ey_datetime 추가

[Taebu]

update `ez_youtubelink` b,(select 
concat("20",SUBSTRING(ey_title, 1, 2),'-',SUBSTRING(ey_title, 3, 2),'-',SUBSTRING(ey_title, 5, 2),' ',IF(SUBSTRING(ey_title, 10, 2)="후","16","11"),":00:00") ey_date,
ey_datetime,
ey_title  
from `ez_youtubelink` 
where ey_group='lecture_01'
 and ey_title like '1%'
 order by ey_datetime desc) as a  SET 
b.ey_datetime=a.ey_date  where b.ey_title=a.ey_title;