use strict;
use warnings;
use DBI;
my $dbh = DBI->connect('dbi:mysql:krb','mortis','');
die $DBI::errstr unless $dbh;

if (@ARGV) {
  my $img_file = 'test.jpg';
  my $img_data = getFile($img_file);

  my $sql = 'INSERT INTO foo (data) VALUES (?)';
  unless ($dbh->do($sql,undef,$img_data)) {
    die "Error executing sql: '$sql' : $DBI::errstr : ",$dbh->errstr,"\n";
  }
  print "DATA INSERTED\n";
}

my $resultSet = $dbh->selectall_arrayref('SELECT * FROM foo');
my $imgData = $resultSet->[0]->[0];
writeFile('test2.jpg',$imgData);
$dbh->disconnect;

sub getFile {
  my($file) = @_;
  my $fh;
  unless (open $fh, "<", $file) {
    die "Error opening $file : $!\n";
  }
  my $data;
  { local $/ = undef; $data = <$fh>; }
  close $fh;
  return $data;
}

sub writeFile {
  my($file,$data) = @_;
  my $fh;
  unless (open $fh, ">", $file) {
    die "Error opening $file : $!\n";
  }
  print $fh $data;
  close $fh;
}