Three-way many-to-many relationship in Laravel

Question

I have three models that need to be related in a pivot table: User, Student, Plan. So each user can subscribe a student to a plan.

What I\'ve found so far is to crea

Answer 1

I often use another model to abstract a three-way many to many relations.

We have our relation I will call the relation relation.

The db structure:

table relations: id, user_id, student_id, plan_id

The app has the following four models:

• User
• Student
• Plan
• Relation

Here is how we connect the four models using Relationships:

User, Plan, Student:

function relations() {
   return $this->hasMany(Relation::class);
}

Relation:

function student() {
   return $this->belongsToMany(Student::class);
}

function user() {
   return $this->belongsToMany(User::class);
}

function plan() {
   return $this->belongsToMany(Plan::class);
}

You can retrieve the entities like this:

//get the plan of a student related to the user
$user->relations()->where('student_id', $student)->first()->plan();

//get all entities from the relation
foreach ($user->relations as $relation) {
    $plan = $relation->plan;
    $student = $relation->student;
}

Its the only solution I have found in all the time I have been developing on Laravel.