Retrieving objects based on exact relationships

[njutn95]

Hi all,

I have the following structure:

class User
{
    /**
     * @ORM\ManyToMany(targetEntity="App\Entity\Book", inversedBy="users")
     */
    private $books;
}

class Book
{
    /**
     * @ORM\ManyToMany(targetEntity="App\Entity\User", mappedBy="users")
     */
    private $users;
}

What I'm trying to achieve is to select all users that have books 1, 3, 7. But not select users that have books 1, 7 or those that have 1, 3, 7, 10. In other words, I'm trying to do an exact match. My current solution is to select all users, and then loop through them to filter like:

array_filter($users, fn ($user) => empty(array_diff($user->getBooks()->toArray(), $booksToMatch))
            && empty(array_diff($booksToMatch, $users->getBooks()->toArray())));

But it's far from optimal with large sets, so I'm looking at how to offload that part to the database.