$group with nested array element - javascript

would like to know how to use MongoDB's aggregation to collectively summarize a count of each reason_id:
I would like to get known that there are 2 counts for having "reason_id = KW7Kcsv7835YZeE3n", and 1 count for having "reason_id = KNcKQCjhFzha3oLfE".
Here is my data:
[
{
"_id": "2DLQFJLbZScBXpSam",
"toilet_id": "bJsyfh3TCvpTzE2mJ",
"reason_ids": [
"KNcKQCjhFzha3oLfE",
"KW7Kcsv7835YZeE3n"
],
"score_id": null,
"toilet": {
"_id": "bJsyfh3TCvpTzE2mJ",
"name": "Toilet_M_1",
"gender": "m",
"mac_address": "11:11:11:11:11:11"
}
},
{
"_id": "akjsbcjascklsacas",
"toilet_id": "bJsyfh3TCvpTzE2mJ",
"reason_ids": [
"KW7Kcsv7835YZeE3n"
],
"score_id": null,
"toilet": {
"_id": "fsgndgklndsdsdsd",
"name": "Toilet_F_1",
"gender": "f",
"mac_address": "11:11:11:11:11:11"
}
},
]


You can try this
db.collection.aggregate([
{
"$unwind": "$reason_ids"
},
{
"$group": {
"_id": "$reason_ids",
"count": {
"$sum": 1
}
}
}
])
Output
[
{
"_id": "KW7Kcsv7835YZeE3n",
"count": 2
},
{
"_id": "KNcKQCjhFzha3oLfE",
"count": 1
}
]
Try it here

Related

mongodb: How to use variable inside group operator in aggregate operation?

I am tring to make a query where use the value and try to interpolate a string in a new field.
Mongo Database:
[
{
"state": "1",
"events": {
"1": [
{
"date": 123.2,
"msg": "msg1"
},
{
"date": 124.2,
"msg": "msg2"
}
],
"2": [
{
"date": 125.2,
"msg": "msg3"
},
{
"date": 126.2,
"msg": "msg4"
}
],
}
},
{
"state": "2",
"events": {
"1": [
{
"date": 123.2,
"msg": "msg1"
},
{
"date": 124.2,
"msg": "msg2"
}
],
"2": [
{
"date": 125.2,
"msg": "msg3"
},
{
"date": 126.2,
"msg": "msg4"
}
],
}
}
]
Aggregate query:
db.collection.aggregate({
"$match": {
"state": {
"$in": [
"1",
"2"
]
}
}
},
{
"$group": {
"_id": {
"state": "$state"
},
"this_path": {
"$first": {
"$concat": [
"events.",
"$state",
".0.date"
]
}
}
}
})
"this_path" gets "events.1.0.date", but how to use this value, in another query(line), I would like to do like a string interpolation. Some thing like
...
"date": {
"$first": { `\$${this_path}`}
...
so it become the "events.1.date" then "$events.1.0.date" then "123.2"

you can define it by let just for example a fragment from pipeline:
$lookup: {
from: contentCollectionName,
as: 'content',
let: {
parentId: '$id',
},
The id is taken from above matched documents, but it can be anything

MongoDb: How to get Group by's total count as a flat count instead of in an array?

This is hard for me to put in words, so I am going to try and explain with a code example:
Working MongoDb Playground
db.collection.aggregate([
{
"$facet": {
"countByStatus": [
{
"$group": {
"_id": "$status.name",
"count": {
"$sum": 1
}
}
}
],
"totalCount": [
{
"$group": {
"_id": null,
"count": {
"$sum": 1
}
}
}
]
}
}
])
Output:
[
{
"countByStatus": [
{
"_id": "Approved",
"count": 2
},
{
"_id": "Rejected",
"count": 1
}
],
"totalCount": [
{
"_id": null,
"count": 3
}
]
}
]
Desired Output:
[
{
"countByStatus": [
{
"_id": "Approved",
"count": 2
},
{
"_id": "Rejected",
"count": 1
}
],
"totalCount": 3 //totalCount is a flat count instead of array here
}
]
I could execute the query get the result and then pick first element of array[0].count but I want to know if this could be done natively?

