Backend\Core\Installer\ModuleInstaller::addModule PHP Method

    protected function addModule($module)
    {
        $this->module = (string) $module;
        // module does not yet exists
        if (!(bool) $this->getDB()->getVar('SELECT 1 FROM modules WHERE name = ? LIMIT 1', $this->module)) {
            // build item
            $item = array('name' => $this->module, 'installed_on' => gmdate('Y-m-d H:i:s'));
            // insert module
            $this->getDB()->insert('modules', $item);
        } else {
            // activate and update description
            $this->getDB()->update('modules', array('installed_on' => gmdate('Y-m-d H:i:s')), 'name = ?', $this->module);
        }
    }