NAME

Class::DBI::Relationship::HasManyOrdered - A Class::DBI module for Ordered 'Has Many' relationships

SYNOPSIS

In your classes:

 package ContentManager::DBI;
 use base 'Class::DBI';

 ContentManager::DBI->connection('dbi:mysql:dbname', 'username', 'password');
 __PACKAGE__->add_relationship_type(has_many_ordered => 'Class::DBI::Relationship::IsA');

 ...

 package ContentManager::Image;
 use base 'ContentManager::DBI';

 ContentManager::Image->table('images');
 ContentManager::Image->columns(All => qw/image_id name position filename/);

 ...

 package ContentManager::Page;
 use base 'ContentManager::DBI';

 ContentManager::Page->table('pages');
 ContentManager::Page->columns(All => qw/page_id title date_to_publish date_to_archive/);
 Page->has_a(category => Category);
 Page->has_many(authors => Authors);
 Page->has_many_ordered(paragraphs => Paragraphs => {sort => 'position', map => 'PageParagraphs'});
 Page->has_many_ordered(images => Images => {sort => 'position', map => 'PageImages'});

In your application ...

 use ContentManager::Page;
 my $page = ContentManager::Page->create( {title=>'Extending Class::DBI', date_to_publish=>'dd/mm/yyyy'});


 my $image1 = Image->search(name=>'Class::DBI logo');
 my @figures = Image->search(name=>'Class Diagram (CDBI)', order_by => 'filename');
 my $author_image = Image->search(name=>'Aaron Trevena - portrait');

 $page->insert_Images(@figures); # inserts figures into next/last available positions, sets positions

 ...

 $page->prepend_Images($image1); # inserts image into first position, resets other image positions

 $page->append_Images($author_image); # appends image to last position

 ...

 $page->update();

DESCRIPTION

Class::DBI::Relationship::HasManyOrdered Provides an ordered 'Has Many' relationship between Class::DBI classes. This relationship enhances the HasMany relationship already provided in Class::DBI to allow you to quickly and easily deal with ordered 'One to Many' or 'Many to Many' relationships without additional handcoding while preserving as much of the original behaviour and syntax as possible.

For more information See Class::DBI and Class::DBI::Relationship.

CLASS METHODS

has_many_ordered

Page->has_many_ordered(paragraphs => Paragraphs => {sort => 'position', map => 'PageParagraphs'});

has_many_ordered is a class method which takes the accessor name, followed by the foreign class name, and a hashref of arguments. the hashref arguments self explainatory but the map argument refers to the mapping table rather than class, this differs from standard C::DBI practice but avoids the necessity of having a joining class where you would have to specify the tablename anyway

EXPORT

None.

SEE ALSO

perl

Class::DBI

Class::DBI::Relationship

AUTHOR

Aaron Trevena, <teejay@droogs.org>

Based on Class::DBI::Relationship::HasMany.

COPYRIGHT AND LICENSE

Copyright (C) 2004 by Aaron Trevena

Class::DBI::Relationship::HasMany code, etc Copyright (C) its respective authors.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.1 or, at your option, any later version of Perl 5 you may have available.