NAME

SYNOPSIS

    package ParentObject;
    use base qw( Data::ObjectDriver::BaseObject );

    __PACKAGE__->install_properties({
        columns     => [ 'parent_id', 'partition_id', ... ],
        ...
        driver      => Data::ObjectDriver::Driver::DBI->new( @$GLOBAL_DB_INFO ),
        primary_key => 'parent_id',
    });

    __PACKAGE__->has_partitions(
        number     => scalar @PARTITIONS,
        get_driver => \&get_driver_by_partition,
    );

    package SomeObject;
    use base qw( Data::ObjectDriver::BaseObject );

    __PACKAGE__->install_properties({
        ...
        driver               => Data::ObjectDriver::Driver::SimplePartition->new(
                                    using => 'ParentObject'
                                ),
        primary_key          => ['parent_id', 'object_id'],
    });

DESCRIPTION

SimplePartition helps you partition objects into databases based on their association with one record of a parent class. If your classes don't meet the requirements imposed by SimplePartition, you can still write your own partitioning driver. See Data::ObjectDriver::Driver::Partition.

SUGGESTED PRACTICES

SimplePartition will load the related instance of the parent class every time it needs to find the partition for a related object. Consider using a minimal mapping class for the parent, keeping as much data as possible in other related classes. For example, if "User" were your parent class, you might keep only the user ID and other data used to find users (such as login name and email address) in "User", keeping further profile data in another "UserProfile" class.

As all the partitioned classes related to a given parent class will share the same "partition_get_driver" logic to turn a partition ID into a driver, you might put the "partition_get_driver" function in the parent class, or use a custom subclass of SimplePartition that contains and automatically specifies the "partition_get_driver" function.

USAGE

DIAGNOSTICS

• "using is required."

  The "using" parameter to the SimplePartition constructor is required to create the partitioned class's "get_driver" function. Perhaps you omitted it, or your subclass of SimplePartition did not properly specify it to its parent's constructor.

• "Bogus classname."

  The parent class name you specified in your "using" parameter does not appear to be a valid class name. If you are automatically generating parent class names, check that your method of converting strings to class names is correct.

• "Failed to load parent class: error"

  The parent class you specified in your "using" parameter could not be loaded, for the given reason. Perhaps you didn't include its location in your library path.

• "Partitioning driver not defined for partitioned class"

  The partitioned class named in the error is configured to use the SimplePartition driver but does not have a "partition_get_driver" set. Check that you intended to use SimplePartition with that class or, if you're automatically specifying the "partition_get_driver" function, that your technique is working correctly.

• "Cannot extract column from terms search terms or primary key"

  The SimplePartition driver could not determine from the given search terms or object key what the ID of the related parent record was. Check that your columns in the partitioned and parent classes share the same name, and that your application includes the parent ID in all "search()" calls for the partitioned class and instances of partitioned objects before attempting to save them.

  Optionaly you can enable a basic support of search across multiple partition by passing the 'multi_partition' arg (true value) to the search query.

• "Member of class with ID parent ID not found"

  The parent record associated with the partitioned object could not be loaded. Perhaps your application deleted the parent record without removing its associated partitioned objects first.

BUGS AND LIMITATIONS

SEE ALSO

LICENSE

AUTHOR & COPYRIGHT