my @key = grep defined, $key, $key2, $key3;

my %tableData;

my $store_row = eval join("", q(
sub {
	my $row = shift;
	$tableData), map("{delete \$row->{'$_'}}", @key), q( = $row;
}));
	
while (my @data = $dbh -> dbnextrow) {
	s/^\s|\s$//g for @data;

	my %tblData;
	@tblData{@columnnames} = @data;

	$store_row(\%tblData);
}