Ask a typical question about time control

Ask a typical question about time control
Business on the question of a preemptive statement, assume that there are 1000 users, 5 seconds to be the first to speak, and only one person can speak; after 5 seconds, no one can speak.
Cannot use session due to customer requirements

That's what I'm dealing with.
Set up a statement in the database tablewords, if there is a first user to be early to speak, add a record, and then other users in the robbery to speak, if the table has records, then do not allow to speak;

This does not seem to be a problem, but given the concurrency situation, it is likely that more than 1000 users have performed the insert operation in the same millisecond, how do I only have one user insert?


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This worry of yours is superfluous.
Even in the same microsecond these 1000 users have made a request, and only one user's request was answered at the first moment, and the others were just queued
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Transaction file lock signal volume lock, etc., used to determine the user's speaking eligibility


Can also rely on the database unique index, the field can be by topic ID? And so on, so to be unique, obviously it fits your needs.

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