How to convert this to a nice Eloquent query - php

Question

How to query with Eloquent, all users without a certain type of certificate?
Laravel 4
I've got 2 tables:
users table:
->id
->name
certificats table:
->id
->user_id
->certificate_type
I`m struggling with this for hours now. Last thing i tried was:
$users = User::with(array('certificate' => function($query)
{
$query->where('type','!=','SL');
}))->get();
This gives me all the users, but i was trying to get all the users without certificate type 'SL'.
-- edit:
Spencer7593's raw query below works. But i`m not getting the eloquent query to work.
SELECT u.*
FROM users u
LEFT
JOIN certificates c
ON c.user_id = u.id
AND c.type = 'SL'
WHERE c.user_id IS NULL
The relationship:
public function certificate(){
return $this->hasMany('Certificate');
}
public function certificate(){
return $this->belongsTo('User');
}

Answer 1

The SQL to get the result set you want is fairly simple.
SELECT u.*
FROM users u
LEFT
JOIN certificates c
ON c.user_id = u.id
AND c.type = 'SL'
WHERE c.user_id IS NULL
That's a familiar pattern called an "anti-join". Basically, it's a LEFT JOIN look for matching rows, along with rows from users that don't have a match, and then filter out all rows that did get a match, and we're left with rows from users that don't have match.
The trick is going to be getting Eloquent to generate that SQL for you. To get Eloquent to do that, you need to tell eloquent to do a LEFT JOIN, and add a WHERE clause,
maybe something like this would be close:
->left_join('certificate AS c', function($join){
$join->on('c.user_id','=','user.id');
$join->and_on('c.type','=','SL');
})
->where_null('c.user_id')
FOLLOWUP
(For the benefit of those who might not read the comments)
Klass Terst (OP), reports syntax problems in the attempt at Eloquent (in the answer above): left_join needed to be replaced with leftJoin, and the and_on wasn't recognized. (The latter may have been my invention, based on the convention used in with where, and_where, or_where.)
$users = DB::table('users')
->select('users.id','users.name')
->leftJoin('certificate AS c', function($join){
$join->on('c.user_id','=','user.id');
$join->on('c.type','=','SL');
})
->where_null('c.user_id');

Answer 2

I believe the problem is in your relationships.
Models
class User extends Eloquent
{
public function certificates()
{
return $this->hasMany('Certificate');
}
}
class Certificate extends Eloquent
{
public function user()
{
return $this->belongsTo('User');
}
}
Controller
$users = User::with(array('certificates' => function($query)
{
$query->where('type','!=','SL');
}))->get();
return View::make('yourView')->with('users',$users);
View
#foreach($users as $user)
{{ $user->name }} // User's name
#foreach($user->certificates as $certificate)
{{ $certificate->certificate_type }} // Certificate type shouldn't be 'SL'
#endforeach
#endforeach
I hope this helps!