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关于mysql的查询跟页面的显示

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Jun 13, 2016 am 11:54 AM

concatmysqlnbspselect

关于mysql的查询和页面的显示
各位大神，情况是这样的，现在要从数据库读取关于产品的信息，然后一个产品可能对应着多个产地，每个产地都有产地名称，要求如果某产品有多个产地，在产品列表对应的搜索栏里能通过该产品的每一个产地名称搜索到改产品，但是在产品列表里一个产品时能显示一条记录，请问怎么实现？
------解决方案--------------------
示意
select 产品, group_concat(产地) as 产地 from 表 group by 产品

可得这样的结果
产品1 产地1,产地2,产地3
------解决方案--------------------
一个表查询有这么多join啊你这个sql语句得优化了查询相当慢把

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