diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml
index 0b3e6308d56..4b474c13917 100644
--- a/doc/src/sgml/catalogs.sgml
+++ b/doc/src/sgml/catalogs.sgml
@@ -4181,6 +4181,19 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
       </para></entry>
      </row>
 
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>fdwconnection</structfield> <type>oid</type>
+       (references <link linkend="catalog-pg-proc"><structname>pg_proc</structname></link>.<structfield>oid</structfield>)
+      </para>
+      <para>
+       References a connection function that is responsible for creating a
+       connection string for a subscription when the subscription uses a
+       server based on this foreign-data wrapper. Zero if this foreign-data
+       wrapper does not support subscription connections.
+      </para></entry>
+     </row>
+
      <row>
       <entry role="catalog_table_entry"><para role="column_definition">
        <structfield>fdwacl</structfield> <type>aclitem[]</type>
@@ -8714,12 +8727,22 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
       </para></entry>
      </row>
 
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>subserver</structfield> <type>oid</type>
+       (references <link linkend="catalog-pg-foreign-server"><structname>pg_foreign_server</structname></link>.<structfield>oid</structfield>)
+      </para>
+      <para>
+       Foreign server to use for the connection string. Zero if <structfield>subconninfo</structfield> is nonnull.
+      </para></entry>
+     </row>
+
      <row>
       <entry role="catalog_table_entry"><para role="column_definition">
        <structfield>subconninfo</structfield> <type>text</type>
       </para>
       <para>
-       Connection string to the upstream database
+       Connection string to the upstream database. <literal>NULL</literal> if <structfield>subserver</structfield> is nonzero.
       </para></entry>
      </row>