分组中取最大、最小记录

select * from orders where user_id=123 order by created_at desc limit 1

// try
Order::query()->whereRaw("id in (select min(id) from orders group by user_id)")->get();

要不要来个简单点的，减少点数据库压力的那种

查出订单表所有的用户id，然后去重 得到一个不重复的有订单的用户id数组

循环把每个用户最早的查出来，给新数组

$userIds=['123','12324'];

foreach($userIds as $userId){

       $data[$userId][]=Order::where('user_id',$userId)->latest()->first()
}

先排序然后用子查询

原生：SELECT id,user_id, min(apply_at) from orders GROUP BY user_id

DB：DB::table(‘orders’)->select(DB::raw(‘id, user_id, min(apply_at)’))->groupBy(‘user_id’)

min取最小的apply_at值，你这值肯定是时间戳吧，时间戳最小就是最早的

使用模型的查询语句：

return static::query()
            ->select('id','user_id','order_num','apply_at','expire_at')
            ->whereRaw("id in (select min(id) from sgo_orders group by user_id)")->limit(5)->get();

补充：绕过模型关联查询，使用Db的数据库查询

return DB::table('sgo_orders')
            ->select('id','user_id','order_num','apply_at','expire_at')
            ->whereRaw("id in (select min(id) from sgo_orders group by user_id)")
            ->limit(10)
            ->get()