Display classes not in a course -ref #5619

main/inc/ajax/model.ajax.php

@@ -409,7 +409,7 @@ switch ($action) {
         $options = array('order'=>"name $sord", 'LIMIT'=> "$start , $limit");
         switch ($type) {
             case 'not_registered':                
-                $options['where'] = array(" course_id != ? " => $course_id);
+                $options['where'] = array(" (course_id IS NULL OR course_id != ?) " => $course_id);
                 $result = $obj->get_usergroup_not_in_course($options);
                 break;
             case 'registered':

main/inc/lib/usergroup.lib.php

@@ -93,8 +93,9 @@ class UserGroup extends Model {
     }
     
     public function get_usergroup_not_in_course($options = array()) {        
-        $sql = "SELECT * FROM {$this->usergroup_rel_course_table} urc
-                JOIN {$this->table} u 
+        $sql = "SELECT DISTINCT * 
+                FROM {$this->usergroup_rel_course_table} urc
+                RIGHT JOIN {$this->table} u 
                 ON (u.id = urc.usergroup_id)                
                ";              
         $conditions = Database::parse_conditions($options);