use strict;
use warnings;
use XML::Twig;

my $xfile = <<'EOF';
<?xml version="1.0" encoding="UTF-8"?>
<results>
<document id="\2006\200601\20060125\20060125_18.txt"
            datetime="2006/01/25"
            sourcecategory="News Archive"
            schemeversion="1.1">


  </document>
  <document id="\2006\200601\20060125\20060125_19.txt"
            datetime="2006/01/25"
            sourcecategory="News Archive"
            schemeversion="1.1">

  <record>
    <sentence-number>3</sentence-number>
    <data-class>Target</data-class>
    <group>P6</group>
  </record>

  <record>
    <sentence-number>12</sentence-number>
    <data-class>Good</data-class>
    <group>P6</group>
  </record>

  </document>
</results>
EOF

my $t= new XML::Twig(
   twig_handlers => {document => \&doc}
);
$t->parse($xfile);

sub doc {
    my ($twig, $doc) = @_;
    my $doc_csv = join ',', 
        $doc->att('datetime'),
        $doc->att('id'),
        $doc->att('sourcecategory'),
        $doc->att('schemeversion');
    print "$doc_csv\n" unless $doc->children('record');
    for my $rec ($doc->children('record')) {
        print join ',', $doc_csv,
            $rec->first_child('sentence-number')->text(),
            $rec->first_child('data-class'     )->text(),
            $rec->first_child('group'          )->text();
        print "\n";
    }
}

__END__
2006/01/25,\2006\200601\20060125\20060125_18.txt,News Archive,1.1
2006/01/25,\2006\200601\20060125\20060125_19.txt,News Archive,1.1,3,Target,P6
2006/01/25,\2006\200601\20060125\20060125_19.txt,News Archive,1.1,12,Good,P6