连表查询时报错Column 'id' in field list is ambiguous，

正确的语句该怎么写，为什么

https://blog.csdn.net/z_ssyy/article/details/81706876
你两个id冲突

你2个表中都有id字段，你要指明是哪个表里面的id啊，你表加个别名啊，

select * from customer c 
left join purcase p
on c.customerid = p.customerid
where ...
group by c.customerid,c.id