我已经有这样的查询结果
+-----------+------------+---------------+--------+
| DetailsNo | SaleDate | Country | Value |
+-----------+------------+---------------+--------+
| 277 | 2012-02-10 | PHI | 42 |
| 279 | 2012-02-10 | PHI | 10 |
| 280 | 2012-02-10 | USA | 30 |
| 281 | 2012-02-10 | USA | 25 |
| 282 | 2012-02-10 | FRA | 65 |
| 283 | 2012-02-10 | FRA | 36 |
| 284 | 2012-02-10 | GER | 47 |
+-----------+------------+---------------+--------+
我需要添加另一列并显示某种订单号，如下所示：
+-----------+------------+---------------+--------+--------+
| DetailsNo | SaleDate | Country | Value | Order |
+-----------+------------+---------------+--------+--------+
| 277 | 2012-02-10 | PHI | 42 | 1 |
| 279 | 2012-02-10 | PHI | 10 | 2 |
| 280 | 2012-02-10 | USA | 30 | 1 |
| 281 | 2012-02-10 | USA | 25 | 2 |
| 282 | 2012-02-10 | FRA | 65 | 1 |
| 283 | 2012-02-10 | FRA | 36 | 2 |
| 284 | 2012-02-10 | GER | 47 | 1 |
+-----------+------------+---------------+--------+--------+
这可能吗？
最佳答案
您可以为此使用变量：
SELECT DetailsNo, SaleDate, Country, Value,
@rn := IF(@c = Country, @rn + 1,
IF(@c := Country, 1, 1)) AS 'Order'
FROM mytable
CROSS JOIN (SELECT @rn := 0, @c := '') AS vars
ORDER BY Country, DetailsNo
Demo here
关于mysql - 订单行和显示订单号，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/36496507/