如何在 SQL Server 2008 中复制列数据？

Question

这是我的查询：

select 
    t.range as [score range], count(*) as [number of occurences]
from 
    (select 
         case 
            when answer_count between 0 and 5 then ' 0- 9'
            when answer_count between 5 and 10 then '10-19'
            else '20-99' end as range
     from 
         points 
     where 
         type = 'product_quiz') t 
group by 
    t.range

输出是：

/-------------------------------------\
| score range | number of occurrences |
|-------------+-----------------------|
|   10-19     |         121327        |
|    0- 9     |         129195        |
\-------------------------------------/

但我想要这样的输出：

/-----------------------------------------------------------------------------\
| score_range | number_of_occurrences | score_range1 | number_of_occurrences1 |
|-------------+-----------------------+--------------+------------------------|
|   10-19     |         121327        |    10-19     |         121327         |
|    0- 9     |         129195        |     0- 9     |         129195         |
\-----------------------------------------------------------------------------/

如何使用子查询来实现这一点？

Answer 1

如果我理解正确，您不需要子查询（除非您指的是 FROM 子句中已经存在的子查询）：

select 
    t.range as [score_range], 
    count(*) as [number_of_occurences],
    t.range as [score_range1], 
    count(*) as [number_of_occurences1]
from 
    (select 
         case 
            when answer_count between 0 and 5 then ' 0- 9'
            when answer_count between 5 and 10 then '10-19'
            else '20-99' end as range
     from 
         points 
     where 
         type = 'product_quiz') t 
group by 
    t.range

为什么你会想要这样做（以及为什么你会特别想要使用子查询）是另一个问题。