來自日誌表的Postgres日期報告

Question

難以讓sql從postgresql數據庫中進行報告。

• cohead：cohead_id，cohead_number，cohead_orderdate
• 評論：COMMENT_ID，comment_source_id，COMMENT_DATE，COMMENT_TEXT

兩個可我有兩個表，有關列如下工作加入cohead_id = comment_source_id查找與訂單相關的所有評論。

當我們向我們的訂購準備服務提交訂單時，我們通過插入帶有相關訂單的文本「已提交」的評論進行登錄。當我們使用訂單準備服務關閉訂單時，我們爲該訂單插入「已開票」評論。

我想要做的是獲得一個時間段（比如上個月）的每一天的列表，並計算當天或之前提交但尚未開具發票的訂單數那天。

我遇到了一些概念問題，我嘗試過的連接速度很慢。

任何想法？

Answer 1

拍攝日期'20130731','20130805'作爲示例的開始和結束日期，這個查詢將每天在這兩個日期之間返回您需要的數量。您可以更改真實查詢的參數。

;with cte as (
    select d::date as d 
    from generate_series('20130731', '20130805', interval '1 day') as d 
) 
select 
    cte.d, 
    count(o.cohead_id) as cnt 
from cte 
    left outer join cohead as o on 
     o.cohead_orderdate <= cte.d and 
     not exists (
      select * 
      from comment as c 
      where 
       c.comment_date <= cte.d and 
       c.comment_text = 'Invoiced' and 
       c.comment_source_id = o.cohead_id 
     ) 
group by cte.d 
order by cte.d 

請參閱SQL FIDDLE EXAMPLE - 您可以添加/刪除行並檢查它是否正常工作。

希望有所幫助。

UPDATE： 如果你想獲得提交日期，而不是訂單日期，你不必來查詢訂單表都：

;with cte as (
    select d::date as d 
    from generate_series('20130731', '20130805', interval '1 day') as d 
), cte2 as (
    select 
     c1.comment_date as submitted_date, 
     c2.comment_date as invoiced_date, 
     count(*) as cnt 
    from comment as c1 
     left outer join comment as c2 on 
      c2.comment_source_id = c1.comment_source_id and 
      c2.comment_text = 'Invoiced' 
    where c1.comment_text = 'Submitted' 
    group by c1.comment_date, c2.comment_date 
) 
select c1.d, sum(c2.cnt) 
from cte as c1 
    left outer join cte2 as c2 on 
     c2.submitted_date <= c1.d and 
     (c2.invoiced_date is null or c2.invoiced_date > c1.d) 
group by c1.d 
order by c1.d 

看到SQL FIDDLE與更新的查詢

更新2由於OP說他有查詢性能的問題，我試着用窗口函數編寫另一個。這個想法是獲取所有類型提交的日期計數減去發票類型的評論，然後獲得滾動總額。

;with cte1 as (
    select d::date as d 
    from generate_series('20130731', '20130805', interval '1 day') as d 
), cte2 as (
    select 
     greatest('20130731', c.comment_date) as comment_date, 
     c.comment_text, count(*) as cnt 
    from comment as c 
    where 
     c.comment_text in ('Invoiced', 'Submitted') and 
     c.comment_date <= '20130805' 
    group by greatest('20130731', c.comment_date), c.comment_text 
), cte3 as (
    select 
     coalesce(cs.cnt, 0) - coalesce(ci.cnt, 0) as cnt, 
     coalesce(cs.comment_date, ci.comment_date) as comment_date 
    from (select * from cte2 where comment_text = 'Submitted') as cs 
     full outer join (select * from cte2 where comment_text = 'Invoiced') as ci on 
      cs.comment_date = ci.comment_date 
) 
select c1.d, sum(c3.cnt) over (order by c1.d) 
from cte1 as c1 
    left outer join cte3 as c3 on c3.comment_date = c1.d 
order by c1.d 

SQL FIDDLE