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Hi , i have 4 tables
courses
students
teachers
course_student
courses has relation with students many to many throw course_student and i named this relation as subscription
#Courses Model
public function subscriptions()
{
return $this->belongsToMany(Student::class,'course_student','course_id');
}
and teacher has relation with courses throw teacher_id column that inside the courses table
#Teacher Model
public function courses() {
return $this->hasMany(Course::class);
}
Now i want to get all students for each teacher at his dashboard so i try with
public function students(): HasManyThrough
{
return $this->hasManyThrough(Student::class, Course::class, 'teacher_id', 'id');
}
and there's wrong data i collect from this relation , so i decided to make at as regular method like
public function students(): \Illuminate\Support\Collection
{
return collect($this->courses)->flatMap(function ($course){
return collect($course->subscriptions);
})->unique('id');
}
/**
flatmap to get all students at one collection cause regular map 'll create a collection for each course and each collection 'll has all students inside , and unique to filter all students and get the unique cause may the student has subscription at 2 or 3 courses for same teacher ,
*/
and now everything work correctly , but idk if this a laravel way or best practice or even clean code , so any recommendation ?
@mahmoudadelali I believe you can do that also:
Teacher.php model:
public function students()
{
return $this->belongsToMany(
Student::class,
'course_student', // Intermediate table
'course_id', // Foreign key on course_student table...
'student_id', // ...linking to students table
'id', // Local key on teachers table...
'teacher_id' // ...linking to course table
)->distinct();
}
Now i want to get all students for each teacher at his dashboard
all students irrespective of what course?
Yes, from what I know, in Laravel, there's no way to define a hasManyThrough relationship between hasMany and belongsToMany.
The closest to that is a package hasManyDeep, but in its docs, I found only ManyToMany → HasMany, not the other way around HasMany → ManyToMany like in your case.
So your code is ok, apart from the fact that you don't need the collect() in the beginning:
public function students(): \Illuminate\Support\Collection
{
return $this->courses->flatMap(function ($course){
return collect($course->subscriptions);
})->unique('id');
}
@PovilasKorop Thank you, that's reassuring
Why not use simple SQL?
return collect(Student::hydrate(DB::query('usual SQL query here')));
@PovilasKorop Cause i use eloquent why i need to use queries with-it ?
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