open FH, '<', "$filename.csv" or die("Can't open $filename.csv");
$dbh->begin_work;
my $sth = $dbh->prepare("INSERT INTO T_$filename (".join(', ',@column).
   ") VALUES (".join(',',map{'?'} @column).")";

my $c_size = 500; #size of buffer chunk
my @buffer;

while (<FH>) {
   my @row = split(','); #No quoting issues in these files, yay!
   push @buffer, \@row;
   next unless (@buffer >= $c_size or eof(FH));
   
   while (@buffer) {
      my $row = shift @buffer;
      $sth->execute(@$row);
   }
}

close FH;
$dbh->commit;