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

In Laravel 5.1, using Eloquent ORM, how does one update a single attribute for every relation?

我到处找资料,就是搞不懂这个。假设我已经建立了一个具有 hasMany 关系和逆关系的模型,如下所示:

    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');
    }

}

并且我已确保某些子帐户的值与 master_account_id 列中主帐户的主 ID 相匹配。

我在我的控制器中通过 dd()ing 值测试了这种关系,如下所示:

public function edit(MasterAccount $masterAcct)
    {

        dd($masterAccount->subAccounts);

    }

这成功地 return 收集了所有相关模型。但是,我无法弄清楚如何为 belongsTo MasterAccount 的每个模型更新单个属性——难道不应该有这样的级联方式吗?我通过这样做破解了它:

<?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]);

        }
}

这行得通,但我只知道有一些 "Eloquent," 方法可以做到这一点......对吗?

根据 documentation 这应该有效:

<?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]);

        }
}