Re: Document NULL

I failed to notice the comment in the preceding paragraph about t/f being manually added.  It can be removed.

 <para>
  The following <literal>CREATE TABLE</literal> and <literal>INSERT</literal>
  SQL commands can be executed in any SQL client to create and populate
  the persistent table used in the examples below.  The <literal>\pset</literal>
  commands require the use of <application>psql</application> as the client program;
  they make the resulting output a bit easier to read and do not impact any behaviors
  described herein.  The examples also omit any transactional command output when
  transactions are used.  Instead, each transaction gets its own display block.
 </para>

David J.