my $sort_dir = defined($params{sort_dir}) ? $params{sort_dir} * 1 : $sort_spec->{default}->[1];
my $sort_dir_str = $sort_dir ? 'ASC' : 'DESC';
- my $sort_by = $params{sort_by};
+ my $sort_by = $params{sort_by} || { };
$sort_by = $sort_spec->{default}->[0] unless $sort_spec->{columns}->{$sort_by};
my $nulls_str = '';
my $sort_by_str = $sort_spec->{columns}->{$sort_by};
$sort_by_str = [ $sort_by_str ] unless ref($sort_by_str) eq 'ARRAY';
- # generaate tiebreaker
+ # generate tiebreaker
push @$sort_by_str, @{ $sort_spec->{tiebreaker} };
$sort_by_str = join(', ', map { "${_} ${sort_dir_str}${nulls_str}" } @{ $sort_by_str });