#! perl -w
use CGI ':standard'; 
use GD::Graph::bars; 
use DBI;

my $SQL = "SELECT A.YM, SUM(A.TC)FROM A GROUP BY A.YM ORDER BY A.YM
";

$dbh = DBI->connect('dbi:DB2:DB2W',"$mf_id" , "$mf_pw"); if ($DBI::errstr) {print "$DBI::errstr";}
$sth = $dbh->prepare($SQL);                              if ($DBI::errstr) {print "$DBI::errstr";}
$rc  = $sth->execute;                                    if ($DBI::errstr) {print "$DBI::errstr";}
$data = $sth->fetchall_arrayref;

my $mygraph = GD::Graph::bars->new(800, 500);
$mygraph->set(      
    x_label     => 'Month',
    y_label     => 'Transactions',
    title       => 'Number of Transactions per Month',
    show_values => 1,
    bar_spacing => 10,
) or warn $mygraph->error;

my $myimage = $mygraph->plot(\@$data) or die $mygraph->error;
print "Content-type: image/png\n\n";
print $myimage->png;