sql - 将 row_number() 拆分为多列分区

Question

我有一个在分区上使用 row_number() 的查询。
当结果出来时，它看起来像

Product         Row_Number         Price
A               1                  25
A               2                  20
A               3                  15
B               1                  100
B               2                  10
B               3                  2

我想让结果显示在像

Product      Row1         Row2        Row3      price1       price2       price3
A            1            2           3         25           20           15
B            1            2           3         100          10           2

我应该使用 rank() 之类的东西吗？？？

我正在使用 Teradata

Answer 1

您可以再添加两个窗口函数来获得第二和第三高的价格，这应该在与您当前的 ROW_NUMBER 相同的 STAT-step 中运行，因此没有额外的开销:

select
   product,
   price as Price1,
   min(price)
   over (partition by product
         order by price desc
         rows between 1 following and 1 following) as Price2,
   min(price)
   over (partition by product
         order by price desc
         rows between 2 following and 2 following) as Price3
from tab
qualify 
   row_number() 
   over (partition by product
         order by price desc) = 1