[Dbix-class] RecursiveUpdate and many to many

[Matt S Trout]

On Mon, Sep 29, 2008 at 05:39:25PM +0100, Pedro Melo wrote:
> Hi,
> 
> On Sep 29, 2008, at 4:50 PM, Matt S Trout wrote:
> 
> >On Sun, Sep 28, 2008 at 05:56:11PM +0100, Oliver Gorwits wrote:
> >>Ideally, DBIC would instead populate the relationship_info details
> >>after someone has set up __PACKAGE__->many_to_many(...). That would
> >>avoid this guesswork.
> >
> >That would make no sense at all since many-to-many is NOT A  
> >RELATIONSHIP.
> 
> I've been in this list for some years now that I've seen this phrase  
> written several times.
> 
> <pedantic>
> If I recall correctly my time at CS department where I was forced to  
> read the relational model (not the -for-dummies version that is SQL  
> today. but the true horrid version), many-to-many was in fact a  
> relationship.

In DBIx::Class terms, that's not how we model it.

> Having said that, it is trivial to use your own base class for your  
> sources in a way that you can catch many-to-many declarations and  
> cache the result somewhere private (your own version of  
> relationship_info()).

Please if you do that call it something -other- than relationship_info.
 
> I say that this is possible because I have code running in production  
> that does exactly that: creates a parallel relationship_info()

Much DBIC code and extension stuff assumes that anything in there is
a relationship in the DBIC sense.

if you start putting many-to-many stuff in there, your code is broken. It
just might not have caused you any bugs yet.

-- 
      Matt S Trout       Need help with your Catalyst or DBIx::Class project?
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