MySQL 8.0

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CREATE TABLE `oc_order` (
  `order_id` int(11) NOT NULL AUTO_INCREMENT,
  `order_status_id` int(11),
  PRIMARY KEY (`order_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

CREATE TABLE `oc_order_total` (
  `order_total_id` int(10) NOT NULL AUTO_INCREMENT,
  `order_id` int(11) NOT NULL,
  `code` varchar(32) NOT NULL,
  `title` varchar(255) NOT NULL,
  `text` varchar(255) NOT NULL,
  `value` decimal(15,4) NOT NULL DEFAULT '0.0000',
  `sort_order` int(3) NOT NULL,
  PRIMARY KEY (`order_total_id`),
  KEY `order_id` (`order_id`),
  KEY `code` (`code`),
  KEY `value` (`value`),
  KEY `order_id_code` (`order_id`,`code`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO `oc_order` (`order_id`, `order_status_id`)
VALUES
	(100053000, 1),
	(100053001, 1),
	(100054000, 1);

INSERT INTO `oc_order_total` (`order_total_id`, `order_id`, `code`, `title`, `text`, `value`, `sort_order`)
VALUES
	(1, 100053000, 'misc', 'Shipping Insurance', '$9.54', 9.5398, 4),
	(2, 100054000, 'misc', 'Shipping Insurance', '$2.91', 2.9051, 4);

order_id	insurance	order_id	max(insurance.value)	group_concat(insurance.order_id)
100053000	null	null	9.5398	100053000
100053001	9.5398	100053000	null	null
100054000	2.9051	100054000	2.9051	100054000