python连接mysql数据库

 

 

 例子：判断用户是否登录成功

 1 import pymysql
 2 import hashlib
 3 
 4 class Consql():
 5     def __init__(self):
 6         self.db = pymysql.connect(host='localhost', port=3306, user='root', password='mysql123', db='book')
 7         self.cursor = self.db.cursor()
 8 
 9     def close_sql(self):
10         self.cursor.close()
11         self.db.close()
12 
13     #增删改数据库
14     def operate_sql(self,sql):
15         self.cursor.execute(sql)
16         self.db.commit()
17 
18         self.close_sql()
19 
20     #查询数据库
21     def select_all_sql(self,sql):
22         self.cursor.execute(sql)
23         content =self.cursor.fetchall()
24 
25         self.close_sql()
26         return content
27 
28 if __name__ == '__main__':
29     con=Consql()
30     # #创建/修改表
31     # create_table='create table test_user(id int auto_increment primary key not null,name varchar(20),password char(35));'
32     # con.operate_sql(create_table)
33     # alter_sql='alter table test_user modify password char(32)'
34     # con.operate_sql(alter_sql)
35 
36 
37     # #插入数据
38     # insert_sql="insert into test_user(name,password) values('cherry','c7a4476fc64b75ead800da9ea2b7d072')"
39     # con.operate_sql(insert_sql)
40 
41     #判断用户是否存在及密码是否正确
42     user=input('请输入用户名:')
43     pwd=input('请输入密码:')
44     #将输入的密码加密
45     m=hashlib.md5()
46     m.update(pwd.encode('utf-8'))
47     s=m.hexdigest()
48     # print(s)
49 
50     select_sql='select password from test_user where name="{}";'.format(user)
51     result=con.select_all_sql(select_sql)
52     # print(result)
53 
54     if len(result)==0:
55         print('用户不存在')
56     elif result[0][0]==s:
57         print('登录成功')
58     else:
59         print('密码不正确')

 

posted on 2019-10-19 10:32  cherry_ning  阅读(132)  评论(0)    收藏  举报

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