I think you've got your '@' and '$' in the wrong places. join() returns a SCALAR, split() returns a LIST (or a scalar, but I think you want the list here). 
my @column_names = qw( chk );  # I assume you have more?
my $columns_joined =
  join "," =>
  map { $db->quote($fd{$_}) }
  grep { exists $fd{$_} }
  @column_names;
my @column_values = split /\0/, $columns_joined;

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Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: Splitting \0 by japhy
in thread Splitting \0 by Quicksilver

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