diff --git a/core/modules/system/tests/modules/database_test/lib/Drupal/database_test/Controller/DatabaseTestJsonController.php b/core/modules/system/tests/modules/database_test/lib/Drupal/database_test/Controller/DatabaseTestJsonController.php
index 388a838..4a5654a 100644
--- a/core/modules/system/tests/modules/database_test/lib/Drupal/database_test/Controller/DatabaseTestJsonController.php
+++ b/core/modules/system/tests/modules/database_test/lib/Drupal/database_test/Controller/DatabaseTestJsonController.php
@@ -42,11 +42,17 @@ public function evenPagerQuery() {
       ->extend('Drupal\Core\Database\Query\PagerSelectExtender')
       ->limit($limit);
 
-    $names = $query->execute()->fetchCol();
+    $result = $query->execute();
 
-    return new JsonResponse(array(
-      'names' => $names,
-    ));
+    if ($result) {
+      $names = $result->fetchCol();
+      return new JsonResponse(array(
+        'names' => $names,
+      ));
+    }
+    else {
+      return new JsonResponse();
+    }
   }
 
   /**
@@ -66,11 +72,17 @@ public function oddPagerQuery() {
       ->extend('Drupal\Core\Database\Query\PagerSelectExtender')
       ->limit($limit);
 
-    $names = $query->execute()->fetchCol();
+    $result = $query->execute();
 
-    return new JsonResponse(array(
-      'names' => $names,
-    ));
+    if ($result) {
+      $names = $result->fetchCol();
+      return new JsonResponse(array(
+        'names' => $names,
+      ));
+    }
+    else {
+      return new JsonResponse();
+    }
   }
 
   /**