diff --git a/main/inc/lib/sessionmanager.lib.php b/main/inc/lib/sessionmanager.lib.php
index 85376ba6a0..a1651ee60a 100755
--- a/main/inc/lib/sessionmanager.lib.php
+++ b/main/inc/lib/sessionmanager.lib.php
@@ -947,17 +947,19 @@ class SessionManager
                     FROM $workTable w
                     LEFT JOIN $workTableAssignment a
                     ON (a.publication_id = w.id AND a.c_id = w.c_id)
-                    WHERE w.c_id = %s
-                    AND parent_id = 0
-                    AND active IN (1, 0)";
+                    WHERE 
+                        w.c_id = %s AND 
+                        parent_id = 0 AND 
+                        active IN (1, 0)";
         } else {
             $sql = "SELECT count(w.id) as count
                     FROM $workTable w
                     LEFT JOIN $workTableAssignment a
                     ON (a.publication_id = w.id AND a.c_id = w.c_id)
-                    WHERE w.c_id = %s
-                    AND parent_id = 0
-                    AND active IN (1, 0)";
+                    WHERE 
+                        w.c_id = %s AND 
+                        parent_id = 0 AND 
+                        active IN (1, 0)";
 
             if (empty($sessionId)) {
                 $sql .= ' AND w.session_id = NULL ';
diff --git a/main/work/work.lib.php b/main/work/work.lib.php
index a5085d355b..c7014a1b3e 100755
--- a/main/work/work.lib.php
+++ b/main/work/work.lib.php
@@ -1335,9 +1335,10 @@ function getWorkListStudent(
         $groupInfo = GroupManager::get_group_properties($group_id);
         $groupIid = $groupInfo['iid'];
     }
+    $groupIid = (int) $groupIid;
 
     // Get list from database
-    if (!empty($group_id)) {
+    if (!empty($groupIid)) {
         $group_query = " WHERE w.c_id = $course_id AND post_group_id = $groupIid";
         $subdirs_query = "AND parent_id = 0";
     } else {
@@ -1468,6 +1469,7 @@ function getWorkListTeacher(
         $groupInfo = GroupManager::get_group_properties($group_id);
         $groupIid = $groupInfo['iid'];
     }
+    $groupIid = (int) $groupIid;
 
     $is_allowed_to_edit = api_is_allowed_to_edit() || api_is_coach();
     if (!in_array($direction, array('asc', 'desc'))) {