I installed Class::DBI , and created an "Event" object to test with. The savings in the amount of code that I had to write was tremendous:

package Event;
use base qw(Class::DBI);

# Tell Class::DBI a little about yourself
Event->table('events');
Event->columns('All', qw( name given_by location date time ) );
Event->columns('Primary', 'name');
Event->set_db('Main', 'dbi:mysql:xxx', 'xxx', 'xxx' );

1;
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#!/usr/bin/perl -w

use DBI;
use Guest;
use Event;
use Benchmark;

# Connect to database
my $dbh = DBI->connect( "dbi:mysql:web_stuff", 'xxx', 'xxx' )
   or die "Can't connect to MySQL database: $DBI::errstr\n";

# Need to benchmark these solutions
sub modify_event {
   ### Test (query) the Event object
   my $this_event = Event->retrieve('Party');

   ### Test (modify) the Event object
   $this_event->time('9:00 PM');
   $this_event->commit;
}

sub modify_guest {
   # Fetch One
   my $last_name = "Rodriguez";
   my $q_last_name = $dbh->quote($last_name);
   my $first_names = "Alex";
   my $q_first_names = $dbh->quote($first_names);

   my ($add,$city,$state,$zip,$cnt) =
      $dbh->selectrow_array( "SELECT address, city, state,
                                     zip, est_count
                              FROM   guest_list
                              WHERE  last_name = $q_last_name
                              AND    first_names = $q_first_names" 
                           );

   my $guest = new Guest ($last_name,$first_names,
                          $add,$city,$state,$zip,$cnt);

   #### Test Update
   $guest->state("TX");
   $guest->update($dbh);
}

timethese(1000, {modify_event => 'modify_event()',
                 modify_guest => 'modify_guest()'  });
$dbh->disconnect();
exit;
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Benchmark: timing 1000 iterations of modify_event, modify_guest...
modify_event:  7 wallclock secs ( 5.25 usr +  0.26 sys =  5.51 CPU)
modify_guest:  5 wallclock secs ( 2.89 usr +  0.15 sys =  3.04 CPU)
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