Redshift 按周分组

Question

我正在尝试按周计算我的表，但该DATE_TRUNCT('week',date)函数将星期一视为一周的开始，但我需要从星期日开始一周。

这是查询，它运行正常，但从星期一开始......

SELECT DATE_TRUNC('week',myDate) AS Reference,
       column1 AS Item1,
       column2 AS Item2,
       COUNT(*) AS Volume,
       COUNT(CASE WHEN status = 'status1' THEN 1 END) AS Status1,
       COUNT(CASE WHEN status = 'status2' THEN 1 END) AS Status2,
       COUNT(CASE WHEN status = 'status2' AND fase = '1' THEN 1 END) AS Fase1,
       COUNT(CASE WHEN status = 'status2' AND fase = '2' THEN 1 END) AS Fase2,
       COUNT(CASE WHEN status = 'status2' AND fase = '3' THEN 1 END) AS Fase3
FROM myTable
WHERE DATE_TRUNC('week',myDate) = DATE_TRUNC('week',TO_DATE('12/25/2016 00:00:00','MM/dd/yyyy'))
GROUP BY 1,
         2,
         3;

到目前为止，我只尝试了另一个甚至没有运行的查询，我不知道为什么，它只是说“在“整数”处或附近出现“语法错误”：

SELECT DATE_TRUNC('week',myDate) - integer '1' AS Reference,
       column1 AS Item1,
       column2 AS Item2,
       COUNT(*) AS Item3,
       COUNT(CASE WHEN status = 'status1' THEN 1 END) AS Status1,
       COUNT(CASE WHEN status = 'status2' THEN 1 END) AS Status2,
       COUNT(CASE WHEN status = 'status2' AND fase = '1' THEN 1 END) AS Fase1,
       COUNT(CASE WHEN status = 'status2' AND fase = '2' THEN 1 END) AS Fase2,
       COUNT(CASE WHEN status = 'status2' AND fase = '3' THEN 1 END) AS Fase3
FROM myTable
WHERE myDate between ( DATE_TRUNC('week', TO_DATE('12/25/2016 00:00:00','MM/dd/yyyy' ) - integer '1' ) and ( DATE_TRUNC('week', TO_DATE('12/25/2016 00:00:00','MM/dd/yyyy' ) ) + integer '5' )
GROUP BY 1,
         2,
         3;

此外，即使此查询正确运行，它也会显示第 18/Dec - 24/Dec 周的计数，而不是第 25/Dec - 31/Dec 周的计数，在 25/Dec 的情况下。如果是星期天，其他日子也会发生同样的情况。

编辑：我刚刚在这个博客中找到了解决方案：https : //blog.modeanalytics.com/date-trunc-sql-timestamp-function-count-on/ 它介绍了 date_trunct 函数，有人在评论中提出了同样的问题. 这是我解决的查询以供将来参考其他人：

SELECT date_trunc('WEEK',(myDate + interval '1 day'))- interval '1 day' AS Reference
       column1 AS Item1,
       column2 AS Item2,
       COUNT(*) AS Volume,
       COUNT(CASE WHEN status = 'status1' THEN 1 END) AS Status1,
       COUNT(CASE WHEN status = 'status2' THEN 1 END) AS Status2,
       COUNT(CASE WHEN status = 'status2' AND fase = '1' THEN 1 END) AS Fase1,
       COUNT(CASE WHEN status = 'status2' AND fase = '2' THEN 1 END) AS Fase2,
       COUNT(CASE WHEN status = 'status2' AND fase = '3' THEN 1 END) AS Fase3
FROM myTable
WHERE  ( date_trunc('WEEK',(myDate + interval '1 day'))- interval '1 day') = ( DATE_TRUNC('week',TO_DATE('12/24/2016 00:00:00','MM/dd/yyyy') + interval '1 day'  ) - interval '1 day' )
GROUP BY 1,
         2,
         3;

Answer 1

我找不到任何简单的方法将周设置为周日到周六。但是你可以试试这个：

select date_trunc('week', myDate + 1) - 1 as Reference,
       ...
from myTable
where ...
group by date_trunc('week', myDate + 1), ...

这里的诀窍是在做的时候移动一天group by。