From ede732c310aa0df4e2a5fdafb6e305ea98d96457 Mon Sep 17 00:00:00 2001
From: Nathan Coad <nathan+git@thecoads.com>
Date: Tue, 3 Jul 2018 23:19:32 +1000
Subject: [PATCH] handle empty variety sessions

---
 booking.variety_admin.inc | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/booking.variety_admin.inc b/booking.variety_admin.inc
index 819a2c6..8b2e11f 100644
--- a/booking.variety_admin.inc
+++ b/booking.variety_admin.inc
@@ -552,6 +552,13 @@ function booking_varietysessions_csv_report($timeslot_id) {
     WHERE p.booking_eventid = :eid ORDER BY r.rid", 
     array(':eid' => $event->eid));
   $session_members = $session_members_query->fetchAll();
+
+  // Check if we had no data added, that means there were no people in this study group
+  if (! $session_members) {
+    drupal_set_message("Error: Variety Session timeslot $timeslot_id has no members assigned.", 'error', FALSE);
+		drupal_goto('admin/booking/variety');    
+		return "";
+  }    
   
   //watchdog('booking_debug', 'booking_varietysessions_csv_report session members: <pre>@info</pre>', array('@info' => print_r( $session_members, true)));