[Dbix-class] Re: has_many/belongs_to relationship to non-primary key

[Matija Grabnar]

Matija Grabnar wrote:
> Is this something that database theory makes impossible (and I just 
> didn't know it) or is this a bug in DBIx::Class?
>
> Summary: Say I have two Classes, in a belongs_to / has_many 
> relationship, but with one important difference: the belongs_to 
> relationship does not go to the  primary key of the other table, but 
> to another key. When I try to do that, I get an extra constraint that 
> prevents me from inserting anything into the table.
>
Commenting to my own message, but I looked at the source of 
SQL::Translator::Parser::DBIx::Class.pm,  and that decision is made 
explicitly: the code checks if the target of the relationship is the 
whole of the primary keys, and if not, it adds an addition foreign key 
constraint.

Again, this constraint gets in my way pretty badly, and I think it is 
somewhat too strict. As I understand it, there is no need for the target 
of the belongs_to relationship to be the primary key, all that you need 
to ensure is that it be a UNIQUE key.

I'm rewriting the if statement that does this, and what I've written so 
far seems to pass the tests defined in 86sqlt.t, so I don't think I'm 
getting rid of any foreign key constraints that _should_ be there.

I hope I'll be able to submit a full patch very soon.

Best regards,
                Matija Grabnar