laravel query relationship to check if data exists - php

Question

I have a set up like this,
QUIZ MODEL
public function scores()
{
return $this->hasMany('App\Score');
}
SCORE MODEL
public function quiz()
{
return $this->belongsTo('App\Quiz');
}
public function user()
{
return $this->belongsTo('App\User');
}
USER MODEL
public function scores()
{
return $this->hasMany('App\Score');
}
Some background, a quiz should only be playable by a user if that user does not already have a score for said quiz, what I am wanting to do is that if a user has a relationship with a quiz via having a score I want to stop that quiz being return in the query, here is my attempt,
$quiz = Quiz::with('questions.answers')
->has('scores.user', 2)
->whereDate('date_playable', '=', $date)
->first();
However this returns no quizes regardless of whether the user has a score for it or not. Can anyone enlighten me on how to only return quizes that a user does not currently have a score for?

Answer 1

You are currently searching for a quiz that does not have more than 2 scores for any user.
What you need is whereDoesntHave instead:
$quiz = Quiz::with('questions.answers')
->whereDoesntHave('scores', function ($query) use ($user) {
$query->where('user_id', $user->id);
})
->whereDate('date_playable', '=', $date)
->first();
Where $user is the App\User instance that you are querying for.

Answer 2

There could be multiple approaches to achieve that outcome. I am thinking about creating a many to many relationship between Quizzes and Users, taking scores as the middle table.
User
{
public function quizzes()
{
return $this->belongsToMany(Quiz::class, 'scores');
}
}
Then to get the desired quiz:
$quiz = Quiz::with('questions.answers')
->whereKeyNot($user->quizzes()->pluck('id')->all())
->whereDate('date_playable', '=', $date)
->first();