[Dbix-class] table-per-subclass - how it works?

[Alex Erzin]

Hm... it really works, but where are benefits of OOP? ;)
There is no inheritance at all, and to access parent's properties I should call parent directly, so inheritance just replaced with incapsulation, and it's no one what i try to find.

Some years ago we have implemented inheritance in ORM in some commercial project in Perl, later I have swithed to java and have found Hibernate it really cool with ORM.
But now I have returned to Perl and I think that DBIx::Class can help me with ORM, but right now i'm confused that cannot find "standard" solution for typical task.


15.06.2012, 10:25, "Hailin Hu" <i at h2l.name>:
> Is it acceptable like something below
>
> package Target;
> ...
> package Host;
> ...
> __PACKAGE__->belong_to('target' => 'Target', 'target_id');
> sub column_only_exists_in_target {
>   my $self = shift;
>   return $self->target->column_only_exists_in_target;
> }
>
> well, it is not a good solution, but it could work, I think :)
>
> On Fri, Jun 15, 2012 at 3:04 PM, Alex Erzin <eaa-home at yandex.ru> wrote:
>
>>  Hello,
>>
>>  I need to implement table-per-class inheritance, as it simple made in Hibernate in Java (more details can be found here http://docs.jboss.org/hibernate/orm/4.1/manual/en-US/html/ch10.html#inheritance-tablepersubclass),
>>  but cannot find right way how to do it in DBIx::Class.
>>
>>  For example, I have two objects: Target (with properties ID, Description) and Host (ID, Hostname, IP), Host inherited from Target, and on table-level there are two tables Host and Target, joined by ID field.
>>
>>  CREATE  TABLE  `mydb`.`target` (
>>   `target_id` INT NOT NULL ,
>>   `description` VARCHAR(45) NULL ,
>>   PRIMARY KEY (`target_id`) )
>>
>>  CREATE  TABLE `mydb`.`host` (
>>   `target_id` INT NOT NULL ,
>>   `hostname` VARCHAR(45) NULL ,
>>   `ip` VARCHAR(45) NULL ,
>>   PRIMARY KEY (`target_id`) ,
>>   CONSTRAINT `fk_host_target`
>>     FOREIGN KEY (`target_id` )
>>     REFERENCES `mydb`.`target` (`target_id` )
>>  )
>>
>>  How to implemeng there classes Target and Host, so it possible to write
>>
>>  print $target->id(), $targer->description()
>>  print $host->id(), $host->description(), $host->hostname(), $host->ip()
>>
>>  ?
>>
>>  I have no ideas how to implement inheritance, and all my experiments are failed - from Host i cannot get access to parent properties like description.
>>  Could you help me please (with examples)?
>>
>>  Thanks.
>>
>>  --
>>  eaa@
>>
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>
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-- 
eaa@