to get userdetail with each comment by using user_id of “comments.user_id” blog collection and “_id” of collection
should be something like this
"_id": "57e3b7f4409d80a508d52769",
"author": "Tariq",
"title": "MyfirstPost",
"body": "This is my first post",
"user_id": "57e3b763f7bc810c08f9467a",
"comments": [
{
"title": "hi",
"body": "again i am commenting on this",
"user_id": "57e3b763f7bc810c08f9467a",
"_id": "57e3c153409d80a508d5276b",
"User": [
{
"_id": "57e3b763f7bc810c08f9467a",
"name": "Tariq",
"username": "teekay",
"password": "123456",
"__v": 0
}
]
},
You can run an aggregation operation of the pipeline:
db.blogs.aggregate([
{ "$unwind": "$comments" },
{
"$lookup": {
"from": "users",
"localField": "comments.user_id",
"foreignField": "_id",
"as": "comments.user"
}
},
{ "$unwind": "$comments.user" },
{
"$group": {
"_id": "$_id",
"author": { "$first": "$author" },
"title": { "$first": "$title" },
"body": { "$first": "$body" },
"comments": { "$push": "$comments" },
"user_id": { "$first": "$user_id" }
}
},
{
"$lookup": {
"from": "users",
"localField": "user_id",
"foreignField": "_id",
"as": "user"
}
},
{ "$unwind": "$user" },
])

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