Question

我有一张桌子

Recordid Price  Start date    end date 
-----------------------------------------
1        20     2017-10-01    2017-10-02
2        20     2017-10-03    2017-10-04
3        30     2017-10-05    2017-10-05
4        20     2017-10-06    2017-10-07

我希望在它开始时和结束时获得所有价格，因此我的结果集将是

20.  2017-10-01.  2017-10-04
30.  2017-10-05.  2017-10-05
20.  2017-10-06.  2017-10-07

我有问题要弄清楚

它是一个Oracle数据库

Answer 1

我用下面的代码弄明白了

SELECT distinct price
      , case when start_dt is null then lag(start_dt) over (order by start_date) 
             else start_dt end realstart
      , case when end_dt is null then lead(end_dt) over (order by end_date) 
             else  end_dt end realend   
FROM (SELECT case when nvl(lag(price) over (order by start_date),-1) <> price then start_date end start_dt
           , case when nvl(lead(price) over (order by end_date),-1) <>price then end_date end end_dt
           , price 
           , start_date
           , end_date 
       FROM t) main 
WHERE start_dt is not null 
   or end_dt is not null

Answer 2

以下是一种可能适用于您的方法：

select price, min(start_date), max(end_date)
from (select t.*,
             sum(case when prev_price = price and prev_end_date = start_date - 1
                      then 0 else 1
                 end) over (order by t.start_date) as grp
      from (select t.*,
                   lag(t.end_date) over (order by t.start_date) as prev_end_date,
                   lag(t.price) over (order by t.start_date) as prev_price
            from t
           ) t
     ) t
group by price, grp

Answer 3

根据您的示例数据，我认为您希望每当价格按记录ID的顺序更改时都有开始日期和结束日期。以下查询可能包含比必要更多的子查询，因为可读性。内部选择确定何时更改价格，称为组更改。来自该组的下一级别的滚动总和。这是可能的，因为只有组更改包含值＆gt;其余的很明显。

 // for example i =10

  1) String.valueOf(i);//Now it will return "10"  

  2 String s=Integer.toString(i);//Now it will return "10" 

  3) StringBuilder string = string.append(i).toString();

   //i = any integer nuber

  4) String string = "" + i; 

  5)  StringBuilder string = string.append(i).toString();

  6) String million = String.format("%d", 1000000)

使用以下数据进行测试（请注意，我已经为您提供的示例数据添加了一些记录，因为我希望拥有一个包含三个记录的组）

SELECT GRP, 
       PRICE, 
       MIN("Start date") AS "Start date", 
       MAX("end date") AS "end date"
  FROM ( SELECT sub.*,
                SUM(GROUP_CHANGE) OVER (ORDER BY RECORDID) AS GRP
           FROM ( SELECT t.*,
                         CASE 
                            WHEN RECORDID = LAG(t.RECORDID) OVER (ORDER BY t.PRICE, t.RECORDID) + 1 
                               THEN 0 
                            ELSE RECORDID 
                         END AS GROUP_CHANGE
                    FROM t ) sub ) fin
 GROUP BY GRP, PRICE 
 ORDER BY GRP


       GRP      PRICE Start date end date
---------- ---------- ---------- --------
         1         20 01.10.17   04.10.17 
         4         30 05.10.17   05.10.17 
         8         20 06.10.17   11.10.17

具有开始和结束日期的组价

3 个答案: