Maypole::Model::CDBI::Base - Model base class based on Class::DBI


This is a master model class which uses Class::DBI to do all the hard work of fetching rows and representing them as objects. It is a good model to copy if you're replacing it with other database abstraction modules.

It implements a base set of methods required for a Maypole Data Model.

It inherits accessor and helper methods from Maypole::Model::Base.


Adds model as superclass to model classes (if necessary)

Action Methods

Action methods are methods that are accessed through web (or other public) interface.


If there is an object in $r->objects, then it should be edited with the parameters in $r->params; otherwise, a new object should be created with those parameters, and put back into $r->objects. The template should be changed to view, or edit if there were any errors. A hash of errors will be passed to the template.


This command shows the object using the view factory template.


Deprecated method that calls do_delete or a given classes delete method, please use do_delete instead


Unsuprisingly, this command causes a database record to be forever lost.

This method replaces the, now deprecated, delete method provided in prior versions

Deprecated searching method - use do_search instead.

This action method searches for database records, it replaces the, now deprecated, search method previously provided.


The list method fills $r->objects with all of the objects in the class. The results are paged using a pager.

Helper Methods


This class method is passed the name of a model class that represents a table and allows the master model class to do any set-up required.

This method returns a list of has-many accessors. A brewery has many beers, so BeerDB::Brewery needs to return beers.

Given an accessor name as a method, this function returns the class this accessor returns.



Returns a list of columns suitable for searching - used in factory templates, over-ridden in classes. Provides same list as display_columns unless over-ridden.


Returns the hash ref of relationship meta info for a given column.


   Returns the name of the column to use when stringifying
   and object.


   Sets the pager template argument ($r->{template_args}{pager})
   to a Class::DBI::Pager object based on the rows_per_page
   value set in the configuration of the application.

   This pager is used via the pager macro in TT Templates, and
   is also accessible via Mason.


    Returns the SQL order syntax based on the order parameter passed
    to the request, and the valid columns.. i.e. 'title ASC' or 'date_created DESC'.

    $sql .= $self->order($r);

    If the order column is not a column of this table,
    or an order argument is not passed, then the return value is undefined.

    Note: the returned value does not start with a space.


Returns 1 or more objects of the given class when provided with the request


Private method to return the class a column belongs to that was inherited by an is_a relationship. This should probably be public but need to think of API


    my $type = $class->column_type('column_name');

This returns the 'type' of this column (VARCHAR(20), BIGINT, etc.) For now, it returns "BOOL" for tinyints.

TODO :: TEST with enums


  Accessor to get/set required columns for forms, validation, etc.

  Returns list of required columns. Accepts an array ref of column names.

  $class->required_columns([qw/foo bar baz/]);

  Allows you to specify the required columns for a class, over-riding any
  assumptions and guesses made by Maypole.

  Any columns specified as required will no longer be 'nullable' or optional, and
  any columns not specified as 'required' will be 'nullable' or optional.

  The default for a column is nullable, or whatever is discovered from database

  Use this instead of $config->{$table}{required_cols}

  Note : you need to setup the model class before calling this method.


  Returns true if a column is required

  my $required = $class->column_required($column_name);

  Columns can be required by the application but not the database, but not the other way around,
  hence there is also a column_nullable method which will tell you if the column is nullable
  within the database itself.


  Returns true if a column can be NULL within the underlying database and false if not.

  my $nullable = $class->column_nullable($column_name);

  Any columns that are not nullable will automatically be specified as required, you can
  also specify nullable columns as required within your application.

  It is recomended you use column_required rather than column_nullable within your
  application, this method is more useful if extending the model or handling your own


Returns default value for column or the empty string. Columns with NULL, CURRENT_TIMESTAMP, or Zeros( 0000-00...) for dates and times have '' returned.


Gets class meta data *excluding cgi input* for the passed in class or the calling class. *NOTE* excludes cgi inputs. This method is handy to call from templates when you need some metadata for a related class.


Maypole, Maypole::Model::Base.


Maypole is currently maintained by Aaron Trevena.


Simon Cozens,

Simon Flack maintained Maypole from 2.05 to 2.09

Sebastian Riedel, maintained Maypole from 1.99_01 to 2.04


You may distribute this code under the same terms as Perl itself.