From 06cb980308f3c0d6c7807530576b0230016a15e2 Mon Sep 17 00:00:00 2001
From: Eric Lippmann <eric.lippmann@netways.de>
Date: Thu, 27 Jul 2017 15:03:12 +0200
Subject: [PATCH] Don't add GROUP BY for unjoined tables

---
 .../library/Monitoring/Backend/Ido/Query/IdoQuery.php          | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/modules/monitoring/library/Monitoring/Backend/Ido/Query/IdoQuery.php b/modules/monitoring/library/Monitoring/Backend/Ido/Query/IdoQuery.php
index d1755bf51..3a067bb3e 100644
--- a/modules/monitoring/library/Monitoring/Backend/Ido/Query/IdoQuery.php
+++ b/modules/monitoring/library/Monitoring/Backend/Ido/Query/IdoQuery.php
@@ -1152,6 +1152,9 @@ abstract class IdoQuery extends DbQuery
 
         $groupedTables = array();
         foreach ($this->groupBase as $baseTable => $aliasedPks) {
+            if (! $this->hasJoinedVirtualTable($baseTable)) {
+                continue;
+            }
             $groupedTables[$baseTable] = true;
             foreach ($aliasedPks as $aliasedPk) {
                 $group[] = $aliasedPk;