in reply to Re: Best way to match a hash with large CSV file
in thread Best way to match a hash with large CSV file

Thanks a lot BrowserUk!!!

As you suggested I read the csv file line by line and did a search directly in the hash and completed the task in 6 seconds!

sub dataextractor($) { my $input = shift; my $output = shift; my $order = shift; my (@data); open(OUT,">".$output) or die "Can't open the file $output\n"; open(IN,"<".$input) or die "Can't open the file $input\n"; while (<IN>) { if ($. eq 1) { print OUT $_; next; } s/\r?\n$//; @data = split (',',$_); if ($data[1] eq $site_peakhr{$data[$order]}) { print OUT $_."\n"; } }#while close(IN); close(OUT); return($output); }