Laravel 5.1 How do you create a MySQL stored procedure with migration

Hello I'm trying to create a stored procedure using Laravel 5.1 migrations. So far I tried with DB::connection()->getPdo()->exec(), DB::raw() and DB::unprepared(), but no luck. Here's how my code looks like:

use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;
use Wryttnapp\Models\User;


class AddCentroidFieldsToUsersTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        DB::connection()->getPdo()->exec("
            ALTER TABLE `users` 
            ADD COLUMN centroid POINT NULL 
            AFTER `avatar`;");

        DB::unprepared("SET @OLD_SQL_MODE=@@SQL_MODE;

            DELIMITER ;;

            DROP PROCEDURE IF EXISTS UPDATE_USER_CENTROID;;

            CREATE PROCEDURE UPDATE_USER_CENTROID(userId INT)
              NOT DETERMINISTIC
            BEGIN
              DECLARE bDone INT;

              DECLARE tempLatLon VARCHAR(100);
              DECLARE counter INT;
              DECLARE firstLatLon VARCHAR(100);
              DECLARE polygonDefinition TEXT;
              DECLARE geometry POINT;

              DECLARE curs CURSOR FOR SELECT DISTINCT CONCAT(`latitude`, ' ', `longitude`) FROM `user_locations` WHERE `user_id` = userId ORDER BY `id` ASC;
              DECLARE CONTINUE HANDLER FOR NOT FOUND SET bDone = 1;

              OPEN curs;

              SET bDone = 0;
              SET counter = 0;
              SET polygonDefinition = ',';
              FETCH curs INTO tempLatLon;

              WHILE NOT bDone DO
                SET polygonDefinition = CONCAT(polygonDefinition, ',', tempLatLon);

                IF counter = 0 THEN
                      SET firstLatLon = tempLatLon;
                END IF;
                SET counter = counter + 1;

                FETCH curs INTO tempLatLon;
              END WHILE;

              CLOSE curs;

              SET polygonDefinition = CONCAT(polygonDefinition, ',', firstLatLon);
              SET polygonDefinition = SUBSTRING(polygonDefinition, 3);
              SET polygonDefinition = CONCAT('POLYGON((', polygonDefinition, '))');

              SET geometry = ST_Centroid(ST_GeomFromText(polygonDefinition));

              UPDATE `users` SET centroid = geometry WHERE id = userId;
            END;;

            DELIMITER ;
            ");
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        DB::connection()->getPdo()->exec("
            ALTER TABLE `users` DROP COLUMN centroid;
            DROP INDEX centroid_index ON `users`;
            DROP FUNCTION IF EXISTS `UPDATE_USER_CENTROID`;");
    }
}

Please help! Thanks!

via Chebli Mohamed