It can be done in a single stage with $let:
{
$project: {
countByStatus: 1,
totalCount: {
$let: {
vars: { first: { $arrayElemAt: [ "$totalCount", 0 ] } },
in: "$$first.count"
}
}
}
}
Mongo Playground

find match data inside the arrays by filtering

In my collection I have to find the operator_name match by date and inside array match by shift_name
{
"_id": "5eb301bc0218ff48b724a486",
"date": "2020-07-02T00:00:00.000Z",
"shift_wise": [{
"_id": "5eb3037d3cb4d74b749fc22b",
"shift_name": "Shift A",
"operator_name": "5eb2ec3420fbc132eb648a6d"
},
{
"_id": "5eb3037d3cb4d74b749fc22c",
"shift_name": "Shift B",
"operator_name": "5eb2ec3420fbc132eb648a6d"
},
{
"_id": "5eb3037d3cb4d74b749fc22d",
"shift_name": "Shift C",
"operator_name": "5eb2ec3420fbc132eb648a6d"
}
],
"createdAt": "2020-05-06T18:28:12.379Z",
"updatedAt": "2020-05-06T18:35:41.484Z",
"__v": 4
}

db.collection.aggregate([
{
$unwind: "$shift_wise"
},
{
$match: {
date: "2020-07-02T00:00:00.000Z",
"shift_wise.shift_name": "Shift A"
}
},
{
$project: {
_id: 0,
operatorName: "$shift_wise.operator_name"
}
}
])
result:
{
"operatorName": "5eb2ec3420fbc132eb648a6d"
}
test: https://mongoplayground.net/p/yHfwOB3tlyx

Aggregate array occourances

I have a set of documents (posts) which have an array of users mentioned in each post.
{
"title": "Some post title",
[ ... ]
"mentions": ["johnsmith", "johndoe", "paul"]
}
I want to aggregate a list of unique mentions, and the number of times they've been mentioned across all posts. For example:
[{ user: "johnsmith", count: 5 }, { user: "benlewis", count: 9 }, { user: "johndoe", count: 1 }]
With Mongo, I'd do something like:
"mentions": [{
"$unwind": "$mentions"
}, {
"$group": {
"_id": "$mentions",
"count": { "$sum": 1 }
}
}]
What's the equivalent in Elasticsearch?

You can use a Terms aggregation for that. A small (5.x) example:
PUT test
{
"mappings": {
"test" : {
"properties": {
"title": {
"type": "text"
},
"mentions": {
"type": "keyword"
}
}
}
}
}
POST test/test/1
{
"title": "Some post title",
"mentions": [
"johnsmith",
"johndoe",
"paul"
]
}
POST test/test/2
{
"title": "Some post title 2",
"mentions": [
"johnsmith"
]
}
GET test/_search
{
"size": 0,
"aggs": {
"test": {
"terms": {
"field": "mentions",
"size": 10
}
}
}
}
Gives the following response:
"aggregations": {
"test": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": "johnsmith",
"doc_count": 2
},
{
"key": "johndoe",
"doc_count": 1
},
{
"key": "paul",
"doc_count": 1
}
]
}
}
}
Hope this helps :)

