查看event是否啟用：
SELECT @@event_scheduler;
SHOW VARIABLES LIKE 'event%';
如果是為：OFF首装，則用下面代碼開啟定時
set GLOBAL event_scheduler = 1;
SET GLOBAL event_scheduler = ON;
這里編寫要定時的語句，DO 后面，就是執(zhí)行的代碼，這里是每1分鐘執(zhí)行一次
CREATE event IF NOT EXISTS temp_event ON SCHEDULE EVERY 1 MINUTE?
ON COMPLETION PRESERVE?
DO update allcolor set cgreen=cgreen+1 where id=1;
