试试这个
select 商品ID,定价,sum(数量) from
(select * from biao1 union all select * from biao2) group by 商品ID,定价
用UNION ALL
select 商品ID,定价,sum(数量) from
(select * from biao1 union all select * from biao2) group by 商品ID,定价
select * from 表1
union all
select * from 表2
和内连接查询一样，称为自连接查询 。求采纳
内容全部来源于网络收集，如有侵权，请联系网站删除：QQ：24596024