count documents with multiple conditions in one query - node.js

I am trying to count database records in mongoDB (using mongoose) where records have a status of pending and approved as well as rejected. So, I am basically trying to get a result where I can show a count of each and display it in my view ie:
Pending: 35
Approved: 97
Rejected: 12
I have this but it only counts 'pending'. Is there a way to count all 3 in one query or do I need to run 3 separate queries and get a result for each of them?
Product.countDocuments({status: 'pending', userId: req.session.user._id})
.then(pending => {
if (!pending) {
return next();
}
req.pending = pending;
next();
})
.catch(err => {
console.log(err);
});
EDIT: I have managed to do it like this to a certain extent, well in console I am getting a count of all of the results back but just need to figure out how to get each one into it's own variable.
Product.aggregate([
{ $group: { _id: { status: "$status"}, totalStatus: {$sum: 1} } }
])
.then(function (res) {
console.log(res);
next();
});

For finding multiple count in single query,Please use mongodb aggregation framework it manipulate data in multiple stages, your question is already answered, please visit below link.I update the query for you.
Multiple Counts with single query in mongodb
Product.aggregate([
{ "$facet": {
"Pending": [
{ "$match" : { "status": { "$exists": true, "$in":["pending"] }}},
{ "$count": "Pending" },
],
"Approved": [
{ "$match" : {"status": { "$exists": true, "$in": ["approved"] }}},
{ "$count": "Approved" }
],
"Rejected": [
{ "$match" : {"status": { "$exists": true, "$in": ["rejected"] }}},
{ "$count": "Rejected" }
]
}},
{ "$project": {
"Pending": { "$arrayElemAt": ["$Pending.Pending", 0] },
"Approved": { "$arrayElemAt": ["$Approved.Approved", 0] },
"Rejected": { "$arrayElemAt": ["$Rejected.Rejected", 0] }
}}
])

Related

Remove Embedded Documents in an Array in MongoDB with mongoose (updateOne - $pull) not work

I have an app with MongoDB (Mongoose) in NodeJs.
In a collection I have this type of documents, defined by weeks:
{
"_id":
{"$oid":"617f3f51f883fab2de3e7260"},
"endDate":{"$date":"2021-11-07T23:59:59.000Z"},
"startDate":{"$date":"2021-11-01T00:00:00.000Z"},
"wastes":[
{"timestamp":{"$date":"2021-11-01T01:00:58.000Z"},"duration":780},
{"timestamp":{"$date":"2021-11-01T01:00:58.000Z"},"duration":1140},
{"timestamp":{"$date":"2021-11-01T03:00:58.000Z"},"duration":540},
{"timestamp":{"$date":"2021-11-01T07:00:58.000Z"},"duration":540},
{"timestamp":{"$date":"2021-11-01T09:00:58.000Z"},"duration":960},
{"timestamp":{"$date":"2021-11-01T09:00:58.000Z"},"duration":1140},
{"timestamp":{"$date":"2021-11-01T15:00:58.000Z"},"duration":180},
{"timestamp":{"$date":"2021-11-01T15:00:58.000Z"},"duration":540}
...
]}
I have a function that finds wastes with the same timestamp, for example "2021-11-01T01:00:58.000Z", gives the longest duration for this timestamp.
I want to delete all entries with that timestamp:
{"timestamp":{"$date":"2021-11-01T01:00:58.000Z"},"duration":780},
{"timestamp":{"$date":"2021-11-01T01:00:58.000Z"},"duration":1140}
And insert only the one with the highest duration:
{"timestamp":{"$date":"2021-11-01T01:00:58.000Z"},"duration":1140}
I'm using updateOne with $pull and $push, but it doesn't work.
let query = {
startDate: new Date(startDayWeek),
};
let deleteProjection = {
$pull: {
wastes: { timestamp: new Date(timestampDeleteInsertion) },
},
};
let insertProjection = {
$push: { wastes: insertRegisterForTimestamp },
};
//Delete
await coleccion.updateOne(query, deleteProjection);
//Insertion
await coleccion.updateOne(query, insertProjection);
I have also tried with {upsert: false}, {multi: true}.
If I use the same commands in the MongoDB Compass shell, it works without problems:
//Delete
db.coleccion.updateOne({startDate: ISODate('2021-11-01T00:00:00')}, {$pull: {'wastes': {timestamp: ISODate('2021-11-01T01:00:58.000Z')}}})
//Insertion
db.coleccion.updateOne({startDate: ISODate('2021-11-01T00:00:00')}, {$push: {'wastes': {'timestamp':ISODate('2021-11-01T01:00:58.000Z'), 'duration': 1140}}})
You can achieve expected behaviour with Updates with Aggregation Pipeline
The aggregation will consists of 3 steps:
find out the max duration using $reduce; stored the result into a field
$filter the wastes array by keeping only elements not equal to the selected timestamp or the duration is not the max duration
$unset the helper field created in step 1
db.collection.update({},
[
{
$addFields: {
maxDuration: {
"$reduce": {
"input": "$wastes",
"initialValue": null,
"in": {
"$cond": {
"if": {
$and: [
{
$eq: [
"$$this.timestamp",
{
"$date": "2021-11-01T01:00:58.000Z"
}
]
},
{
$gt: [
"$$this.duration",
"$$value"
]
}
]
},
"then": "$$this.duration",
"else": "$$value"
}
}
}
}
}
},
{
$set: {
wastes: {
$filter: {
input: "$wastes",
as: "w",
cond: {
$or: [
{
$ne: [
"$$w.timestamp",
{
"$date": "2021-11-01T01:00:58.000Z"
}
]
},
{
$eq: [
"$$w.duration",
"$maxDuration"
]
}
]
}
}
}
}
},
{
"$unset": "maxDuration"
}
])
Here is the Mongo playground for your reference.
I have the same issue with the updateOne and pull command, if use the updateOne with push, it works.
In the mongo shell or in the compass, both situations (push/pull) works, but with mongoose, it finds the criteria but don't update/modify.
Result
{
"acknowledged" : true,
"matchedCount" : 1.0,
"modifiedCount" : 0.0
}

