my $array_ref = $select->fetchall_arrayref();

##</code><code>##

..$select->fetchrow_array

##</code><code>##

my $array_ref = $select->fetchall_arrayref([0]);

##</code><code>##

# instead of 
my $array_ref = $select->fetchall_arrayref();
# try
my $array_ref = $select->fetchall_arrayref;

##</code><code>##

fetchall_arrayref
  $tbl_ary_ref = $sth->fetchall_arrayref;
  $tbl_ary_ref = $sth->fetchall_arrayref( $slice );
  $tbl_ary_ref = $sth->fetchall_arrayref( $slice, $max_rows  );