Shell Programming and Scripting

#! /opt/third-party/bin/perl

my $first = 1;
open(FILE, "<", "filename");

while(<FILE>) {
  chomp;
  s/ //g;
  my @arr = split(/\|/);
  $first == 1 || exists $firstHash{$arr[0]} ? pushValues(\%firstHash, \@arr, \$first) : pushValues(\%secondHash, \@arr, \$first);
}

close(FILE);

foreach my $k ( keys %firstHash ) {
  print "first set:$k\n";
}

foreach my $k ( keys %secondHash ) {
  print "second set:$k\n";
}

sub pushValues {
  my ($hash, $arr, $first) = @_;

  $$first = 0;
  foreach (@$arr) {
    $hash->{$_} = 1;
  }
}

exit 0

Parent -> A
Children -> B E F G

Parent -> B
Children-> C D

SELECT ip2 AS Parent, GROUP_CONCAT(ip1 SEPARATOR ', ') AS Children FROM br GROUP BY ip2 LIMIT 15;