使用相同的DATE条目计算所有值 - SQL

时间:2017-03-07 17:01:41

标签: sql postgresql

我在以下架构中有事件表:

ID

name(String)

created_at(DateTime)

description(String)

事件应按发生的日期进行分组并计算

我有这个:

SELECT DISTINCT
  DATE(events.created_at)             AS day,
  description                         AS description,
  COUNT(*)                            AS count
FROM EVENTS 
WHERE name = 'trained'
GROUP BY day, events.id
ORDER BY day ASC``

但是这总是以 count

返回1

我尝试了一些关于 COUNT() GROUP BY 的变体,但没有一个有效

2 个答案:

答案 0 :(得分:1)

希望能帮助你

SELECT DATE(events.created_at) AS day,
COUNT(description) AS count
FROM EVENTS 
WHERE name = 'trained'
GROUP BY day
ORDER BY day ASC``

答案 1 :(得分:0)

这很好用,我误读了(并且认为我必须使用events.id,实际上我必须使用events.description作为必须

SELECT DISTINCT
      DATE(events.created_at)             AS day,
      description                         AS description,
      COUNT(*)                            AS count
    FROM EVENTS 
    WHERE name = 'trained'
    GROUP BY day, events.description
    ORDER BY day ASC

但是,谢谢大家的帮助,我非常感谢你的时间