I have this schema
const GroupSchema = new Schema({
id: { type: String },
users: [{ type: Number }],
status: { type: Boolean }
},
{
timestamps: true
});
I try to aggregate distinct users value sorted by created date.
Example
{
"users": [1111, 2222],
"createdAt": {
"$date": "2020-09-30T10:51:33.058Z"
}
}
{
"users": [1111, 2222],
"createdAt": {
"$date": "2020-09-29T10:51:33.058Z"
}
}
I try with :
Group.aggregate([
{ "$sort": { "createdAt": -1 } },
{ $group : { _id : "$users" }}, //, created : { $last : "created" }
{ $match : { users : {$in : [1111] } }}
])
I expect
{
"users": [1111, 2222],
"createdAt": {
"$date": "2020-09-30T10:51:33.058Z"
}
}
how can i solve?
Thanks.
You can try,
$match your condition
$sort by createdAt date
$group by users array and get latest document in latestDoc
$replaceWith to replace latestDoc in root
db.collection.aggregate([
{ $match: { users: { $in: [1111] } } },
{ $sort: { createdAt: -1 } },
{
$group: {
_id: "$users",
latestDoc: { $first: "$$ROOT" }
}
},
{ $replaceWith: "$latestDoc" }
])
Playground
Related
I want to get all objects in a radius and also for each single of those objects their average rating and total ratings. I've got both queries working but I'm looking to combine these 2 into one.
LocationSchema
const LocationObject = new Schema({
name: String
location: {
type: {
type: String,
enum: ['Point'],
default: 'Point',
required: true
},
coordinates: {
type: [Number],
required: true
}
}
})
ratingSchema
const Rating = new Schema({
locationObject: { type: Schema.Types.ObjectId, ref: 'LocationObject' },
average: Number,
})
locationQuery
const objects = await LocationObject.find({
location: {
$geoWithin: {
$centerSphere: [[lon, lat, radius]
}
}
})
RatingAggregation for single LocationObject
const result = await Rating.aggregate([
{
"$match": {
"locationObject": objectID
}
},
{
"$facet": {
"numbers": [
{
"$group": {
"_id": null,
"totalRating": {
"$sum": "$average"
},
"totalItemCount": {
"$sum": 1.0
}
}
}
],
}
},
{
"$unwind": "$numbers"
},
{
"$project": {
"_id": null,
"avgRating": {"$divide": ["$numbers.totalRating", "$numbers.totalItemCount"]},
"totalRatings": "$numbers.totalItemCount"
}
}
])
The final result should return an array with locationObjects which each has an average and totalRatings added.
mongo playground: https://mongoplayground.net/p/JGuJtB5bZV4
Expected result
[
{
name: String,
location: {
coordinates: [Number, Number],
},
avgRating: Number,
totalRatings: Number
},
{
name: String,
location: {
coordinates: [Number, Number],
}
}
]
As per your latest playground, you could achieve using this
db.locationObject.aggregate([
{
"$match": {
"location": {
"$geoWithin": {
"$centerSphere": [
[
6.064953,
52.531348
],
0.0012
]
}
}
}
},
{
"$lookup": { //You need to bring both the collection data together
"from": "Rating",
"localField": "_id",
"foreignField": "locationObject",
"as": "locRatings"
}
},
{
$unwind: "$locRatings"
},
{
"$group": { //you can simplify the other pipelines
"_id": "$_id",
"field": {
"$avg": "$locRatings.average"
},
"totalItemCount": {
"$sum": 1.0
}
}
}
])
To preserve the document fields, you need to use accumulators as in this playground
{
"$group": {
"_id": "$_id",
"field": {
"$avg": "$locRatings.average"
},
"totalItemCount": {
"$sum": 1.0
},
"locations": {
"$addToSet": "$location"
}
}
}
you can keep empty/null arrays in unwind stage as below
playground
{
$unwind: {
"path": "$locRatings",
"preserveNullAndEmptyArrays": true
}
},
You can add a project stage to ignore null values if needed.
I have made several efforts to select a single specific document that contains the minimum value from the database.
let Lowestdate = await BTCMongo.aggregate(
[
// { "$sort": { "name": 1,
{
$match : { "createdAt" : { $gte: new Date(last),$lte: new Date(NEW) } } },
{
$group:
{
_id:null,
minFee_doc:{$min: "$$ROOT"},
minFee: { $min:{$toDouble:"$one"}},
firstFee: { $first: "$one" },
lastFee: { $last: "$one" },
maxFee: { $max: {$toDouble:"$one"}},
}
},
]
).then(result => {}):
with minFee_doc:{$min: "$$ROOT"}, I have been trying to return the document containing the minimum $min but it keeps returning document containing $first
How do i select the document with minimum value?
