Mongo 查询以从子文档数组中获取重复条目

Question

这里的objective是根据条件查找子文档中的重复记录，return输出如下

数据集

[{

    _id: "objectId",
    name: "product_a",
    array: [{
        _id: "objectId",
        start: "2022-01-01 00:00:00.000Z",
        end: "2022-01-30 00:00:00.000Z",
        status: "active",
        person: "A" //reference objectId
    },
    {
        _id: "objectId",
        start: "2022-03-01 00:00:00.000Z",
        end: null,
        status: "active",
        person: "A"
    },
    {
        _id: "objectId",
        start: "2022-03-01 00:00:00.000Z",
        end: null,
        status: "active",
        person: "A"
    },
    {
        _id: "objectId",
        start: "2022-02-01 00:00:00.000Z",
        end: null,
        status: "active",
        person: "B"
    }]
},
{

    _id: "objectId",
    name: "product_b",
    array: [{
        _id: "objectId",
        start: "2021-12-30 00:00:00.000Z",
        end: "2022-01-30 00:00:00.000Z",
        status: "active",
        person: "C"
    },
    {
        _id: "objectId",
        start: "2022-03-01 00:00:00.000Z",
        end: null,
        status: "active",
        person: "C"
    },
    {
        _id: "objectId",
        start: "2022-03-01 00:00:00.000Z",
        end: null,
        status: "active",
        person: "C"
    },
    {
        _id: "objectId",
        start: "2022-03-20 00:00:00.000Z",
        end: null,
        status: "active",
        person: "D"
    }]
}]

预期输出

[
    {
        _id: "objectId",
        name: "product_a",
        targetIds: ["A"]
    },
    {
        _id: "objectId",
        name: "product_b",
        targetIds: ["C"]
    }
]

我正在尝试从每个文档中获取重复的人值作为数组 (targetIds)，其中该人在子文档中有两个活动记录，结尾为 null。以下是我试过的查询

connectCollection.aggregate([
    {
        $unwind: "$array"
    },
    {
        "$match": {
            $and: [
                {
                    "array.status": {
                        "$exists": true,
                        "$eq": "active"
                    }
                },
                {
                    "array.end": {
                        "$exists": true,
                        "$eq": null
                    }
                }
            ]
        }
    },
    {
        $group: {
            _id: {
                product_id: "$_id",
                product_name: "$name",
                targetIds: "$array.person"
            },
            count: {
                $sum: 1
            }
        }
    },
    {
        $match: {
            count: {
                $gt: 1
            }
        }
    },
    { $sort: { _id: 1 } }
])

Answer 1

你只差最后一步：

{
    $group: {
      _id: "$_id.product_id",
      name: {
        $first: "$_id.product_name"
      },
      targetIds: {
        $push: "$_id.targetIds"
      }
    }
  }

并将示例数据的第二个数组从 user 更改为 person，如您的查询（和@Yong Shun）所述。您可以看到它可以工作 here 输入数据中的一些小变化，以演示解决方案

Mongo 查询以从子文档数组中获取重复条目

Mongo Query to get duplicate entry from sub document array

mongodb

mongodb-query

aggregation-framework