我是菜鸟,我要腾飞
mysql数据库,c#写的程序,c/s结构,
create table user
(
id varchar(10),
name varchar(20)
pass varchar(20)
islogin varchar(20)
)
insert into user
select '01','a1' 'a1' '1'
insert into user
select '02','a2''a2' '0'
得到user的内容如下例如
name pass islogin
a1 a1 1
a2 a2 0
现在我想写一个验证用户名密码的验证啊,当a1用户输入的name pass的内容都正确时修改islogin为1,islogin默认为0,表示用户已经登录,当再有相同的的用户名登录时禁止登录 。当用户退出时修改islogin的值为0。
------解决方案--------------------
完全是业务逻辑问题 不涉及到复杂的sql
------解决方案--------------------
你做到哪一步了,有什么问题
------解决方案--------------------
这个功能应该在你的LOGIN代码和LOGOUT代码中去实现。不是在数据库中实现的。
------解决方案--------------------
登录之前检测islogin为1时就不让登录,提示“此帐户已经登录了,请等待其退出”。

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