diff --git a/mod/forum/lib.php b/mod/forum/lib.php
index 0953d997e46..1ff1f88aa0d 100644
--- a/mod/forum/lib.php
+++ b/mod/forum/lib.php
@@ -6811,16 +6811,20 @@ function forum_reset_userdata($data) {
         $types       = array();
     } else if (!empty($data->reset_forum_types)){
         $removeposts = true;
-        $typesql     = "";
         $types       = array();
+        $sqltypes    = array();
         $forum_types_all = forum_get_forum_types_all();
         foreach ($data->reset_forum_types as $type) {
             if (!array_key_exists($type, $forum_types_all)) {
                 continue;
             }
-            $typesql .= " AND f.type=?";
             $types[] = $forum_types_all[$type];
-            $params[] = $type;
+            $sqltypes[] = $type;
+        }
+        if (!empty($sqltypes)) {
+            list($typesql, $typeparams) = $DB->get_in_or_equal($sqltypes);
+            $typesql = " AND f.type " . $typesql;
+            $params = array_merge($params, $typeparams);
         }
         $typesstr = get_string('resetforums', 'forum').': '.implode(', ', $types);
     }