ORDER BY date and time BEFORE GROUP BY name in mysql

Question

i have a table like this:

name    date         time
tom | 2011-07-04 | 01:09:52
tom | 2011-07-04 | 01:09:52
mad | 2011-07-04 | 02:10:53
mad | 2009-06-03 | 00         


        

Answer 1

This worked for me:

SELECT *
FROM your_table
WHERE id IN (
    SELECT MAX(id)
    FROM your_table
    GROUP BY name
);

Answer 2

In Oracle, This work for me

SELECT name, min(date), min(time)
    FROM table_name
GROUP BY name

Answer 3

As I am not allowed to comment on user1908688's answer, here a hint for MariaDB users:

SELECT *
FROM (
     SELECT *
     ORDER BY date ASC, time ASC
     LIMIT 18446744073709551615
     ) AS sub
GROUP BY sub.name

https://mariadb.com/kb/en/mariadb/why-is-order-by-in-a-from-subquery-ignored/

Answer 4

Another method:

SELECT * 
FROM (
    SELECT * FROM table_name
    ORDER BY date ASC, time ASC 
) AS sub
GROUP BY name

GROUP BY groups on the first matching result it hits. If that first matching hit happens to be the one you want then everything should work as expected.

I prefer this method as the subquery makes logical sense rather than peppering it with other conditions.