NAME

Class::DBI::Relationship::IsA - A Class::DBI module for 'Is A' relationships

DESCRIPTION

Class::DBI::Relationship::IsA Provides an Is A relationship between Class::DBI classes. This should DTRT when you specify an IsA relationship between classes transparently. For more information See Class::DBI and Class::DBI::Relationship.

SYNOPSIS

In your database (assuming mysql):

 create table person (
   personid int primary key auto_increment,
   firstname varchar(32),
   initials varchar(16),
   surname varchar(64),
   date_of_birth datetime
 );

 create table artist (
   artistid int primary key auto_increment,
   alias varchar(128),
   person int
 );

In your classes:

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

 Music::DBI->connection('dbi:mysql:dbname', 'username', 'password');

Superclass:

 package Music::Person;
 use base 'Music::DBI';

 Music::Artist->table('person');
 Music::Artist->columns(All => qw/personid firstname initials surname date_of_birth/);

Child class:

 package Music::Artist;
 use base 'Music::DBI';
 use Music::Person; # required for access to Music::Person methods

 Music::Artist->table('artist');
 Music::Artist->columns(All => qw/artistid alias/);
 Music::Artist->has_many(cds => 'Music::CD');
 Music::Artist->is_a(personid => 'Person'); # Music::Artist inherits accessors from Music::Person

... elsewhere ...

 use Music::Artist;
 my $artist = Music::Artist->create( {firstname=>'Sarah', surname=>'Geller', alias=>'Buffy'});
 $artist->initials('M');
 $artist->update();

SEE ALSO

perl

Class::DBI

Class::DBI::Relationship

AUTHOR

Richard Hundt, <richard@webtk.org.uk>

COPYRIGHT

Licensed for use, modification and distribution under the Artistic and GNU GPL licenses.

Copyright (C) 2004 by Richard Hundt and Aaron Trevena

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.