I am running the following aggregation pipeline:
const agg = [
{
'$match': {
'aaa': 'bbb'
}
}, {
'$group': {
'_id': '',
'total': {
'$sum': '$num'
}
}
}
];
My problem is, when $match matches nothing, the pipeline returns 0 documents. How do I get the pipeline to always return 1 document?
In MongoDB version 6.0 you can do it like this one:
db.collection.aggregate([
{ $match: { aaa: 'bbb' } },
{
$group: {
_id: null,
total: { $sum: "$num" }
}
},
{
$densify: {
field: "total",
range: { step: 1, bounds: [0, 0] }
}
},
{ $set: { _id: { $cond: [{ $eq: [{ $type: "$_id" }, "missing"] }, MaxKey, "$_id"] } } },
{ $sort: { _id: 1 } },
{ $limit: 1 }
])
In version < 6.0 you can try this one:
db.collection.aggregate([
{
$facet: {
data: [
{ $match: { aaa: 'bbb' } },
{ $group: { _id: null, total: { $sum: "$num" } } }
],
default: [
{ $limit: 1 },
{ $group: { _id: null, total: { $sum: 0 } } },
{ $set: { _id: MaxKey } }
]
}
},
{ $replaceWith: { $mergeObjects: [{ $first: "$default" }, { $first: "$data" }] } },
])
Or this one:
db.collection.aggregate([
{ $match: { aaa: 'bbb' } },
{ $group: { _id: null, total: { $sum: "$num" } } },
{
$unionWith: {
coll: "collection",
pipeline: [
{ $limit: 1 },
{ $set: { _id: MaxKey, total: 0 } },
{ $project: { _id: 1, total: 1 } }
]
}
},
{ $sort: { _id: 1 } },
{ $limit: 1 }
])
Related
I've created an aggregate query but for some reason it doesn't seem to work for custom fields created in the aggregation pipeline.
return this.repository.mongo().aggregate([
{
$match: { q1_avg: { $regex: baseQuery['value'], $options: 'i' } }, // NOT WORKING
},
{
$group: {
_id: '$product_sku',
id: { $first: "$_id" },
product_name: { $first: '$product_name' },
product_category: { $first: '$product_category' },
product_sku: { $first: '$product_sku' },
q1_cnt: { $sum: 1 },
q1_votes: { $push: "$final_rating" }
},
},
{
$facet: {
pagination: [ { $count: 'total' } ],
data: [
{
$project: {
_id: 1,
id: 1,
product_name: 1,
product_category: 1,
product_sku: 1,
q1_cnt: 1,
q1_votes: {
$filter: {
input: '$q1_votes',
as: 'item',
cond: { $ne: ['$$item', null] }
}
},
},
},
{
$set: {
q1_avg: { $round: [ { $avg: '$q1_votes' }, 2 ] },
}
},
{ $unset: ['q1_votes'] },
{ $skip: skip },
{ $limit: limit },
{ $sort: sortList }
]
}
},
{ $unwind : "$pagination" },
]).next();
q1_avg value is an integer and as far as I know, regex only works with strings. Could that be the reason
I have a collection that looks like below:
[
{
"orderNum": "100",
"createdTime": ISODate("2020-12-01T21:00:00.000Z"),
"amount": 100,
"memo": "100memo",
"list": [
1
]
},
{
"orderNum": "200",
"createdTime": ISODate("2020-12-01T21:01:00.000Z"),
"amount": 200,
"memo": "200memo",
"list": [
1,
2
]
},
{
"orderNum": "300",
"createdTime": ISODate("2020-12-01T21:02:00.000Z"),
"amount": 300,
"memo": "300memo"
},
{
"orderNum": "400",
"createdTime": ISODate("2020-12-01T21:03:00.000Z"),
"amount": 400,
"memo": "400memo"
},
]
and I'm trying to get the total amount of orders that were created before order# 300 (so order#100 and #200, total amount is 300).
Does anyone know how to get it via Mongoose?
You can use this one:
db.collection.aggregate([
{ $sort: { orderNum: 1 } }, // by default the order of documents in a collection is undetermined
{ $group: { _id: null, data: { $push: "$$ROOT" } } }, // put all documents into one document
{ $set: { data: { $slice: ["$data", { $indexOfArray: ["$data.orderNum", "300"] }] } } }, // cut desired elementes from array
{ $unwind: "$data" }, // transform back to documents
{ $replaceRoot: { newRoot: "$data" } },
{ $group: { _id: null, total_amount: { $sum: "$amount" } } } // make summary
])
Actually it is not needed to $unwind and $group, so the shortcut would be this:
db.collection.aggregate([
{ $sort: { orderNum: 1 } },
{ $group: { _id: null, data: { $push: "$$ROOT" } } },
{ $set: { data: { $slice: ["$data", { $indexOfArray: ["$data.orderNum", "300"] }] } } },
{ $project: { total_amount: { $sum: "$data.amount" } } }
])
But the answer from #turivishal is even better.
