Question

我正在处理按flag_color排序的查询，但我希望它按颜色优先：

此查询现在返回：

SELECT   flag_color as color 
FROM     clinic_performance_flags 
GROUP BY clinic_user_id 
ORDER BY flag_color ASC

green
green
green
green
red
red
red
red
yellow
yellow
yellow

但我想更改顺序，因此订单变为（red应始终为第一，yellow秒和green第三）示例：

red
red
red
red
yellow
yellow
yellow
yellow
green
green
green
green

Answer 1

使用FIELD功能。

SELECT flag_color AS color 
FROM clinic_performance_flags 
GROUP BY clinic_user_id 
ORDER BY FIELD(flag_color ,'red','yellow','green'), flag_color ASC

Answer 2

在CASE：

中使用ORDER BY

SELECT   flag_color as color 
FROM     clinic_performance_flags 
GROUP BY clinic_user_id 
ORDER BY CASE WHEN flag_color = 'red'    THEN 1
              WHEN flag_color = 'yellow' THEN 2
              WHEN flag_color = 'green'  THEN 3
                                         ELSE 4
         END, flag_color ASC

Answer 3

您可以使用CASE声明

SELECT   flag_color as color 
FROM     clinic_performance_flags 
GROUP BY clinic_user_id 
ORDER BY CASE WHEN flag_color = 'red' THEN 1
              WHEN flag_color = 'yellow' THEN 2
              WHEN flag_color = 'green' THEN 3
              ELSE 4 END

如何按类型排序 - sql

3 个答案: