How can I use a database server from a Perl CGI script?

BEGIN {
  $ENV{ORACLE_HOME} = '/home/oracle/product/10.x.x';
  $ENV{TWO_TASK}    = 'DB';
}
$dbh = DBI->connect('dbi:Oracle:','scott', 'tiger');
#  - or -
$dbh = DBI->connect('dbi:Oracle:','scott/tiger');

my $db = DBI->connect("dbi:Oracle:host=$host;sid=$database", $user, $pass,
  { RaiseError => 0, PrintError => 0 } )
  or croak( "Unable to connect to DB - $DBI::errstr" );