diff --git a/src/GraphQL/Resolver/QueryType.php b/src/GraphQL/Resolver/QueryType.php
index 0221be41..bb89fa41 100644
--- a/src/GraphQL/Resolver/QueryType.php
+++ b/src/GraphQL/Resolver/QueryType.php
@@ -293,7 +293,7 @@ public function resolveObjectGetter($value = null, $args = [], $context = [], Re
 
         if ($isFullpathSet) {
             $fullpath = Service::correctPath($args['fullpath']);
-            $conditionParts[] = sprintf('(concat(%s, %s) =' . Db::get()->quote($fullpath) . ')',
+            $conditionParts[] = sprintf('(CONCAT(`%s`,`%s`) =' . Db::get()->quote($fullpath) . ')',
                 Service::getVersionDependentDatabaseColumnName('o_path'),
                 Service::getVersionDependentDatabaseColumnName('o_key'));
         }
@@ -423,7 +423,7 @@ static function ($fullpath) use ($db) {
                 },
                 str_getcsv($args['fullpaths'], ',', "'")
             );
-            $conditionParts[] = sprintf('(concat(%s, %s) IN (' . implode(',', $quotedFullpaths) . '))',
+            $conditionParts[] = sprintf('(CONCAT(`%s`,`%s`) IN (' . implode(',', $quotedFullpaths) . '))',
                 Service::getVersionDependentDatabaseColumnName('o_path'),
                 Service::getVersionDependentDatabaseColumnName('o_key'));
         }