mongo $in on multiple fields - node.js

I'm trying to get data with $in operator on multiple cases,
here below is my sample data
[{
"userId":1,
"attemptNum":2,
"submissionCount":1,
"questionId":1
},
{
"userId":1,
"attemptNum":2,
"submissionCount":2,
"questionId":1
},
{
"userId":1,
"attemptNum":2,
"submissionCount":1,
"questionId":2
}]
and here below is my query
let history = await this.dbCollection.
.find({
$and: [
{ userId: 1 },
{ attemptNum: 2 },
{ questionId: { $in: [1, 2] } },
{ submissionCount: { $in: [2, 1] } },
],
})
.lean();
expected output:
[{
"userId":1,
"attemptNum":2,
"submissionCount":2,
"questionId":1
},
{
"userId":1,
"attemptNum":2,
"submissionCount":1,
"questionId":2
}]
One thing i got to know that $in works as $or by this SO question,
for temporary solution i written map and getting the desired output
here below is sample code of map
codingHistory.map((mongoHistory) =>{
submittedQuestionIds.map((postgresData) =>{
if(postgresData.submissionCount == mongoHistory.submissionCount && postgresData.questionId == mongoHistory.questionId){
filteredData.push(mongoHistory)
}
})
})
so my question is how can I make this work with a mongo query without external loops
any help or suggestions are really so helpful.

Related

Update nested object in array MongoDB

I need to find and update documents with category that corresponding to the query. Array could contain mo than one corresponding id.
Query:
{
"ids": ["61f1cda47018c60012b3dd01", "61f1cdb87018c60012b3dd07"],
"userId": "61eab3e57018c60012b3db3f"
}
I got collection with documents like:
`{
"_id":{"$oid":"61f1cdd07018c60012b3dd09"},
"expenses":[
{"category":"61eafc104b88e154caa58616","price":"1111.00"},
{"category":"61f1cdb87018c60012b3dd07","price":"2222.00"},
{"category":"61f1cda47018c60012b3dd01","price":"1241.00"},
{"category":"61f1cdb87018c60012b3dd07","price":"111.00"}
],
"userId":"61eab3e57018c60012b3db3f"
}`
my method:
async myMethod(ids: [string], userId: string) {
try {
const { ok } = await this.ExpensesModel.updateMany(
{"userId": userId, "expenses.category": { $in: ids }},
{$set: {"expenses.$.category": "newCategoryID"}}
);
return ok
} ........
I path array of ids ["61f1cda47018c60012b3dd01","61f1cdb87018c60012b3dd07","61f1cdb87018c60012b3dd07"] and userId, this code update only 1 category by document.
So can i made it with mongo build in methods? or i need to find matching document and update it it by my self and after that update or insert;
Update with arrayFilters
db.collection.update({
"expenses.category": {
$in: [
"61f1cda47018c60012b3dd01",
"61f1cdb87018c60012b3dd07"
]
}
},
{
$set: {
"expenses.$[elem].category": "61eab3e57018c60012b3db3f"
}
},
{
arrayFilters: [
{
"elem.category": {
$in: [
"61f1cda47018c60012b3dd01",
"61f1cdb87018c60012b3dd07"
]
}
}
]
})
mongoplayground

Push to array in Mongodb

How do I push to the inner arrays in MongoDB?
[
{ emoji1: ['user19', 'user20', 'user21']},
{ emoji5: ['user12', 'user13', 'user14']},
{ emoji9: ['user29', 'user30', 'user34']}
]
I tried:
await Post
.updateOne({ _id: postID }, {
$push: {
[`reactions[0].emoji1`]: 'random user'
}
})
...where Post is my Mongoose Schema and "reactions" is the array above. I think I am doing something wrong in $push.
The result should be:
[
{ emoji1: ['user19', 'user20', 'user21', 'random user']},
{ emoji5: ['user12', 'user13', 'user14']},
{ emoji9: ['user29', 'user30', 'user34']}
]
You can use this query:
db.collection.update({
id: 1,
"reactions.emoji1": {
"$exists": true
}
},
{
"$push": {
"reactions.$.emoji1": "random user"
}
})
Example here

