install pip:
sudo apt-get install python3-pip
upgrading pip:
pip install -U pip(on linux or macos)
python -m pip install -U pip(on windows)
install pymongo:
sudo pip install pymongo
sudo apt-get install mongodb
mkdir /data/db
start mongodb:./bin/mongod --dbpath=/data/db
start mongodb daemon:
mkdir /log
mongod --dbpath=/data/db/ --fork --logpath=/log/mongodb.log
or
mkdir /opt/mongodb/conf.d/mongodb.conf
vim /opt/mongodb/conf.d/mongodb.conf
and paste bellow:
port=27017
dbpath=/data/db
logpath=/log/mongodb.log
logappend=true
fork=true
mongod -c /opt/mongodb/conf.d/mongodb.conf
connect.py
import pymongo
from pymongo import *
get database connection
client = MongoClient()
the same way
client = MongoClient("localhost",27017)
client = MongoClient("mongodb://localhost:27017/")
assign database and collection to operat
db = client.test_db
collection = db.test_collection
IDUS
insert
mydict = {"name": "cursor", "sex": "female", "job": "dev"}
collection.insert(mydict)
collection.insert_one(mydict)
mylist = []
mylist.append(mydict)
insert_many param must be list
collection.insert_many(mylist)
find
find_one() just show meet the conditions first collection
find() return all the object array which meet the conditions
collection.find({"name": "cursor"})[0]
collection.find({"name": "cursor"})[1]
use for-in operation to loop all
for i in collection.find({"name": "cursor"}):
print(i)
search assign conditions
collection.find_one({"name": "cursor"})
collection.find_one({"name": "cursor", "sex": "female"})
use .count()
collection.find().count() # this is equal to collection.count()
collection.find({"name": "cursor"}).count()
条件查询 $lt(<) $gt(>) $lte(<=) $gte(>=) #ne(!=)
collection.find({"age": {"$lt": 30}})
sort the find result
collection.find().sort("age") # defult ASC
collection.find().sort("age", pymongo.ASCENDING)
collection.find().sort("age", pymongo.DESCENDING)
查询 database中所有collection
db.collection_names()
db.collection_names(include_system_collections=False) # 不包括系统collection，一般指的是system.indexes
update
temp = collection.find_one({"name": "Lucy"})
temp2 = temp.copy()
temp["name"] = "Jordan"
如果此时temp[“_id”]在该collection中已经存在，则.save()为更新操作，与 .replace_one() 作用相同，否则 .save() 为插入操作，与 .insert_one() 作用相同。
collection.save(temp) # 或 .update() ，注意参数形式
collection.update(temp, temp2) # 将temp更新为temp2
还要注意的一点是，.replace_one()需要传入两个参数，分别为当前document和要更新为的 document ，与 .update() 相同
collection.replace_one(old_document, new_document)
delete
collection.remove(temp) # 即便该temp不存在也不会报错
collection.delete_one(temp)
collection.delete_many(temp) # 与 .insert_many() 不同，在temp不是list类型时也不会报错
JSON序列化与反序列化
import json
如果想序列化为标准 JSON 格式，两种方式，方式一，json 包中的 dumps：
for i in collection.find({"name": "cursor"}):
del i["_id"] # 不能直接转换，无法识别ObjectId
json.dumps(i)
bson.json_util包中封装的 dumps：
from bson import Binary, Code
from bson.json_util import dumps
dumps([{'foo': [1, 2]},
{'bar': {'hello': 'world'}},
{'code': Code("function x() { return1; }")},
{'bin': Binary("")}])
