$rc = $sth->bind_col($col_num, \$col_variable);
  $rc = $sth->bind_columns(@list_of_refs_to_vars_to_bind);

##</code><code>##

  $rc = $sth->bind_col($col_num, $col_variable);
  $rc = $sth->bind_columns(@list_to_bind);

##</code><code>##

my ($col_num)=@_;
my $col_variable=\$_[1];

##</code><code>##

my @refs=map { \$_ } @_;