In docs, clarify that, without ORDER BY, the window frame is all rows in

the partition.

doc/src/sgml/syntax.sgml

@@ -1794,9 +1794,10 @@ UNBOUNDED FOLLOWING
     window functions that act on the frame instead of the whole partition.
     The default framing option is <literal>RANGE UNBOUNDED PRECEDING</>,
     which is the same as <literal>RANGE BETWEEN UNBOUNDED PRECEDING AND
-    CURRENT ROW</>.  This sets the frame to be all rows from the partition start
-    up through the current row's last peer as specified by <literal>ORDER BY</>,
-    or all partition rows if there is no <literal>ORDER BY</>.
+    CURRENT ROW</>.  With <literal>ORDER BY</>, this sets the frame to
+    be all rows from partition start up through the current row's
+    last peer.  Without <literal>ORDER BY</>, all partition rows are
+    included in the window frame.
    </para>
 
    <para>