(PECL solr >= 0.9.2)
SolrQuery::addSortField — Used to control how the results should be sorted
$field
[, int $order = SolrQuery::ORDER_DESC
] ) : SolrQueryUsed to control how the results should be sorted.
fieldThe name of the field
orderThe sort direction. This should be either SolrQuery::ORDER_ASC or SolrQuery::ORDER_DESC.
Returns the current SolrQuery object.