Python 如何在PyMongo中获取_id名称列表
我想创建一个_id名称列表,例如Python 如何在PyMongo中获取_id名称列表,python,mongodb,python-2.7,pymongo,Python,Mongodb,Python 2.7,Pymongo,我想创建一个_id名称列表,例如['0','1','2','3','4','5','6','7','8','9'],PyMongo不在此查询中: > db.users.find({},{ "_id":1} ).limit(10) { "_id" : "0" } { "_id" : "1" } { "_id" : "2" } { "_id" : "3" } { "_id" : "4" } { "_id" : "5" } { "_id" : "6" } { "_id" : "7" } { "_
['0','1','2','3','4','5','6','7','8','9']
,PyMongo不在此查询中:
> db.users.find({},{ "_id":1} ).limit(10)
{ "_id" : "0" }
{ "_id" : "1" }
{ "_id" : "2" }
{ "_id" : "3" }
{ "_id" : "4" }
{ "_id" : "5" }
{ "_id" : "6" }
{ "_id" : "7" }
{ "_id" : "8" }
{ "_id" : "9" }
但是,以下代码不会产生任何结果:
from pymongo import MongoClient
if __name__ == '__main__':
db = MongoClient()
sDB = db.test.users
for u in list(sDB.users.find({}, {"_id": 1}).limit(10)):
print "!!!", u
为什么上面的列表是空的?您已经两次引用了
用户
,所以它实际上是在用户.用户
集合中查找的
这应该是可行的(您也不需要列表
调用):
db = MongoClient()
users = db.test.users
for u in users.find({}, {"_id": 1}).limit(10):
print "!!!", u