diff --git a/reference/dba/functions/dba-key-split.xml b/reference/dba/functions/dba-key-split.xml
index 3b54051ef3..c6ec697a1a 100755
--- a/reference/dba/functions/dba-key-split.xml
+++ b/reference/dba/functions/dba-key-split.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- $Revision$ -->
-<!-- EN-Revision: 9c4c9718261c2705fef2a490e3926751134aec32 Maintainer: takagi Status: ready -->
+<!-- EN-Revision: d34561113baaf49e9d0539c46511242941ea5a7b Maintainer: takagi Status: ready -->
 <refentry xml:id="function.dba-key-split" xmlns="http://docbook.org/ns/docbook">
  <refnamediv>
   <refname>dba_key_split</refname>
@@ -43,6 +43,30 @@
    この関数は &false; を返します。
   </para>
  </refsect1>
+
+ <refsect1 role="changelog">
+  &reftitle.changelog;
+  <informaltable>
+   <tgroup cols="2">
+    <thead>
+     <row>
+      <entry>&Version;</entry>
+      <entry>&Description;</entry>
+     </row>
+    </thead>
+    <tbody>
+     <row>
+      <entry>8.4.0</entry>
+      <entry>
+        <parameter>key</parameter> に &null; または 
+        &false; を渡すことは、非推奨となりました。
+      </entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </informaltable>
+ </refsect1>
+
  <refsect1 role="seealso">
   &reftitle.seealso;
   <para>