check an array of string value with array of object in mongodb

I have array of strings like this
let fromHour = ['2.5','3','3.5']
let toHour = ['2.5','3','3.5']
I have an array of object saved in mongoDB
timeRange = [
{
from:'2.5',
to:'3'
},
{
from:'3',
to:'3.5'
}
]
I want to check if any of my array of string value exist in that object value
I have tried this but it give me this error ( Unrecognized expression '$match' )
checkAppoint = await Appointment.aggregate([
{
$project: {
date: myScheduleFinal[k].date,
status: { $in: ['pending', 'on-going'] },
timeRange: {
'$match': {
'from': { $in: fromHolder },
'to': { $in: toHolder },
},
},
},
},
]);
also I have tried this solution and it work for me but it take to much time so I am trying this with aggregate
checkAppoint = await Appointment.findOne({
date: myScheduleFinal[k].date,
status: { $in: ['pending', 'on-going'] },
timeRange:{$elemMatch:{
from:{$in:fromHolder},
to:{$in:toHolder}
}}
});
So anyone have a solution for that
Just try $elemMatch and $in operators,
using find() method
checkAppoint = await Appointment.find({
timeRange: {
$elemMatch: {
from: { $in: fromHour },
to: { $in: toHour }
}
}
})
Playground
using aggregate() method
checkAppoint = await Appointment.aggregate([
{
$match: {
timeRange: {
$elemMatch: {
from: { $in: fromHour },
to: { $in: toHour }
}
}
}
}
])
Playground
So I have found a way around to solve this problem and I will share the solution I used
First I want to minimize my request to mongodb so I am now making just one request that bring all the appointment with the required date
and I want to make it this way because my fromHour and toHour array will change many time through single request
helperArray => contains all the day I want to check it's range
let checkAppoint = await Appointment.find({
date: { $in: helperArray },
status: { $in: ['pending', 'on-going'] },
});
now inside my for loop I will go through that data
checkAppoint.filter((singleAppoint) => {
if (singleAppoint._doc.date === myScheduleFinal[k].date) {
singleAppoint._doc.timeRange.map((singleTime) => {
if (fromHolder.includes(singleTime.from)) {
busy = true;
}
});
}
});

How to pass an optional argument in Mongoose/MongoDb

I have the following query:
Documents.find({
$and: [
{
user_id: {$nin:
myUserId
}
},
{ date: { $gte: dateMax, $lt: dateMin } },
{documentTags: {$all: tags}}
],
})
What I'm trying to do is make the documentTags portion of the query optional. I have tried building the query as follows:
let tags = " ";
if (req.body.tags) {
tags = {videoTags: {$all: req.body.tags}};
}
let query = {
$and: [
{
user_id: {$nin:
myUserId
}
},
{ date: { $gte: dateMax, $lt: dateMin } },
tags
],
}
and then Document.find(query). The problem is no matter how I modify tags (whether undefined, as whitespace, or otherwise) I get various errors like $or/$and/$nor entries need to be full objects and TypeError: Cannot read property 'hasOwnProperty' of undefined.
Is there a way to build an optional requirement into the query?
I tried the option below and the query is just returning everything that matches the other fields. For some reason it isn't filtering by tags. I did a console.log(queryArr) and console.log(query) get the following respectively:
[
{ user_id: { '$nin': [Array] } },
{
date: {
'$gte': 1985-01-01T00:00:00.000Z,
'$lt': 2020-01-01T00:00:00.000Z
}
},
push: { documentTags: { '$all': [Array] } }
]
console.log(query)
{
'$and': [
{ user_id: [Object] },
{ date: [Object] },
push: { documentTags: [Object] }
]
}
You are almost there. Instead you could construct the object outside the query and just put the constructed query in $and when done..
let queryArr = [
{
user_id: {$nin: myUserId}
},
{ date: { $gte: dateMax, $lt: dateMin } }
];
if (req.body.tags) {
queryArr.push({videoTags: {$all: req.body.tags}});
}
let query = {
$and: queryArr
}
Now you can control the query by just pushing object into the query Array itself.
I figured out why it wasn't working. Basically, when you do myVar.push it creates a key-value pair such as [1,2,3,push:value]. This would work if you needed to append a k-v pair in that format, but you'll have difficulty using it in a query like mine. The right way for me turned out to be to use concact which appends the array with just the value that you set, rather than a k-v pair.
if (req.body.tags){
queryArgs = queryArgs.concat({documentTags: {$all: tags}});
}
let query = {
$and: queryArgs
}

