[SP-pm] DBIx::Class - problema com colunas

[Daniel de Oliveira Mantovani]

Olha o que eu encontrei no manual,

<manual>
   Whole related objects
       To fetch entire related objects, e.g. CDs and all Track data,
use the 'prefetch' attribute:

         $schema->resultset('CD')->search(
           { 'Title' => 'Funky CD',
           },
           { prefetch      => 'tracks',
             order_by  => ['tracks.id'],
           }
         );

       This will produce SQL similar to the following:

         SELECT cd.ID, cd.Title, cd.Year, tracks.id, tracks.Name,
tracks.Artist FROM CD JOIN Tracks ON CD.ID = tracks.CDID WHERE
cd.Title = 'Funky CD' ORDER BY 'tracks.id';

       The syntax of 'prefetch' is the same as 'join' and implies the
joining, so there is no need to use both together.



         while(my $row = $search_rs->next) {
            print $row->tracks->name; ## WORKS
         }
</manual>



No seu vai ficar algo assim,

         my @roll = $schema->resultset('spider_info')->search( {
prefetch      => 'threads', })->all;

         say $_->threads->thread_id

(Se o seu relacionamento estiver certo, será algo do gênero)

perldoc DBIx::Class::Manual::Joining

Até mais André!

[]'s


2010/6/17 Andre Carneiro <andregarciacarneiro em gmail.com>:
> Salve monges.
>
> Tenho no meu esquema duas classes que representam as tabelas, conforme
> abaixo:
> <tabela 1>
> package Scap2::DBIC::Schema::Spider_Info;
> use strict;
> use warnings;
> use base 'DBIx::Class';
> __PACKAGE__->load_components("Core");
> __PACKAGE__->table("spider_info");
> __PACKAGE__->add_columns(
>   "spider_id",
>   { data_type => "INTEGER", is_nullable => 0, size => undef },
>   "spider_name",
>   { data_type => "VARCHAR", is_nullable => 0, size => undef },
>   "curr_process",
>   { data_type => "INTEGER", is_nullable => 0, size => undef },
>   "start_time",
>   { data_type => "DATE", is_nullable => 0, size => undef },
>   "end_time",
>   { data_type => "DATE", is_nullable => 0, size => undef },
>   "total_time",
>   { data_type => "DATE", is_nullable => 0, size => undef },
>   "parser_time",
>   { data_type => "DATE", is_nullable => 0, size => undef },
>   "amount",
>   { data_type => "INTEGER", is_nullable => 0, size => undef },
>   "amount_real",
>   { data_type => "INTEGER", is_nullable => 0, size => undef },
>   "status",
>   { data_type => "INTEGER", is_nullable => 0, size => undef },
>   "executed",
>   { data_type => "INTEGER", is_nullable => 0, size => undef },
> );
> __PACKAGE__->set_primary_key("spider_name");
> #__PACKAGE__->has_many(name => "Scap2::DBIC::Schema::Job");
> __PACKAGE__->has_many(threads =>
> 'Scap2::DBIC::Schema::ThreadList','spider_name');
>
> </tabela 1>
>
> <tabela 2>
> package Scap2::DBIC::Schema::ThreadList;
> use strict;
> use warnings;
> use base 'DBIx::Class';
> __PACKAGE__->load_components("Core");
> __PACKAGE__->table("thread_list");
> __PACKAGE__->add_columns(
>   "thread_id",
>   { data_type => "integer", default_value => undef, is_nullable => 0, size
> => 20 },
>   "spider_name",
>   { data_type => "text", default_value => undef, is_nullable => 0, size =>
> 100 },
>   "ospid",
>   { data_type => "integer", default_value => undef, is_nullable => 0, size
> => 20 },
>  "syspid",
>   { data_type => "integer", default_value => undef, is_nullable => 0, size
> => 20 },
>
> );
> __PACKAGE__->set_primary_key('ospid');
> #__PACKAGE__->belongs_to(spider_info
> =>'Scap2::DBIC::Schema::Spider_Info','spider_name');
> __PACKAGE__->belongs_to(spider_info =>'Scap2::DBIC::Schema::Spider_Info' =>
>  {'foreign.spider_name' => 'self.spider_name' } );
>
> </tabela2>
>
>
>
> Esses relacionamentos estão ok(não tá gerando erro pelo menos, e quando eu
> uso DBI_TRACE o join está correto!)
>
> A minha pesquisa utilizando essa relação, se resume no seguinte trecho de
> código:
>
> <pesquisa>
> sub load_all {
> my ( $self ) = @_;
> my @resultset = undef;
> # eval{@resultset =
> $self->schema->resultset('ThreadList')->related_resultset('spider_info')->all
> };
> # eval{@resultset =
> $self->schema->resultset('ThreadList')->search_related('spider_info',{});
> eval{@resultset = $self->schema->resultset('Spider_Info')->search({},{join
> => 'threads'});
> };
> if($@){
> print "\n\nOOOPS! Nao consegui montar a lista de threads --- $@\n\n"
> }else {
> my @list = ();
> $self->thread_list(\@resultset);
> }
>         print Dumper $self->thread_list;
> return $self->thread_list;
> }
> </pesquisa>
>
> Minha pergunta é: Por que o DBIx::Class não inclui as colunas das duas
> tabelas envolvidas no relacionamento?
> SQL gerada pelo DBI_TRACE:
> SELECT me.spider_id, me.spider_name, me.curr_process, me.start_time,
> me.end_time, me.total_time, me.parser_time, me.amount, me.amount_real,
> me.status, me.executed FROM spider_info me LEFT JOIN thread_list threads ON
> threads.spider_name = me.spider_name
>
>
> Thx!
>
>
> --
> André Garcia Carneiro
> Analista/Desenvolvedor Perl
> (11)82907780
>
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>



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