Hashes are great for grouping. 

my %users_by_account;

...

push @{ $users_by_account{$account_name} }, $username;

...

for my $account_name (sort keys %users_by_account) {
   my $users = $users_by_account{$account_name};

   print("Account $account_name\n");

   for my $username (@$users) {
      print("$username\n");
   }

   print("\n");
}

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In reply to Re: Unique Array from DB by ikegami
in thread Unique Array from DB by Anonymous Monk

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