Compare two arrays of objects and filter results

Example:
const depositAddress = '2NBXPR5PRtW8xBRuDnWXBDXqHYpDPupWnhG';
DBarray1.forEach( (tx) => {
console.log(tx);
})
TXarray2.forEach( (sim) => {
console.log(sim);
});
DBarray1 = [
{
"_id": "575e2b7875a402111900ba8f",
"username": "aleluia#gmail.com",
"playerWallet": "2NFt8YfydBU5JD9U8Xq2ucbfUp2sP7BjUrh",
"User_Profile": {
"TXHash": [
"7fbe28f75412f19dfd123a08ce03c33c302aa13d1e68d38ab8cb4c7418777f8e"
]
}
},
{
"_id": "575e2946b909906a17ea65b9",
"username": "super#user.com",
"playerWallet": "2MzppxEX7xMidjhoJGczFDYsHk5TQwFkjS3",
"User_Profile": {
"TXHash": [
"cf948340a40d3302303dfb3710cfce37bb1cd156dcb6c74561fdc71c0a8fc30b",
"6219def49d2e8284a6031f4c7e05e21adf756d38904e6359bd7844ae14c75a50"
]
}
}
] // end console.log(DBarray1);
TXarray2 = [
{
"id": "cf948340a40d3302303dfb3710cfce37bb1cd156dcb6c74561fdc71c0a8fc30b",
"normalizedHash": "f62af1a61c7eb569c1a171ad23c70bc218bd7244c9c5c92cf7d98638314fbbc5",
"date": "2016-06-21T04:11:18.541Z",
"fee": 6280,
"inputs": [
{
"previousHash": "2660fb761354671912b0cea6427e9ee91a98a507e5f1408865a6058b566b508c",
"previousOutputIndex": 0
},
{
"previousHash": "ce3ef138c11ea4d1766cce52ccf5f1e91790bc03b56561b0eb669041bae4e1a3",
"previousOutputIndex": 0
}
],
"outputs": [
{
"vout": 0,
"account": "2N92kApgroS6CTVuTajtjWtpcAZpUiyQoDT",
"value": 861003
},
{
"vout": 1,
"account": "2NBXPR5PRtW8xBRuDnWXBDXqHYpDPupWnhG",
"value": 3100000,
"isMine": true,
"chain": 0,
"chainIndex": 0
}
],
"entries": [
{
"account": "2MzppxEX7xMidjhoJGczFDYsHk5TQwFkjS3",
"value": -3967283
},
{
"account": "2N92kApgroS6CTVuTajtjWtpcAZpUiyQoDT",
"value": 861003
},
{
"account": "2NBXPR5PRtW8xBRuDnWXBDXqHYpDPupWnhG",
"value": 3100000
}
],
"confirmations": 70,
"pending": false,
"instant": true,
"instantId": "5768be65427689eb06e597559c7e6cf0",
"blockhash": "00000000002d9fb51c7c3c1607fe062eff686aa6be657a59fee6c3044963897d",
"height": 872152
},
{
"id": "6219def49d2e8284a6031f4c7e05e21adf756d38904e6359bd7844ae14c75a50",
"normalizedHash": "179a4466fdfc5470e99e43aa177d43aa4f09e3a06760fd5bebffdda080d4407f",
"date": "2016-06-21T04:13:23.650Z",
"fee": 9096,
"inputs": [
{
"previousHash": "5d2879a79ea3d0dcb50049ef9ca46ef7e8d82caf2073a299a6cd0332add404c8",
"previousOutputIndex": 1
},
{
"previousHash": "d75288e69a3fc2edd534ddcd845af6a280a27af58013ae82828c8a8f813829c1",
"previousOutputIndex": 0
},
{
"previousHash": "eea4f9b274708b60c1b030203543a155857bc54aa11055ada04aceee706f96b9",
"previousOutputIndex": 0
}
],
"outputs": [
{
"vout": 0,
"account": "2NBXPR5PRtW8xBRuDnWXBDXqHYpDPupWnhG",
"value": 2000000,
"isMine": true,
"chain": 0,
"chainIndex": 0
},
{
"vout": 1,
"account": "2MzFTm5jnCDiAapjNnyVgZAJrXMKfQ74esV",
"value": 9859
}
],
"entries": [
{
"account": "2MzcwVFKF274bMNT5tNEDY7Ua7bAgvFUdu9",
"value": -35316
},
{
"account": "2MzFTm5jnCDiAapjNnyVgZAJrXMKfQ74esV",
"value": 9859
},
{
"account": "2MzppxEX7xMidjhoJGczFDYsHk5TQwFkjS3",
"value": -1983639
},
{
"account": "2NBXPR5PRtW8xBRuDnWXBDXqHYpDPupWnhG",
"value": 2000000
}
],
"confirmations": 70,
"pending": false,
"instant": true,
"instantId": "5768bee2b5bdf3f406e7db035aef016a",
