如何从汇总查找结果中获取计数 [英] How to get count from aggregate lookup results

问题描述

我正在寻找汇总联接中的文档总数.是否可以从下面的代码中获取计数?如果有人有主意，请告诉我.

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);
    });
});

从上面的代码

我希望得到限制前结果的总行数.如果有人有主意，请让我知道?

from above code i am looking to get total rows count of result before limit. if anybody have an idea please let me know?

推荐答案

将以下内容添加到集合中，以消除限制:

Add to the aggregate the following, removing limit:

{ $group: { _id: null, count: { $sum: 1 } } }

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