Home Database Mysql Tutorial MySQL的双表多表联查

MySQL的双表多表联查

Jun 07, 2016 pm 04:24 PM
mysql two

最近在做EC-Mall的二次开发,遇到这么一个需求,将挂件单独显示成一个页面。由于EC-Mall的挂件是用数据模块+模块类库的方式进行的,就是使用类似smarty的形式。而单独一个页面的话,数据读取需要自己写SQL语句。 现在的问题是,需要将商品中的汽车类中的推荐

最近在做EC-Mall的二次开发,遇到这么一个需求,将挂件单独显示成一个页面。由于EC-Mall的挂件是用数据模块+模块类库的方式进行的,就是使用类似smarty的形式。而单独一个页面的话,数据读取需要自己写SQL语句。

现在的问题是,需要将商品中的汽车类中的推荐商品数据显示出来,sql如下:

select * from shop_goods as a 
	join shop_recommended_goods as b 
    where a.goods_id = b.goods_id 
    and b.recom_id = 36 
    order by b.sort_order asc 
    limit 14
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其中,表shop_goods是存储了所有商品信息的数据表,shop_recommended_goods则是将商品id与推荐id相关联的表。

MySQL多表联查例子:

下面这两个MySQL多表联查方法都可以,inner join on 更好点。表结构没贴出来,但比较好懂了。

MySQL多表联查的简单方法:

select c.nom, e.nom   
from consultant c, affaire a, besoin b, salarie sa, site s, entreprise e  
where c.consultant_id=a.consultant_id and a.besoin_id=b.besoin_id and   
b.salarie_id=sa.salarie_id and ssa.site_id=s.site_id and s.entreprise_id=e.entreprise_id  
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MySQL多表联查的inner join方法:

select c.nom, e.nom  
from consultant c  
inner join affaire a on c.consultant_id=a.consultant_id  
inner join besoin b on a.besoin_id=b.besoin_id  
inner join salarie sa on b.salarie_id=sa.salarie_id  
inner join site s on ssa.site_id=s.site_id  
inner join entreprise e on s.entreprise_id=e.entreprise_id  
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