Oracle - 按类别分组，日期范围[重复]

Question

我有问题。我想根据图像中的数据编写oracle查询数据库

将创建结果：

START_DATE         |END_DATE           |COLOR
-------------------|-------------------|------
2017-05-25 15:39:39|2017-05-25 15:41:06|GREEN
2017-05-25 15:41:06|2017-05-25 15:53:27|ORANGE
2017-05-25 15:53:27|2017-05-25 15:57:16|GREEN
2017-05-25 15:57:16|2017-05-25 15:59:24|YELLOW

等等……

Answer 1

您正在尝试查找相邻的值。一种方法使用不同的行号：

select min(start_date) as start_date, max(start_date) as end_date, color
from (select t.*,
             row_number() over (order by start_date) as seqnum,
             row_number() over (partition by color order by start_date) as seqnum_c
      from t
group by (seqnum - seqnum_c), color;

解释为什么行号的差异会起作用有点挑战性。我鼓励您运行子查询并盯着数字。您应该能够看到为什么相邻颜色值的差异是恒定的。