# Class::DBI::Cascade::None - phpMan

## NAME
    [Class::DBI::Cascade::None] - Do nothing upon deletion

## DESCRIPTION
    This is a Cascading Delete strategy that will do nothing, leaving
    orphaned records behind.

    It is the base class for most ofther Cascade strategies, and so provides
    several important methods:

## CONSTRUCTOR
  new
            my $strategy = [Cascade::Class]->new($Relationship);

    This must be instantiated with a [Class::DBI::Relationship] object.

## METHODS
  foreign_for
            my $iterator = $strategy->foreign_for($obj);

    This will return all the objects which are foreign to $obj across the
    relationship. It's a normal [Class::DBI] search you can get the results
    either as a list or as an iterator.

  cascade
            $strategy->cascade($obj);

    Cascade across the related objects to $obj.

## WRITING NEW STRATEGIES
    Creating a Cascade strategy should be fairly simple. You usually just
    need to inherit from here, and then supply a cascade() method that does
    the required thing with the results from foreign_for().

    So, for example, [Cascade::Delete] is implemented simply as:

            package [Class::DBI::Cascade::Delete];

            use base '[Class::DBI::Cascade::None]';

            sub cascade {
                    my ($self, $obj) = @_;
                    $self->foreign_for($obj)->delete_all;
            }