在Laravel 5.1中，使用Eloquent ORM，如何为每个关系更新单个属性？

Question

I've been searching the documents everywhere and I can't figure this one out. Suppose I have set up a model with a hasMany relationship and the inverse like this:

    class MasterAccount extends Model {

    //master_account_id exists as a foreign key in sub_account table 
    //and references primary key in master_account table as
    //defined in the migrations I set up for this
    public function SubAccounts()
    {
        return $this->hasMany('App\SubAccount');
    }

}

And I've made sure that some sub accounts have values matching the master account's primary id in the master_account_id column.

I've tested the relationship by dd()ing values in my controller like this:

public function edit(MasterAccount $masterAcct)
    {

        dd($masterAccount->subAccounts);

    }

And this does successfully return a collection of all the related models. However, I cannot figure out how I would update a single attribute for every model that belongsTo MasterAccount -- shouldn't there be a way to cascade like this? I hacked it to work by doing this:

<?php namespace App\Http\Controllers;

use App\SubAccount;

public function update(MasterAccountRequest $request, MasterAccount $masterAccount)
    {
        //current request id
        $id = $masterAccount->id;

        //cascade global value to related Accounts
        if ($request->some_value == 1)
        {
            //look more into this... ARGH!!!
            SubAccount::where('master_account_id', '=', $id)->update(['this_value' => 1]);

        }
}

And this works but I just KNOW there is some "Eloquent," way to do this.....right?

Answer 1

According to the documentation this should work:

<?php namespace App\Http\Controllers;

use App\SubAccount;

public function update(MasterAccountRequest $request, MasterAccount $masterAccount)
    {
        //current request id
        $id = $masterAccount->id;

        //cascade global value to related Accounts
        if ($request->some_value == 1)
        {
            //look more into this... Wooooot!!!
            $masterAccount->SubAccounts()->update(['this_value' => 1]);

        }
}