so my thought was to use an array to store the keys, then verify if that key exists in part or whole, then replace the part with the longest string. that solves the problem of taking arbitrary substr so "group tw" will not replace "group twelve" and "group two"...
It's a good thought, I think, but there is a flaw in my logic, the loop just keeps repeating and growing. (I'm dealing with about 5k lines, I've seen $i hit over 20,000...)
Here's what I cooked up: 
#!/usr/bin/perl
use strict;
use warnings;

my %seen;
my @gp_name = "INITIALIZING";


open my $FHIN, '<', $ARGV[0] or die $!;
open my $FHNEW, '>', "$ARGV[0].newest2.csv" or die $!;
open my $FHDEL, '>', "$ARGV[0].deleted2.csv" or die $!;

LABEL:
foreach my $line (<$FHIN>){
  $line =~ s/["]//msx;
  my ($key, $rest) = split/,/, $line, 2;
  $key =~ s/ [-&_+'] / /msx;
  $key =~ s/ ( [a-z] ) ( [A-Z] )/$1 $2/msx;
    
  for (my $i = 0; $i < @gp_name; $i++) {
    print "enter my \$i = $i\n ";
    if ($key =~ $gp_name[$i]){
      if (($gp_name[$i] cmp $key) > 0 
         || ($gp_name[$i] cmp $key) == 0) {
             next LABEL;
      } elsif (($gp_name[$i] cmp $key) < 0) {
         $gp_name[$i] = $key;
      }
    } else {
      push @gp_name, $key;
    }
  }#end for    
    
  ($seen{$key}++) ? 
     print $FHDEL "DUP, $line"  : 
     print $FHNEW "$key,$rest";
}# end foreach

close $FHNEW, $FHDEL;

[download]

In reply to Re^3: Remove duplicate entries by PyrexKidd
in thread Remove duplicate entries by PyrexKidd

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