How to get the values for the next and next next date in a table

问题

We have a table with columns Effective_Date, CVal,CPrice

How do we query the table to return values from these 2 rows in 1 row:

CVal (NextVal) and CPrice (NextPrice) values from row with Effective_Date the next date after somedate
CVal (SecondVal) and CPrice (SecondPrice) values from row with Effective_Date the next date after the Effective_Date from #1

For ex:

Effective_Date  CVal   CPrice
01-JAN-19       1       100
01-JAN-20       2       101
01-JAN-21       3       102
01-JAN-22       4       103

Say somedate = '31-DEC-19'

Expected result

(the next date after '31-DEC-19' in the Effective_Date column is 01-JAN-20,

and the next date after that is 01-JAN-21):

NextVal NextPrice SecondVal SecondPrice
2       101       3         102

Thank you.

Edited with answer from zip (replaced "top" with where rownum = 1, since top doesn't work on my Oracle) :

  select t.* from
 (
  lead(CVal, 1) over(order by Effective_Date) as NextVal 
  ,lead(CPrice, 1) over(order by Effective_Date) as NextPrice  
  ,lead(CVal, 2) over(order by Effective_Date) as SecondVal 
  ,lead(CPrice, 2) over(order by Effective_Date) as SecondPrice
  from tbl where Effective_Date >=  '31-DEC-19'
  order by Effective_Date ) t
  where rownum = 1

回答1:

You can use the window functions for it

    select  
    lead(CVal, 1) over(order by Effective_Date) as NextVal 
    ,lead(CPrice, 1) over(order by Effective_Date) as NextPrice  
    ,lead(CVal, 2) over(order by Effective_Date) as SecondVal 
    ,lead(CPrice, 2) over(order by Effective_Date) as SecondPrice

    from tbl where Effective_Date >=  '31-DEC-19'
    where rownum = 1
    order by Effective_Date

Output is

NextVal NextPrice SecondVal SecondPrice
2       101       3         102

回答2:

If you want just one row, you can filter and order the table and limit the values:

select t.*
from (select t.*
      from t
      where t.effective_date > date '2019-12-31'
      order by t.effective_date
     ) t
where rownum = 1;

Then you can add lead() to pull in additional columns from the "next" row:

select t.*
from (select t.*, lead(cval) over (order by effective_date) as next_cval,
             lead(price) over (order by effective_date) as next_price
      from t
      where t.effective_date > date '2019-12-31'
      order by t.effective_date
     ) t
where rownum = 1;

来源：https://stackoverflow.com/questions/59901871/how-to-get-the-values-for-the-next-and-next-next-date-in-a-table

标签

sql

Oracle

date

oracle11g