Level 6
I forgot to say that all user types share the tame departments.
Each user type can be part of any department.
But as I said, a person has just one user type and one department at the same time.
Jan 6, 2015
8
Level 6
Relationship problem
Hi all, I need your help!
Given I have some user types: teacher, students, workers and some departments: A, B, C.
One person is in one department and has one user type.
Now I want to create a blog post which all teachers from department A and students from B and C should see.
How do I setup and store and setup these relations?
I thought about a pivot table which holds the news_id, usertype_id and the department_id.
And to get all posts for a person maybe a call like this:
Post::teacher($department_id)->all()
But it would be great if I still could use the sync, detach, etc. methods to interact with the data.
Do you have any advice?
Just ask if you need more details :)
Level 4
My wife says I should never give relationship advice.
2 likes
Level 6
but maybe eloquent adice? :)
Level 6
Maybe Post::teacher($department_id)->all() is to hard.
I have a repository. so maybe the call would be like $this->repo->filtered($usertype_id, $department_id)
I think the tables should look something like this:
Table: news
id title body
1 My Post My Post Body
Table: usertypes
id name
1 teacher
2 student
3 worker
Table: departments
id name
1 A
2 B
3 C
Table: news_relations
id news_id usertype_id department_id
1 1 2 2
2 1 1 1
But I have still no idea how to set up the relations and queries.
Level 56
I can't wrap my head around your problem. Triple sided relationships are always hard to manage (in real life too @SP1966 ;) ).
You can try to introduce another model which has no real life meaning but which can turn your problem in a classical two sided relationship.
Level 6
For all who have the same problem, that's my solution:
Models
// Usertype Model
class Usertype extends \Eloquent {
//...
public function news()
{
$model = $this->belongsToMany('News', 'news_relations')->withPivot('department_id');
if($this->department_id) $model->wherePivot('department_id', '=', $this->department_id);
return $model;
}
}
// Department Model
class Department extends \Eloquent {
//...
public function usertypes()
{
return $this->belongsToMany('Usertype', 'news_relations')->withPivot('news_id');
}
public function news()
{
return $this->belongsToMany('News', 'news_relations')->withPivot('usertype_id');
}
}
// News Model
class News extends \Eloquent {
//...
public function departments()
{
return $this->belongsToMany('Department', 'news_relations')->withPivot('usertype_id');
}
}
Usage
Get all news for a specific department and all user types
Department::first()->news
Get all news for a specific user type and all departments
Usertype::first()->news
Get all news for a specific user type and department
Department::find(2)->usertypes()->find(2)->news
Add new relations
$relations = [
['department_id' => 2, 'usertype_id' => 2],
['department_id' => 1, 'usertype_id' => 2],
['department_id' => 3, 'usertype_id' => 3],
];
News::find(2)->departments()->sync($relations);
Level 56
Clever idea with the wherePivot
Level 6
@JeffreyWay Maybe that's something for you eloquent series. just ignore my tries to solve that problem.
Please or to participate in this conversation.