沧海一粟

#!/usr/bin/python
# -*- coding:utf8 -*-

import pymysql

#取得数据库连接对象
conn = pymysql.connect(host=‘127.0.0.1‘,port=3306,user=‘root‘,passwd=‘1234‘,db=‘python‘)
#取得游标对象
cur = conn.cursor()

#插入数据
cur.execute("INSERT INTO student(name,sex,age) VALUES(‘3‘, ‘0‘, ‘45‘)")
conn.commit()
#修改数据
cur.execute("UPDATE student SET age = 90 WHERE id = 2" )
conn.commit()
#删除数据
cur.execute("DELETE FROM student WHERE name = ‘3‘")
conn.commit()

###########################################
#    数据发生改变时一定要conn.commit()    #
###########################################

#查询数据
cur.execute(‘SELECT *FROM student‘)
for r in cur.fetchall():
    print(r)

cur.close()
conn.close()

# wget "https://pypi.python.org/packages/source/p/pip/pip-1.5.4.tar.gz#md5=834b2904f92d46aaa333267fb1c922bb" --no-check-certificate

# tar -xzvf pip-1.5.4.tar.gz
# cd pip-1.5.4
# python setup.py install

# pip install SomePackage
  [...]
  Successfully installed SomePackage

# pip show --files SomePackage
  Name: SomePackage
  Version: 1.0
  Location: /my/env/lib/pythonx.x/site-packages
  Files:
   ../somepackage/__init__.py
   [...]

# pip list --outdated
  SomePackage (Current: 1.0 Latest: 2.0)

# pip install --upgrade SomePackage
  [...]
  Found existing installation: SomePackage 1.0
  Uninstalling SomePackage:
    Successfully uninstalled SomePackage
  Running setup.py install for SomePackage
  Successfully installed SomePackage

$ pip uninstall SomePackage
  Uninstalling SomePackage:
    /my/env/lib/pythonx.x/site-packages/somepackage
  Proceed (y/n)? y
  Successfully uninstalled SomePackage

# pip install redis

# pip uninstall redis
Uninstalling redis:
  /usr/lib/python2.6/site-packages/redis-2.9.1-py2.6.egg-info
.....省略一些内容....
Proceed (y/n)? y
  Successfully uninstalled redis

pip list --outdate
pygpgme (Current: 0.1 Latest: 0.3)
pycurl (Current: 7.19.0 Latest: 7.19.3.1)
iniparse (Current: 0.3.1 Latest: 0.4)

# pip --help

Usage:  
  pip <command> [options]

Commands:
  install                     安装包.
  uninstall                   卸载包.
  freeze                      按着一定格式输出已安装包列表
  list                        列出已安装包.
  show                        显示包详细信息.
  search                      搜索包，类似yum里的search.
  wheel                       Build wheels from your requirements.
  zip                         不推荐. Zip individual packages.
  unzip                       不推荐. Unzip individual packages.
  bundle                      不推荐. Create pybundles.
  help                        当前帮助.

General Options:
  -h, --help                  显示帮助.
  -v, --verbose               更多的输出，最多可以使用3次
  -V, --version               现实版本信息然后退出.
  -q, --quiet                 最少的输出.
  --log-file <path>           覆盖的方式记录verbose错误日志，默认文件：/root/.pip/pip.log
  --log <path>                不覆盖记录verbose输出的日志.
  --proxy <proxy>             Specify a proxy in the form [user:passwd@]proxy.server:port.
  --timeout <sec>             连接超时时间 (默认15秒).
  --exists-action <action>    Default action when a path already exists: (s)witch, (i)gnore, (w)ipe, (b)ackup.
  --cert <path>               证书.

update friend set cname=cname+'wang' where id=1.

CONCAT(str1,str2,...)

update friend set cname=CONCAT(cname,'.wang') where id=1

update friend set cname=CONCAT_WS('.',cname,'wang') where id=1,

du -s /home/* | sort -nr

find . -size +100000000c -exec ls -lh {} ;