joomla 2.5中的一个模型中的多个查询

Can I do 2 separate queries in a model in joomla 2.5 ? If it is possible, how do you do this?

This is my model:

<?php
            defined('_JEXEC') or die();

            jimport( 'joomla.application.component.modellist' );

            class AnagraficheModelServiziassociatiaggiuntivi extends JModelList
            {
                           public function __construct($config = array())
                           {
                                           if (empty($config['filter_fields'])) 
                                           {
                                                           $config['filter_fields'] = array('id_servizi_aggiuntivi', 'id_persona', 'id_servizio', 'nome_servizio', 'cod_servizio', 'id_tipologia_socio', 'nome_servizio');
                                           }

                                           parent::__construct($config);
                           }

                           function getListQuery()
                           {              
                                           $db = JFactory::getDBO();
                                           $query = $db->getQuery(true);
                                           $query->select('id_servizi_aggiuntivi, id_persona , id_servizio , nome_servizio');
                                           $query->from('#__servizi_aggiuntivi as serviziaggiuntivi, #__elenco_servizi');
                                           $query->where('cod_servizio=id_servizio');
                                           $result1 = $db->loadObjectList();


                                           //$db->setQuery($query);

                                           $query = $db->getQuery(true);
                                           $query->select('id_tipologia_socio, id_servizio as cod_servizio, nome_servizio');
                                           $query->from('#__associazione_servizi as serviziassociati, #__elenco_servizi');
                                           $query->where('cod_servizio=id_servizio');
                                           $result1 = $db->loadObjectList();


                                           return $query;
                           }

                           protected function populateState($ordering = null, $direction = null)
                           {
                                           // Load the filter state.
                                           $search = $this->getUserStateFromRequest($this->context.'.filter.search', 'filter_search');
                                           $this->setState('filter.search', $search);

                                           // List state information.
                                           parent::populateState($ordering, $direction);
                           }
            }
?>

This doesn't work, but if I delete the second query it works great! In my opinion, the problem is in the function getListQuery(). In this function I want insert 2 queries not 1 query! Is it possible?

The short answer is no. getListQuery should return a query. You can't get it to return two queries.

Instead, you likely want to override the getItems function to process the items after the first query runs. You can either adjust or add items using something like the following:

public function getItems() {
    // load items from the parent getItems function, which will call getListQuery to handle your first query.
    //It only adds items if the first query works.
    if ($items = parent::getItems()) {
        $db = JFactory::getDbo();

        $query = $db->getQuery(true);
        $query->select('id_tipologia_socio, id_servizio as cod_servizio, nome_servizio');
        $query->from('#__associazione_servizi as serviziassociati, #__elenco_servizi');
        $query->where('cod_servizio=id_servizio');
        $result1 = $db->setQuery($query)->loadObjectList();

        // this is a simple way to merge the objects. You could do other processing (loops, etc) to meld the information together
        $items = (object) array_merge((array) $items, (array) $restult1);
    }
    return $items;
}