Sql 创建和删除上周的条目

通过此查询，我可以获得上周创建的所有条目：

SELECT day, COALESCE(ct, 0) AS ct
FROM  (SELECT now::date - d AS day FROM generate_series (0, 6) d) d  -- 6, not 7
  LEFT   JOIN (
     SELECT created_at::date AS day, count(*) AS ct 
     FROM   entries
     WHERE  created_at >= date_trunc('day', now()) - interval '6d'
     GROUP  BY 1
  ) e USING (day);

它返回如下结果：

 count | date
   2   |  15.01.2014
   0   |  14.01.2014
   1   |  13.01.2014
   0   |  12.01.2014
   0   |  11.01.2014
   0   |  10.01.2014
   9   |  09.01.2014

现在我还想显示上周删除的所有条目！我可以通过处的字段

deleted\u获取它们：我尝试的是：

SELECT day, COALESCE(ct, 0) AS created, COALESCE(dl,0) AS deleted
FROM  (SELECT current_date - d AS day FROM generate_series (0, 6) d) d  
LEFT   JOIN (
   SELECT created_at::date AS day, 
      count(
        CASE WHEN (created_at >= date_trunc('day', now()) - interval '6d') THEN 1 ELSE 0 END
      ) AS ct,
count(
    CASE WHEN (canceled_at >= date_trunc('day', now()) - interval '6d') THEN 1 ELSE 0 END
) AS dl  
  FROM   entries

   GROUP  BY 1
  ) e USING (day);

但那没用！现在我得到了两行相同的内容：

deleted | created | date
  2     |  2      |  15.01.2014
  0     |  0      |  14.01.2014
  1     |  1      |  13.01.2014
  0     |  0      |  12.01.2014
  0     |  0      |  11.01.2014
  0     |  0      |  10.01.2014
  9     |  9      |  09.01.2014

我错了什么？如何显示已创建和已删除的条目？
乍一看，您执行的是计数功能，而不是所需的总和，您只需对每条记录进行两次计数

sum( CASE WHEN (created_at >= date_trunc('day', now()) - interval '6d') 
       THEN 1 ELSE 0 END) AS ct,
sum(CASE WHEN (canceled_at >= date_trunc('day', now()) - interval '6d') 
       THEN 1 ELSE 0 END) AS dl  

您需要使用sum，它将在case when返回1时添加所有case，而不是count，它只计算所有值，不管它们是1还是0
 由于两个时间戳在时间范围内可以存在0-n次，并且彼此独立，因此您必须做更多的工作：

需要博士后9.3+：

WITH var(ts_min) AS (SELECT date_trunc('day', now()) - interval '6 days')
SELECT day
     , COALESCE(c.created, 0) AS created
     , COALESCE(d.deleted, 0) AS deleted
FROM   var v
CROSS  JOIN LATERAL (
   SELECT d::date AS day
   FROM   generate_series (v.ts_min
                         , v.ts_min + interval '6 days'
                         , interval '1 day') d
   ) t
LEFT   JOIN (
   SELECT created_at::date AS day, count(*) AS created
   FROM   entries
   WHERE  created_at >= (SELECT ts_min FROM var)
   GROUP  BY 1
   ) c USING (day)
LEFT   JOIN (
   SELECT canceled_at::date AS day, count(*) AS deleted
   FROM   entries
   WHERE  canceled_at >= (SELECT ts_min FROM var)
   GROUP  BY 1
   ) d USING (day)
ORDER  BY 1;

CTE
var
仅为方便提供一次启动时间戳

谢谢你的帮助！我真的不明白，所以你能添加一个正确的查询吗？谢谢请始终提供您的Postgres版本。这是对以下内容的后续操作：抱歉，我收到了
groupby 1
的语法错误，我真的不知道如何修复它！另外，我不确定这个查询是否会返回正确的结果，因为它在
created\u处创建了
left join
，而在
处也没有
cancelled\u！再次感谢你的帮助！如果你能解决这个问题，我会认为你的答案是正确的！谢谢@约翰斯米特：这些查询是错误的。我提供了一个全新的、经过测试的版本。