Mysql triggers PHP

The problem of triggering PHP in mysql is now needed. a fixed data entry in mysql database triggers a PHP program as soon as it changes. how can this problem be achieved? Thank you ~, The changes in the transition table can only be checked by writing related information to a transitional table in the mysql trigger. the changes can only be php round-robin, but the transition table is small and should not affect the PHP trigger problem in mysql.
The requirement is as follows,
A fixed data entry in the mysql database triggers a PHP program as long as it changes. how can this problem be achieved? Thank you ~

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Only related information can be written to a transitional table in the mysql trigger.
Check that the change in the transition table can only be php round-robin, but the transition table is small and should not be affected.
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Can I use the stored procedure written in C?
The idea is as follows:
1. trigger a stored procedure using the trigger mechanism;
2. the stored procedure calls a C-written stored procedure;
3. the stored procedure written in C calls the PHP script in CGI mode.
I have never tried it. it should be okay.
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If the round robin is less than one second, will the server explode?
I think it will be painful to consider the stress issue in the future, even if you have handled it before.
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This requirement is an incremental model. it is not suitable to use a database as the storage medium.

If the message is incrementing, you can directly append it to a file. you need to save the message number in a file and lock the message number file before the message file. the Message number is + 1, then, append the message to the message file and release the lock.

The client AJAX maintains the maximum message number for the last request.

Round robin is positive, HTTP is not really pushed, and AJAX is a persistent connection to the cloud.