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【轉】Python中操作mysql的pymysql模塊詳解

定義 padding 參數化查詢 finall 支持 順序 執行sql mysq syntax

Python中操作mysql的pymysql模塊詳解

前言

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而後者不支持3.x版本。

本文測試python版本:2.7.11。mysql版本:5.6.24

一、安裝

1 pip3 install pymysql

二、使用操作

1、執行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 # 創建連接 conn = pymysql.connect(host=‘127.0.0.1‘, port=3306, user=‘root‘, passwd=‘, db=‘tkq1‘, charset=‘utf8‘) # 創建遊標 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() # 關閉遊標 cursor.close() # 關閉連接 conn.close()

註意: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

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") # 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,也就是最後插入的一條數據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() #獲取自增id new_id = cursor.lastrowid print new_id

4、移動遊標

操作都是靠遊標,那對遊標的控制也是必須的

1 2 3 4 註:在fetch數據時按照順序進行,可以使用cursor.scroll(num,mode)來移動遊標位置,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:

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‘) #遊標設置為字典類型 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

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‘) #遊標設置為字典類型 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

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)) #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防註入

1、字符串拼接查詢,造成註入

正常查詢語句:

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()

構造註入語句:

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) #拼接語句被構造成下面這樣,永真條件,此時就註入成功了。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、避免註入,使用pymysql提供的參數化語句

正常參數化查詢

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" #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()

構造註入,參數化查詢註入失敗。

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" #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,避免註入語句生成。 # 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註入漏洞。

3、使用存mysql儲過程動態執行SQL防註入

使用MYSQL存儲過程自動提供防註入,動態傳入SQL到存儲過程執行語句。

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<?‘; 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 ;
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中調用

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

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 #定義上下文管理器,連接後自動關閉連接 @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

【轉】Python中操作mysql的pymysql模塊詳解