python操作mysql之pymysql

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

本文測試python版本：2.7.11。mysql版本：5.6.24

一、安裝

pip3 install pymysql

 

二、使用操作

1、執行SQL

#!/usr/bin/env pytho
# -*- coding:utf-8 -*-
import pymysql
  
# 創建連接
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1', charset='utf8')
# 創建游標
cursor = conn.cursor()
  
# 執行SQL，並返回收影響行數
effect_row = cursor.execute("select * from tb7")
  
# 執行SQL，並返回受影響行數
#effect_row = cursor.execute("update tb7 set pass = '123' where nid = %s", (11,))
  
# 執行SQL，並返回受影響行數,執行多次
#effect_row = cursor.executemany("insert into tb7(user,pass,licnese)values(%s,%s,%s)", [("u1","u1pass","11111"),("u2","u2pass","22222")])
  
  
# 提交，不然無法保存新建或者修改的數據
conn.commit()
  
# 關閉游標
cursor.close()
# 關閉連接
conn.close()

注意：存在中文的時候，連接需要添加charset='utf8'，否則中文顯示亂碼。

2、獲取查詢數據

#! /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")

# 獲取剩余結果的第一行數據
row_1 = cursor.fetchone()
print row_1
# 獲取剩余結果前n行數據
# row_2 = cursor.fetchmany(3)

# 獲取剩余結果所有數據
# row_3 = cursor.fetchall()

conn.commit()
cursor.close()
conn.close()

3、獲取新創建數據自增ID

可以獲取到最新自增的ID，也就是最后插入的一條數據ID

#! /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()
#獲取自增id
new_id = cursor.lastrowid           
print new_id

 

 

4、移動游標

操作都是靠游標，那對游標的控制也是必須的

注：在fetch數據時按照順序進行，可以使用cursor.scroll(num,mode)來移動游標位置，如：

cursor.scroll(1,mode='relative')  # 相對當前位置移動
cursor.scroll(2,mode='absolute')  # 相對絕對位置移動

 

5、fetch數據類型

　　關於默認獲取的數據是元祖類型，如果想要或者字典類型的數據，即：

#! /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')
#游標設置為字典類型
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、調用存儲過程

a、調用無參存儲過程

#! /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')
#游標設置為字典類型
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
#無參數存儲過程
cursor.callproc('p2')    #等價於cursor.execute("call p2()")

row_1 = cursor.fetchone()
print row_1


conn.commit()
cursor.close()
conn.close()

b、調用有參存儲過程

#! /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))
#獲取執行完存儲的參數,參數@開頭
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、關於pymysql防注入

 1、字符串拼接查詢，造成注入

正常查詢語句：

#! /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"
#正常構造語句的情況
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()

 

構造注入語句：

#! /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)

#拼接語句被構造成下面這樣，永真條件，此時就注入成功了。因此要避免這種情況需使用pymysql提供的參數化查詢。
#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提供的參數化語句

正常參數化查詢

#! /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"
#執行參數化查詢
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() 

構造注入，參數化查詢注入失敗。

#! /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"
#執行參數化查詢
row_count=cursor.execute("select user,pass from tb7 where user=%s and pass=%s",(user,passwd))
#內部執行參數化生成的SQL語句，對特殊字符進行了加\轉義，避免注入語句生成。
# 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'被轉義的語句。

row_1 = cursor.fetchone()
print row_count,row_1

conn.commit()
cursor.close()
conn.close()

 

 結論：excute執行SQL語句的時候，必須使用參數化的方式，否則必然產生SQL注入漏洞。

3、使用存mysql儲過程動態執行SQL防注入

使用MYSQL存儲過程自動提供防注入，動態傳入SQL到存儲過程執行語句。

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<?';    傳入的值為字符串，？為占位符
--     用@p1，和@p2填充占位符
        EXECUTE myprod USING @nid1,@nid2;
    DEALLOCATE prepare myprod; 

END\\
delimiter ;

 

set @nid1=12;
set @nid2=15;
set @callsql = 'select * from tb7 where nid>? and nid<?';
CALL proc_sql(@nid1,@nid2,@callsql)

 

pymsql中調用 

#! /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簡化連接過程

每次都連接關閉很麻煩，使用上下文管理，簡化連接過程

#! /usr/bin/env python
# -*- coding:utf-8 -*-
# __author__ = "TKQ"

import pymysql
import contextlib
#定義上下文管理器，連接后自動關閉連接
@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()

# 執行sql
with mysql() as cursor:
   print(cursor)
   row_count = cursor.execute("select * from tb7")
   row_1 = cursor.fetchone()
   print row_count, row_1