GUID             projectid        Time        
aaaa...           项目A组         2012-2-1
zzzz...           项目A组         2012-2-1
bbbb...           项目A组         2012-2-2
cccc..            项目B组         2012-2-2
dddd..            项目C组         2012-2-3
eeee...           项目B组         2012-2-1

GUID         projectid      Time         
aaaa...       项目A组     2012-2-1
bbbb...       项目A组     2012-2-2
eeee...       项目B组     2012-2-1
ffff...       项目W组     2012-2-5
xxxx...       项目A组     2012-2-1
yyyy...       项目A组     2012-2-1

Time        projectid    Order表总数     Come表总数     两表之和总数（去重）
2012-2-1     项目A组         2               3                 4
2012-2-1     项目B组         1               1                 1
2012-2-2     项目A组         1               1                 1
2012-2-2     项目B组         1               0                 1
2012-2-3     项目C组         1               0                 1
2012-2-5     项目W组         0               1                 1

select Time,projectid,
       Order表总数=sum(case when type='Order' then 1 else 0 end),
       Come表总数=sum(case when type='Come' then 1 else 0 end), 
       两表之和总数=count(distinct GUID)
from (select *,type='Order' from [Order]
       union all
      select *,type='Come' from Come) t
group by Time,projectid

------解决方案--------------------

SQL code
select Time,projectid,count(o.*) as Order表总数,count(c.*) as Come表总数 
,count(v.*) as 两表之和总数（去重）

from order as o, Come as c,(select * from order as o unionselect * from Come as c) as v

group by Time,projectid

------解决方案--------------------

SQL code

--> 测试数据: @order表
declare @order表 table (GUID varchar(4),projectid varchar(7),Time datetime)
insert into @order表
select 'aaaa','项目A组','2012-2-1' union all
select 'zzzz','项目A组','2012-2-1' union all
select 'bbbb','项目A组','2012-2-2' union all
select 'cccc','项目B组','2012-2-2' union all
select 'dddd','项目C组','2012-2-3' union all
select 'eeee','项目B组','2012-2-1'

--> 测试数据: @come表
declare @come表 table (GUID varchar(4),projectid varchar(7),Time datetime)
insert into @come表
select 'aaaa','项目A组','2012-2-1' union all
select 'bbbb','项目A组','2012-2-2' union all
select 'eeee','项目B组','2012-2-1' union all
select 'ffff','项目W组','2012-2-5' union all
select 'xxxx','项目A组','2012-2-1' union all
select 'yyyy','项目A组','2012-2-1'

select 
    Time=convert(varchar(10),Time,120),projectid,
    [Order表总数]=sum(case when c=1 then 1 else 0 end),
    [Come表总数]=sum(case when c=2 then 1 else 0 end),
    [总数]=count(distinct GUID)
from(select *,1 as c from @order表 union all select *,2 from @come表) a 
group by Time,projectid

/*
Time       projectid Order表总数    Come表总数     总数
---------- --------- ----------- ----------- -----------
2012-02-01 项目A组      2           3           4
2012-02-01 项目B组      1           1           1
2012-02-02 项目A组      1           1           1
2012-02-02 项目B组      1           0           1
2012-02-03 项目C组      1           0           1
2012-02-05 项目W组      0           1           1
*/