public static function findByProvider($provider, $identifier)
    {
        $t = UserRemoteIdentity::tableName();

        return self::find()
            ->leftJoin($t, self::tableName().'.[['.self::primaryKey()[0].']]='.$t.'.[[user_id]]')
            ->andWhere($t.'.[[provider]]=:provider', [':provider' => $provider])
            ->andWhere($t.'.[[identifier]]=:identifier', [':identifier' => $identifier])
            ->one();
    }