diff --git a/reference/pgsql/functions/pg-lo-import.xml b/reference/pgsql/functions/pg-lo-import.xml
index 0142434c70..5dd9b2619e 100644
--- a/reference/pgsql/functions/pg-lo-import.xml
+++ b/reference/pgsql/functions/pg-lo-import.xml
@@ -13,7 +13,7 @@
    <type>int</type><methodname>pg_lo_import</methodname>
    <methodparam choice="opt"><type>resource</type><parameter>connection</parameter></methodparam>
    <methodparam><type>string</type><parameter>pathname</parameter></methodparam>
-   <methodparam><type>mixed</type><parameter>object_id</parameter></methodparam>
+   <methodparam choice="opt"><type>mixed</type><parameter>object_id</parameter></methodparam>
   </methodsynopsis>
   <para>
    <function>pg_lo_import</function> creates a new large object