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
| 1 | pip3 install pymysql |
二、使用操作
1、执行SQL
| 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
| 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
| 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
| 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：
| 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
| 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
| 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：
| 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：
| 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
| 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。
| 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。
| 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 ; |
| 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
| 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
| 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。