Right outer join in aggregation pipeline

I have two collections, let's call them Cats and Parties, with the following schemas:
Cat
{ name: String }
Party
{ date: Date, attendants: [{ cat: { ref: 'Cat' }, role: String }] }
where role symbolizes some other attribute, say, whether the attending cat is a VIP member.
Now I want to get a list of all cats that exist (even those poor kitties who never attended any party) and for each cat, I want a list of all the roles it ever had for at least one party. Furthermore, I want this entire list to be sorted by the (per cat) last attended party's date with cats who never attended any party being last.
This raises the following problems for me:
Aggregrating over Parties excludes party-pooper kitties who never joined a party.
Aggregating over Cats sort of goes »the wrong way« because I cannot $lookup parties the cat attended because that information is in a subdocument array.
The pipeline I currently have gives me all cats who attended at least one party with a list of their roles, but doesn't sort by the last attended party. In fact, I could live with excluding cats who never attended a party, but the sorting is crucial for me:
Party.aggregate([
{ $unwind: '$attendants' },
{ $project: { role: '$attendants.role', cat: '$attendants.cat' } },
{
$group: {
_id: '$cat',
roles: { $addToSet: '$role' }
}
},
{
$lookup: {
from: 'cats',
localField: '_id',
foreignField: '_id',
as: 'cat'
}
},
{ $unwind: '$cat' },
// (*)
{ $addFields: { 'cat.roles': '$roles' } },
{ $replaceRoot: { newRoot: '$cat' } }
])
My current idea would basically be a right outer join at (*) to add a list of parties the cat has attended, $project that to the party's date and then $group using $max to get the latest date. Then I can $unwind that now one-element array and $sort over it in the end.
The problem is that right outer joins don't exist in mongo, AFAIK, and I don't know how to get that list of parties per cat within the pipeline.
To clarify, the expected output should be something like
[
{
"_id": "59982d3c7ca25936f8c327c8",
"name": "Mr. Kitty",
"roles": ["vip", "birthday cat"],
"dateOfLastParty": "2017-06-02"
},
{
"_id": "59982d3c7ca25936f8c327c9",
"name": "Snuffles",
"roles": ["best looking cat"],
"dateOfLastParty": "2017-06-01"
},
...
{
"_id": "59982d3c7ca25936f8c327c4",
"name": "Sad Face McLazytown",
"roles": [],
"dateOfLastParty": null
},
]
As stated, you want the "cats" so use the Cat model and do the "left outer join" that is actually inherent to $lookup, rather than asking for a "right outer join" from the opposing collection, since a "right outer join" is not possible with MongoDB at this time.
It's also far more practical as a "left join", because you want "cats" as your primary source of output. The only thing to consider when linking to "Party" is that each "Cat" is listed in an array, and therefore you get the whole document back. So all that needs to be done is in "post processing" after the $lookup, you simply "filter" the array content for the matching entry of the current cat.
Fortunately we get good features with $arrayElemAt and $indexOfArray, that allow us to do that exact extraction:
let kitties = await Cat.aggregate([
{ '$lookup': {
'from': Party.collection.name,
'localField': '_id',
'foreignField': 'attendants.cat',
'as': 'parties'
}},
{ '$replaceRoot': {
'newRoot': {
'$let': {
'vars': {
'parties': {
'$map': {
'input': '$parties',
'as': 'p',
'in': {
'date': '$$p.date',
'role': {
'$arrayElemAt': [
'$$p.attendants.role',
{ '$indexOfArray': [ '$$p.attendants.cat', '$_id' ] }
