Question

我有两个查询加入了union All。

SELECT  select 'Finished' AS Status,amount AS amount,units As Date
from table1 WHERE Pdate > cdate AND name =@name
UNION ALL
SELECT  select 'Live' AS Live,amount,units 
from table1  Where Pdate = cdate And name =@name

结果

Status     amount   units
Finished     100    20
Live         200    10

当任一查询提取空集时，我只得到一行，如果两者都取空集，那么我没有行

那么我怎样才能得到这样的结果

Status     amount   Units
Finished     100    20
Live         0      0

OR

Status     amount   Units
Finished     0      0
Live         200    10

OR

Status     amount   Units
Finished      0          0
Live          0          0

感谢。

Answer 1

我认为你可以使用总和来做到这一点？如果sum在没有行时不返回0，则替换为Coalesce(sum(amount), 0) as amount

SELECT  select 'Finished' AS Status,sum(amount) AS amount, sum(units) As Unit
from table1 WHERE Pdate > cdate AND name =@name
UNION ALL
SELECT  select 'Live' AS Status, sum(amount) as amount, sum(units) as Unit
from table1  Where Pdate = cdate And name =@name

如果你不想对结果求和那么只需要合并就可以了吗？ coalesce(amount, 0) As amount等......

Answer 2

我只是想指出你的查询是不必要的复杂，嵌套选择和联合all。编写查询的更好方法是：

select (case when pdate > cdate then 'Finished' else 'Live' end) AS Status,
        amount AS amount, units As Date
from table1
WHERE Pdate >= cdate AND name = @name

此查询不会产生您想要的内容，因为它只生成有数据的行。

获取额外行的一种方法是扩充原始数据，然后检查是否需要。

select status, amount, units as Date
from (select Status, amount, units,
             row_number() over (partition by status order by amount desc, units desc) as seqnum
      from (select (case when pdate > cdate then 'Finished' else 'Live' end) AS Status,
                    amount, units, name
            from table1
            WHERE Pdate >= cdate AND name = @name
           ) union all
           (select 'Finished', 0, 0, @name
           ) union all
           (select 'Live', 0, 0, @name
           )
          ) t
where (amount > 0 or units > 0) or
      (seqnum = 1)

这会添加您想要的额外行。然后它会枚举它们，所以它们会以任何顺序排在最后。它们被忽略，除非它们是序列中的第一个。

Answer 3

尝试这样的事情

with stscte as
(
select 'Finished' as status
union all 
select 'Live'
),
datacte
as(
select 'Finished' AS Status,amount AS amount,units As Date 
from table1 WHERE Pdate > cdate AND name =@name 
UNION ALL 
select 'Live' ,amount,units  
from table1  Where Pdate = cdate And name =@name 
)
select sc.status,isnull(dc.amount,0) as amount,isnull(dc.unit,0) as unit 
from stscte sc left join   datacte dc
on sc.status = dc.status

Union ALL获取空行

3 个答案: