concat column data in sql laravel

//must have
use Illuminate\Support\Facades\DB;

Model::select(DB::Raw("CONCAT(profiles.first_name, ' ', profiles.last_name) AS name"))->get();

//concat other table data and display as one line with ',' as a delimiter
//DB::Raw("(SELECT GROUP_CONCAT(a.contact_number) FROM contacts as a JOIN users as b ON a.user_id = b.user_id WHERE a.user_id = users.user_id) AS contact")
//expected output would be 09123456789,09876543210,09000000000