NAME

Alzabo::Runtime::ForeignKey - Foreign key objects

SYNOPSIS

  use Alzabo::Runtime::ForeignKey;

DESCRIPTION

Objects in this class maintain referential integrity. This is really only useful when your RDBMS can't do this itself (like MySQL). For a RDBMS that can do this, this feature can be turned off (see the Alzabo::Runtime documentation).

METHODS

• register_update ($new_value)

  This method takes the proposed new value for a column and makes sure that it is valid based on the type of relationship between the two tables.

  Exceptions:

   AlzaboReferentialIntegrityException - something about this update
   violates referential integrity.

• register_delete (Alzabo::Runtime::Row object)

  Allows the foreign key to delete rows dependent on the row being deleted. Note, this can lead to a chain reaction of cascading deletions. You have been warned.

AUTHOR

Dave Rolsky, <autarch@urth.org>