$dbh = DBI->connect("dbi:Informix:$database", $user, $pass, %attr);
$dbh = DBI->connect("DBI:Unify:dbname[;options]" [, user [, auth [, attr]]]);
$dbh = DBI->connect("dbi:Oracle:host=$host;sid=$sid", $user, $passwd);


##</code><code>##

$dbh = DBI->connect(Informix => $database,             $user, $pass, %attr);
$dbh = DBI->connect(Unify    => "dbname[;options]",    $user, $pass, %attr);
$dbh = DBI->connect(Oracle   => "host=$host;sid=$sid", $user, $pass, %attr);
...