从 where 子句中的列中获取最大值

Question

I have table:

id date  day
2  21-07 1
2  10-07 3
2  11-07 2

I need to get date which has highest day , in current example it should be 10-07. Next query works fine, but is there way to make it more optimised?

SELECT date
      FROM (SELECT date, MAX(day)
            FROM some_table 
            WHERE id = 2
            GROUP BY date
        LIMIT 1) x

Answer 1

I would not suggest a where clause. Just use:

select date
from some_table
where id = 2
order by day desc
limit 1;