From 83a6e85b5db4e4b59950cdc6edea1151de4dcf8a Mon Sep 17 00:00:00 2001
From: Eric Lippmann <eric.lippmann@netways.de>
Date: Fri, 22 May 2015 13:53:57 +0200
Subject: [PATCH] lib: Don't render empty filters to SQL

Else we are presented with syntax errors.

fixes #9211
---
 library/Icinga/Data/Db/DbQuery.php | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/library/Icinga/Data/Db/DbQuery.php b/library/Icinga/Data/Db/DbQuery.php
index 45a586b9a..4fa7f132d 100644
--- a/library/Icinga/Data/Db/DbQuery.php
+++ b/library/Icinga/Data/Db/DbQuery.php
@@ -166,10 +166,12 @@ class DbQuery extends SimpleQuery
                         $parts[] = $filterPart;
                     }
                 }
-                if ($level > 0) {
-                    $str .= ' (' . implode($op, $parts) . ') ';
-                } else {
-                    $str .= implode($op, $parts);
+                if (! empty($parts)) {
+                    if ($level > 0) {
+                        $str .= ' (' . implode($op, $parts) . ') ';
+                    } else {
+                        $str .= implode($op, $parts);
+                    }
                 }
             }
         } else {