智者创造机会,强者把握机会,弱者坐等机会。才能是来自独创性。独创性是思维观察明白和决定的一种独特的方式。
本文实例为大家分享了Python3连接MySQL模拟转账的具体实现代码,供大家参考,具体内容如下
# coding:utf8 import sys import pymysql class TransferMoney(object): def __init__(self,conn): self.conn=conn def check_acct_available(self,acctid): cursor = self.conn.cursor() try: sql="select * from account where acctid=%s" % acctid cursor.execute(sql) print ("check_acct_available:" + sql) rs = cursor.fetchall() if len(rs) ! = 1: raise Exception("账号%s不存在"% acctid) finally: cursor.close() def has_enough_money(self,acctid,money): cursor = self.conn.cursor() try: sql="select * from account where acctid=%s and money>%s" % (acctid,money) cursor.execute(sql) print ("has_enough_money:"+sql) rs = cursor.fetchall() if len(rs) ! = 1: raise Exception("账号%s余额不足"% acctid) finally: cursor.close() def reduce_money(self,acctid,money): cursor = self.conn.cursor() try: sql = "update account set money=money-%s where acctid=%s" % (money,acctid) cursor.execute(sql) print ("reduce_money:"+sql) if cursor.rowcount ! = 1: raise Exception("账号%s减款失败" % acctid) finally: cursor.close() def add_money(self,acctid,money): cursor = self.conn.cursor() try: sql="update account set money=money+%s where acctid=%s" % (money,acctid) cursor.execute(sql) print ("add_money:"+sql) if cursor.rowcount ! = 1: raise Exception("账号%s加款失败" % acctid) finally: cursor.close() def transfer(self,source_acctid,target_acctid,money): try: self.check_acct_available(source_acctid) self.check_acct_available(target_acctid) self.has_enough_money(source_acctid,money) self.reduce_money(source_acctid,money) self.add_money(target_acctid,money) self.conn.commit() except Exception as e: self.conn.rollback() raise e if __name__ == "__main__": source_acctid = sys.argv[1] target_acctid = sys.argv[2] money = sys.argv[3] conn = pymysql.Connect( host = 'localhost', unix_socket = "..mysql/mysql.sock", port = 3306, user = 'root', passwd = '', db = 'python_db', ) tr_money = TransferMoney(conn) try: tr_money.transfer(source_acctid,target_acctid,money) except Exception as e: print ("出现问题" + str(e)) finally: conn.close()
以上就是本文的全部内容,希望对大家学习python程序设计有所帮助。