create table t1 -- 商品表
(
id int identity,
name varchar (20)
)
insert into t1 (name ) values ('a');
insert into t1 (name ) values ('b');
create table t2 --销售表
(
name varchar(20),
sale int
)
insert into t2 (name ,sale )values ('a',10)
create table t3 --库存表
(
name varchar(20),
inventory int
)
insert into t3 (name,inventory ) values ('a',100);
insert into t3 (name ,inventory ) values ('b',100);
select a.*,
c.inventory -ISNULL(b.sale,0) as 库存,
ISNULL(b.sale,0) as 销量 from
(select * from t1) a
left join
(select * from t2 ) b
on a.name =b.name
left join
(select * from t3) c
on a.name =c.name
温馨提示:答案为网友推荐,仅供参考