mysql - how to delete records with condition - mysql

Question

Here is my table structure:
CREATE TABLE `order`
(`order_id` int, `order_status_id` int, `ip` varchar(11), `date_added` datetime)
;
INSERT INTO `order`
(`order_id`, `order_status_id`, `ip`, `date_added`)
VALUES
(1, 0, '192.168.1.1', '2016-12-07 00:00:00'),
(2, 0, '192.168.1.1', '2016-12-07 00:00:00'),
(3, 0, '192.168.1.1', '2016-12-07 00:00:00'),
(4, 0, '192.168.1.1', '2016-12-07 00:00:00'),
(5, 1, '192.168.1.1', '2016-12-07 00:00:00'),
(6, 0, '192.168.1.2', '2016-12-08 00:00:00'),
(7, 0, '192.168.1.2', '2016-12-08 00:00:00'),
(8, 0, '192.168.1.2', '2016-12-08 00:00:00'),
(9, 0, '192.168.1.2', '2016-12-08 00:00:00'),
(10, 1, '192.168.1.2', '2016-12-08 00:00:00'),
(11, 0, '192.168.1.3', '2016-12-09 00:00:00'),
(12, 0, '192.168.1.3', '2016-12-09 00:00:00'),
(13, 0, '192.168.1.3', '2016-12-09 00:00:00'),
(14, 0, '192.168.1.3', '2016-12-09 00:00:00'),
(15, 0, '192.168.1.3', '2016-12-09 00:00:00');
http://sqlfiddle.com/#!9/20c0f
I expect sql erase all records except records where order_id are: 5, 10, 15
Explanations: I would like to erase records which has order_status_id = 0 with conditions:
a) if one of the record (from same ip/date_added order_id) has order_status_id = 1, then erase all records which has order_status_id = 0 (from same ip/date_added). In my example records 1-4 and 6-9 should be deleted.
b) if there are no record from same ip/date_added with order_id = 1 (all records has order_status_id = 0), then leave one record with the highest order_id (all other deleted). In my example records 11-14 should be deleted.

Answer 1

SQL DEMO
First you need separate your condition. You have {ip,date} with order_status_id {0,1}
-- first filter
SELECT `ip`, `date_added`
FROM `order`
GROUP BY `ip`, `date_added`
HAVING MAX(`order_status_id`) = 1;
-- second filter
SELECT `ip`, `date_added`
FROM `order`
GROUP BY `ip`, `date_added`
HAVING MAX(`order_status_id`) = 0;
First delete
You delete everyone matching the first filter but only those with order_status_id = 0 meaning you left the one with 1
DELETE o
FROM `order` o
INNER JOIN (
SELECT `ip`, `date_added`
FROM `order`
GROUP BY `ip`, `date_added`
HAVING MAX(`order_status_id`) = 1
) filter
ON o.`ip` = filter.`ip`
AND o.`date_added` = filter.`date_added`
WHERE o.`order_status_id` = 0;
Second delete
You delete everyone matching second filter, but leave the one who doesnt have any id higher than him.
DELETE o1
FROM `order` o1
INNER JOIN (
SELECT `ip`, `date_added`
FROM `order`
GROUP BY `ip`, `date_added`
HAVING MAX(`order_status_id`) = 0
) filter
ON o1.`ip` = filter.`ip`
AND o1.`date_added` = filter.`date_added`
LEFT JOIN `order` o2
ON o1.`order_id` < o2.`order_id`
WHERE o2.`ip` IS NOT NULL;
OUTPUT