SELECT 
    posts.id,
    (select count(*) from post_likes where post_id = 13 and user_id = 12) as post_like
FROM
    posts
LIMIT 5

How to write this query in Laravel query builder?

CodePudding user response：

If your ORM models are defined (and you have both Post and PostLike models), create a relationship in your Post.php model (if not already), like:

public function likes(){
  return $this->hasMany(PostLike::class);
}

Then if you only need the count, try something like:

$userId = 12;

$postList = Post::query()
    ->whereId(13)
    ->withCount(['likes', 'likes AS post_like' => function ($query) use($userId) {
        $query->where('user_id', '=', $userId);
    }])
    ->limit(5)
    ->get();
// Then do something with result.
foreach ($postList as $post) {
    $count = $post['post_like'];
}

Note that above we use post_like alias, and limit to user_id, just to much OP requirements; Else we could simply set likes_count to the number of relations, like:

->withCount('likes')

But you could use relationship for subquery with the whereHas(...) eloquent method, like:

Post::query()->whereHas('likes', function($query){
  $query->where(...your statements for sub query go there);
}, '>', 4)->limit(5)->get(); //Select where more than 4 relation found with given parameters

For more see: https://laravel.com/docs/8.x/eloquent-relationships#querying-relationship-existence