DuckDB 有没有办法按 15 分钟的间隔进行分组？

Question

我用

做了一张桌子

create table counter (
  createdat TIMESTAMP,
  tickets INT, 
  id VARCHAR
)

我想按 15 分钟的间隔对行进行分组，所以我尝试这样做：

SELECT
  SUM(tickets) AS total,
  extract(year from createdat),
  extract(month from createdat),
  extract(day from createdat),
  extract(hour from createdat)
from counter
where id = ?
group by
  extract(year from createdat),
  extract(month from createdat),
  extract(day from createdat),
  extract(hour from createdat)

通过这个查询，我只能按小时获取。但是我无法将其修改为分钟。

按 15 分钟间隔进行分组的查询如何？

Answer 1

添加一刻钟的表达式：

(extract(minute from createdat) / 15)::integer

到您的专栏：

select
  sum(tickets) AS total,
  extract(year from createdat),
  extract(month from createdat),
  extract(day from createdat),
  extract(hour from createdat),
  (extract(minute from createdat) / 15)::integer
from counter
where id = ?
group by
  extract(year from createdat),
  extract(month from createdat),
  extract(day from createdat),
  extract(hour from createdat),
  (extract(minute from createdat) / 15)::integer

转换为

integer

会截断除法结果的小数部分。

Answer 2

更简单的方法是使用

time_bucket

示例：

SELECT time_bucket(INTERVAL '15m', createdat) AS bucket, SUM(tickets)
FROM counter
GROUP BY bucket
ORDER BY bucket;