Python学习入门（4）连接MySQL

下载MySQL for Python，最新版MySQL-python-1.2.4b4.tar.gz 1） 提前安装：mysql_config 环境 否则后面 python setup.py build 会提示找不到 “EnvironmentError: mysql_config not found”，安装命令如下： sudo apt-get install libmysqlclient-dev sudo a

下载 MySQL for Python，最新版 MySQL-python-1.2.4b4.tar.gz

1） 提前安装：mysql_config 环境

否则后面 python setup.py build 会提示找不到 “EnvironmentError: mysql_config not found”，安装命令如下：

sudo apt-get install libmysqlclient-dev

sudo apt-get install python-dev （解决fatal error: Python.h: No such file or directory）

CentOS 安装 yum install mysql-devel 和 yum install python-devel（解决error: command 'gcc' failed with exit status 1）

2） 然后，再安装MySQLdb

$ tar zxvf MySQL-python-1.2.2.tar.gz
$ cd MySQL-python-1.2.2
$ sudo python setup.py build
$ sudo python setup.py install

3） 验证成功安装

homer@ubuntu:~/myCode/python$ python
Python 2.7.3 (default, Aug 1 2012, 05:14:39)
[GCC 4.6.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import MySQLdb
>>>

import MySQLdb 没有出错，说明安装成功！

测试示例：

import MySQLdb
db = MySQLdb.connect("localhost","myusername","mypassword","mydb" )
cursor = db.cursor()
cursor.execute("SELECT VERSION()")
data = cursor.fetchone()    
print "Database version : %s " % data    
db.close()

python 连接mysql示例：

####################
# IT-Homer
# 2013-05-10
####################


import MySQLdb


db = MySQLdb.connect(host="localhost", user="root", passwd="abcd1234", db="testDB")

cursor = db.cursor()

cursor.execute("Select * from gameTestDB limit 10")
result = cursor.fetchall()

for row in result:
  #print row
  #print row[0], row[1], row[2]
  #print '%s, %s, %s' % (row[0], row[1], row[2])
  print ', '.join([str(row[0]), str(row[1]), str(row[2])])

cursor.close()



'''
import sys
import MySQLdb

reload(sys)
sys.setdefaultencoding('utf-8')


db = MySQLdb.connect(user='root', passwd='abcd1234', charset='utf8')
cur = db.cursor()
cur.execute('use testDB')
cur.execute('select * from gameTestDB limit 10')

f = file("/home/homer/tmp_mysql.txt", 'w')

for row in cur.fetchall():
  f.write(str(row))
  f.write("\n")

f.close()
cur.close()
'''

####################
# IT-Homer
# 2013-05-10
####################


import MySQLdb

# local mysql
# db = MySQLdb.connect(host="localhost", user="root", passwd="abcd1234", db="testDB")

# aws rds mysql
db = MySQLdb.connect(host="ithomer.aliyun.com", user="ithomer", passwd="abcd1234", db="dman")

cursor = db.cursor()

cursor.execute("Select * from score limit 10")
result = cursor.fetchall()

for row in result:
  #print row
  #print row[0], row[1], row[2]
  #print '%s, %s, %s' % (row[0], row[1], row[2])
  print ', '.join([str(row[0]), str(row[1]), str(row[2])])

cursor.close()



'''
import sys
import MySQLdb

reload(sys)
sys.setdefaultencoding('utf-8')


db = MySQLdb.connect(user='root', passwd='abcd1234', charset='utf8')
cur = db.cursor()
cur.execute('use testDB')
cur.execute('select * from gameTestDB limit 10')

f = file("/home/homer/tmp_mysql.txt", 'w')

for row in cur.fetchall():
  f.write(str(row))
  f.write("\n")

f.close()
cur.close()

python 连接mongodb

1） 安装pymongo

pymongo 下载，最新 pymongo-2.6.tar.gz

安装

$ tar zxvf pymongo-2.6.tar.gz
$ cd pymongo-2.6
$ sudo python setup.py build
$ sudo python setup.py install

2）连接mongodb

#!/usr/bin/python

import pymongo
import random

HOST = '172.27.22.21'
PORT = 27017

_DB='test'
_TABLE='testuser'


conn = pymongo.Connection("172.27.22.21", 27017)
db = conn[_DB]  # get db
db.authenticate("yanggang", "123456")

table = db[_TABLE]      # get collection
table.drop()
table.save({"id":1, "name":"homer", "age":18})

for id in range(2,10):
  name = random.choice(['it', 'homer', 'sunboy', 'yanggang'])
  age = random.choice([10, 20, 30, 40, 50, 60])

  table.insert({"id":id, "name":name, "age":age})

cursor = table.find()
for user in cursor:
  print user



'''
conn = pymongo.Connection("172.27.22.21", 27017)
db = conn.test
db.authenticate("yanggang", "123456")

db.testuser.drop()
db.testuser.save({"id":1, "name":"homer", "age":18})

for id in range(2,10):
  name = random.choice(['it', 'homer', 'sunboy', 'yanggang'])
  age = random.choice([10, 20, 30, 40, 50, 60])

  db.testuser.insert({"id":id, "name":name, "age":age})

cursor = db.testuser.find()
for user in cursor:
  print user
'''

运行结果

python 连接 Redis

1）前往 redis-py 下载发布版本 release，最新发布版本： redis-py-2.8.0.zip

2）解压 redis-py-2.8.0.zip： unzip redis-py-2.8.0.zip， 安装： sudo python setup.py install

3）验证安装成功：

# python
>>> import redis
>>>

4）简单示例：

>>> import redis
>>> r = redis.StrictRedis(host='localhost', port=6379, db=0)
>>> r.set('foo', 'bar')
True
>>> r.get('foo')
'bar'

#!/usr/bin/python
# -*- coding: utf-8 -*-

import sys
reload(sys)
sys.setdefaultencoding('utf-8')

import redis

_REDIS_HOST = '172.27.9.104'
_REDIS_PORT = 6379
_REDIS_DB = 0


def read_redis():
    r = redis.Redis(host=_REDIS_HOST, port=_REDIS_PORT, db=_REDIS_DB)

    # 删除当前数据库的所有数据
    r.flushdb()             

    r.set('foo', 'bar')
    print(r.get('foo'))         # bar

    r.set('blog', 'ithomer.net')
    r.set('name', 'yanggang')

    # 查询没有key，返回 None
    print(r.get('none123'))     # None

    # 库里有多少key，就多少条数据
    print(r.dbsize())           # 3

    # 列出所有键值
    print(r.keys())             # ['blog', 'foo', 'name']

if __name__ == "__main__":
    read_redis()

bar
None
3
['blog', 'foo', 'name']

参考推荐：

Python 連接 MySQL

MySQLdb User's Guide

Python 字符串操作

mysql_config not found（stackover flow）

python 创建mysql数据库

python连接mongodb并操作

redis-py（github）