select 'N1' as Col,sum(a1) from table1
union all
select 'N2' as Col,sum(a2) from table1
union all
select 'N3' as Col,sum(a3) from table1

------解决方案--------------------
select 'N1',sum(a1) union all
select 'N2',sum(a2) union all
select 'N3',sum(a3)

------解决方案--------------------
SQL code
select 'N1' as N,sum(a1) AS [SUM] from table1
union all
select 'N2' as N,sum(a2) from table1
union all
select 'N3' as N,sum(a3) from table1


--or

SELECT *
FROM (SELECT SUM(a1) AS N1,SUM(a2) AS N2,SUM(a3) AS N3) AS a
PIVOT 
([Sum] FOR N IN(N1,N2,N3)) AS b

------解决方案--------------------
探讨


楼上的，哪个最好呀？


------解决方案--------------------
探讨

楼上的，哪个最好呀？


------解决方案--------------------
探讨


引用:
楼上的，哪个最好呀？

CTRL+L查看查询计划。


------解决方案--------------------
SQL code

select N='N1',[sum]=sum(a1) from table1
union all
select 'N2',sum(a2) from table1
union all
select 'N3',sum(a3) from table1