# -*- coding: UTF-8 -*-import mysql.connectorclassTransferMoney():

def __init__(self, db):

self.db=db

#转账流程

def transferMoney(self, id, targetId, money):try:

self.checkTargetUser(targetId) #检查被转账账号是否存在

self.checkMoney(id, money) #检查余额是否足够

self.transfer(id, targetId, money) #转账

self.db.commit() #提交修改

except Exceptionase:

self.db.rollback() #回滚事物

raise e

#检查被转账账号是否存在

def checkTargetUser(self, id):try:

cursor=self.db.cursor()

sql_query= 'select * from user where id=%s;' %id

cursor.execute(sql_query)

rs=cursor.fetchall()if len(rs) != 1:

raise Exception('转账账户不存在！')else:

print'转账账户存在!'except mysql.connector.Errorase:

raise Exception('检查被转账账户是否存在出错：' +str(e))finally:

cursor.close()

#检查转账金额

def checkMoney(self, id, money):try:

cursor=self.db.cursor()

sql_query= 'select * from user where id=%s and money > %s;' %(id,money)

cursor.execute(sql_query)

rs=cursor.fetchall()if len(rs) != 1:

raise Exception('转账账户余额不足！')else:

print'转账方金额充足!'except mysql.connector.Errorase:

raise Exception('检查金额出错：：' +str(e))finally:

cursor.close()

#转账

def transfer(self, id, targetId, money):try:

cursor=self.db.cursor()

#自己先减去转账金额

sql_query= 'update user set money=money-%s where id=%s;' %(money,id)

rs=cursor.execute(sql_query)if cursor.rowcount != 1:

raise Exception('账号%s减款失败！' %id)

#目标账户加上转账金额

sql_query1= 'update user set money=money+%s where id=%s;' %(money, targetId)

cursor.execute(sql_query1)if cursor.rowcount != 1:

raise Exception('账号%s加款失败！' %targetId)

print'成功转账%s元！' %money

except mysql.connector.Errorase:

raise Exception('转账出错：' +str(e))finally:

cursor.close()if __name__ == '__main__':

db= mysql.connector.connect(host='127.0.0.1',port=3306,user='root',passwd='gou110422',database='test',charset='utf8')base =TransferMoney(db)try:

id,targetId,money= (1,2,100)base.transferMoney(id, targetId, money)

except Exceptionase:

print'异常：',efinally:

db.close()

#cursor.execute执行sql 语句

#cursor.rowcount 表中受影响数据个数 放在execute()之后

#fetchall() 获取所有数据

#fetchone() 获取一条数据

#fetchmany(3) 获取 3个数据

#db.commit() 数据表内容有更新，必须使用到该语句#cursor.close() #关闭游标