Hi all, thanks for your suggestions. My solution is appended below. Passing the hidden field $input solved my problem...
Regards,
Stacy. 
use CGI qw(:standard :netscape *table);
use CGI::Carp qw(fatalsToBrowser);
use CGI::Pretty qw( :html3 );
use strict;

my ($order_by,$sql,$order_by_check,$order_by_input);

$sql = qq{SELECT * FROM TABLE}; 

$order_by       = param('order_by');
$order_by_check = param('order_by_check');

if ($order_by) {
  $sql .= " ORDER BY $order_by ";
  if ($order_by_check eq $order_by) {
    $sql .= ' DESC ';
    $order_by_check = $order_by;
  } else {
    $sql .= ' ASC ';
    $order_by_input = "<INPUT TYPE=hidden NAME=order_by_check VALUE=\"
+$order_by\">";
  }
}

print header,
  
  start_html(),
  start_form(),
  
  center(
     start_table(),
     Tr(td(submit('order_by','FAULT_NO',)),
        td(submit('order_by','ISSUE')),
        td(submit('order_by','RESPONSE'))),
     end_table(),
     p($sql),
     $order_by_input,
    ),
  
  end_form(),
  end_html();

exit;

[download]

In reply to Re: Re: Using CGI params for SQL statement by maderman
in thread Using CGI params for SQL statement by maderman

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