学习笔记十

　　今天转战python了，学习了python如何使用pip导入库（pip install 库），并使用python连接了mysql数据库，对其进行了增删改查操作。

 1 import pymysql
 2 
 3 # 打开连接
 4 
 5 
 6 def open_conn(dbname):
 7     db = pymysql.connect(
 8         host="localhost",
 9         port=3306,
10         user="root",
11         passwd="密码",
12         db=dbname,
13         charset="utf8")
14 
15     return db
16 
17 # 遍历查询
18 
19 
20 def query(db):
21 
22     cursor = db.cursor()
23     sql = "select * from demo"
24     cursor.execute(sql)
25     for each in cursor.fetchall():
26         print(each)
27 
28 # 增加数据
29 
30 
31 def add(db):
32 
33     cursor = db.cursor()
34     sql = "insert into demo(name,sex,phone) values('小张','男','1234567')"
35     cursor.execute(sql)
36     db.commit()
37     # 查看插入后的结果
38     sql = "select * from demo where name ='小张'"
39     cursor.execute(sql)
40     for each in cursor.fetchall():
41         print(each)
42 
43 # 修改数据
44 
45 
46 def update(db):
47     cursor = db.cursor()
48     sql = " update demo set sex='女' where name='小张'"
49     cursor.execute(sql)
50     db.commit()
51     # 查看更新后的结果
52     sql = "select * from demo where name='小张'"
53     cursor.execute(sql)
54     for each in cursor.fetchall():
55         print(each)
56 
57 
58 # 删除数据
59 
60 def delete(db):
61     cursor = db.cursor()
62     sql = " delete from demo where name='小张'"
63     cursor.execute(sql)
64     db.commit()
65     # 查看更新后的结果
66     sql = "select * from demo where name='小张'"
67     cursor.execute(sql)
68     for each in cursor.fetchall():
69         print(each)
70 
71 
72 if __name__ == '__main__':
73     # query(open_conn("dbname"))
74     # add(open_conn("dbname"))
75     # update(open_conn("dbname"))
76     # delete(open_conn("dbname"))
77     pass

增删改查

　　以下为效果截图：

　　增添操作：

　　修改操作：

　　遍历查询操作：

　　删除操作：