由于关系，Laravel更新模型失败

I have a situation where I fetch a model in Laravel. Something like this:

$user = User::with('subscription')->where('id', '=', 123)->first();

If I then later try and do something like this:

$user->firstname = 'John';
$user->save();

I get an SQL error because it says that there is no DB field called "subscription" It seems like the relationship is being treated as a DB field when saving. Is that right? Am I mean to

unset($user->subscription)

before saving?

Is it not possible to update a model if there is a relationship attached? Does it have to be removed before saving?

I found what was causing this. In a previous place in my code I was trying to update the relationship. Accidentally I was assigning the subscription as an attribute to my user object. This was not a Laravel issue.

try this

create new user object

$user = new User;
$user->firstname = 'John';
$user->save();

Same code is working for me. What laravel version are you using?

    $psc = Subject::with('group')->where('group_id', 1)->first();

    $psc->group->name = 'PSC';
    $psc->group->save();
    dd($psc->group);

    $psc->name = 'Science';
    $psc->save();
    dd($psc->name);