Python连接mysql数据库及简单增删改查操作示例代码

自学编程网 Python

2020-10-08 0 617

1.安装pymysql

进入cmd，输入 pip install pymysql:

2.数据库建表

在数据库中，建立一个简单的表，如图：

3.简单操作

3.1查询操作

#coding=utf-8
#连接数据库测试
import pymysql
#打开数据库
db = pymysql.connect(host=\"localhost\",user=\"root\",password=\"root\",db=\"test\")
#使用cursor()方法获取操作游标
cur = db.cursor()
#查询操作
sql = \"select * from books\"
try:
 # 执行sql语句
 cur.execute(sql) 
 results = cur.fetchall()
 #遍历结果
 for rows in results:
  id = rows[0]
  name = rows[1]
  price = rows[2]
  bookcount = rows[3]
  author = rows[4]
  print(\"id: {}, name: {}, price: {}, bookcount: {}, author: {}\".format(id,name,price,bookcount,author))
except Exception as e:
 raise e
finally:
 db.close()

运行结果：

3.2插入操作

#coding=utf-8
#插入操作
import pymysql
db = pymysql.connect(host=\"localhost\",user=\"root\",password=\"root\",db=\"test\")
cur = db.cursor()
sql = \"\"\"insert into books(id,bookname,price,bookCount,author) values (4,\'三体\',20,3,\'刘慈欣\')\"\"\"
try:
 cur.execute(sql)
 #提交
 db.commit()
except Exception as e:
 #错误回滚
 db.rollback()
finally:
 db.close()

运行结果：

3.3更新操作

#coding=utf-8
#更新操作
import pymysql
db = pymysql.connect(host=\"localhost\",user=\"root\",password=\"root\",db=\"test\")
# 使用cursor()方法获取游标
cur = db.cursor()
sql_update = \"update books set bookname = \'%s\',author = \'%s\' where id = %d\"
try:
 cur.execute(sql_update % (\"边城\",\"沈从文\",4))
 #提交
 db.commit()
except Exception as e:
 #错误回滚
 db.rollback()
finally:
 db.close()

运行结果：

3.4删除操作

#coding=utf-8
#删除操作
import pymysql
db = pymysql.connect(host=\"localhost\",user=\"root\",password=\"root\",db=\"test\")
#使用cursor()获取操作游标
cur = db.cursor()
sql_delete = \"delete from books where id = %d\"
try:
 #向sql语句传递参数
 cur.execute(sql_delete % (1))
 #提交
 db.commit()
except Exception as e:
 #错误回滚
 db.rollback()
finally:
 db.close()

运行结果：