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CREATE TABLE IF NOT EXISTS `sales` (
`id` int(2) NOT NULL,
`date` varchar(50),
`price` int(6),
PRIMARY KEY (`id`)
) DEFAULT CHARSET=utf8;
INSERT INTO `sales` (`id`, `date`, `price`) VALUES
('1', '2019-01-06','25000');
CREATE TABLE IF NOT EXISTS `purchase` (
`id` int(2) NOT NULL,
`date` varchar(50),
`price` int(6),
PRIMARY KEY (`id`)
) DEFAULT CHARSET=utf8;
SELECT GROUP_CONCAT(CONCAT_WS(',', sales.date, purchase.date)) AS date,
GROUP_CONCAT(COALESCE(sales.date, ''), ',', coalesce(purchase.date, '')),
GROUP_CONCAT(COALESCE(purchase.date, ''), ',', coalesce(sales.date, ''))
FROM sales LEFT JOIN purchase ON 1=1;
| date | GROUP_CONCAT(COALESCE(sales.date, ''), ',', coalesce(purchase.date, '')) | GROUP_CONCAT(COALESCE(purchase.date, ''), ',', coalesce(sales.date, '')) |
|---|---|---|
| 2019-01-06 | 2019-01-06, | ,2019-01-06 |