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DBIx::Class::IntrospectableM2M(3pm) User Contributed Perl Documentation DBIx::Class::IntrospectableM2M(3pm)


DBIx::Class::IntrospectableM2M - Introspect many-to-many shortcuts


In your DBIx::Class Result class (sometimes erroneously referred to as the 'table' class):

  __PACKAGE__->load_components(qw/IntrospectableM2M ... Core/);
  #Digest encoder with hex format and SHA-1 algorithm
  __PACKAGE__->many_to_many(roles => user_roles => 'role);

When you want to introspect this data

   my $metadata = $result_class->_m2m_metadata->{roles};
   #  $metadata->{accessor} method name e.g. 'roles'
   #  $metadata->{relation} maping relation e.g. 'user_roles'
   #  $metadata->{foreign_relation} far-side relation e.g. 'role
   #  $metadata->{attrs}  relationship attributes, if any
   # Convenience methods created by DBIx::Class
   #  $metadata->{rs_method}     'roles_rs'
   #  $metadata->{add_method}    'add_to_roles',
   #  $metadata->{set_method}    'set_roles',
   #  $metadata->{remove_method} 'remove_from_roles'

Note: The component needs to be loaded before Core.


This module is fairly esoteric and, unless you are dynamically creating something out of a DBIC Schema, is probably the wrong solution for whatever it is you are trying to do. Please be advised that compatibility is not guaranteed for DBIx::Class 0.09000+. We will try to manitain all compatibility, but internal changes might make it impossible.


Because the many-to-many relationships are not real relationships, they can not be introspected with DBIx::Class. Many-to-many relationships are actually just a collection of convenience methods installed to bridge two relationships. This DBIx::Class component can be used to store all relevant information about these non-relationships so they can later be introspected and examined.



Extended to store all relevant information in the "_m2m_metadata" HASH ref.


Accessor to a HASH ref where the keys are the names of m2m relationships and the value is a HASH ref as described in the SYNOPSIS.


Guillermo Roditi (groditi) <>


Copyright (C) 2008 by Guillermo Roditi

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

2022-06-13 perl v5.34.0