目前最新的数据能获取到,但是我想要获取关联表b最新入库时间下的数据,在根据最新入库时间返回关联表a在当前最新入库时间下的数据,没有则返回0
我自己是这样写的
select fang_time, city_name, if(area is null,0,area), if(taoshu is null,0,taoshu) from f_city as fc left join (select * from f_chengjiao order by fang_time desc) as fcj using (city_id) group by fc.city_id
我的2张关联表图
关联表a
关联表b
回复讨论(解决方案) select fang_time, city_name, if(area is null,0,area) as arra, if(taoshu is null,0,taoshu) as taoshu
from f_city as fc inner join
(select * from f_chengjiao order by fang_time desc) as fcj
using (city_id) order by fcj.fang_time desc
你要的是不是这样的,如果不是欢迎追问。
select fang_time, city_name, if(area is null,0,area) as arra, if(taoshu is null,0,taoshu) as taoshu
from f_city as fc inner join
(select * from f_chengjiao order by fang_time desc) as fcj
using (city_id) order by fcj.fang_time desc
你要的是不是这样的,如果不是欢迎追问。
你这样写全部的都出来了,并没有分组和没有新纪录的地区显示为0