python -【mongo】 處理Ob
- 2020 年 1 月 7 日
- 筆記
ObjectID簡介
mongo存儲的數據在沒有特別指定_id數據類型時，默認類型為ObjectID 『_id』: ObjectId(『55717c9eb2c983c127000000』)
ObjectId is a 12-byte BSON type, constructed using:
- a 4-byte value representing the seconds since the Unix epoch,
- a 3-byte machine identifier,
- a 2-byte process id, and
- a 3-byte counter, starting with a random value.
python處理方式
基本思路就是轉換成時間對象 ,然後處理.
objectid – Tools for working with MongoDB ObjectIds Tools for working with MongoDB ObjectIds. class bson.objectid.ObjectId(oid=None) Initialize a new ObjectId.
- 從ObjectID生成時間對象
from bson.objectid import ObjectId a = ObjectId('55717c9eb2c983c127000000') a.generation_time.timetuple() In [29]: a.generation_time.timetuple() Out[29]: time.struct_time(tm_year=2015, tm_mon=6, tm_mday=5, tm_hour=10, tm_min=40, tm_sec=30, tm_wday=4, tm_yday=156, tm_isdst=0) #到了這種格式就可以隨便處理了 In [30]: time.strftime("%Y-%m-%d %H:%M:%S",a.generation_time.timetuple()) Out[30]: '2015-06-05 10:40:30'- 生成ObjectID
# 時間對象轉換 >>> gen_time = datetime.datetime(2010, 1, 1) >>> dummy_id = ObjectId.from_datetime(gen_time) >>> ObjectId(b'foo-bar-quux') ObjectId('666f6f2d6261722d71757578') >>> ObjectId('0123456789ab0123456789ab') ObjectId('0123456789ab0123456789ab') >>> >>> # A u-prefixed unicode literal: >>> ObjectId(u'0123456789ab0123456789ab') ObjectId('0123456789ab0123456789ab')
