doc: adjust 9970443 for "null string"

bmomjian · bmomjian · commit 2362c2bd234f · 2014-04-22T20:33:12.000-04:00
Report by Andrew Dunstan
diff --git a/doc/src/sgml/ref/copy.sgml b/doc/src/sgml/ref/copy.sgml
@@ -490,7 +490,7 @@ COPY <replaceable class="parameter">count</replaceable>
    <para>
     <literal>FORCE_NULL</> and <literal>FORCE_NOT_NULL</> can be used
     simultaneously on the same column. This results in converting quoted
-    empty strings to null values and unquoted empty strings to empty strings.
+    null strings to null values and unquoted null strings to empty strings.
    </para>
 
  </refsect1>
