MyDB::Schema::Actor->many_to_many('roles' => 'actorroles', 'role');
## Using relationships
- $schema->resultset('Actor')->roles();
- $schema->resultset('Role')->search_related('actors', { Name => 'Fred' });
- $schema->resultset('ActorRole')->add_to_roles({ Name => 'Sherlock Holmes'});
+ $schema->resultset('Actor')->find({ id => 1})->roles();
+ $schema->resultset('Role')->find({ id => 1 })->actorroles->search_related('actor', { Name => 'Fred' });
+ $schema->resultset('Actor')->add_to_roles({ Name => 'Sherlock Holmes'});
See L<DBIx::Class::Manual::Cookbook> for more.
=back
-Creates a one-to-many relationship, where the corresponding elements of the
-foreign class store the calling class's primary key in one (or more) of its
-columns. This relationship defaults to using C<$accessor_name> as the foreign
-key in C<$related_class> to resolve the join, unless C<$foreign_key_column>
-specifies the foreign key column in C<$related_class> or C<cond> specifies a
-reference to a join condition hash.
+Creates a one-to-many relationship, where the corresponding elements
+of the foreign class store the calling class's primary key in one (or
+more) of its columns. This relationship defaults to using the end of
+this classes namespace as the foreign key in C<$related_class> to
+resolve the join, unless C<$foreign_key_column> specifies the foreign
+key column in C<$related_class> or C<cond> specifies a reference to a
+join condition hash.
=over
My::Schema::Item->has_many('rels', 'My::Schema::Relationships',
[ { 'foreign.LItemID' => 'self.ID' },
{ 'foreign.RItemID' => 'self.ID'} ]);
+
=back
# in an Author class (where Author has_many Books)
+ # assuming related class is storing our PK in "author_id"
My::DBIC::Schema::Author->has_many(
books =>
'My::DBIC::Schema::Book',
'author_id'
);
- # OR (same result, assuming related_class is storing our PK)
+ # OR (same result)
My::DBIC::Schema::Author->has_many(
books =>
'My::DBIC::Schema::Book',
+ { 'foreign.author_id' => 'self.id' },
);
-
- # OR (same result)
+
+ # OR (similar result, assuming related_class is storing our PK, in "author")
+ # (the "author" is guessed at from "Author" in the class namespace)
My::DBIC::Schema::Author->has_many(
books =>
'My::DBIC::Schema::Book',
- { 'foreign.author_id' => 'self.id' },
);
-
+
# Usage
# resultset of Books belonging to author
If you delete an object in a class with a C<has_many> relationship, all
the related objects will be deleted as well. To turn this behaviour off,
-pass C<< cascade_delete => 0 >> in the C<attr> hashref. However, any
-database-level cascade or restrict will take precedence over a
-DBIx-Class-based cascading delete.
+pass C<< cascade_delete => 0 >> in the C<$attr> hashref.
+
+The cascaded operations are performed after the requested delete or
+update, so if your database has a constraint on the relationship, it
+will have deleted/updated the related records or raised an exception
+before DBIx::Class gets to perform the cascaded operation.
If you copy an object in a class with a C<has_many> relationship, all
the related objects will be copied as well. To turn this behaviour off,
=item cond
A hashref where the keys are C<foreign.$column_on_related_table> and
-the values are C<self.$foreign_key_column>. This is useful for
+the values are C<self.$matching_column>. This is useful for
relations that are across multiple columns.
=back
If you update or delete an object in a class with a C<might_have>
relationship, the related object will be updated or deleted as well. To
turn off this behavior, add C<< cascade_delete => 0 >> to the C<$attr>
-hashref. Any database-level update or delete constraints will override
-this behavior.
+hashref.
+
+The cascaded operations are performed after the requested delete or
+update, so if your database has a constraint on the relationship, it
+will have deleted/updated the related records or raised an exception
+before DBIx::Class gets to perform the cascaded operation.
See L<DBIx::Class::Relationship::Base> for documentation on relationship
methods and valid relationship attributes.
=item cond
A hashref where the keys are C<foreign.$column_on_related_table> and
-the values are C<self.$foreign_key_column>. This is useful for
+the values are C<self.$matching_column>. This is useful for
relations that are across multiple columns.
=back