Multiple aggregates in the same query - mongodb

Question

I have a problem that I dont know how to solve it with MongoDB syntax.
In fact, this is my actual query :
db.traitement".aggregate {$match: {timestampentre: {$gt: start}, timestampentre: {$lt: end}}}, {$project: {year: {$year: "$date_entre"}, month: {$month: "$date_entre"}, "carnetsanitairedone.isDoneDouche": "$carnetsanitairedone.isDoneDouche", "carnetsanitairedone.isDoneDetartrage": "$carnetsanitairedone.isDoneDetartrage"}}, {$group: {_id: {year: "$year", month: "$month", "carnetsanitairedone.isDoneDouche": "$carnetsanitairedone.isDoneDouche", "carnetsanitairedone.isDoneDetartrage": "$carnetsanitairedone.isDoneDetartrage"}, count: {$sum: 1}}}
that returns me this resultset :
[ { _id:
{ year: 2014,
month: 10,
'carnetsanitairedone.isDoneDouche': false,
'carnetsanitairedone.isDoneDetartrage': false },
count: 1 },
{ _id:
{ year: 2014,
month: 10,
'carnetsanitairedone.isDoneDouche': true,
'carnetsanitairedone.isDoneDetartrage': true },
count: 1 },
{ _id:
{ year: 1970,
month: 1,
'carnetsanitairedone.isDoneDouche': false,
'carnetsanitairedone.isDoneDetartrage': false },
count: 1 },
{ _id:
{ year: 1970,
month: 1,
'carnetsanitairedone.isDoneDouche': true,
'carnetsanitairedone.isDoneDetartrage': true },
count: 2 } ]
What I really need corresponds to the following resultset :
'year': 2014,
'month': 10,
'count.isDoneDouche': 10,
'count.isNotDoneDouche': 20,
'count.isDoneDetartrage': 30,
'count.isNotDoneDetartrage': 13
Can you help me with this request ?
Thanks for advance

Answer 1

You can conditionally $sum items with the use of the $cond operator for any key that you supply as an _id value:
db.traitement.aggregate([
{ "$match": {
"timestampentre": { "$gt": start, "$lt": end}
}},
{ "$group": {
"_id": {
"year": { "$year": "$date_entre" },
"month": { "$month": "$date_entre" }
},
"countIsDoneDouche": {
"$sum": {
"$cond": [
"$carnetsanitairedone.isDoneDouche",
1,
0
]
}
},
"countIsNotDoneDouche": {
"$sum": {
"$cond": [
{ "$ne": [ "$carnetsanitairedone.isDoneDouche", true ] },
1,
0
]
}
},
"countIsDoneDetartrage": {
"$sum": {
"$cond": [
"$carnetsanitairedone.isDoneDetartrage",
1,
0
]
}
},
"countIsNotDoneDetartrage": {
"$sum": {
"$cond": [
{ "$ne": [ "$carnetsanitairedone.isDoneDetartrage", true ] }
1,
0
]
}
}
}}
])
This allows the conditions of the supplied "ternary" in each $cond operation to determine whether the "counter" is incremented for the current value or not.