my %default_bind = ( age => 23, height => 75, birthday => undef );
my @key_order = qw( age height birthday );

sub {
    my $caller=shift;

    my @bind = @{ { %default_bind, @_ } }{ @key_order };

    $rf->execute(@bind) or
        $caller->complain("Error executing this and that.");

    $rf->fetchall_arrayref;
}