diff --git a/doc/src/sgml/xfunc.sgml b/doc/src/sgml/xfunc.sgml
index 9de7ccc2582..9c15950ccda 100644
--- a/doc/src/sgml/xfunc.sgml
+++ b/doc/src/sgml/xfunc.sgml
@@ -1954,6 +1954,11 @@ memcpy(destination->data, buffer, 40);
          <entry><type>AbsoluteTime</type></entry>
          <entry><filename>utils/nabstime.h</filename></entry>
         </row>
+        <row>
+         <entry><type>bigint</type> (<type>int8</type>)</entry>
+         <entry><type>int64</type></entry>
+         <entry><filename>postgres.h</filename></entry>
+        </row>
         <row>
          <entry><type>boolean</type></entry>
          <entry><type>bool</type></entry>