python操作mongodb之基础操作

#coding：utf-8
__author__ = 'hdfs'
import pymongo
from pymongo import MongoClient
client = MongoClient()

client=MongoClient('10.0.0.9',27017)
#连接mongodb数据库
client = MongoClient('mongodb://10.0.0.9:27017/')
#指定数据库名称
db = client.test_database
#获取非系统的集合
db.collection_names(include_system_collections=False)
#获取集合名
posts = db.posts
#查找单个文档
posts.find_one()
#给定条件的一个文档
posts.find_one({"author": "Mike"})
#使用ID查找需要ObjectID
from bson.objectid import ObjectId
post_id='5728aaa96795e21b91c1aaf0'
document = client.db.collection.find_one({'_id': ObjectId(post_id)})
import datetime
new_posts = [{"author": "Mike",
             "text": "Another post!",
             "tags": ["bulk", "insert"],
             "date": datetime.datetime(2009, 11, 12, 11, 14)},
            {"author": "Eliot",
             "title": "MongoDB is fun",
             "text": "and pretty easy too!",
             "date": datetime.datetime(2009, 11, 10, 10, 45)}]
#插入多条记录
result = posts.insert_many(new_posts)
#返回插入的ID
result.inserted_ids
#递归集合
for post in posts.find():
    post

#递归条件集合
for post in posts.find({"author": "Mike"}):
    post

#文档的记录数
posts.count()

#区间查询
d = datetime.datetime(2009, 11, 12, 12)
for post in posts.find({"date": {"$lt": d}}).sort("author"):
    print post
#给集合profiles建立索引 唯一索引
result = db.profiles.create_index([('user_id', pymongo.ASCENDING)],unique=True)
#查看索引信息
list(db.profiles.index_information())
#
user_profiles = [
{'user_id': 211, 'name': 'Luke'},
{'user_id': 212, 'name': 'Ziltoid'}]
result = db.profiles.insert_many(user_profiles)

#聚合查询
from pymongo import MongoClient
db = MongoClient('mongodb://10.0.0.9:27017/').aggregation_example
#准备数据
result = db.things.insert_many([{"x": 1, "tags": ["dog", "cat"]},
                              {"x": 2, "tags": ["cat"]},
                             {"x": 2, "tags": ["mouse", "cat", "dog"]},
                               {"x": 3, "tags": []}])
result.inserted_ids
'''
{ "_id" : ObjectId("576aaa973e5269020848cc7c"), "x" : 1, "tags" : [ "dog", "cat" ] }
{ "_id" : ObjectId("576aaa973e5269020848cc7d"), "x" : 2, "tags" : [ "cat" ] }
{ "_id" : ObjectId("576aaa973e5269020848cc7e"), "x" : 2, "tags" : [ "mouse", "cat", "dog" ] }
{ "_id" : ObjectId("576aaa973e5269020848cc7f"), "x" : 3, "tags" : [ ] }
'''
from bson.son import SON
#$unwind 解开-后面的变量
pipeline = [
     {"$unwind": "$tags"},
     {"$group": {"_id": "$tags", "count": {"$sum": 1}}},
     {"$sort": SON([("count", -1), ("_id", -1)])}
 ]
list(db.things.aggregate(pipeline))
#使用聚合函数with command
db.command('aggregate', 'things', pipeline=pipeline, explain=True)