> my $sql = "SELECT * INTO OUTFILE 'g:/dbf2csv/$filename'
> FIELDS TERMINATED BY ','
> LINES TERMINATED BY '\r\n' FROM reg501";

That syntax is specific to MySQL and won't work with DBD::CSV. You can accomplish the same thing like this:

$dbh->{csv_files}->{outfile} = {
    file     => "g:/dbf2csv/$filename",
    sep_char => ',',
    eol      => '\r\n'
};
$dbh->do("
    CREATE TABLE outfile AS SELECT * FROM sourceTable
");
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