CODEWITHSUNDEEP
mysqlperlcatalyst
p1234
p1234

Reputation: 529

Perl / DBIx::Class::Schema::Loader suffixes _2 to duplicate relationship name

I'm pretty new to Perl and got this Catalyst project to maintain. There is a MySQL database, that is connected via DBIx and I need to do some changes. In the documentation of the project I found, how the model is created:

dev:~# script/prj_create.pl 
model PrjDB DBIC::Schema 
prj::Schema::PrjDB 
create=static 
preserve_case=1 
moniker_map='sub {return $_[0];}' 
col_accessor_map='sub {return $_[0];}' 
inflect_plural='sub {return $_[0];}' 
inflect_singular='sub {return $_[0];}' 
exclude='^view_' 
components=TimeStamp,PassphraseColumn,DynamicDefault 
use_moose=1 
dbi:mysql:prj root ********

In the database there are relationships like

company_user belongs_to company (foreign key)
company_user has_many company_user ("last_changed_by_user")
company_user has_many company (secondary relationship via "last_changed_by_user")

The original model that I got has following lines created in "company_user.pm":

__PACKAGE__->has_many(
  "company",
  "prj::Schema::PrjDB::Result::company",
  { "foreign.last_changed_by" => "self.id" },
  { cascade_copy => 0, cascade_delete => 0 },
);

__PACKAGE__->belongs_to(
  "company",
  "prj::Schema::PrjDB::Result::company",
  { id => "company" },
  { is_deferrable => 1, on_delete => "CASCADE", on_update => "CASCADE" },
);

If I now try to recreate the model I get: 

__PACKAGE__->has_many(
  "company",
  "prj::Schema::PrjDB::Result::company",
  { "foreign.last_changed_by" => "self.id" },
  { cascade_copy => 0, cascade_delete => 0 },
);

__PACKAGE__->belongs_to(
  "company_2",
  "prj::Schema::PrjDB::Result::company",
  { id => "company" },
  { is_deferrable => 1, on_delete => "CASCADE", on_update => "CASCADE" },
);

(Notice the "_2" suffix in the belongs_to package.)

With this model, all the existing code breaks as it can't find some methods anymore. I frankly don't really know, what to search for, so I hoped someone here can help me.

Is there any option in loader, that I need to set / unset or is it maybe something that doesn't even has to do anything with the loader?

Edit: The only thing I found for a {rel}_2 notation so far is in the ResultSet class where it says:

If the same join is supplied twice, it will be aliased to {rel}_2 (and similarly for a third time).

I don't know, if this is the source of my problem and how to circumvent it.

One thing, that i didn't had in my original question: the working model was created with a DBIx version of 2012(? I think, not documented) and I now use the newest available one.

Upvotes: 1

Views: 207

Answers (2)

p1234
p1234

Reputation: 529

I fixed the naming problem by remapping the wrong names in the generator script call via rel_name_map. There are just two problematic joins, so the effort is sufficient for me. I know that this is no general solution, but maybe it helps someone.

I used rel_name_map like so:

dev:~# script/prj_create.pl 
       model PrjDB DBIC::Schema 
       prj::Schema::PrjDB 
       create=static 
       preserve_case=1 
       moniker_map='sub {return $_[0];}' 
       rel_name_map="{company_2 => \"company\", user_2 => \"user\"}"
       col_accessor_map='sub {return $_[0];}' 
       inflect_plural='sub {return $_[0];}' 
       inflect_singular='sub {return $_[0];}' 
       exclude='^view_' 
       components=TimeStamp,PassphraseColumn,DynamicDefault 
       use_moose=1 
       dbi:mysql:prj root ********

Upvotes: 0

Len Jaffe
Len Jaffe

Reputation: 3484

I'm going to suggest that the second line in this is your problem:

company_user belongs_to company (foreign key) 
company_user has_many company_user ("last_changed_by_user") 
company_user has_many company (secondary relationship via "last_changed_by_user")

Your user table has a foereign key relatioship to itself, so since its has_many realtionship with itself is called company, the belongs_to realtionship is named company_2.

My guess is that the previous version did something similar, but the programmer edited the generated files to change company_2 to something other name.

I will guess that the broken code is complaining of a missing relationship. That will be the name you need to use.

But why are you regenerating the DBIC stuff instead of juts editing it? Didn't it get committed to source control?

Upvotes: 1

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