Pagekit\Database\Query\QueryBuilder::addPart PHP Метод

    public function addPart($name, $parts)
    {
        if (is_array($this->parts[$name]) && !is_array($parts)) {
            $parts = [$parts];
        }
        if (in_array($name, ['select', 'set', 'order', 'group'])) {
            $this->parts[$name] = array_merge($this->parts[$name], $parts);
        } else {
            if (is_array($this->parts[$name])) {
                $this->parts[$name][] = $parts;
            } else {
                $this->parts[$name] = $parts;
            }
        }
        return $this;
    }