How to update mysql data with event and remove the event after - mysql

Question

I have a mysql table that looks like this
| begintime | endtime | begindate | enddate | state |
+------------+----------+------------+----------+-------+
| TIME | TIME | DATE | DATE | string|
+------------+----------+------------+----------+-------+
I have this code
CREATE EVENT Update
ON SCHEDULE
EVERY 1 SECOND
DO
UPDATE tablename SET tablename.state = CASE
WHEN (SELECT CURRENT_TIME() FROM DUAL)>=tablename.begintime AND (SELECT CURDATE()>= tablename.begindate) THEN "Available"
WHEN (SELECT CURRENT_TIME() FROM DUAL)>tablename.endtime AND (SELECT CURDATE()= tablename.enddate) THEN "Finished"
ELSE "Not Available"
END
I want the server to be always checking if any of those statements is true, and I dont know how to remove the event when:
WHEN (SELECT CURRENT_TIME() FROM DUAL)>tablename.endtime AND (SELECT CURDATE()= tablename.enddate) THEN "Finished
Thanks for your help.

Answer 1

please try this one.
SET GLOBAL event_scheduler = ON;
DROP EVENT IF EXISTS Update1;
CREATE EVENT Update1
ON SCHEDULE
EVERY 1 SECOND
DO
UPDATE tablename SET tablename.state =
CASE
WHEN NOW() BETWEEN CONCAT(tablename.begindate,' ',tablename.begintime) AND CONCAT(tablename.enddate,' ',tablename.endtime) THEN "Available"
WHEN NOW() > CONCAT(tablename.enddate,' ',tablename.endtime) THEN "Finished"
ELSE "Not Available"
END;
To drop the event after setting to "Finished" try using something like this
SET GLOBAL event_scheduler = ON;
DROP EVENT IF EXISTS Update1;
DELIMITER //
CREATE EVENT Update1
ON SCHEDULE
EVERY 1 SECOND
DO BEGIN
SELECT #begindate := begindate,
#begintime:= begintime,
#enddate := enddate,
#endtime := endtime FROM tablename;
IF (NOW() BETWEEN CONCAT(#begindate,' ',#begintime) AND CONCAT(#enddate,' ',#endtime)) THEN
UPDATE tablename SET state = 'Available';
ELSEIF (NOW() < CONCAT(#begindate,' ',#begintime)) THEN
UPDATE tablename SET state = 'Not Available';
ELSEIF (NOW() > CONCAT(#enddate,' ',#endtime)) THEN
UPDATE tablename SET state = 'Finished';
DROP EVENT IF EXISTS Update1;
END IF;
END//
DELIMITER ;