表TABLE:
ID DATE MSG
001 20080801 11
001 20080802 22
002 20080803 33要得到结果:(取ID相同的时间最大的MSG)
001 22
002 33这个SQL怎么写???
ID DATE MSG
001 20080801 11
001 20080802 22
002 20080803 33要得到结果:(取ID相同的时间最大的MSG)
001 22
002 33这个SQL怎么写???
SELECT * FROM tb a
WHERE NOT EXISTS (SELECT 1 FROM tb WHERE ID=a.ID AND MSG>a.MSG )
from [table]
group by id
from tb a
where not exists(select 1 from tb where ID=a.ID and DATE>a.DATE)