Fetch grouped items from database

I'm trying to group values together in mongoose. I have a "Review" schema with the following fields:
{ userId, rating, comment }
There are many documents with the same userId. How can I retrieve them in the following format:
{userId: [...allRatings]
Or even better, is there a way to retrieve the averages for each userId? so like this: {userId: 2.8}
I know it's possible and very simple to do in node.js, but is there a way of doing it with mongoose?
Mongoose is really just a vehicle to pass commands to your mondoDB server, so accomplishing what you want in mongoose isn't dissimilar to accomplishing it in the mongo shell.
Here is the aggregation you're looking for:
db.collection.aggregate([
{
"$group": {
"_id": "$userId",
"ratings": {
$push: "$rating"
}
}
},
{
"$project": {
"_id": false,
"userId": "$_id",
"avgRating": {
"$avg": "$ratings"
}
}
}
])
The first stage of the pipeline groups all ratings by useId. The second stage calculates the ratings average and pretties up the key display. That's it. The result will be this:
[
{
"avgRating": 2.8,
"userId": 110
},
{
"avgRating": 3.275,
"userId": 100
}
]
Here is a playground for you: https://mongoplayground.net/p/yXVxk4klabB
As for how to specifically run this command in mongoose, well that's pretty straightforward:
const YourModel = mongoose.model('your_model');
...
YourModel.aggregate([
{
"$group": {
"_id": "$userId",
"ratings": {
$push: "$rating"
}
}
},
{
"$project": {
"_id": false,
"userId": "$_id",
"avgRating": {
"$avg": "$ratings"
}
}
}
])
.then(result => {
console.log(result);
})

I will like to return the previous object and the next object of a matching object id in node

