相关疑难解决方法(0)

在mongodb中有以下结构的文档:

{
    "_id" : ObjectId("52d017d4b60fb046cdaf4851"),
    "dates" : [
        1399518702000,
        1399126333000,
        1399209192000,
        1399027545000
    ],
    "dress_number" : "4",
    "name" : "J. Evans",
    "numbers" : [
        "5982",
        "5983",
        "5984",
        "5985"
    ]
}

是否可以从多个数组中展开数据并仅从数组中获取成对元素:

{
    "dates": "1399518702000",
    "numbers": "5982"
},
{
    "dates": "1399126333000",
    "numbers": "5983"
},
{
    "dates": "1399209192000",
    "numbers": "5984"
},
{
    "dates": "1399027545000",
    "numbers": "5985"
}

有聚合管道:

db.getCollection('yourCollection').aggregate(
    {
        $unwind: {
            path: "$dates",
            includeArrayIndex: "idx"
        }
    },
    {
        $project: {
            _id: 0,
            dates: 1,
            numbers: { $arrayElemAt: ["$numbers", "$idx"] },
            goals: { $arrayElemAt: ["$goals", "$idx"] },
            durations: { $arrayElemAt: ["$durations", "$idx"] }
        }
    }
)

执行以下数据(示例文档):

{
    "_id" : ObjectId("52d017d4b60fb046cdaf4851"),
    "dates" : [
        1399518702000,
        1399126333000,
        1399209192000,
        1399027545000
    ],
    "dress_number" : "4",
    "name" : "J. Evans",
    "numbers" : [
        "5982",
        "5983",
        "5984",
        "5985"
    ],
    "goals": [
        "1",
        "0",
        "4",
        "2"
    ],
   "durations": [
       "78",
       "45",
       "90",
       "90" …