[Dbix-class] select * from questions

[Gavin Carr]

On Thu, Apr 27, 2006 at 07:25:37AM -0800, Aran Deltac wrote:
> On 4/27/2006, "Gavin Carr" <gavin at openfusion.com.au> wrote:
> >Just starting to use DBIx::Class in anger for the first time and have
> >a few questions/comments:
> >
> >1. Is there a way of accessing the $schema object from a Row or ResultSet
> >method, or is that a Bad Thing to do? For instance, say per the cookbook
> 
> No, its not a bad thing.  Here's what you do:
> 
> $obj->result_source->schema();

Ah, luverly.

> I just yesterday submitted a fix to the ResultSource docs to show that
> schema is available through it.  This may be why you didn't know you
> could do that.  :)

That may have had something to do with it. ;-)

> If there is a relationship, then you can just call the methods that your
> relationship created to get at the related objects.

Except that this was in new() before I had an object. Your $schema would have 
worked fine though.

> >i.e. related_resultset was just a resultset constructor using a
> >relationship name instead of a table name. Clearly that's wrong, and a
> >'related' resultset involves a join from the original table. This probably
> >needs to be spelled out more clearly in the docs for both related_resultset
> >and search_related. I'm not clear enough about the semantics to have a stab
> >at it myself, but at least the fact that it's a joined resultset should
> >probably be made explicit.
> 
> I've not looked at the docs, but to me the method name
> related_resuletset implies a join.  But, more verbose docs are rarely a
> bad thing.  If you can come up with some extra text that makes this a
> bit more explicit I'd be happy to toss it in to the docs.

Okay, how about just:

  related_resultset 

  Arguments: $relationship_name
  Return Value: $resultset

  Returns a related (i.e. joined) resultset for the supplied relationship name. 

Or more verbosely:

  Returns a related resultset for the supplied relationship name. A related
  resultset involves a join between the resultsets using the relationship
  condition. 

> >3. For situations where you have queries that aren't supported by DBIC yet,
> >is there a way to source the underlying Schema dbh for doing statement
> >handles directly, or this not kosher? There's nothing obvious in
> >DBIx::Class::Schema or DBIx::Class::Storage::DBI.
> 
> Thats not kosher, since DBIC _should_ handle all situations (although
> there are admitedly a few things it can't do, for now).  So, in those
> rare cases, you can get at it with you storage object.  Such as
> $obj->result_source->storage->dbh();

Great, thanks. Maybe that method should be documented in 
DBIx::Class::Storage::DBI (laced with suitable and dire warnings)?

> >4. Is there an equivalent idiom for overriding ResultSet methods as
> >there is for Row methods in (1) above? I tried something like this:
> >
> >__PACKAGE__->load_components(qw/ ResultSetManager Core /);
> >
> >  sub search : ResultSet {
> >      my ($self) = shift;
> >      my ($cond, $attrs) = @_;
> >
> >      $attrs->{order_by} ||= 'name DESC';
> >
> >      $self->next::method($cond, $attrs);
> >  }
> >
> >but that generates a Class::C3 error:
> >
> >  No next::method 'search_like' found for 44285 at /usr/lib/perl5/site_perl/5.8.8/Class/C3.pm line 192
> 
> I can't remember, but I know somewhere in the docs there is a section
> that discusses writing your own result sets.

The Cookbook discusses adding new ResultSet methods, but not overriding
them, which is where I got entangled.

Thanks a lot for your answers Aran.

Cheers,
Gavin