mysql获取关联表下最新数据

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