Note : i will like to return the whole document including the "CreatedAt" "UpdatedAt", and _id. of the document containing the minimum value
Expected Result should look like:
{
"minFee_doc": {
"_id": "61e84c9f622642463640e05c",
"createdAt": "2022-01-19T17:38:39.034Z",
"updatedAt": "2022-04-24T14:48:38.100Z",
"__v": 0,
"one": 2
},
"minFee": 2,
"firstFee": 3,
"lastFee": 5,
"maxFee": 6
}
Edit: also to provide a single document not multiple
$push all docs in $group then $set the array with $filter
db.collection.aggregate([
{
$match: {}
},
{
$group: {
_id: null,
minFee_doc: { $push: "$$ROOT" },
minFee: { $min: { $toDouble: "$one" } },
firstFee: { $first: "$one" },
lastFee: { $last: "$one" },
maxFee: { $max: { $toDouble: "$one" } }
}
},
{
$set: {
minFee_doc: {
$filter: {
input: "$minFee_doc",
as: "m",
cond: { "$eq": [ "$$m.one", "$minFee" ] }
}
}
}
}
])
mongoplayground
I am trying to find the latest "order" in "orders" array in the whole collection (Not only in the one object).
Data:
[
{
_id: 1,
orders: [
{
title: 'Burger',
date: {
$date: '2021-07-18T13:12:08.717Z',
},
},
],
},
{
_id: 2,
orders: [
{
title: 'Salad',
date: {
$date: '2021-07-18T13:35:01.586Z',
},
},
],
},
];
Code:
var restaurant = await Restaurant.findOne({
'orders.date': 1,
});
Rather simple:
db.collection.aggregate([
{ $project: { latest_order: { $max: "$orders.date" } } }
])
If you like to get the full order use this:
db.collection.aggregate([
{
$project: {
latest_order: {
$first: {
$filter: {
input: "$orders",
cond: { $eq: [ "$$this.date", { $max: "$orders.date" } ] }
}
}
}
}
},
{ $sort: { "latest_order.date": 1 } },
{ $limit: 1 }
])
Mongo Playground
You have to use aggregation for that
db.collection.aggregate([
{ $unwind: "$orders" },
{ $sort: { "orders.date": -1 } },
{ $limit: 1 },
{
"$group": {
"_id": "$_id",
"orders": { "$first": "$orders" }
}
}
])
Working Mongo playground
Please i am new to node js and MongoDB.
When i want to retrieve a post by id, i want to be able to retrieve the previous post and next post also.
this is my post, it only retrieves the current post by id.
Post.findById(req.params.postId)
.then((existingpost) => {
console.log(Post.find(req.params.postId))
if (existingpost) {
res.send(existingpost);
}
return res.status(404).send({
message: "Post does not exist with id " + req.params.postId,
});
})
.catch((err) => {
if (err.kind === "ObjectId") {
return res.status(404).send({
message: "Post does not exist with id " + req.params.postId,
});
}
return res.status(500).send({
message:
"Some error occurred while retrieving the post with postId " +
req.params.postId,
});
});
};
I currently receive the object with the id like this which is fine.
{
"_id": "6009f3e294d8a033402a76e7",
"title": "Covid 19 in Italy",
"author": "John Doe",
"createdAt": "2021-01-21T21:36:34.514Z",
"updatedAt": "2021-01-21T21:36:34.514Z",
"__v": 0
}
But i will love to receive the object of the current id, the previous object and the next object.
something like this.
[{
"_id": "3230g5e382d8a033402a76e7",
"title": "Effect of Covid on the Economy",
"author": "John Doe",
"createdAt": "2021-01-21T21:36:34.514Z",
"updatedAt": "2021-01-21T21:36:34.514Z",
"__v": 0
},
{
"_id": "6009f3e294d8a033402a76e7",
"title": "Covid 19 in Italy",
"author": "John Doe",
"createdAt": "2021-01-21T21:36:34.514Z",
"updatedAt": "2021-01-21T21:36:34.514Z",
"__v": 0
},
{
"_id": "4567hye294d8a033402a76e7",
"title": "Life after Covid",
"author": "John Doe",
"createdAt": "2021-01-21T21:36:34.514Z",
"updatedAt": "2021-01-21T21:36:34.514Z",
"__v": 0
}]
Since its a UUID, this approach might help you..
