https://www.php.net/manual/zh/solrquery.setfacetmissing.php
PHP: SolrQuery::setFacetMissing - Manual
Maps to facet.missing
phpmanual
https://www.php.net/manual/es/solrquery.setfacetmissing.php
PHP: SolrQuery::setFacetMissing - Manual
Mapea a facet.missing
phpmanual