SolrQuery::addSortField Used to control how the results should be sorted &reftitle.description; publicSolrQuerySolrQuery::addSortField stringfield intorder Used to control how the results should be sorted. &reftitle.parameters; field The name of the field order The sort direction. This should be either SolrQuery::ORDER_ASC or SolrQuery::ORDER_DESC. &reftitle.returnvalues; Returns the current SolrQuery object.