From 9c1076338120a19750ae7e269548cbf8fefe75fd Mon Sep 17 00:00:00 2001
From: Jonathan Green <jonathan@razzard.com>
Date: Thu, 6 Sep 2018 22:43:53 -0300
Subject: [PATCH] Add conditional checking if we are working with an empty set.

---
 includes/orphaned_objects.inc | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/includes/orphaned_objects.inc b/includes/orphaned_objects.inc
index 60ddf34d..1d90b4d7 100644
--- a/includes/orphaned_objects.inc
+++ b/includes/orphaned_objects.inc
@@ -159,7 +159,7 @@ WHERE {
   # Filter by "parent" relationships
   FILTER (!dead_parent_relationships)
  
-  # Exclude objects with live parents - isMemberOf, isMemberOfCollection, isPageOf.
+  # Exclude objects with live parents
   OPTIONAL {
     !live_parent_relationships .
     ?liveparent <fedora-model:hasModel> <info:fedora/fedora-system:FedoraObject-3.0> .
@@ -170,7 +170,10 @@ WHERE {
 } ORDER BY ?object
 EOQ;
   $parent_relationships = module_invoke_all('islandora_solution_pack_child_relationships');
-
+  if (count($parent_relationships['predicate']) == 0) {
+    // No predicates to search for. Exit early.
+    return array();
+  }
   $optionals = (array) module_invoke('islandora_xacml_api', 'islandora_basic_collection_get_query_optionals', 'view');
   $filter_modules = array(
     'islandora_xacml_api',