也不知道我标题说得是不是确切,下面来举例说明我的需求吧
例如有如下三个表:
tb_a: aid title type level
-------------------------------
1 标题1 1 1
2 标题2 1 2
3 标题3 2 1
4 标题4 2 2
=============================
tb_t: tid name
-------------------------
1 类别1
2 类别2
==============================
tb_l: lid name
--------------------------
1 等级1
2 等级2
=========================== 现在想要查询出来的结果集如下显示:
aid title type level
1 标题1 类别1 等级1
2 标题2 类别1 等级2
3 标题3 类别2 等级1
4 标题4 类别2 等级2================================不知道这样可不可以直接在存储过程中直接完成所有查询,并返回想要的结果集呢?
可以的话那么该怎么做?
例如有如下三个表:
tb_a: aid title type level
-------------------------------
1 标题1 1 1
2 标题2 1 2
3 标题3 2 1
4 标题4 2 2
=============================
tb_t: tid name
-------------------------
1 类别1
2 类别2
==============================
tb_l: lid name
--------------------------
1 等级1
2 等级2
=========================== 现在想要查询出来的结果集如下显示:
aid title type level
1 标题1 类别1 等级1
2 标题2 类别1 等级2
3 标题3 类别2 等级1
4 标题4 类别2 等级2================================不知道这样可不可以直接在存储过程中直接完成所有查询,并返回想要的结果集呢?
可以的话那么该怎么做?
select a.aid,a.title,b.name as type,c.name as level
from tb_a a,tb_t b,tb_l c
where a.type = b.tid and a.level = c.lid
--orselect a.aid,a.title,b.name as type,c.name as level
from tb_a a join tb_t b on a.type = b.tid
join tb_l c on a.level = c.lid
select a.aid,a.title,a.name as type,l.name as level
(select a.aid,a.title,a.level ,t.name from tb_a a left join tb_t t on a.type=t.tid) a
left join tb_l l
on a.level=l.lid
from tb_a a
left join tb_t b on a.type = b.tid
left join tb_l c on a.level = c.lid
a.aid,a.title,b.name as type,c.name as level
from
tb_a a
left join tb_t b on a.type = b.tid
left join tb_l c on a.level = c.lid