我有两个表:
id_c name surname
1 frank pulio
2 mark adam
3 peter norton
id_v id_c data_visited note
1 1 2013-10-12 first visited to frank
2 1 2013-10-16 second visited to frank
3 2 2013-10-15 first visited to mark
4 1 2013-10-20 third visited to frank
5 2 2013-10-18 second visited to mark
我会获取带有上次访问数据的客户名称并注明。
例子:
id_c name data_visited note
1 frank 2013-10-20 third visited to frank
2 mark 2013-10-18 second visited to mark
最佳答案
SELECT t1.`id_c`,c.`name`,t1.latest,t1.`note` FROM `tablea`c
INNER JOIN
(
SELECT t2.`id_c`,t2.latest,t3.`note` from `tableb` t3
INNER JOIN
(SELECT `id_c`,MAX(`data_visited`) AS latest from
`tableb`
GROUP BY(`id_c`))t2
ON (t3.`id_c`=t2.`id_c`) AND (t3.`data_visited`=t2.latest)
)t1
ON(c.`id_c`=t1.`id_c`)
关于一行一对多的mysql，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20542601/