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Class::DBI::Loader::Relationship.3pm

NAME

Class::DBI::Loader::Relationship - Easier relationship specification in CDBI::L

SYNOPSIS

   use Class::DBI::Loader::Relationship;
 
   my $loader = Class::DBI::Loader->new( dsn => "mysql:beerdb",
                                         namespace => "BeerDB");
 
 

Now instead of saying

     BeerDB::Brewery->has_many(beers => "BeerDB::Beer");
     BeerDB::Beer->has_a(brewery => "BeerDB::Brewery");
 
     BeerDB::Handpump->has_a(beer => "BeerDB::Beer"); 
     BeerDB::Handpump->has_a(pub => "BeerDB::Pub");
     BeerDB::Pub->has_many(beers => [ BeerDB::Handpump => 'beer' ]);
     BeerDB::Beer->has_many(pubs => [ BeerDB::Handpump => 'pub' ]);
 
 

Just say

     $loader->relationship( "a brewery produces beers" );
     $loader->relationship( "a pub has beers on handpumps" );
 
 

DESCRIPTION

This module acts as a mix-in, adding the "relationship" method to "Class::DBI::Loader". Since "Class::DBI::Loader" knows how to map between table names and class names, there ought to be no need to replicate the names.

In addition, it is common (but not universal) to want reverse relationships defined for has-many relationships, and for has-a relationships to be defined for the linkages surrounding a many-to-many table.

The aim of "CDBIL::Relationship" is to simplify the declaration of common database relationships by providing both of these features.

The "relationship" takes a string. It recognises table names (singular or plural, for convenience) and extracts them from the ``sentence''.

AUTHOR

Simon Cozens, "simon@cpan.org"

SEE ALSO

Class::DBI::Loader.