Laravel Eloquent：如何在查询而不是模型中添加属性？

Question

I need to inject into an eloquent collection some attributes coming from functions written in the model requested. As I could use the $appends attribute, but directly in the eloquent query. Something like Customer::with('orders_nb')->get() or Customer::push('orders_nb')->all() . The goal is to be able to sort them with this new column : Customer::orderBy('orders_nb)->get()

Retrieve orders_nb thanks to the ' $appends attribute :

class Customer extends Eloquent {
    protected $appends = array('orders_nb');

    public function getOrdersNbAttribute()
    {
        return $this->orders->count();  
    }
}

The problem is that I don't want to retrieve theses attributes in all of my eloquent calls. That's why I would like to inject these extra attributes in the query.

Actually I'm using a custom function to get my Customers collection with these extra data :

public static function allWithExtraAttr() {
    $foo = new Collection;
    foreach(Customer::all() as $customer) {
        $customer->orders_nb = $fonction->orders->count();
        $foo->push($fonction);
    }

    return $foo;
}

Is there a better way to do it in your opinion?

A little diagram to understand : how to add attribute at the query instead of in the model ?

Answer 1

@geertjanknapen

I've simplified my code for the explications, but there is also non-relationship functions, which aren't recognized by ::with() function :

public function getEmploisAttribute()
{
    $emplois = new Collection();
    foreach($this->fonction_sous_groupes as $fonction_sous_groupe) {
        foreach($fonction_sous_groupe->emplois as $emploi) {
            $emplois->push($emploi);
        }
    }
    return $emplois;
}