db::execute PHP Method

    static function execute($sql)
    {
        $connection = self::connect();
        if (error($connection)) {
            return $connection;
        }
        // save the query
        self::$last_query = $sql;
        // execute the query
        $execute = @mysql_query($sql, $connection);
        self::$affected = @mysql_affected_rows();
        self::$trace[] = $sql;
        if (!$execute) {
            return self::error(l::get('db.errors.query_failed', 'The database query failed'));
        }
        $last_id = self::last_id();
        return $last_id === false ? self::$affected : self::last_id();
    }

 public function __set($name, $value)
 {
     $s_name = db::escape($name);
     $s_val = db::escape($value);
     $s_uid = db::escape($this->_uid);
     return db::execute("REPLACE INTO 202_config (var_name, var_value, user_id)\n                            VALUES ('{$s_name}', '{$s_val}', '{$s_uid}')");
 }