$sort to sort the documents by asc
$group and $unwind to get the index
$facet to categorize the incoming data into current and allDocs
We know current is only one object, so we do $unwind to deconstruct the array
We already know the index, so we use $filter to get prev, current and next using index
$unwind to deconstruct the array
$replaceRoot to make the objects to the root
Here is the script
db.collection.aggregate([
$sort: { createdAt: 1 } },
{
$group: {
_id: null,
data: { $push: "$$ROOT"}
}
},
{ $unwind: { path: "$data", includeArrayIndex: "index" } },
{
$facet: {
current: [
{ $match: { "data._id": "3230g5e382d8a033402a76e7" } }
],
allDocs: [
{ $match: {} }
]
}
},
{
$unwind: "$current"
},
{
$project: {
docs: {
$filter: {
input: "$allDocs",
cond: {
$or: [
{ $eq: [ "$$this.index", { $subtract: [ "$current.index", 1 ] } ] },
{ $eq: [ "$$this.index", "$current.index" ] },
{ $eq: [ "$$this.index", { $add: [ "$current.index", 1 ] } ] }
]
}
}
}
}
},
{ "$unwind": "$docs" },
{ "$replaceRoot": { "newRoot": "$docs.data" } }
])
Working Mongo playground
There are many ways to do this, this is one of the way. If you feel you have a lot of document, then try to avoid $unwind which is expensive, in that case you can try using createdDate instead of index
I am not sure is there any straight way to do this, you can try aggregation,
Using UUID and CreatedAt:
$facet to get all documents in all after sorting in ascending order by createdAt
$let to define vars states with start and total documents,
$cond check condition if index of input uuid is zero then return start: 0 and total: 2 documents we have to slice from all array, else get current index and subtract minus 1 and total: 3
in to return slice documents on the base of start and total
Post.aggregate([
{ $facet: { all: [{ $sort: { createdAt: 1 } }] } },
{
$project: {
result: {
$let: {
vars: {
states: {
$cond: [
{ $eq: [{ $indexOfArray: ["$all._id", req.params.postId] }, 0] },
{ start: 0, total: 2 },
{
start: {
$subtract: [{ $indexOfArray: ["$all._id", req.params.postId] }, 1]
},
total: 3
}
]
}
},
in: { $slice: ["$all", "$$states.start", "$$states.total"] }
}
}
}
}
])
Playground
Using ObjectID:
convert your string input id req.params.postId to object id using mongoose.Types.ObjectId
$facet to separate result,
first, $match to get current and next documents, $sort _id in descending order, $limit 2
second, $match to get previous document, $sort _id in descending order, $limit 1
$project to get result after concat both array first and second using $concatArrays
req.params.postId = mongoose.Types.ObjectId(req.params.postId);
Post.aggregate([
{
$facet: {
first: [
{ $match: { _id: { $gte: req.params.postId } } },
{ $sort: { _id: 1 } },
{ $limit: 2 }
],
second: [
{ $match: { _id: { $lt: req.params.postId } } },
{ $sort: { _id: -1 } },
{ $limit: 1 }
]
}
},
{ $project: { result: { $concatArrays: ["$first", "$second"] } } }
])
Playground
I want to group my data based on event date with pagination. However what i am getting is whole record totalcount instead of eventDate count. because of this UI part is not working properly. Here is my collection sample:
{
"_id" : ObjectId("5fc4d0009a25e8cfbe306381"),
"eventDate" : ISODate("2021-11-29T01:00:00.000Z"),
"team1" : {
"tName" : "Chicago Bears",
},
"team2" : {
"tName" : "Green Bay Packers",
}
}
{
"_id" : ObjectId("5fc4d0019a25e8cfbe3063ff"),
"eventDate" : ISODate("2021-11-30T01:00:00.000Z"),
"team1" : {
"tName" : "Nashville SC",
},
"team2" : {
"tName" : "Columbus Crew",
}
}
{
"_id" : ObjectId("5fc4d0019a25e8cfbe3063f4"),
"eventDate" : ISODate("2021-11-30T01:00:00.000Z"),
"team1" : {
"tName" : "yyyy",
},
"team2" : {
"tName" : "xxxx",
}
}
here is my query:
db.getCollection('game').aggregate([
{ $addFields: { "newEventDate": {$dateToString:{ format: "%Y-%m-%d", date: "$eventDate" }}}},
{ "$match": {
"eventDate": { $gte: new Date() }
}
},
{ "$facet": {
"resultData": [
{ "$match": {
"eventDate": { $gte: new Date() }
}
},
{ "$group": {
"_id": "$newEventDate",
"games": {$push: {
team1:"$team1",
team2:"$team2"
}}
}
},
{ $sort: {eventDate: 1} },
{
$limit: 1
}
],
"pageInfo": [
{ "$count": "totalRecords" }
]}
}
]);
After executing this query this is my response:
{
"resultData" : [
{
"_id" : "2021-11-29",
"games" : [
{
"awayTeam" : {
"tName" : "Chicago Bears"
},
"homeTeam" : {
"tName" : "Green Bay Packers"
}
},
]
}
],
"pageInfo" : [
{
"totalRecords" : 3 **[here i want 2 ie total event date]**
}
]
}
$match your condition
move your $group stage outside from $facet, convert your date from string inside group, add you date in group stage because we are going to sort in next stage
$sort by eventDate ascending order
$facet, first get single record using $limit, and second part get total count of the record using $count
db.collection.aggregate([
{ $match: { eventDate: { $gte: new Date() } } },
{
$group: {
_id: {
$dateToString: {
format: "%Y-%m-%d",
date: "$eventDate"
}
},
eventDate: { $first: "$eventDate" },
games: {
$push: {
team1: "$team1",
team2: "$team2"
}
}
}
},
{ $sort: { eventDate: 1 } },
{
$facet: {
resultData: [{ $limit: 1 }],
pageInfo: [{ $count: "totalRecords" }]
}
}
])
Playground