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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1 pip3 install pymysql

二、使用操作

1、执行SQL

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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 #!/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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 #! /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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 #! /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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1 2 3 4 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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 #! /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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 #! /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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 #! /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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 #! /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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 #! /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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 #! /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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 #! /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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 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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1 2 3 4 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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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 #! /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 = "select * from tb7 where nid>? and nid<?" cursor.callproc( 'proc_sql' , args = ( 11 , 15 , mysql))   rows = cursor.fetchall() print rows #((12, 'u1', 'u1pass', 11111), (13, 'u2', 'u2pass', 22222), (14, 'u3', 'u3pass', 11113)) conn.commit() cursor.close() conn.close()

四、使用with简化连接过程

每次都连接关闭很麻烦,使用上下文管理,简化连接过程

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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 #! /usr/bin/env python # -*- coding:utf-8 -*- # __author__ = "TKQ"   import pymysql import contextlib #定义上下文管理器,连接后自动关闭连接 @contextlib .contextmanager def mysql(host = '127.0.0.1' , port = 3306 , user = 'root' , passwd = ' ', db=' tkq1 ',charset=' utf8'):    conn = pymysql.connect(host = host, port = port, user = user, passwd = passwd, db = db, charset = charset)    cursor = conn.cursor(cursor = pymysql.cursors.DictCursor)    try :      yield cursor    finally :      conn.commit()      cursor.close()      conn.close()   # 执行sql with mysql() as cursor:    print (cursor)    row_count = cursor.execute( "select * from tb7" )    row_1 = cursor.fetchone()    print row_count, row_1

总结

以上就是关于Python中pymysql模块的全部内容,希望对大家学习或使用python能有一定的帮助,如果有疑问大家可以留言交流。

    原文作者:sql
    原文地址: https://www.cnblogs.com/wt11/p/6141225.html
    本文转自网络文章,转载此文章仅为分享知识,如有侵权,请联系博主进行删除。
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