Update for additional field
{
$set: {
data: { $slice: ["$data", { $indexOfArray: ["$data.orderNum", "300"] }] },
memo: { $arrayElemAt: [ "$data.memo", { $indexOfArray: ["$data.orderNum", "300"] } ] }
}
}
or
{ $set: { data: { $slice: ["$data", { $indexOfArray: ["$data.orderNum", "300"] }] } } },
{ $set: { memo: { $last: { "$data.memo" } } },
$match orderNum less than 300
$group by null and get totalAmount using $sum of amount
YourSchemaModel.aggregate([
{ $match: { orderNum: { $lt: "300" } } },
{
$group: {
_id: null,
totalAmount: { $sum: "$amount" }
}
}
])
Playground
I have the following stage in my MongoDB aggregation pipeline that returns the qty and sum of sales, which works fine:
{
$lookup: {
from: 'sales',
let: { part: '$_id' },
pipeline: [
{ $match: { $and: [{ $expr: { $eq: ['$partner', '$$part'] } }] } },
{ $group: { _id: null, qty: { $sum: 1 }, soldFor: { $sum: '$soldFor' } } },
{ $project: { _id: 0, qty: 1, soldFor: 1 } }],
as: 'sales'}},
{ $unwind: { path: '$sales', preserveNullAndEmptyArrays: true } },
{ $project: { _id: 1, sales: 1 }
}
However, if there are no sales, then the $project projection returns an empty sales object, but what I'd really like is it to return a completed object, but with 0 - like this:
{
sales: {
qty: 0,
soldFor: 0
}
}
You can use $cond operator here
{
"$project": {
"_id": 1,
"sales": {
"$cond": [
{ "$eq": [{ "$size": "$sales" }, 0] },
{
"sales": {
"qty": 0,
"soldFor": 0
}
},
"$sales"
]
}
}
}
I have a collection with documents such as these.
What I want to do is get all distinct clusters coming from the document with the highest (recent) lastupdate field.
I think this should be the output:
[
"19":"Income2",
"20":"Income Modified",
"21":"Income Modified"
]
Please try this :
db.yourCollection.aggregate([{ $unwind: '$meta.clusters' },
{ $project: { '_id': { $objectToArray: '$meta.clusters' }, 'last_update': 1 } }, { $sort: { 'last_update': -1 } },
{ $group: { _id: '$_id.k', values: { $first: '$$ROOT' } } }, { $sort: { 'values.last_update': -1 } },
{ $replaceRoot: { 'newRoot': '$values' } },
{ $group: { _id: '', distinctCLusters: { $push: { $arrayToObject: "$_id" } } } }, { $project: { _id: 0 } }])
Output with provided data:
{
"distinctCLusters" : [
{
"21" : "Income Modified"
},
{
"19" : "Income2"
},
{
"20" : "Income Modified"
}
]
}
I want to add Not in query. but unfortunately I'm not getting the required result. i want to get result where user is not equal to userid. But I'm confused as to how I can add that. I tried multiple scenarios but failed.
server.get('/myFeedback', (req, res) => {
var userid = req.query.userID;
//console.log(req.query);
db.collection("tweetsWithSentimentFeedback").aggregate( [
{
$group: {
_id: {
topic: "$topic",
group : "$group",
type : "$type",
user : "$userName"
},
count: { $sum: 1 }
}
},{ $group: {
_id: {
topic: "$_id.topic",
group : "$_id.group",
},
typeAndCount: {
$addToSet: {
type: "$_id.type",
count: "$count"
}
},
userName: {
$addToSet: {
user: "$_id.userName"
}
},
totalCount: {
$sum: "$count"
}
}
},
{ $match: { $and: [ { totalCount: { $gt: 0, $lt: 15 } }, {userEqual: { $ne: [ "$userName.user", userid ] }} ] } },
// Then sort
{ "$sort": { "totalCount": -1 } }
], (err, result) => {
if (err) {
console.log(err);
}
res.status(200).send(result);
} );
});
You should add a $match as a first stage to filter the user.
{ $match: { userName: { $ne: userid } } }
Update:
db.collection("tweetsWithSentimentFeedback").aggregate(
[{
$group: {
_id: {
topic: "$topic",
group: "$group",
type: "$type",
user: "$userName"
},
count: {
$sum: 1
}
}
}, {
$group: {
_id: {
topic: "$_id.topic",
group: "$_id.group"
},
typeAndCount: {
$addToSet: {
type: "$_id.type",
count: "$count"
}
},
userName: {
$addToSet: "$_id.userName"
},
totalCount: {
$sum: "$count"
}
}
}, {
$match: {
{
totalCount: {
$gt: 0,
$lt: 15
}
},
{
userName: {
$ne: userid
}
}
}
}, , {
$sort: {
totalCount: -1
}
}])