Get data for month wise in mongodb - mongodb

Question

I want to get data to each month. in my table data is stored like this:-
"patient" : [
{
"status" : 'arrived',
start_time: '2017-08-17T09:17:00.000Z
},
{
"status" : 'arraived',
start_time: '2017-08-16T07:17:00.000Z
},
{
"status" : 'arrived',
start_time: '2017-07-12T09:17:00.000Z
},
{
"status" : 'arraived',
start_time: '2017-07-05T08:10:00.000Z
},
{
"status" : 'arrived',
start_time: '2017-06-02T09:17:00.000Z
},
{
"status" : 'arraived',
start_time: '2017-05-05T08:16:00.000Z
}
]
etc,
and I want to sum of patient of each month (jan to des), like this :-
{
"month" : 8,
"count" : 2
}and like this month 1 to 12

Answer 1

I assume, patient array is associated with a customer and the date is stored in mongo ISO format.
So, the actual document would look like :
{
name: "stackOverflow",
"patient" : [
{
"status" : 'arrived',
"start_time": ISODate("2017-08-17T09:17:00.000Z")
},
{
"status" : 'arraived',
"start_time": ISODate("2017-08-16T07:17:00.000Z")
},
{
"status" : 'arrived',
"start_time": ISODate("2017-07-12T09:17:00.000Z")
},
{
"status" : 'arraived',
"start_time": ISODate("2017-07-05T08:10:00.000Z")
},
{
"status" : 'arrived',
"start_time": ISODate("2017-06-02T09:17:00.000Z")
},
{
"status" : 'arraived',
"start_time": ISODate("2017-05-05T08:16:00.000Z")
}
]
}
here is a sample query which you can try -
db.test.aggregate([
{$unwind: "$patient"},
{ $group: {
_id: {name: "$name", month: {$month: "$patient.start_time"}},
count: { $sum: 1}
}},
{$group: {
_id: "$_id.name",
patient: {$push: {month: "$_id.month", count: "$count"}}
}}
])
Sample output:
{
"_id" : "stackOverflow",
"patient" : [
{
"month" : 5,
"count" : 1
},
{
"month" : 6,
"count" : 1
},
{
"month" : 7,
"count" : 2
},
{
"month" : 8,
"count" : 2
}
]
}
You can change query according to your use-case. hope this will help you!

Answer 2

This is my code:-
db.appointments.aggregate( [
{
$project:
{
"patient_id": 1,
"start_time": 1,
"status": 1
}
},
{
$match: {
'start_time' : { $gte: startdate.toISOString() },
'status': { $eq: 'arrived' }
} ,
},
{ $group: {
_id: {id: "$_id", start_time: {$month: "$appointments.start_time"}},
count: { $sum: 1}
}}
])
When I used this :-
{ $group: {
_id: {id: "$_id", start_time: {$month: "$start_time"}},
count: { $sum: 1}
}
}
its showing error message:-
{"name":"MongoError","message":"can't convert from BSON type missing to Date","ok":0,"errmsg":"can't convert from BSON type missing to Date","code":16006,"codeName":"Location16006"}
And when I comment this its showing this :-
Out Put here:-
:[{"count":{"_id":"595b6f95ab43ec1f6c92b898","patient_id":"595649904dbe9525c0e036ef","start_time":"2017-07-04T10:35:00.000Z","status":"arrived"}},
{"count":{"_id":"595dff870960d425d4f14633","patient_id":"5956478b4dbe9525c0e036ea","start_time":"2017-03-08T09:14:00.000Z","status":"arrived"}},{"count":{"_id":"595dffaa0960d425d4f14634","patient_id":"595649904dbe9525c0e036ef","start_time":"2017-03-17T09:15:00.000Z","status":"arrived"}},{"count":{"_id":"595dffcf0960d425d4f14635","patient_id":"595648394dbe9525c0e036ec","start_time":"2017-06-08T09:15:00.000Z","status":"arrived"}},{"count":{"_id":"595dfffb0960d425d4f14636","patient_id":"5956478b4dbe9525c0e036ea","start_time":"2017-06-20T09:16:00.000Z","status":"arrived"}},{"count":{"_id":"595e00160960d425d4f14637","patient_id":"5959ea7f80388b19e0b57817","start_time":"2017-08-17T09:17:00.000Z","status":"arrived"}}]}

Answer 3

const group = {
$group: {
_id: { month: { $month: "$createdAt" } },
count: { $sum: 1 },
},
};
const groups = {
$group: {
_id: null,
patient: { $push: { month: '$_id.month', count: '$count' } },
},
};
return db.Patient.aggregate([group, groups]);