Laravel (5.3) Eloquent - Relationship issue - php

Question

I have the following 3 tables which are normalised:
`Table: TheMovies`
id | MovieName
---------------------
1 | Zootopia
2 | Moana
3 | Toy Story
`Table: TheGenres`
id | GenreName
---------------------
21 | Action
22 | Animation
23 | Adventure
`Table: mMoviesGenres`
movieID | genreID
---------------------
1 | 21
1 | 23
2 | 22
2 | 21
3 | 23
3 | 21
As you can see in the 3rd table a movie has multiple genres, and a genre has multiple movies.
I've created TheMovies and TheGenres models in laravel.
I made sure that the relationship is made inside the models using the following code:
class TheMovies extends Model
{
public function TheGenres() {
return $this->belongsToMany('App\TheGenres', 'mMoviesGenres', 'seriesID', 'genreID');
}
}
class TheGenres extends Model
{
public function TheGenres() {
return $this->belongsToMany('App\TheMovies', 'mMoviesGenres', 'genreID', 'seriesID');
}
}
I've tested everything, and I succeeded displaying a list of genres for a particular movie, and I also succeeded displaying a list of movies for a particular genre.
The actual problem is that I want to display related movies for a particular movie based on genre.
Let's take TheMovies.id = 1 which is similar with TheMovies.id = 3, they are both Action and Adventure as you can see in the third table.
I've found out the query which is needed based on the following post:
SQL Query based on other table.
SELECT m2.movieId
FROM mMoviesGenres m1
INNER JOIN mMoviesGenres m2
ON m1.genreID = m2.genreID
WHERE m1.movieId = 1 AND
m2.movieId <> 1
GROUP BY m2.movieId
HAVING COUNT(*) >= 2
But I don't know how to transform this query in Eloquent style, and yes I can make a raw query in Eloquent, but I want to make use of the relationship created.
Please give me some advice.

Answer 1

You can try as:
// returns array of genre_ids associate with the TheMovies.id => 1
$genre_ids = TheGenres::whereHas('TheMovies', function($q) {
$q->where('id', 1);
})->pluck('id')->toArray();
Then use those $genre_ids to fetch the related movies as:
TheMovies::whereHas('TheGenres', function($q) use($genre_ids) {
$q->whereIn('id', $genre_ids);
})->get();
Update
Assuming you have:
$genre_ids = [21, 23];
then your query can be as:
TheMovies::whereHas('TheGenres', function($q) use($genre_ids) {
$q->whereIn('genreID', $genre_ids)
->groupBy('movieID')
->havingRaw('COUNT(DISTINCT genreID) = 2');
})->get();
Note - I have not tested it but you can give it a try.