在sql中加入两条select语句

Question

我有两条select语句。第一个select返回2012年前一年的数据，而第二个select显示当前年份。我将如何加入这两个来获得我想要的输出。

select a.id, b.item, a.sum(qty) as 'yr1qty', a.yr1amt from table A 
left join table B on a.code = b.code 
where date between '04/01/2012' and '04/07/2012' 
group by a.id, b. item 

select a.id, b.item, a.sum(qty) as 'yr2qty', a.yr2amt from table A 
left join table B on a.code = b.code 
where date between '04/01/2013' and '04/07/2013' 
group by a.id, b. item 

所需的输出：

id item  yr1qty y1amt  yr2qty yr2amt 

01 item01  20  2000.00  5  500.00 
02 item02       8  400.00 
03 item03  10  1250.00 
04 item04  3  60.00  2  40.00 
05 item05       8  400.00 

Answer 1

为使用子查询全外，您应该能够加入两个连接

select 
    coalesce(a.id,b.id), 
    coalesce(a.item,b.item), 
    yr1qty, 
    yr1amt, 
    yr2qty, 
    yr2amt 
from 
    (
    select a.id, b.item, a.sum(qty) as 'yr1qty', a.yr1amt from table A 
    left join table B on a.code = b.code 
    where date between '04/01/2012' and '04/07/2012' 
    group by a.id, b. item) as a 
    full outer join 
    (
    select a.id, b.item, a.sum(qty) as 'yr2qty', a.yr2amt from table A 
    left join table B on a.code = b.code 
    where date between '04/01/2013' and '04/07/2013' 
    group by a.id, b. item 
    ) as b on a.id = b.id 

Answer 2

你需要两个？这是一个查询的结果...

select a.id, b.item, 
a.sum(
    CASE WHEN date between '04/01/2012' and '04/07/2012' 
     THEN qty 
     ELSE 0 
    END) AS 'yr1qty', a.yr1amt, 
a.sum(
    CASE WHEN date between '04/01/2013' and '04/07/2013' 
     THEN qty 
     ELSE 0 
    END) AS 'yr2qty', a.yr2amt 
from table A 
left join table B on a.code = b.code 
group by a.id, b.item 

Answer 3

您是否需要使用数据透视表？

select id,item, yr1qty,yr1amt, yr2qty, yr2amt from 
(
select a.id, b.item, a.qty, a.amt, 
    case 
     when [date] between '2012-01-04' and '2012-07-01' then 'yr1qty' 
     when [date] between '2013-01-04' and '2013-07-01' then 'yr2qty' 
     else 'oor' 
    end as yrqty, 
    case 
     when [date] between '2012-01-04' and '2012-07-01' then 'yr1amt' 
     when [date] between '2013-01-04' and '2013-07-01' then 'yr2amt' 
     else 'oor' 
    end as yramt 



from A 
left join B on a.code = b.code 
) x 
pivot (
    sum(qty) for yrqty in ([yr1qty],[yr2qty]) 
) qtyTotal 
pivot (
    sum(amt) for yramt in ([yr1amt],[yr2amt]) 
) amtTotal