python操作数据库类。实现建表插入数据查询数据功能

Posted 2021-01-09 zz测试

 1 import mysql.connector
 2 class database:
 3     def __init__(self,ip,port,user,psw,dbname): 
 4              
 5         try:
 6             con=mysql.connector.connect(
 7                 host=ip,
 8                 user=user,
 9                 password=psw,
10                 port=port,
11                 database=dbname,
12                 charset=‘utf8‘,
13                 buffered=True
14             )
15             print(‘数据库连接成功‘)
16             self.con=con #con在其他类方法中还要多次调用，所以定义为成员变量
17             #cursor=con.cursor()
18         except mysql.connector.Error as e:
19             print(‘连接失败‘,str(e))
20         
21     def create_tb(self,sql):
22         try:
23             cursor=self.con.cursor()#获取游标  
24             cursor.execute(sql)#执行sql
25             print(‘创建成功‘)
26         except mysql.connector.Error as e:
27             print(‘创建失败‘,str(e))
28         finally:
29             cursor.close()#关闭游标
30 
31     def insert_tb(self,sql,data):
32         try:
33             cursor=self.con.cursor()  
34             cursor.executemany(sql,data)
35             self.con.commit()
36             print(‘数据插入成功‘)
37         except mysql.connector.Error as e:
38             self.con.rollback()
39             print(‘插入失败‘,str(e))
40         cursor.close()
41 
42     def select_tb(self,sql):
43         try:
44             cursor=self.con.cursor(dictionary=True)  
45             cursor.execute(sql)
46             result1=cursor.fetchall()
47             print(‘查询全部结果：‘,result1)
48         except mysql.connector.Error as e:
49             print(‘查询失败‘,str(e))
50         finally:
51             cursor.close()
52 
53     def select_tb_one(self,sql):
54         try:
55             cursor=self.con.cursor(dictionary=True)  
56             cursor.execute(sql)
57             result2=cursor.fetchone()
58             print(‘查询一条结果：‘,result2)
59         except mysql.connector.Error as e:
60             print(‘查询失败‘,str(e))
61         finally:
62             cursor.close()
63 
64     def select_tb_many(self,sql,count):
65         try:
66             cursor=self.con.cursor(dictionary=True)  
67             cursor.execute(sql)
68             result3=cursor.fetchmany(count)
69             print(‘查询结果：‘,result3)
70         except mysql.connector.Error as e:
71             print(‘查询失败‘,str(e))
72         finally:
73             cursor.close()

调用代码：

 1 #连接数据库
 2 db=database(‘127.0.0.1‘,‘3306‘,‘root‘,‘vertrigo‘,‘mysql‘)
 3 #创建表
 4 sql_create=‘create table student_5(id int(10) not null auto_increment, name varchar(10) default null, age int(3) default null, primary key (id))engine=myisam default charset=utf8;‘
 5 db.create_tb(sql_create)
 6 # #插入数据
 7 sql_insert=‘insert into student_5(id,name,age) values(%s,%s,%s)‘
 8 data_insert=[(1,‘guozhen‘,18),(2,‘ss‘,19),(3,‘alen‘,30)]
 9 db.insert_tb(sql_insert,data_insert)
10 #查询全部数据
11 sql_select=‘select * from student_5‘
12 db.select_tb(sql_select)
13 #查询多条数据
14 db.select_tb_many(sql_select,2)
15 #查询一条数据
16 db.select_tb_one(sql_select)
17 #关闭数据库连接
18 db.con.close()