delete from `data` where `id` not in (
select t.max_id from
(select max(`id`) as max_id from `data` group by `title`) as t
);
data表里面的title重复删除只軣最大ID一个数据
(select max(`id`) as max_id from `data` group by `title`,`content`
这里的,`content`多个重复就这样