二表合并

二表数据合并到同一个表：

select * from T1
select * from T2

select a.*,b.OutQty,c.InQty 
from (
    select [DATE] from t1
    union 
    select [DATE]  from t2
) a
left join t1 b on a.[DATE] =b.[DATE] 
left join t2 c on a.[DATE] =c.[DATE]