问题
I am looking to find out the total documents count from aggregate join. is it possible to get count from the below code? if anybody have an idea please let me know.
db.collection("camp", function (err, camp) {
camp.aggregate([{$match: {status: {$ne: "Rejected"}}},
{'$lookup': {
from: "organization",
localField: "organization",
foreignField: "organizationId",
as: "orgnData"
}
}, {'$lookup': {
from: "organizer",
localField: "organizer",
foreignField: "organizerId",
as: "ornrData"
}},
{$unwind: "$orgnData"},
{$unwind: "$ornrData"},
{$match: {'ornrData.city': 'Nagpur'}},
{$skip: 0}, {$limit: 10},
{$sort: {id: -1}}
], function (err, info) {
res.json(info);
});
});
from above code i am looking to get total rows count of result before limit. if anybody have an idea please let me know?
回答1:
Add to the aggregate the following, removing limit:
{ $group: { _id: null, count: { $sum: 1 } } }
来源：https://stackoverflow.com/questions/36231528/how-to-get-count-from-aggregate-lookup-results