问一个关于时间控制的典型有关问题
问一个关于时间控制的典型问题
业务关于一个抢先发言的问题，假设有1000个用户，5秒钟内抢先发言，且只能有一个人发言；5秒后谁也不能发言
由于客户要求，不能使用session
我是这样处理的
数据库中建立一个发言表tableWords，如果有第一个用户要抢先发言则，添加一条记录，之后其他的用户在抢发言，如果表中有记录，则不让发言；
这样做似乎没有问题，但考虑到并发的情况，很有可能1000个用户中有多个人在同一毫秒都执行了insert 操作，，如何只让一个用户insert了？
------解决方案--------------------
你的这个担忧是多余的
哪怕是同一微秒这1000个用户都发出了请求，在第一时刻也只有一个用户的请求被响应，其他的只是在排队
------解决方案--------------------
事务 文件锁 信号量锁等，用来判断用户发言资格
还可以依靠数据库唯一索引，字段可以由话题id？等指定，总之要唯一，显然这样就符合你的需求了
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