Question

我在mongo数据库中有这些数据，

{
    "_id": {
        "$oid": "5654a8f0d487dd1434571a6e"
    },
    "ValidationDate": {
        "$date": "2015-11-24T13:06:19.363Z"
    },
    "DataRaw": " WL 00100100012015-08-28 02:44:17+0000+ 16.81 8.879  1084.00",
    "ReadingsAreValid": true,
    "locationID": " WL 001",
    "Readings": {
        "pH": {
            "value": 8.879
        },
        "SensoreDate": {
            "value": {
                "$date": "2015-08-28T02:44:17.000Z"
            }
        },
        "temperature": {
            "value": 16.81
        },
        "Conductivity": {
            "value": 1084
        }
    },
    "HMAC": "ecb98d73fcb34ce2c5bbcc9c1265c8ca939f639d791a1de0f6275e2d0d71a801"
}

我的目标是计算过去30天内满足给定范围的温度，pH值和电导率值，但我收到的错误是我在网上搜索时无法解决的。这是我的代码。

import datetime
from pymongo import MongoClient


def total_data_push():
    data = MongoClient().cloudtest.test_5_27

    now = datetime.datetime.utcnow()
    last_30d = now - datetime.timedelta(days=30)
    last_year = now.replace(year=now.year - 1)

    since_last_month = data.find({"ReadingsAreValid": False}, {"ValidationDate": {"$gte": last_30d}},
        {"Readings.temperature.value": {"$gt": 1.0}}).count()

    print since_last_month

def main():
    total_data_push()

if __name__ == "__main__":
    main()

当我在没有ValidationDate片段的情况下运行脚本时，它会返回正确的值，但添加此数据组件以获取最近30天的值会返回以下错误

traceback (most recent call last):
  File "total_data_push.py", line 29, in <module>
    main()
  File "total_data_push.py", line 26, in main
    total_data_push()
  File "total_data_push.py", line 17, in total_data_push
    {"Readings.temperature.value": {"$gt": 1.0}}).count()
  File "/Library/Python/2.7/site-packages/pymongo/collection.py", line 866, in find
    return Cursor(self, *args, **kwargs)
  File "/Library/Python/2.7/site-packages/pymongo/cursor.py", line 90, in __init__
    raise TypeError("skip must be an instance of int")
TypeError: skip must be an instance of int

我在这里真正缺少什么？感谢您的帮助

Answer 1

正如@BenCr所说，如果你看find signature：

find（filter = None，projection = None，skip = 0，limit = 0， no_cursor_timeout = False，cursor_type = CursorType.NON_TAILABLE， sort = None，allow_partial_results = False，oplog_replay = False， modifiers = None，manipulate = True）

filter是第一个参数，如下所示：

since_last_month = db.data.find({
    "ReadingsAreValid": False,
    "ValidationDate": {"$gte": last_30d},
    "Readings.temperature.value": {"$gte": 1.0}
    }).count()

Answer 2

这个过滤器应该是：

since_last_month = db.data.find({
"ReadingsAreValid": False,
"ValidationDate": {"$gte": last_30d},
"Readings.temperature.value": {"$gte": 1.0}
}).count()

MongoDB过去30天的数据

2 个答案: