Question

例如，服务器时间为15:00:00。我运行以下查询，但它给我错误的结果。这是我的查询

SELECT 
    CASE 
      WHEN TIME(NOW()) BETWEEN '08:00:01' AND '10:00:00' 
         THEN 1 
      WHEN TIME(NOW()) BETWEEN '14:00:01' AND '08:00:00' 
         THEN 2 
      ELSE 0 
    END AS IdShift

我的查询出了什么问题？从这种情况下，我的预期结果是2。但是它给了我0

Answer 1

在BETWEEN子句中，您必须先指定较低的值，然后再指定较高的值。
因此，您必须将BETWEEN '14:00:01' AND '08:00:00'更改为BETWEEN '08:00:00' AND '14:00:01'。

当您想从14:00到第二天 08:00时，您必须包括日期。

您可以这样做：

SELECT 
    CASE 
      WHEN NOW() BETWEEN CONCAT(CURDATE(), ' 08:00:01') AND CONCAT(CURDATE(), ' 10:00:00')
         THEN 1 
      WHEN NOW() BETWEEN CONCAT(CURDATE(), ' 14:00:01') AND CONCAT(CURDATE() + INTERVAL 1 DAY, ' 08:00:00')
         THEN 2 
      ELSE 0 
    END AS IdShift

Answer 2

如另一个答案中所述，对于between，下界始终是第一个。我不是between的粉丝，但是您需要分开条件：

SELECT (CASE WHEN TIME(NOW()) BETWEEN '08:00:01' AND '10:00:00' 
             THEN 1 
             WHEN TIME(NOW()) BETWEEN '14:00:01' AND '23:59:59' 
             THEN 2
             WHEN TIME(NOW()) BETWEEN '00:00:00' AND '08:00:00' 
             THEN 2 
             ELSE 0 
        END) AS IdShift

或者，用or来表达这一点：

SELECT (CASE WHEN TIME(NOW()) > '08:00:00' AND TIME(NOW()) <= '10:00:00' 
             THEN 1 
             WHEN TIME(NOW()) > '14:00:00' OR TIME(NOW()) < '08:00:00' 
             THEN 2
             ELSE 0 
        END) AS IdShift

我倾向于将逻辑改变一两分钟并使用几个小时：

(case when hour(now()) >= 8 and hour(now()) < 10
      then 1
      when hour(now()) >= 14 or hour(now()) < 8
      then 2
 end)

如何以24小时计算显示时间结果

2 个答案: