Using a hash approach 
use strict;

my %data=();
scan (0,'File1.txt');
scan (1,'File2.txt');
compare('log.txt');

# input
sub scan {
  my ($ix, $infile) = @_;
  open IN, '<', $infile or die "Could not open $infile : $!";
  my $count=0;
  while (<IN>){
    chomp;
    my ($key,$line) = split "\t",$_,2;
    $data{$key}[$ix] = $line;
    ++$count;
  }
  close IN;
  print "$count lines read from $infile\n";
}

# output
sub compare {
  my $logfile = shift;
  open LOG,'>',$logfile or die "Could not open $logfile : $!";
  my $count = 0;
  
  # compare lines of data using key
  for my $key (sort keys %data){
    if ($data{$key}[0] ne $data{$key}[1]){
      my @f1 = split "\t",$data{$key}[0];
      my @f2 = split "\t",$data{$key}[1];
      for my $c (1..@f1){
        if ($f1[$c-1] ne $f2[$c-1]){
          print LOG "Row $key Column $c File 1 Value- $f1[$c-1] File 2
+ Value- $f2[$c-1]\n";
          ++$count;
        }
      }      
    }
  }
  close LOG;
  print "$count lines written to $logfile\n";
}

[download]
poj

In reply to Re: Column by Column Comparison by poj
in thread Column by Column Comparison by documents9900

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