Mysql获取一个元组中的最大值

Question

我根据行数据制作一个表格，例如:

+----------------------+
| id | 1st | 2nd | 3th |
+----------------------+
|  0 |   1 |   3 |  2.5|
|  1 | 2.5 |   5 |    3|
|  2 |   4 | 3.5 |    0|
+----------------------+

我想要得到这个:

+--------------+
| id | max set | 
+--------------+
|  0 |     2nd | 
|  1 |     2nd |  
|  2 |     1st | 
+--------------+

我该怎么办？

Answer 1

您可以使用greatest()和field()来做到这一点:

select id,
       field(greatest(col1, col2, col3), col1, col2, col3) as ColWithMax
from table t;