Pymongo Library Simple Application (Python's MongoDB library) __python

Simple application of Pymongo library

The Pymongo library is a library of Python operations MongoDB. The following is a brief introduction to the simple use of Pymongo. Create MONGO client Select database and set merge insert Data

Import Pymongo

client = Pymongo. Mongoclient (host,port)
#client = Pymongo. Mongoclient (' mongodb://localhost:27017/')

db = Client.db #选择名称叫db的数据库, no
#或者db = client[' db '

will be created Collection = Db.test #选择test名的collection, no
#或者collection = db[' Test ' is created

#collection can manipulate
the collection Collection.insert ({' name ': ' AAA '}} #返回插入id
Collection.insert ([{' Name ': ' aaa '},{' name ': ' BBB '}]) #返回插入id的list
e = collection.insert_one ({' Name ': ' CCC '}) #返回结果通过e. inserted_id View Insert id

obj =  {' A ': ' B '}
Collection.insert_one (obj)
#插入成功后obj会多一个属性_id
print (obj) #{' _id ': ObjectId (' 58cf7eaac43b3761209924be ') , ' A ': ' B '
#insert也会产生相同的效果 to add an additional _id attribute to the inserted element to represent the ID after inserting the database

connection with certified MONGO

The above connection can connect MONGO that do not set a password, but MONGO with a password requires a different way of connecting.

#SCRAM-sha-1 way
uri = "Mongodb://user:password@example.com/the_database?authmechanism=scram-sha-1"
Client = Mongoclient (URI)

#或者
client = mongoclient (' example.com ')
client.the_database.authenticate (' User ', ' Password ', mechanism= ' scram-sha-1 ')

#MONGODB-cr Way from
Pymongo import mongoclient
uri = "Mongodb://user: PASSWORD@EXAMPLE.COM/THE_DATABASE?AUTHMECHANISM=MONGODB-CR "
client = mongoclient (URI)

#或者
client = Mongoclient (' example.com ')
client.the_database.authenticate (' user ', ' password ', mechanism= ' MONGODB-CR ')

#或者使用默认加密方式
uri = "Mongodb://user:password@example.com/the_database"
client = mongoclient (URI)

Querying Data

A = Collection.find ({' name ': ' AAA '}) #返回游标, you can get
a = Collection.find_one ({' name ': ' AAA '}) for an iteration or A.next () #返回结果
' {'
_id ': ObjectId (' 58b92cdfc43b3735664597be '), ' name ': ' AAA '} '
#如果id是字符串类型的 from
Bson.objectid import Objectid #导入ObjectId把字符串id转换成ObjectId才能查找
collection.find_one ({' _id ': Objectid (' 58b93904c43b3735664597c2 ')})
#直接使用字符串id是无法查询到内容的

#查看数据条数
collection.count ()
#或者 Collection.find (). Count ()
collection.find ({"Name": "AAA"}). Count ()

#条件查询和排序
d = datetime.datetime ( 2009, one,
collection.find ({"date": {"$lt": D}}). Sort ("author")
#限制查询条数和指定位置开始查询
Collection.find ({"date": {"$lt": D}}). Skip (1) #跳过符合条件的前一条, back to
collection.find (...). Limit (5) #查询5条结果
collection.find (...). Skip (5). Limit (5) #跳过前5条返回后面的5条
#排序
collection.find (...). Sort (' username ', Pymongo. Descending) #使用username排序DESCENDING为倒序, ascending positive sequence, (ascending=1,descending=-1)
#多条件排序
Collection.find (...). Sort (' username ', Pymongo. Descending), (' id ', Pymongo. Ascending))

Update

Import Pymongo
client = Pymongo. Mongclient (' 127.0.0.1 ')
db = client.test
collection = Db.user
collection.update ({' A ': ' B '}, {' $set ': {' a ') : ' B '}}; #update (condition, {' $set ': Update value})

Remove

result = Collection.delete_many ({' A ': ' B '}) #delete_many (condition)
result.delete_count  #删除个数 Result
= Collection.delete_one ({' A ': ' B '}) #delete_one (condition)
result.delete_count  #删除个数

Create an index

Create an index to speed up queries

Collection.create_index ([' user_id ', Pymongo. Ascending),], unique=true
#创建一个唯一的不可重复的索引user_id, multiple indexes can be created at a time

Refer to official documentation
Http://api.mongodb.com/python/current/tutorial.html

Note:
Use ORM Access MONGO use Mongoengine package
Document Http://docs.mongoengine.org