Displaying Search results in a random order

Question

I need to display the products on the search results page in a random order. Since there is no official explanation on how to do this, I tried to edit the Mage_CatalogSearch_Model_Resource_Fulltext module, but I could't figure out where to add a ORDER BY RAND() in the prepareResults() function. Does anyone know how to achieve this?

Answer 1

Ordering actually happens in app/code/core/Mage/CatalogSearch/Model/Resource/Fulltext/Collection.php You can change ::setOrder() to look like this in order to always sort randomly – regardless of the sort attribute selected by the user:

public function setOrder($attribute, $dir = 'desc')
{
    /* ORIGINAL CODE
    if ($attribute == 'relevance') {
        $this->getSelect()->order("relevance {$dir}");
    } else {
        parent::setOrder($attribute, $dir);
    }
    */

    // RANDOM SORT INSTEAD
    $this->getSelect()->getAdapter()->orderRand($this->getSelect());

    return $this;
}

Bear in mind that you're changing a core file so for real world code you should consider creating a custom module. You can e.g. listen to the catalog_block_product_list_collection event and modify the collection sort in an observer if applicable.