关于横向合并两个无关联sql union 注意重点是无关联

Question

SELECT COUNT(*) AS '入库量' FROM cti_record_files AS aa

SELECT COUNT(*) AS '初检量' FROM cti_record_files WHERE IS_EVALUATE = '2'

预想合并后

Answer 1

这样试试

select sum('入库量' ) as '入库量'  , sum('初检量' ) as '初检量'  from (
SELECT COUNT(*) AS '入库量'  , 0 as  '初检量' FROM cti_record_files AS aa
union all
SELECT 0 as  '入库量'  , COUNT(*) AS '初检量' FROM cti_record_files WHERE IS_EVALUATE = '2'
) C

如果是同一张表， 按表面需求

这种方式也可以达到效果

select sum(t1) as 入库量  , sum(t2) as 初检量 from (
select 1 as t1 , case IS_EVALUAT  when   '2'  then 1 else 0 end as t2
from  cti_record_files  ) ;