mysqldaterecords

Get only the records with most recent date to every code

I have a table like this

+------+-------+-----------+-------------+
| code | price | perct_off | date_review |
+------+-------+-----------+-------------+
| 0001 |  1500 |        40 | 2017-12-30  |
| 0001 |  1500 |        40 | 2018-02-15  |
| 0001 |  2000 |        25 | 2018-07-31  |
| 0002 |  3000 |        45 | 2018-03-20  |
| 0002 |  5000 |        20 | 2018-08-01  |
| 0003 |  3000 |        40 | 2018-01-16  |
+------+-------+-----------+-------------+

and I want to have only the records with the max date for every code. The iutput must be:

+------+-------+-----------+-------------+
| code | price | perct_off | date_review |
+------+-------+-----------+-------------+
| 0001 |  2000 |        25 | 2018-07-31  |
| 0002 |  5000 |        20 | 2018-08-01  |
| 0003 |  3000 |        40 | 2018-01-16  |
+------+-------+-----------+-------------+

When I try:

SELECT DISTINCT
    (code), price, perct_off, MAX(date_review)
FROM `table01`
GROUP BY code

I've got this output

+-------+--------+------------+-------------------+
| code  | price  | perct_off  | max(date_review)  |
+-------+--------+------------+-------------------+
| 0001  |   1500 |         40 | 2018-07-31        |
| 0002  |   3000 |         45 | 2018-08-01        |
| 0003  |   3000 |         40 | 2018-01-16        |
+-------+--------+------------+-------------------+

How can I get the rigth output?

Thanks in advance.

Solution

  • One canonical way to do this is to join to subquery which finds the most recent date for each code:

    SELECT t1.*
FROM table01 t1
INNER JOIN
(
    SELECT code, MAX(date_review) AS max_date_review
    FROM table01
    GROUP BY code
) t2
    ON t1.code = t2.code AND t1.date_review = t2.max_date_review;