Laravel 5.2 set model attributes based on fields in Input - eloquent

Question

I have huge user update form. Sometimes update contains huge amount of fields, sometimes just one or two. This is my code:
public function updateUser(Request $request){
$user = User::where('id',$request->id)->firstOrFail();
if($request->first_name){
$user->first_name= $request->first_name;
}
if($request->last_name){
$user->last_name = $request->last_name;
}
if($request->job_name){
$user->job_name= $request->job_name;
}
//etc.. 20 more fields
$user->save();
It is possible to set model attributes dependent on fields in $request? Sometimes $request contains 1 field, sometimes 20. Please notice I want to touch database only once, using save() method at the end.

Answer 1

$user->update($request->all());
Make sure all necessary variables are specified in your $fillable array for User model
If you want to update model attributes without saving use fill method

Answer 2

If $request field name and Model field name are same(as it seems in your current code) try this:
$input = $request->all();
$user = User::firstOrFail('id',$input->id);
$updateNow = $user->update($input);
Another option is:
DB::table('users')
->where('id', $request->id)
->update($request); //or can use Input::all()
Have a look at it as well for more explanation: Query Builder

Answer 3

for User model
/**
* The attributes that are mass assignable.
*
* #var array
*/
protected $fillable = [
'name', 'email', 'password', 'facebook_id', 'job_name', '20 more fields...'
];
for Controller
public function store(Request $request){
$allRequest = $request->all();
// It is not in table
unset($allRequest['_token']);
User::create($allRequest);
}