BigQuery SQL-如果两列在连续几天内，则将它们连接起来

我正在寻找一种方法来调整在BigQuery中运行的sql查询，以返回连续发生两天甚至三天的已发送事件类型的单计数总数

SELECT date(EventDate) as EventDate, EventType, count(*) as count FROM `Database.Table`
    where date(EventDate) > DATE_SUB (CURRENT_DATE, INTERVAL 100 DAY)
    Group by 1,2 
    ORDER by 1,2

以上查询的答复：

| Row    | EventDate | EventType | count |
| ------ | --------- |-----------|-------|
| 1      | 2019-02-06|  Sent     |    4  |
| 2      | 2019-02-07|  Sent     |    5  |
| 3      | 2019-02-12|  NotSent  |    7  |
| 4      | 2019-02-13|  Bounces  |    22 |
| 5      | 2019-02-14|  Bounces  |    22 |
| 6      | 2019-03-06|  Sent     |    2  |
| 7      | 2019-03-07|  Sent     |    4  |
| 8      | 2019-03-07|  NotSent  |    5  |
| 9      | 2019-03-12|  Bounces  |    7  |
| 10     | 2019-03-13|  Sent     |    22 |
| 11     | 2019-04-05|  Sent     |    2  |

我想得到的答复是：

| Row    | EventDate | EventType | count |
| ------ | --------- |-----------|-------|
| 1      | 2019-02-06|  Sent     |    9  |
| 2      | 2019-02-12|  NotSent  |    7  |
| 3      | 2019-02-13|  Bounces  |    22 |
| 4      | 2019-02-14|  Bounces  |    22 |
| 5      | 2019-03-06|  Sent     |    6  |
| 6      | 2019-03-07|  NotSent  |    5  |
| 7      | 2019-03-12|  Bounces  |    7  |
| 8      | 2019-03-13|  Sent     |    22 |
| 9      | 2019-04-05|  Sent     |    2  |

---

这样我就可以连续几天将两个计数与EventType“Sent”连接起来，并显示其他EventType而不将它们连接起来，例如Bounces和NotSent。

这是一个间隙和孤岛问题。最简单的方法是使用行数和减法来识别岛屿。然后汇总：

select min(row), eventType, min(eventDate), sum(count)
from (select t.*,
             row_number() over (partition by eventType order by eventDate) as seqnum
      from t
     ) t
group by eventType, dateadd(eventDate, interval -seqnum day)

---

我编写了一个查询，合并了表中所有连续的2天。 它提供与您想要的完全相同的输出

我想你在第五行的意思是“2019-03-06”，所以我在我的虚拟数据部分修复了它

WITH
data AS (
  SELECT CAST('2019-02-06' as date) as EventDate, 4 as count union all
  SELECT CAST('2019-02-07' as date) as EventDate, 5 as count union all
  SELECT CAST('2019-02-12' as date) as EventDate, 7 as count union all
  SELECT CAST('2019-02-13' as date) as EventDate, 22 as count union all
  SELECT CAST('2019-03-06' as date) as EventDate, 2 as count
),
data_with_steps AS (
  SELECT *, 
    IF(DATE_DIFF(EventDate, LAG(EventDate) OVER (ORDER BY EventDate), day) > 2, 1, 0) as new_step
  FROM data
),
data_grouped AS (
  SELECT *, 
    SUM(new_step) OVER (ORDER BY EventDate) as step_group
  FROM data_with_steps
)
SELECT MIN(EventDate) as EventDate, sum(count) as count
FROM data_grouped
GROUP BY step_group

那么，它是如何工作的呢？ 首先，我计算与前一天的日期差。如果超过2天，我将新列new_步骤的值设置为1，否则设置为0。 然后，我计算new_step列的累积和，并将其命名为step_group。 前两个步骤的输出为：

在最后一步，我将表按步骤分组，并将最小日期作为事件日期，将计数相加以获得组计数。

编辑： 为了添加其他事件而不按分组，我添加了一个新版本。 我认为最直观、最简单的方法就是使用Union All解决这个问题。 因此，您可以使用更新后的查询来包含其他事件，而无需分组

WITH
data AS (
  SELECT CAST('2019-02-06' as date) as EventDate, 'Sent' as EventType, 4 as count union all
  SELECT CAST('2019-02-07' as date) as EventDate, 'Sent' as EventType, 5 as count union all
  SELECT CAST('2019-02-12' as date) as EventDate, 'Sent' as EventType, 7 as count union all
  SELECT CAST('2019-02-13' as date) as EventDate, 'Sent' as EventType, 22 as count union all
  SELECT CAST('2019-03-06' as date) as EventDate, 'Sent' as EventType, 2 as count union all
  SELECT CAST('2019-02-12' as date) as EventDate, 'NotSent' as EventType, 7 as count union all
  SELECT CAST('2019-03-07' as date) as EventDate, 'NotSent' as EventType, 5 as count union all
  SELECT CAST('2019-02-13' as date) as EventDate, 'Bounces' as EventType, 22 as count union all
  SELECT CAST('2019-02-14' as date) as EventDate, 'Bounces' as EventType, 22 as count union all
  SELECT CAST('2019-03-12' as date) as EventDate, 'Bounces' as EventType, 7 as count
),
data_with_steps AS (
  SELECT *, 
    IF(DATE_DIFF(EventDate, LAG(EventDate) OVER (ORDER BY EventDate), day) > 2, 1, 0) as new_step
  FROM data
  WHERE EventType = 'Sent'
),
data_grouped AS (
  SELECT *, 
    SUM(new_step) OVER (ORDER BY EventDate) as step_group
  FROM data_with_steps
)
SELECT EventType, MIN(EventDate) as EventDate, sum(count) as count
FROM data_grouped
GROUP BY EventType, step_group

UNION ALL

SELECT EventType, EventDate, count
FROM data
WHERE EventType != 'Sent'

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如何在第一个响应表中有2019-02-06的两行？我是遗漏了什么，还是它们只是同一天？@Sab感谢good spot，今天稍后我将尝试您的示例。是否有方法将EventType添加到结果中？如果是这样的话，我的最后一步是在结果中有其他事件类型，但只在“发送”上进行延迟。您能提供带有其他事件类型和预期输出的示例输入数据吗？我已经更新了问题，我还测试了将EventType“Sent”的WHERE移动到子查询，尽管这样做仍然只显示Sent类型，忽略了Bounces和NotSent。数据步骤为SELECT*，IFDATE\u DifferentiventDate，LAGEventDate超过ORDER BY EventDate，day>1,1,0作为新步骤，从数据中的EventType（如“发送”）添加了问题的新版本，因此您可以检查。看起来不错，我唯一添加的是在最终选择中添加了ORDER BY EventDate，我会再次检查数据，但最初看起来不错，非常感谢。