Limiting laravel query using whereIn - laravel

Question

So i have a query to make but i don`k know how best to it.
I have 2 class like below:
User.class
class User {
function posts(){
return $this->hasMany(Post::class, 'user_id');
}
}
Post.class
class Post {
function user(){
return $this->belongsTo(User::class, 'user_id');
}
}
and in my controller i want to get posts per User with a limit for each user NOT for all results. So here is what i have this in my controller:
function getPosts(Request $request){
$user_ids = [1,2,3,4];
$posts = Post::whereIn('user_id', $user_ids)->latest()->take(10)->get();
return $posts;
}
So the above get will get me just 10 entries from all of them yet i want to get 10 for each user nomatter how many user IDs

Answer 1

You can simply limit the relationship with a sub-query:
User::with(['posts' => function($query) {
return $query->limit(10);
}]);

Answer 2

May be something like
DB::table('posts as p1')->leftJoin('posts as p2', function($join){
$join->on('p1.id', '=', 'p2.id')
})->whereIn(p1.user_id, $user_ids)->groupBy('p1.id')->having(COUNT(*) < 10)->orderBy([id, created_at]);
will work for you. for the reference question
The query was
SELECT user_comments.* FROM user_comments
LEFT OUTER JOIN user_comments user_comments_2
ON user_comments.post_id = user_comments_2.post_id
AND user_comments.id < user_comments_2.id
where user_comments.post_id in (x,x,x)
GROUP BY user_comments.id
HAVING COUNT(*) < 3
ORDER BY user_id, created_at
Roughly in DB query builder, it will be like
DB::table('user_comments as uc1')->leftJoin('user_comments as uc2', function($join){
$join->on('uc1.post_id', '=', 'uc2.post_id')->andOn(uc1.id < uc2.id);
})->whereIn(uc1.post_id, [x,x,x])->groupBy('uc1.id')->having(COUNT(*) < 3)->orderBy([user_id, created_at]);
I hope this is helpful for you and give you good idea to get it.