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

Query to get latest three users, sort by date - Mongoose Node.js

This is the data from Mongodb
(Task.json)
{
"username": "john",
"taskId": "001",
"date": "2020-02-18T20:14:19.000Z",
},
{
"username": "david",
"taskId": "001",
"date": "2020-02-18T21:48:19.000Z",
},
{
"username": "john",
"taskId": "002",
"date": "2020-02-15T20:20:32.000Z",
}
... many more
What I am trying to acheive
I am trying a write a query that returns taskId with a list of the
latest users who executed the task (sorted by date - descending).
I only want the last three users who executed the task to show up on the list, thus the user array should not contain more the 3 users per task
Here is an example I created of how I want the response to be:
{
"tasks": [
{
"taskid": "001",
"users": [
{
"username": "david",
"date": "2020-02-18T21:48:19.000Z"
},
{
"username": "john",
"date": "2020-02-18T20:14:19.000Z"
}
]
},
{
"taskid": "002",
"users": [
{
"username": "john",
"date": "2020-02-15T20:20:32.000Z"
}
]
}
]
}
My progress so far:
router.route("/latest-tasks").get((req, res) => {
Task.find()
.sort({ date: "desc" })
.then(doc =>
res.status(200).json({
taskId: doc.taskId,
list: doc.map(doc => {
return {
username: doc.username,
date: doc.date
};
})
})
)
.catch(err => res.status(400).json("Error: " + err));
});
A bit of multi-query scenario here, I suggest you use MongoDB aggregation to do this. This query should work:
Todo.aggregate([
{
$sort: { taskId: 1, date: 1 }
},
{
$group: {
_id: "$taskId",
users: {
$push: { username: "$username", date: "$date" }
}
}
},
{
$project: {
_id: 0,
taskid: "$_id",
users: {
$filter: {
input: [
{ $arrayElemAt: ["$users", 0] },
{ $arrayElemAt: ["$users", 1] },
{ $arrayElemAt: ["$users", 2] }
],
as: "user",
cond: { $ne: ["$$user", null] }
}
},
}
}
]).exec()
.then(doc => { console.log(doc); })
.catch(err => { console.log(err); });
Aggregation Pipeline Explanation:
$sort: This sorts the tasks using the taskId and date field in an ascending order
$group: This group the tasks by taskId. This is how we get all users associated with a task
$project: This helps extract just the first 3 users associated with a task. The $filter operator used inside this pipeline stage helps to remove null values in case a task does not have up to three users associated with it.
Links: Aggregation Pipeline, Pipeline Stages, Pipeline Operators
You need to use .aggregate:
Mongoose code not tested
Task.aggregate([
{
$sort: {
taskId: 1,
date: -1
}
},
{
$group: {
_id: "$taskId",
users: {
$push: {
username: "$username",
date: "$date"
}
}
}
},
{
$facet: {
tasks: [
{
$sort: {
_id: 1
}
},
{
$project: {
_id: 0,
taskid: "$_id",
users: 1
}
}
]
}
}
]).exec()
.then( doc => res.status(200).json(doc))
.catch(err => res.status(400).json("Error: " + err));
MongoPlayground

Node.js calling MongoDB with aggregate find

I have used SQL Server for a long time and just really learning MongoDB. I am trying to figure out how to do the aggregate finds to get just the data I want. Here is a sample from the database:
{
"_id": "1",
"user_id": "123-88",
"department_id": "1",
"type": "start",
"time": "2017-04-20T19:40:15.329Z"
}
{
"_id": "2",
"user_id": "123-88",
"department_id": "1",
"type": "stop",
"time": "2017-04-20T19:47:15.329Z"
}
What I want to do is find each unique user_id of department 1, only take the record with the latest time and tell me if they are oncall or not. So in the example above user 123-88 is not oncall now. How would you make this query? I know you will need something like this:
TimeCard.aggregate([
{ $match: {department_id: req.query.department_id}},
{ $sort: { user_id: 1, time: 1 }},
{ $group: { _id: "$user_id", current_type: "$type", lastTime: { $last: "$time" }}}
], function(err, docs){
if(err){console.log(err);}
else {res.json(docs);}
});
But I keep erroring so I know I am not correct in my logic. I know if I just have the match it works and if I add the sort it matches and sorts but the final group is not working. Also what would I add to then only show the people that are oncall. Thanks again for your help.
You can count how many "types" per user_id you have, this can be done by $sum, if it's odd, the user is oncall, because there is a start without a stop. This approach is correct only if you always have a stop for a start.
TimeCard.aggregate([
{ $match: { department_id: req.query.department_id } },
{ $sort: { user_id: 1, time: 1 } },
{ $group: { _id: "$user_id", count_types: { $sum: 1 }, lastTime: { $last: "$time" }}},
{ $match: { count_types: { $mod: [ 2, 1 ] } } },
], function(err, docs) {
if(err) { console.log(err); }
else { res.json(docs); }
});

Resources