Again, this is all guesswork based on reading the documentation.

my $sth = $dbh->query("select a, b from c where d=1");

while (my @row = $sth->fetchrow) {
  push @data, \@row;
}
[download]

Will I have a column, and not a row?

You'll have a 2-dimensional array of rows and columns (or, more accurately, an array of rows where each element contains a reference to an array containing all of the columns from one record in the database).