perl -MData::Dumper -MDBI -MDBIx::Simple -e '
  my $db1 = DBI->connect;        # (uses defaults to connect)
  my $db2 = DBIx::Simple->connect;
  use Benchmark qw( cmpthese ) ;
  my $COUNT = -20;
  print "-- COUNT [$COUNT]\n";
  cmpthese( $COUNT, {
    selectrow_arrayref => sub { my @arr = @{ $db1->selectrow_arrayref( "select i from generate_series(1,10) as f(i) where i > 5" ) }; },
    dbix_query_flat    => sub { my @arr = $db2->query( "select i from generate_series(1,10) as f(i) where i > 5")->flat; },
  });
'

-- COUNT [-20]
                     Rate    dbix_query_flat selectrow_arrayref
dbix_query_flat    5608/s                 --               -23%
selectrow_arrayref 7293/s                30%                 --