Python中MongoDB使用

MongoDB的层级为 database -->collection --> document

安装MongoDB，启动mongo服务

PyMongo模块是Python对MongoDB操作的接口包，主要实现对MongoDB的几种操作：增删改查以及排序等功能

安装Python的mongo模块

pip install pymongo

安装完后查看

pip list

模块引用

import pymongo

建立连接

import pymongo
from pymongo import MongoClient
client = MongoClient('localhost',27017)
#client = MongoClient('mongodb://localhost:27017')

访问数据库

当前所使用的数据库test的users

db = client.test
users = db.users
#或者db = client['users']

插入文档

文档就是一行，集合就是一个表

一个insert_one()

user1 = {"name":"li8","age":8}
rs = users.insert_one(user1)
print('one insert:{0}'.format(rs.inserted_id))

多个 insert_many()

user2 = {"name":"li9","age":9}
user3 = {"name":"li10","age":10}
user4 = {"name":"li11","age":11}
user5 = {"name":"li12","age":12}
new_result = users.insert_many([user2, user3, user4, user5])
print('Multiple users: {0}'.format(new_result.inserted_ids))

检索文档

一个find_one()

usertmp = users.find_one({"age":33})
print(usertmp)

多个find()

rs = users.find({'age': 33})
for tmp in rs:
    print(tmp)

高级查询

rs = users.find({'age':{"$lt":30}}).sort("name")
for tmp in rs:
    print(tmp)

统计数量

print(users.count())

加索引

from pymongo import ASCENDING, DESCENDING
print(users.create_index([("age", DESCENDING), ("name", ASCENDING)]))

 数据导出

mongoexport -d test -c users --csv -f name,age  -o e:pythonusers.csv