diff --git a/doc/src/sgml/ref/truncate.sgml b/doc/src/sgml/ref/truncate.sgml
index c1e42376ab..0895fd17eb 100644
--- a/doc/src/sgml/ref/truncate.sgml
+++ b/doc/src/sgml/ref/truncate.sgml
@@ -123,7 +123,9 @@ TRUNCATE [ TABLE ] [ ONLY ] <replaceable class="parameter">name</replaceable> [
    scans, and the whole point is not to do one.  The <literal>CASCADE</literal>
    option can be used to automatically include all dependent tables &mdash;
    but be very careful when using this option, or else you might lose data you
-   did not intend to!
+   did not intend to!  Note in particular that when the table to be truncated
+   is a partition, cascading occurs as if the parent partitioned table is
+   truncated.
   </para>
 
   <para>