select a.room_id,a.room_area,d.c_name,c.rent_money
from db_room a
left join db_rent_detail b
on a.room_id=b.room_id
inner join db_rent c
on b.rent_id=c.rent_id
inner join db_clients d
on c.c_id=d.c_id
from db_room a
left join db_rent_detail b
on a.room_id=b.room_id
inner join db_rent c
on b.rent_id=c.rent_id
inner join db_clients d
on c.c_id=d.c_id
,d.c_name
,c.rent_money
from db_room a
left join db_rent_detail b on a.room_id=b.room_id
left join db_rent c on b.rent_id=c.rent_id
left join db_clients d on c.c_id=d.c_id
from db_room , db_rent_detail , db_rent ,db_clients where db_room.room_id = db_rent_detail.room.id
and db_rent_detail.rent_id=db_rent.rent_id and db_rent.c_id=db_clients.cid
最好用關聯把,等下我試寫個你看看
a.room_id ,
a.room_area ,
d.c_name ,
c.rent_money
from
db_room a
inner join
db_rent_detail b
on
a.room_id = b.room_id
left join
db_rent c
on
b.rent_id = c.rent_id
inner join
db_clients d
on
c.c_id = c_id
xluzhong(打麻将一缺三,咋办?) 只能显示已经出租的
talantlee(團結就是力量) 的也一样多谢了,现在揭帖
when '出租' then ''
when '出租' then ''
end) as
from db_room a,db_clients b,db_rent c,db_rent_detail d
where a.room_id=b.room and b.rent_id=c.rent_id and c.c_id=d.c_id同时如果这个房间已经出租出去,
就显示承租该房间的公司名称和租金,
如果没有出租就显示为空
这个完全可以用CASE语句来实现
参考:
select a.Cname as Tcomname,b.Cname as TGoodname,D.nQuanty,c.cNote
, (case when c.iEvaluate='-1' then '差评'
when c.iEvaluate='1' then '好评'
when c.ievaluate='0' then '一般' end) as ievaluate
from Tcompany a,Tgoods b,Appraise c,orders D
where b.ID=D.nProductID and D.Id=c.order_id and a.Id=b.NsaID
and b.NsaID=@TcomID