Triggers are generally executed on some events, primarily on inserting/deleting/updating tables or records.
Something must first fire an event to the trigger to be executed.
You can use a job scheduler to execute an action at a given time.
Here is an article how to schedule jobs in MySql 5.1:
Joined: Jan 19, 2010
Thanks for help.
There can be any number of such records to check for schedule match, and if it checks every few seconds then I want to know , would it affect the performance?