Ask a typical question about time control.

Ask a typical question about time control business about a preemptive speech. suppose there are 1000 users who can speak first in five seconds, and only one person can speak; no one can speak in five seconds. due to customer requirements, the session cannot be used. in this case, I create a statement table tableWords in the database, if the first user asks a typical question about time control
For example, if 1000 users speak first within five seconds, and only one user can speak first, no one can speak in five seconds.
The session cannot be used due to customer requirements.

I handled it like this.
Create a statement table tableWords in the database. if the first user wants to speak first, add a record, and other users are scrambling to speak. if there is a record in the table, do not allow the user to speak;

This does not seem to be a problem, but considering the concurrency, it is very likely that many of the 1000 users performed the insert operation in the same millisecond. how can we only let one user insert?


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Your worries are superfluous.
Even if these 1000 users send requests in the same microsecond, only one user's request is responded at the first time. Others are only waiting in the queue.
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Transaction File lock semaphore lock, used to determine the user's qualification to speak


You can also rely on the unique index of the database. Can the field be determined by the topic id? And so on. In short, it must be unique. Obviously, this will meet your needs.