for (my $i = 0; $i < @{$mydata}; $i++) {

  $account_number     = $mydata->[$i]{'account_number'} || '';
  ....

  if($email eq '') {
    bad_email("No email address found '$account_number'.");
    next;
  }
  ...
  if(($name eq '') || ($account_number eq '')) {
    $msg = "Missing information: Number = '$account_number', Name = '$name'.";
    next;
  }

  # Send  emails
  send_email( send my stuff here);
  ...

  exec_single_sql($sql, $db) || die "Unable to update table";
}