#--------------------------------------------------------
# define "Person" objects
package Person;

use base qw(Class::Tangram);
$schema = {
    table => "names",
    fields => {
        string => [ qw(first last) ]
    }
};

#--------------------------------------------------------
# define which objects we have in our database
package Project;
use Tangram::Relational;
$dbschema = Tangram::Relational->schema
     ({ classes => [ 'Person' => $Person::schema ]});

sub schema { $dbschema };

#--------------------------------------------------------
#  the main program
package main;

# connect to the database.
my $storage = Tangram::Relational->connect(Project->schema,
                                           $dsn, $u, $p);

# insert a new Person
$storage->insert(Person->new( first => "Harry",
                              last => "Potter" ));

# $remote_person refers to a person in the database,
# for select queries.
my $remote_person = $storage->remote("Person");

if ($storage->select
       ( $remote_person,
         $remote_person->{first} eq "Harry" )) {
   print "Potter is IN THE HOUSE.\n";
}

# iterate through all rows
for my $person ($storage->select("Person")) {
    print $person->last.": ".$person->first."\n";
}

# delete every row matching "Potter"
$storage->erase
    ($storage->select
        ( $remote_person,
          $remote_person->{last} eq "Potter" ));
 
if ($storage->select
       ( $remote_person,
         $remote_person->{last} eq "Potter" )) {
   die "Can't get rid of that damn Harry Potter!";
}