"blockhash": "00000000002d9fb51c7c3c1607fe062eff686aa6be657a59fee6c3044963897d",
"height": 872152
},
{
"id": "7fbe28f75412f19dfd123a08ce03c33c302aa13d1e68d38ab8cb4c7418777f8e",
"normalizedHash": "b4f1974dccde5ea9dfb0abcd7d4a6f3f14995d9dd422aa7d2a9078229ff18ff4",
"date": "2016-06-21T03:39:25.034Z",
"fee": 3465,
"inputs": [
{
"previousHash": "97fbb6ed8646f7ce9ed10a4230a70348151d5b6b208ad068e3a1a3fddae2dc0e",
"previousOutputIndex": 2
}
],
"outputs": [
{
"vout": 0,
"account": "2NBXPR5PRtW8xBRuDnWXBDXqHYpDPupWnhG",
"value": 111200000,
"isMine": true,
"chain": 0,
"chainIndex": 0
},
{
"vout": 1,
"account": "2NFJnLrhsCDfG3ooQvGC169gnzBabtRgV2y",
"value": 244246993
}
],
"entries": [
{
"account": "2NCGUnwpNgaJbhMZKLJcBrWvZhWnai5PjVC",
"value": -355450458
},
{
"account": "2NFJnLrhsCDfG3ooQvGC169gnzBabtRgV2y",
"value": 244246993
},
{
"account": "2NBXPR5PRtW8xBRuDnWXBDXqHYpDPupWnhG",
"value": 111200000
}
],
"confirmations": 77,
"pending": false,
"instant": false,
"blockhash": "0000000000509dbc80cc3d86cdb10ce8e87ab7867c6775a9b00ca904fbe70da7",
"height": 872145
}
]// end console.log(TXarray2);
How can we check if TXarray2.id which is the transactions id, if it matches a payment made by the user inside DBarray1.User_Profile.TXHash for examplecf948340a40d3302303dfb3710cfce37bb1cd156dcb6c74561fdc71c0a8fc30b .
I want to know forEach TXarray2.id who made the payment . I tried to do this with promises and i will share some code when i get home but i'm sure it can be done with async for all users one by one and log who made a payment today to this wallet. I tried with array.find() method to check inside TXHash but failed, i don't fully grasp many prototype methods yet...
Hopefully someone already thinks this a walk on the park for him and found a better solution to validate this kind of stuff. I will accept any answer even with lodash, maping, anything. TY !!!

You iterate TXArray2 and do a lookup in DBarray1 for the transactionId.
I like to work with native array methods like map and filter, so I would use something like the following:
const result = TXarray2.map(tx => ({
transaction: tx,
user: DBarray1.filter(user => user.User_Profile.TXHash.indexOf(tx.id) > -1)[0]
}));
In this example result is an array where every element contains a transaction and the matching user.

If you already have all of the transaction and user data, could you do something like this?
// for each transaction in TXarray2
for (let { 'id': transactionId } of TXarray2) {
// check each entry in DBarray1
for (let { '_id': userId, 'User_Profile': { 'TXHash': transactions } } of DBarray1) {
if (transactions.includes(transactionId)) {
console.log(`${transactionId} was made by ${userId}`);
}
}
}

The best way here is to use Array.indexOf (or Array.findIndex if you want to use callbacks) which returns -1 if an entry is not in an array.
Here's the sync variant:
var paid = [];
TXArray2.forEach(function(transaction){
for(var i = 0; i < DBArray1.length; ++i){
if(DBArray1[i].User_Profile.TXHash.indexOf(transaction.id) > -1){
paid.push({
user : DBArray1[i],
transaction : transaction
});
break;
}
}
});
console.log(paid);

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