我正在关注DBIx::Class::Migration的教程,并转到step,其中DBIx::Class::ResultSet的具有属性使用了两种不同的语法interchangeably(crtl + f ResultSet :: Artist,因为它离链接部分较远)。第一个/注释掉的一个不起作用(返回零行),但是在我编写时记录了下来,第二个做了(注释了一行)。
我正在忽略某些东西还是这是一个错误?
package MusicBase::Schema::ResultSet::Artist;
use strict;
use warnings;
use base 'DBIx::Class::ResultSet';
sub has_more_than_one_cds {
my $me = (my $self = shift)->current_source_alias;
my $rs = $self->search(
undef,
{
join => [ 'cd_rs' ],
'+select'=> [ { count => 'cd_rs.cd_id', -as => 'cd_count' } ],
'+as'=> [ 'cd_count' ],
group_by => [ "$me.artist_id" ],
# having => { cd_count => { '>', 1 } } # This does not work
having => { cd_count => \'> 1' } # This does despite being
# undocumented
}
);
return $rs
}
1