use CGI;
use strict;

my $query = CGI->new();
          # set up my defaults
my %parameters = (name => ["Anonymous"],
                  address => ["No fixed abode"],
                  phone => ["Not Available"]);

          # pull everything out of param and put in
          # my hash.
foreach my $key ($query->param())
{
        $parameters{$key} = [$query->param($key)];
}

##</code><code>##

foreach my $key (keys %defaults)

##</code><code>##

          # then to do your substitution:
$SQLStatement =~ s/\$(\w+)/$parameters{$1}[0]/eg;

##</code><code>##

foreach my $key (keys %defaults)
{
     foreach my $value (@$key)
     {
          $SQLStatement =~ s/\$(\w+)/$value/eg;
               # then use your $SQLStatement ....
     }
}