Laravel ORM关系在Laravel 5.2上返回null

Question

I have two models User and UserType declared as follows:

class User extends Model {
    protected $table = 'user';
    protected $primaryKey = 'user_id';

    public function company() {
        return $this->hasOne('App\Models\Company', 'company_id', 'company_id');
    }

    public function userType() {
        return $this->hasOne('App\Models\UserType', 'user_type_id', 'user_type_id');
    }
}

class UserType extends Model {
    protected $table = 'user_type';
    protected $primaryKey = 'user_type_id';
}

Now, I query the relationships using:

User::with('userType', 'company')->all()

Strangely, I get the company but userType is always null. The MySQL query log shows that Laravel was able to get the user_type record.

The only difference between company and userType relationships are the data type of the primary keys. company.company_id is numeric while user_type.user_type_id is a string. I think it is related to the data type of the keys however, I have a similar setup on Laravel 5.1 and it runs perfectly.

Answer 1

Laravel supports non-numeric primary keys but you need to set:

public $incrementing = false;

on your model class. I corrected the issue by changing UserType definition to:

class UserType extends Model {
    protected $table = 'user_type';
    protected $primaryKey = 'user_type_id';
    public $incrementing = false;
}