Python中操作mysql的pymysql模块详解

Python中操作mysql的pymysql模块详解

前言

pymsql是Python中操作MySQL的模块,其使用方法和MySQLdb几乎相同。但目前pymysql支持python3.x而后者不支持3.x版本。

本文测试python版本:2.7.11。mysql版本:5.6.24

一、安装

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pip3 install pymysql

二、使用操作

1、执行SQL

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#!/usr/bin/env pytho
# -*- coding:utf-8 -*-
import pymysql
  
# 创建连接
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1', charset='utf8')
# 创建游标
cursor = conn.cursor()
  
# 执行SQL,并返回收影响行数
effect_row = cursor.execute("select * from tb7")
  
# 执行SQL,并返回受影响行数
#effect_row = cursor.execute("update tb7 set pass = '123' where nid = %s", (11,))
  
# 执行SQL,并返回受影响行数,执行多次
#effect_row = cursor.executemany("insert into tb7(user,pass,licnese)values(%s,%s,%s)", [("u1","u1pass","11111"),("u2","u2pass","22222")])
  
  
# 提交,不然无法保存新建或者修改的数据
conn.commit()
  
# 关闭游标
cursor.close()
# 关闭连接
conn.close()

注意:存在中文的时候,连接需要添加charset='utf8',否则中文显示乱码。

2、获取查询数据

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#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"
import pymysql
 
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
cursor = conn.cursor()
cursor.execute("select * from tb7")
 
# 获取剩余结果的第一行数据
row_1 = cursor.fetchone()
print row_1
# 获取剩余结果前n行数据
# row_2 = cursor.fetchmany(3)
 
# 获取剩余结果所有数据
# row_3 = cursor.fetchall()
 
conn.commit()
cursor.close()
conn.close()

3、获取新创建数据自增ID

可以获取到最新自增的ID,也就是最后插入的一条数据ID

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#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"
import pymysql
 
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
cursor = conn.cursor()
effect_row = cursor.executemany("insert into tb7(user,pass,licnese)values(%s,%s,%s)", [("u3","u3pass","11113"),("u4","u4pass","22224")])
conn.commit()
cursor.close()
conn.close()
#获取自增id
new_id = cursor.lastrowid     
print new_id

4、移动游标

操作都是靠游标,那对游标的控制也是必须的

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注:在fetch数据时按照顺序进行,可以使用cursor.scroll(num,mode)来移动游标位置,如:
 
cursor.scroll(1,mode='relative') # 相对当前位置移动
cursor.scroll(2,mode='absolute') # 相对绝对位置移动

 

5、fetch数据类型

关于默认获取的数据是元祖类型,如果想要或者字典类型的数据,即:

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#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"
import pymysql
 
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
#游标设置为字典类型
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
cursor.execute("select * from tb7")
 
row_1 = cursor.fetchone()
print row_1  #{u'licnese': 213, u'user': '123', u'nid': 10, u'pass': '213'}
 
conn.commit()
cursor.close()
conn.close()

6、调用存储过程

a、调用无参存储过程

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#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"
 
import pymysql
 
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
#游标设置为字典类型
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
#无参数存储过程
cursor.callproc('p2'#等价于cursor.execute("call p2()")
 
row_1 = cursor.fetchone()
print row_1
 
 
conn.commit()
cursor.close()
conn.close()

b、调用有参存储过程

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#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"
 
import pymysql
 
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
 
cursor.callproc('p1', args=(1, 22, 3, 4))
#获取执行完存储的参数,参数@开头
cursor.execute("select @p1,@_p1_1,@_p1_2,@_p1_3"#{u'@_p1_1': 22, u'@p1': None, u'@_p1_2': 103, u'@_p1_3': 24}
row_1 = cursor.fetchone()
print row_1
 
 
conn.commit()
cursor.close()
conn.close()

三、关于pymysql防注入

 1、字符串拼接查询,造成注入

正常查询语句:

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#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"
import pymysql
 
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
cursor = conn.cursor()
user="u1"
passwd="u1pass"
#正常构造语句的情况
sql="select user,pass from tb7 where user='%s' and pass='%s'" % (user,passwd)
#sql=select user,pass from tb7 where user='u1' and pass='u1pass'
row_count=cursor.execute(sql) row_1 = cursor.fetchone()
print row_count,row_1
 
conn.commit()
cursor.close()
conn.close()

构造注入语句:

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#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"
import pymysql
 
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
cursor = conn.cursor()
 
user="u1' or '1'-- "
passwd="u1pass"
sql="select user,pass from tb7 where user='%s' and pass='%s'" % (user,passwd)
 
#拼接语句被构造成下面这样,永真条件,此时就注入成功了。因此要避免这种情况需使用pymysql提供的参数化查询。
#select user,pass from tb7 where user='u1' or '1'-- ' and pass='u1pass'
 
row_count=cursor.execute(sql)
row_1 = cursor.fetchone()
print row_count,row_1
 
 
conn.commit()
cursor.close()
conn.close()

 

 2、避免注入,使用pymysql提供的参数化语句

正常参数化查询

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#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"
 
import pymysql
 
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
cursor = conn.cursor()
user="u1"
passwd="u1pass"
#执行参数化查询
row_count=cursor.execute("select user,pass from tb7 where user=%s and pass=%s",(user,passwd))
row_1 = cursor.fetchone()
print row_count,row_1
 
conn.commit()
cursor.close()
conn.close()

构造注入,参数化查询注入失败。

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#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"
import pymysql
 
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
cursor = conn.cursor()
 
user="u1' or '1'-- "
passwd="u1pass"
#执行参数化查询
row_count=cursor.execute("select user,pass from tb7 where user=%s and pass=%s",(user,passwd))
#内部执行参数化生成的SQL语句,对特殊字符进行了加\转义,避免注入语句生成。
# sql=cursor.mogrify("select user,pass from tb7 where user=%s and pass=%s",(user,passwd))
# print sql
#select user,pass from tb7 where user='u1\' or \'1\'-- ' and pass='u1pass'被转义的语句。
 
row_1 = cursor.fetchone()
print row_count,row_1
 
conn.commit()
cursor.close()
conn.close()

结论:excute执行SQL语句的时候,必须使用参数化的方式,否则必然产生SQL注入漏洞。

3、使用存mysql储过程动态执行SQL防注入

使用MYSQL存储过程自动提供防注入,动态传入SQL到存储过程执行语句。

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delimiter \\
DROP PROCEDURE IF EXISTS proc_sql \\
CREATE PROCEDURE proc_sql (
  in nid1 INT,
  in nid2 INT,
  in callsql VARCHAR(255)
  )
BEGIN
  set @nid1 = nid1;
  set @nid2 = nid2;
  set @callsql = callsql;
    PREPARE myprod FROM @callsql;
--   PREPARE prod FROM 'select * from tb2 where nid>? and nid<?';  传入的值为字符串,?为占位符
--   用@p1,和@p2填充占位符
    EXECUTE myprod USING @nid1,@nid2;
  DEALLOCATE prepare myprod;
 
END\\
delimiter ;
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set @nid1=12;
set @nid2=15;
set @callsql = 'select * from tb7 where nid>? and nid<?';
CALL proc_sql(@nid1,@nid2,@callsql)

pymsql中调用

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#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"
import pymysql
 
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
cursor = conn.cursor()
mysql