mysql三表联合查询,结果集合并

参考:

mysql 结果集去重复值并合并成一行

SQL 三表联查

数据库三表连接查询怎么做

合并:

MySQL中group_concat函数

完整的语法如下:

group_concat([DISTINCT] 要连接的字段 [Order BY ASC/DESC 排序字段] [Separator '分隔符'])

三表联查:

例:

有三个表 a b c
c.aid对应a.aid
c.bid对应b.bid
select  a.aname, b.bname, c.cname  from  c  
inner join a on c.aid=a.aid inner join b on c.bid=b.bid
 
select a.anme, b.bname, c.value
from a,b,c
where a.aid = c.aid and b.bid = c.bid
实战:
select b.id,GROUP_CONCAT(a.m_name SEPARATOR' '),b.b_name from t_medicinal_info a, t_product_base b, t_medicinal_productbase c 
where a.id=c.t_medicinal_id and b.id=c.t_product_base_id group by b.id

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转载自www.cnblogs.com/flypig666/p/11788391.html