diff --git a/classes/condition/studentquiz_condition.php b/classes/condition/studentquiz_condition.php
index 10cf7ac0..cbc878bb 100755
--- a/classes/condition/studentquiz_condition.php
+++ b/classes/condition/studentquiz_condition.php
@@ -139,11 +139,13 @@ protected function init() {
     }
 
     private function get_special_sql($sqldata, $name) {
-        if (substr($sqldata, 0, 12) === 'mydifficulty') {
-            return str_replace('mydifficulty', 'ROUND(1 - (sp.correctattempts / sp.attempts),2)', $sqldata);
-        }
-        if ($name == "onlynew") {
-            return str_replace('myattempts', 'sp.attempts', $sqldata);
+        if ($this->studentquiz->aggregated) {
+            if (substr($sqldata, 0, 12) === 'mydifficulty') {
+                return str_replace('mydifficulty', 'ROUND(1 - (sp.correctattempts / sp.attempts),2)', $sqldata);
+            }
+            if ($name == "onlynew") {
+                return str_replace('myattempts', 'sp.attempts', $sqldata);
+            }
         }
         return $sqldata;
     }