diff --git a/lib/datalib.php b/lib/datalib.php
index af096d4baf3..2a96bae76be 100644
--- a/lib/datalib.php
+++ b/lib/datalib.php
@@ -1238,7 +1238,7 @@ function get_categories($parent='none', $sort=NULL, $shallow=true) {
                 JOIN {$CFG->prefix}context ctx
                   ON cc.id=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSECAT."
                 JOIN {$CFG->prefix}course_categories ccp
-                     ON (cc.path LIKE ".sql_concat('ccp.path',"'%'").")
+                     ON ((cc.parent=ccp.id) OR (cc.path LIKE ".sql_concat('ccp.path',"'/%'")."))
                 WHERE ccp.id=$parent
                 $sort";
     }