Index: doc/src/sgml/ref/create_table.sgml
===================================================================
RCS file: /projects/cvsroot/pgsql/doc/src/sgml/ref/create_table.sgml,v
retrieving revision 1.94
diff -u -r1.94 create_table.sgml
--- doc/src/sgml/ref/create_table.sgml	13 Aug 2005 02:48:18 -0000	1.94
+++ doc/src/sgml/ref/create_table.sgml	31 Oct 2005 17:54:10 -0000
@@ -421,7 +421,10 @@
       primary key of the <replaceable
       class="parameter">reftable</replaceable> is used.  The
       referenced columns must be the columns of a unique or primary
-      key constraint in the referenced table.
+      key constraint in the referenced table.  Note that foreign key
+      constraints may not be defined between temporary tables and permanent
+      tables. This is because doing so would eliminate most of the performance
+      gains of using a temporary table.
      </para>
 
      <para>