diff -u b/search_api_db/src/Plugin/search_api/backend/Database.php b/search_api_db/src/Plugin/search_api/backend/Database.php
--- b/search_api_db/src/Plugin/search_api/backend/Database.php
+++ b/search_api_db/src/Plugin/search_api/backend/Database.php
@@ -1894,7 +1894,7 @@
 
       if (empty($facet['operator']) || $facet['operator'] != 'or') {
         // All the AND facets can use the main query.
-        $select = Database::getConnection()->select($table, 't');
+        $select = $this->database->select($table, 't');
       }
       else {
         // For OR facets, we need to build a different base query that excludes