Using left join with min - mysql

Question

I am trying to connect two tables with left join and a date.
My SQL Query
SELECT
ord.`ordernumber` bestellnummer,
his.`change_date` zahldatum
FROM
`s_order` ord
LEFT JOIN
`s_order_history` his ON ((ord.`id`=his.`orderID`) AND (ord.`cleared`=his.`payment_status_id`)) #AND MIN(his.`change_date`)
WHERE
ord.`ordertime` >= \''.$dateSTART.'\' AND ord.`ordertime` <= \''.$dateSTOP.'\'' ;
s_order
+----+---------------------+---------+-------------+
| id | ordertime | cleared | ordernumber |
+----+---------------------+---------+-------------+
| 1 | 2014-08-11 19:53:43 | 2 | 123 |
| 2 | 2014-08-15 18:33:34 | 2 | 125 |
+----+---------------------+---------+-------------+
s_order_history
+----+-------------------+-----------------+---------+---------------------+
| id | payment_status_id | order_status_id | orderID | orderID change_date |
+----+-------------------+-----------------+---------+---------------------+
| 1 | 1 | 5 | 1 | 2014-08-11 20:53:43 |
| 2 | 2 | 5 | 1 | 2014-08-11 22:53:43 |
| 3 | 2 | 7 | 1 | 2014-08-12 19:53:43 |
| 4 | 1 | 5 | 2 | 2014-08-15 18:33:34 |
| 5 | 1 | 6 | 2 | 2014-08-16 18:33:34 |
| 6 | 2 | 6 | 2 | 2014-08-17 18:33:34 |
+----+-------------------+-----------------+---------+---------------------+
Wanted result:
+-------------+---------------------+
| ordernumber | change_date |
+-------------+---------------------+
| 123 | 2014-08-11 22:53:43 |
| 125 | 2014-08-17 18:33:34 |
+-------------+---------------------+
The problem I have is getting only the date, where the cleared/payment_status_id value has been changed in s_order. I currently get all dates where the payment_status_id matches the current cleared value, but I only need the one, where it happend first.
This is only an excerpt of the actually query, since the original is a lot longer (mostly more left joins and a lot more tables).

Answer 1

You can group data by ordernumber
SELECT
ord.`ordernumber` bestellnummer,
MIN(his.`min_change_date`) as zahldatum
FROM
`s_order` ord
LEFT JOIN
`s_order_history` his ON ((ord.`id`=his.`orderID`) AND (ord.`cleared`=his.`payment_status_id`)) #AND MIN(his.`change_date`)
WHERE
ord.`ordertime` >= \''.$dateSTART.'\' AND ord.`ordertime` <= \''.$dateSTOP.'\''
GROUP BY
ord.`ordernumber`;
or you can group data in a subquery:
SELECT
ord.`ordernumber` bestellnummer,
his.`min_change_date` zahldatum
FROM
`s_order` ord
LEFT JOIN (
SELECT
orderID, payment_status_id, MIN(change_date) as min_change_date
FROM
s_order_history
GROUP BY
orderID, payment_status_id
) his ON (ord.`id` = his.`orderID` AND ord.`cleared` = his.`payment_status_id`)
WHERE
ord.`ordertime` >= \''.$dateSTART.'\' AND ord.`ordertime` <= \''.$dateSTOP.'\'';

Answer 2

Try this:
select s_order.ordernumber, min(s_order_history.change_date)
from s_order left join s_order_history
on s_order.id = s_order_history.orderID
and s_order.cleared = s_order_history.payment_status_id
group by s_order.order_id

Answer 3

SELECT ord.`ordernumber` bestellnummer,
MIN( his.`change_date` ) zahldatum
...
GROUP BY ord.`ordernumber`

Answer 4

MIN is an aggregate function so you can't use it in a JOIN straight up like you've tried above. You also are not comparing it to a value in your JOIN.
You'll want to do something like:
his.`change_date` = (SELECT MIN(his.`change_date`) FROM s_order_history where ord.`id` = his.`orderID`)
in your JOIN.