diff --git a/node_reference/node_reference.module b/node_reference/node_reference.module
index 733dbda..0c569ad 100644
--- a/node_reference/node_reference.module
+++ b/node_reference/node_reference.module
@@ -1095,7 +1095,11 @@ function node_reference_field_views_data($field) {
   // views/modules/field.views.inc, which is where that function is defined.
   $data = field_views_field_default_views_data($field);
 
-  $storage = $field['storage']['details']['sql'];
+  if (isset($field['storage']['details']['sql'])) {
+    $storage = $field['storage']['details']['sql'];
+  } else {
+    return $data;
+  }
 
   foreach ($storage as $age => $table_data) {
     $table = key($table_data);