Question

我想获取python3 pymongo由“名称”建立的“数据”项目中的每个“ ecg_raw”。

如果我知道'name'和'time_info'，我如何获取4个ecg_raw数据，其中time_info =='2018-09-01 00:00:03'

我想获取每个[[8,2]，[1,10]，[9,4]，[1,9]]之类的ecg_raw数据

我尝试了

db.g.find({"data":{"$elemMatch":{"time_info":"2018-09-01 00:00:03"}}},{"name":1,"data":{"$elemMatch":{"time_info":"2018-09-01 00:00:03"}}})

但它只返回一个值，如bottom。

{'_id': ObjectId('5b90d401219e9c9f72cac8c4'), 'name': 'testDog3', 'data': [{'time_info': '2018-09-01 00:00:03', 'ecg_raw': [8, 2]}]}

请帮助我。

> db.g.find().pretty()
{
"_id" : ObjectId("5b90d401219e9c9f72cac8c4"),
"name" : "testDog3",
"data" : [
    {
        "time_info" : "2018-09-01 00:00:03",
        "ecg_raw" : [
            8,
            2
        ]
    },
    {
        "time_info" : "2018-09-01 00:00:03",
        "ecg_raw" : [
            1,
            10
        ]
    },
    {
        "time_info" : "2018-09-01 00:00:03",
        "ecg_raw" : [
            9,
            4
        ]
    },
    {
        "time_info" : "2018-09-01 00:00:03",
        "ecg_raw" : [
            1,
            9
        ]
    },
    {
        "time_info" : "2018-09-01 00:00:04",
        "ecg_raw" : [
            10,
            6
        ]
    },
    {
        "time_info" : "2018-09-01 00:00:04",
        "ecg_raw" : [
            1,
            6
        ]
    }
]
}

Answer 1

尝试一下。

aggregate（[{$ match：{'name'：'testDog3'}}，{“ $ unwind”：“ $ data”}，{“ $ match”：{“ data.time_info”：“ 2018-09 -01 00:00:03“}}]）

pymongo：如何从mongodb中提交多个结果？

1 个答案: