- list($inusercourses, $inusercoursesparams) = $DB->get_in_or_equal($usercourses, SQL_PARAMS_NAMED);
- $subqueryconditions[] = "(ev.groupid = 0 AND ev.courseid $inusercourses)";
- $subqueryparams = array_merge($subqueryparams, $inusercoursesparams);
+ $subquerycourses = array_merge($subquerycourses, $usercourses);
+ // Make sure we remove duplicate values.
+ $subquerycourses = array_unique($subquerycourses);
+ }
+
+ // Set subquery filter condition for the courses.
+ if (!empty($subquerycourses)) {
+ list($incourses, $incoursesparams) = $DB->get_in_or_equal($subquerycourses, SQL_PARAMS_NAMED);
+ $subqueryconditions[] = "(ev.groupid = 0 AND ev.courseid $incourses)";
+ $subqueryparams = array_merge($subqueryparams, $incoursesparams);