I wrote a script that checks fields (delimiter is a pipe) where if the last entry has the same last four field entries it will eliminate that last line with the duplicates. The script works but as usual I like to get it to look better and this site always provides a great way to critique and help me write a more efficient script. Please look at the script and advise how I can make it better.
Thanks!

Script: 
use strict;                  
my $db = 'C:\Inetpub\wwwroot\cgi-bin\test4.txt';
open(DATA, "$db") || die "Can not open: $!\n";
my @dat = (<DATA>);
close(DATA);
open(DATA, "$db") || die "NO GO: $!\n";
my @files;
foreach (@dat)
{
  my $key = join(" ", (split /\|/, $_)[1,2,3,4]);
  #print "$key\n";
  push(@files,$key);
}
#print "@files\n";

foreach (@files)
{
  chomp;
  $key{$_}++;
}

foreach (keys %key) 
{
    if($key{$_} > 1)
    {
          #print "$_ \n";
          my $db = 'test4.txt';
        open(DATA, "$db") || die "Can not open: $!\n";
        my @lines = (<DATA>);
        pop @lines;
         open(FOUT,"> test4.txt") or die $!;
        print FOUT @lines;
        close FOUT;
    }
}

close(DATA);

[download]
data in test4.txt:
34|4|45|56|45
45|34|45|00|23
45|34|45|00|27
34|4|456|56|03
36|4|456|56|03  #This line will be eliminated after the script is run 
+because last four fields are the same as the previous line.

[download]

In reply to Improvement on script needed. by Anonymous Monk

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