#!/usr/bin/perl
use strict;
use warnings;
use Text::CSV_XS;
use DBI;
my $csv_inputfile = "use_me.txt"; # change me
my %data; # hash for storing csv data
my $csv = Text::CSV_XS->new;
open my $fh, '<', $csv_inputfile or die "can't open $csv_inputfile: $! \n";
while (my $line = <$fh>) {
  $line =~ s/^\s+//;  # strip leading whitespace
  next unless $line;  # ignore blank lines
  if ( $csv->parse($line) ) {
    my ($nbname,$ip) = $csv->fields();
    next unless $nbname;
    $data{$nbname} = {
        IP => $ip        || '',
      NBNAME  => $nbname || '',
    };
  } else {
    my $error = $csv->error_diag();
    print "Parse error: line $. : $error.\n";
  }
}
close $fh;
my $user = undef;
my $pass = undef;
my $dbh = DBI->connect("DBI:mysql:pstsize;host=localhost",$user,$pass, {RaiseError => 1, AutoCommit => 1},);
unless ($dbh) {
  die "Could not get database handle.";
}
my $sth = $dbh->prepare( select_data() );
eval {
  $sth->execute();
};
if ($@) {
  die "Database error: ", $dbh->errstr;
}
while ( my ($nbname, $ip) = $sth->fetchrow ) {
unless ($ip) {
    if ($data{$nbname}{'IP'}) {
      print ".. but CSV file has value: $data{$nbname}{'IP'}{'NBNAME'}.";
    }
    print "\n";
  }
}
$sth->finish;
$dbh->disconnect;
sub select_data {
  return <<"  END_SQL";
    SELECT DISTINCT
      nbname,
      ipaddr
    FROM
      sizehist
  END_SQL
}