These states occur for the Event Scheduler thread, threads that are created to execute scheduled events, or threads that terminate the scheduler.
- The scheduler thread or a thread that was executing an event is terminating and is about to end. 
- The scheduler thread or a thread that executes an event has been initialized. 
- The scheduler has a nonempty event queue but the next activation is in the future. 
- The thread issued - SET GLOBAL event_scheduler=OFFand is waiting for the scheduler to stop.
- The scheduler's event queue is empty and it is sleeping.