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Home Backend Development PHP Tutorial 2个表中有相同的字段 怎么处理?

2个表中有相同的字段 怎么处理?

Jun 23, 2016 pm 01:44 PM

比如A里面有name字段,B里面也有name字段,这关联在这起怎么知道取的是那个值呢


回复讨论(解决方案)

select a.id, b.id from 表 a inner join 表 b 

表名.id

select a.name from tableA as a join tableB as b on a.id=b.id;

这样用Php查询输出怎么做啊?不是要合并表,就是输出上怎么关联这2个不同的表相同的字段

select A.name as a_name,B.name as b_name from A,B where...

有条件自己加上就是了。这样就能区分各自的字段了。

使用限定列名

select A.name  as a_name,B.name as b_name from A,B where... 

 $u->a_name;

字段前面加上“表名.”,用别称更好 alias

我刚想到,就来结贴了,果然,也有人回答了,谢谢

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