]
}
}
}
}
},
'in': {
'_id': '$_id',
'name': '$name',
'roles': '$$parties.role',
'dateOfLastParty': { '$max': '$$parties.date' }
}
}
}
}}
]);
So my concept of "optimal" processing here actually uses $replaceRoot here because you can define the whole document under a $let statement. The reason I'm doing that is so we can take the "parties" array output from the previous $lookup and reshape each entry extracting the matching "role" data for the current "kitty" at that given party. This we can actually make a variable itself.
The reason for the "array variable" is because we can then use $max to extract the "largest/last" date property as "singular" and still extract the "role" values as an "array" from that reshaped content. This makes it easy to define the fields you wanted.
And since it was a "left join" started from Cat in the first place, then those poor kitties that missed out on all parties are still there, and still have the desired output.
Two aggregation pipeline stages. What could be more simple!
As a full listing:
const mongoose = require('mongoose'),
Schema = mongoose.Schema;
mongoose.Promise = global.Promise;
mongoose.set('debug',true);
const uri = 'mongodb://localhost/catparty',
options = { useMongoClient: true };
const catSchema = new Schema({
name: String
});
const partySchema = new Schema({
date: Date,
attendants: [{
cat: { type: Schema.Types.ObjectId, ref: 'Cat' },
role: String
}]
});
const Cat = mongoose.model('Cat', catSchema);
const Party = mongoose.model('Party', partySchema);
function log(data) {
console.log(JSON.stringify(data,undefined,2))
}
(async function() {
try {
const conn = await mongoose.connect(uri,options);
// Clean collections
await Promise.all(
Object.keys(conn.models).map( m => conn.models[m].remove({}) )
);
var cats = await Cat.insertMany(
['Fluffy', 'Snuggles', 'Whiskers', 'Socks'].map( name => ({ name }) )
);
cats.shift();
cats = cats.map( (cat,idx) =>
({ cat: cat._id, role: (idx === 0) ? 'Host' : 'Guest' })
);
log(cats);
let party = await Party.create({
date: new Date(),
attendants: cats
});
log(party);
let kitties = await Cat.aggregate([
{ '$lookup': {
'from': Party.collection.name,
'localField': '_id',
'foreignField': 'attendants.cat',
'as': 'parties'
}},
{ '$replaceRoot': {
'newRoot': {
'$let': {
'vars': {
'parties': {
'$map': {
'input': '$parties',
'as': 'p',
'in': {
'date': '$$p.date',
'role': {
'$arrayElemAt': [
'$$p.attendants.role',
{ '$indexOfArray': [ '$$p.attendants.cat', '$_id' ] }
]
}
}
}
}
},
'in': {
'_id': '$_id',
'name': '$name',
'roles': '$$parties.role',
'dateOfLastParty': { '$max': '$$parties.date' }
}
}
}
}}
]);
log(kitties);
} catch(e) {
console.error(e);
} finally {
mongoose.disconnect();
}
})();
And example output:
[
{
"_id": "59a00d9528683e0f59e53460",
"name": "Fluffy",
"roles": [],
"dateOfLastParty": null
},
{
"_id": "59a00d9528683e0f59e53461",
"name": "Snuggles",
"roles": [
"Host"
],
"dateOfLastParty": "2017-08-25T11:44:21.903Z"
},
{
"_id": "59a00d9528683e0f59e53462",
"name": "Whiskers",
"roles": [
"Guest"
],
"dateOfLastParty": "2017-08-25T11:44:21.903Z"
},
{
"_id": "59a00d9528683e0f59e53463",
"name": "Socks",
"roles": [
"Guest"
],
"dateOfLastParty": "2017-08-25T11:44:21.903Z"
}
]
And you should be able to see how those "roles" values actually become an array with more data. And if you need that to be a "unique list", then simply wrap with $setDifference as in:
'roles': { '$setDifference': [ '$$parties.role', [] ] },
And that is also covered

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