my @avgs = $dbh->selectrow_array($avgSQL); # CSV output method A print join(",", @cols) . "\n"; print join(",", @avgs) . "\n"; # CSV output method B (2-columns) print "Col,Avg\n"; printf("%s,%f\n", $cols[$_], $avgs[$_]) for 0 .. $#cols; #### my %avgsHash; @avgsHash{ @cols } = @avgs; # uses a hash slice to populate %avgsHash print "Col,Avg\n"; printf("%s,%f\n", $_, $avgsHash{$_}) for @cols;