Get sum of a column from mongodb along with the list of another column - mongodb

Question

I have a collection "employees" with sample entries as below-
{
"_id" : ObjectId("62ccaa238a322322211"),
"employeeId" : "1234",
"date" : ISODate("2022-07-11T12:00:00.000+0000"),
"hours" : 15.0,
"createdBy" : "user1",
"createdDate" : ISODate("2023-02-19T21:54:27.213+0000"),
"updatedBy" : "user1",
"updatedDate" : ISODate("2023-02-19T21:54:27.213+0000"),
},
{
"_id" : ObjectId("62ccaa238a322388821"),
"employeeId" : "1234",
"date" : ISODate("2022-07-10T12:00:00.000+0000"),
"hours" : 25.0,
"createdBy" : "user1",
"createdDate" : ISODate("2023-02-19T22:54:27.213+0000"),
"updatedBy" : "user1",
"updatedDate" : ISODate("2023-02-19T22:54:27.213+0000"),
}
I am trying to get sum of hours for each employee along with the list of dates for those entries
{
employeeId :"1234"
hours : 40 // sum of the hours from both entries
dates : [2022-07-11, 2022-07-10] // list of `date` column
}
I tried below one but dont know how to adapt to get employeeId and sum
db.getCollection("employees").aggregate( [
{ $match : {
$and :[
{"employeeId" : "1234"},
{"date" : { $lte: new ISODate("2023-02-19") }}
]}},
{
$group:
{
"_id": {
"$dateToString": {
"format": "%Y-%m-%d",
"date": "$date"
}
},
totalAmount: { $sum: "$hours" }
}
}
] )

Answer 1

You should group by employeeId instead of date.
db.collection.aggregate([
{
$group: {
_id: "$employeeId",
hours: {
$sum: "$hours"
},
dates: {
$push: {
$dateTrunc: {
date: "$date",
unit: "day"
}
}
}
}
}
])
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