求教关于多表关联查询的问题

Question

本帖最后由 tang_yali 于 2011-07-13 22:21:04 编辑

Answer 1

select
 isnull(a.name,''),isnull(a.guige,''),isnull(a.danjia,0)isnull(b.shuliang,0),isnull(b.kuid,0) 
from
 spk a leftr join kucun b 
on
 a.spid=b.spid

Answer 2

select
 isnull(a.name,''),isnull(a.guige,''),isnull(a.danjia,0)isnull(b.shuliang,0),isnull(b.kuid,'') 
from
 spk a leftr join kucun b 
on
 a.spid=b.spid

Answer 3

select a.name,a.guige,a.danjia,b.shuliang,b.kuid from spk a left join 
on kucun b a.spid=b.spid

Answer 4

isnull(columns,'')
isnull(cloumns,0)
isnull()函数。如果列值为空，则显示 ‘’或0，不为空则显示列值select
 isnull(a.name,''),isnull(a.guige,''),isnull(a.danjia,0)isnull(b.shuliang,0),isnull(b.kuid,'') 
from
 spk a leftr join kucun b 
on
 a.spid=b.spid