select t.日期,t.数量
(select a.日期,sum(a.数量1+b.数量2) 数量 from a,b where a.日期=b.日期 gruop by a.日期
) t
order by t.数量 desc
(select a.日期,sum(a.数量1+b.数量2) 数量 from a,b where a.日期=b.日期 gruop by a.日期
) t
order by t.数量 desc
from a,b
where a.日期=b.日期
group by a.日期
order by total desc;
这样不行,A表B表中 只要一个表 出现的日期就要加入统计结果.
select 日期,sum(数量1) as cnt
from
(select 日期,数量1
union all
select 日期,数量2)
group by 日期
order by cnt desc;
from
(select 日期,数量1 form A
union all
select 日期,数量2 form B)
group by 日期
order by cnt desc;
2 from
3 (select A1,A2 from a
4 union all
5 select A1,A2 from b )
6 group by a1
7 order by cnt desc;A1 CNT
----------- ----------
2006-1-1 9
2006-1-3 7
2006-1-2 5
感谢sbaz,结帖!