SQL，如何将两个不同查询的两个总和相加

Question

我试图在两种不同的条件下获取同一变量的总和。只是想知道是否有办法将这些添加在一起。查询的细节并不太相关。基本上只是尝试将第一个总和与第二个总和相加。

例如--

第一个查询：

  select sum(amt_tot)
  from agbgift, aprdclb
  where agbgift_id = '1' and agbgift_id = aprdclb_id  

第二次查询：

  select sum(amt_tot)
  from agbgift, aprxref, aprdclb where 
  aprxref_id = '1' and
  agbgift_id = aprxref_xref_id and
  aprxref_id = aprdclb_id and 
  xref_code in ('SPS','BUS','ORG','OWN','FDN' );

我正在寻找的最终结果是'First Query Sum' + 'Second Query Sum'

Answer 1

在这种情况下，就这么简单：

SELECT
 /* Query 1 (in parentheses) */
 (select sum(amt_tot)
  from agbgift, aprdclb
  where agbgift_id = '1' and agbgift_id = aprdclb_id)

  + /* plus */

 /* Query 2 (also in parentheses) */
  (select sum(amt_tot)
  from agbgift, aprxref, aprdclb where 
  aprxref_id = '1' and
  agbgift_id = aprxref_xref_id and
  aprxref_id = aprdclb_id and 
  xref_code in ('SPS','BUS','ORG','OWN','FDN' ))

Answer 2

with 子句很方便，如果 with 不起作用，可以在 from 子句中使用别名

with b (  select sum(amt_tot) as bsum
  from agbgift, aprxref, aprdclb where 
  aprxref_id = '1' and
  agbgift_id = aprxref_xref_id and
  aprxref_id = aprdclb_id and 
  xref_code in ('SPS','BUS','ORG','OWN','FDN' ))
, a (select sum(amt_tot) asum
  from agbgift, aprdclb
  where agbgift_id = '1' and agbgift_id = aprdclb_id   )   
select a.asum + b.bsum
from a, b  

在这种情况下确实如此：

select a.asum + b.bsum
from (select sum(amt_tot) asum
  from agbgift, aprdclb
  where agbgift_id = '1' and agbgift_id = aprdclb_id) as a, 
  (  select sum(amt_tot) as bsum
  from agbgift, aprxref, aprdclb where 
  aprxref_id = '1' and
  agbgift_id = aprxref_xref_id and
  aprxref_id = aprdclb_id and 
  xref_code in ('SPS','BUS','ORG','OWN','FDN' )) as b