如何从Mongodb集合中的时间（HH：MM：SS.Milisecond）值大于零的日期字段中选择记录，并通过保留日期值将其更新为时间（HH：MM：SS）值为零与python脚本中的相同。
当前数据如下所示 -
1) "createdDate" : ISODate("2015-10-10T00:00:00Z")
2) "createdDate" : ISODate("2015-10-11T00:00:00Z")
3) "createdDate" : ISODate("2015-10-12T00:00:00Z")
4) "createdDate" : ISODate("2015-10-13T01:04:30.515Z")
5) "createdDate" : ISODate("2015-10-14T02:05:50.516Z")
6) "createdDate" : ISODate("2015-10-15T03:06:60.517Z")
7) "createdDate" : ISODate("2015-10-16T04:07:80.518Z")
如何使用mongodbsql仅选择行4,5,6,7并在python脚本中将时间戳更新为零 -
更新后的数据如下所示 -
1) "createdDate" : ISODate("2015-10-10T00:00:00Z")
2) "createdDate" : ISODate("2015-10-11T00:00:00Z")
3) "createdDate" : ISODate("2015-10-12T00:00:00Z")
4) "createdDate" : ISODate("2015-10-13T00:00:00Z")
5) "createdDate" : ISODate("2015-10-14T00:00:00Z")
6) "createdDate" : ISODate("2015-10-15T00:00:00Z")
7) "createdDate" : ISODate("2015-10-16T00:00:00Z")
答案 0 :(得分：3)
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由PyMongo表示为ISODate()个对象。 MongoDB假定日期和时间是UTC。对于给定的UTC时间datetime，有几种方法可以获得午夜（一天的开始）：
d答案 1 :(得分：1)
更新文档的最佳方式和00:00:00时间createdDate正在使用set模块，因为from datetime import datetime
from pymongo import MongoClient
client = MongoClient()
db = client.test
collection = db.collection
bulkOp = collection.initialize_ordered_bulk_op()
count = 0
for doc in collection.find():
year = doc['createdDate'].year
month = doc['createdDate'].month
day = doc['createdDate'].day
new_date = datetime(year, month, day)
bulkOp.find({'_id': doc['_id']}).update({'$set': {'createdDate': new_date}})
count = count + 1
if count == 125:
bulkOp.execute()
bulkOp = collection.initialize_ordered_bulk_op()
if count % 125 != 0:
bulkOp.execute()
在python中是datetime所以你可以使用日期时间实例属性datetime object，day和year。
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