python 基础 9.11 更改数据

#/usr/bin/python

#-*- coding:utf-8 -*-

#@Time   :2017/11/24 4:45

#@Auther :liuzhenchuan

#@File   :更改数据.py

 

import MySQLdb

 

# 把分数小于5分的成绩都加6分

sql = '''select *, (grade+60) as new_grade from score where grade < 5;'''

update_sql = '''update score set grade = grade + 60 where grade <5;'''

 

def connect_mysql():

    db_config = {

        "host": "192.168.16.70",

        "port": 3306,

        "user": "root",

        "passwd": "123123",

        "db": "students",

        "charset": "utf8"

    }

    try:

        cnx = MySQLdb.connect(**db_config)

    except Exception as e:

        raise e

    return cnx

 

if __name__ == "__main__":

    cnx = connect_mysql()

    cus = cnx.cursor()

    try:

        cus.execute(sql)

        result1 = cus.fetchall()

        print(result1)

        cus.execute(update_sql)

        cus.execute(sql)

        result2 = cus.fetchall()

        print(result2)

        cus.close()

        cnx.commit()

    except Exception as e:

        cnx.rollback()

        raise e

    finally:

        cnx.close()