Python全栈 MongoDB 数据库（聚合、二进制、GridFS、pymongo模块）

from pymongo import MongoClient 

#创建连接
conn = MongoClient('localhost',27017)

#创建数据库对象
db = conn.stu 

#创建集合对象
myset = db.class4 

print(dir(myset))

# 插入操作
myset.insert({'name':'张铁林','King':'乾隆'})
myset.insert([{'name':'张国立','King':'康熙'},\
    {'name':'陈道明','King':'康熙'}])
myset.insert_many([{'name':'唐国强','King':'雍正'},\
    {'name':'陈建斌','King':'雍正'}])
myset.insert_one({'name':'郑少秋','King':'乾隆'})
myset.save({'_id':1,'name':'聂远','King':'乾隆'}) 

# 查找操作

cursor = myset.find({},{'_id':0})

# i为每个文档对应的字典
for i in cursor:
    print(i['name'],'--->',i['King'])

myset = db.class1 
# 操作符使用引号变为字符串
cursor = myset.find({'age':{'$gt':30}},{'_id':0})

cursor.limit(2)#获取前两个文档
cursor.skip(2) #跳过前两个
cursor.sort([('age',-1),('name',1)]) #对游标内容排序

for i in cursor:
    print(i)
print(cursor.next()) #获取下一个文档


dic = {'$or':[{'age':{'$gt':35}},{'gender':'w'}]}
data = myset.find_one(dic,{'_id':0})
print(data)

# 修改操作
myset.update({'name':'张国立'},\
    {'$set':{'king_name':'玄烨'}})

myset.update({'name':'霍建华'},{'$set':{'King':'乾隆'}},\
    upsert = True)

myset.update({'King':'乾隆'},\
    {'$set':{'king_name':'弘历'}},multi = True)

myset.update_one({'King':'康熙'},\
    {'$set':{'king_name':'爱新觉罗玄烨'}})

myset.update_many({'King':'雍正'},\
    {'$set':{'king_name':'胤禛'}})

# 删除操作

myset.remove({'King':'康熙'})
myset.remove({'King':'乾隆'},multi = False)

#查找并删除
print(myset.find_one_and_delete({'King':'乾隆'}))


#关闭连接
conn.close()

from pymongo import MongoClient 

#创建连接
conn = MongoClient('localhost',27017)

#创建数据库对象
db = conn['stu'] 

myset = db['class1'] 

# 删除所有索引
myset.drop_indexes()

# 创建索引
index = myset.ensure_index('name')
# 创建复合索引
index = myset.ensure_index([('name',-1),('age',1)])
print(index)

# 删除一个索引
myset.drop_index('name_1')

# 创建特殊索引
index = myset.ensure_index('name',name = "myIndex",\
    unique = True,sparse = True)

# 查看集合中的索引
for i in myset.list_indexes():
    print(i)

myset = db.class4 

l = [
    {'$group':{'_id':'$King','num':{'$sum':1}}},
    {'$match':{'num':{'$gt':1}}}
]

cursor = myset.aggregate(l)
for i in cursor:
    print(i)

conn.close()

from pymongo import MongoClient 
import bson.binary 

conn = MongoClient('localhost',27017)
db = conn.images 
myset = db.img 

#存储
f = open('file.jpg','rb')

#转换为mongodb的二进制数据存储形式
content = bson.binary.Binary(f.read())

#插入到数据库
myset.insert({'filename':'file.jpg','data':content})

#提取

data = myset.find_one({'filename':'file.jpg'})

#通过字典获取到数据库内容写入本地
with open(data['filename'],'wb') as f:
    f.write(data['data'])

conn.close()

from pymongo import MongoClient 
#pymongo绑定的模块
import gridfs

conn = MongoClient('localhost',27017)
db = conn.grid 

#获取gridfs对象
#fs综合了fs.files  fs.chunks两个集合的属性内容
fs = gridfs.GridFS(db)

#查文档生产游标
files = fs.find()

#获取每一个文件的对象
for file in files:
    print(file.filename)
    if file.filename == 'file.jpg':
        with open(file.filename,'wb') as f:
            #从数据库读取出来
            data = file.read()
            #写入本地
            f.write(data)

conn.close()