Perl: Data from delimited file

#!/usr/bin/perl



		$temp = $ENV{'QUERY_STRING'};



  @pairs=split(/&/,$temp);
  foreach $item(@pairs)
   {
    ($key,$content)=split(/=/,$item,2);
    $content=~tr/+/ /;
    $content=~s/%(..)/pack("c",hex($1))/ge;
    $content=~s/\t/ /g;
    $fields{$key}=$content;
			}


$database = "database.txt";



if ($fields{'a'} =~ /^log$/){
print "Content-type: text/html\n\n";
open (DATA, "<$database") || print "No database file: $!";
flock (DATA, 2);
@lines = ;
flock (DATA, 8);
close (DATA);
foreach $line (@lines){
($ID,$URL,$name,$hits) = split(/\|\|/, $line);
print "$name..........................$hits
\n";
}
exit;
} elsif ($fields{'a'} !~ /[500-507]/){
print "Content-type: text/html\n\n";
print "Sorry, out of range, don't fiddle with the URL!

Access denied!";
exit;
}





open (DATA, "<$database") || print "No database file: $!";
flock (DATA, 2);
@lines = ;
flock (DATA, 8);
close (DATA);




foreach $line (@lines)
{
($ID,$URL,$name,$hits) = split(/\|\|/, $line);

	if ($fields{'a'} eq $ID) 
	{
	print "Location: $URL\n\n";
	}

}













open (DATAT, ">$database") || print "No database file: $!";
flock (DATAT, 2);



foreach $line (@lines)
{
($ID,$URL,$name,$hits) = split(/\|\|/, $line);



#if ($fields{'ID'} =~ /^$ID/)
if ($fields{'a'} =~ /$ID/) 
{
$hits++;
print DATAT ("$ID||$URL||$name||$hits\n");
}
else
{
#print DATAT $line . "\n";
print DATAT $line;
}


}

flock (DATAT, 8);
close (DATAT);


exit;