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DBIx::Class::FilterColumn(3)         User Contributed Perl Documentation        DBIx::Class::FilterColumn(3)



NAME
       DBIx::Class::FilterColumn - Automatically convert column data

SYNOPSIS
       In your Schema or DB class add "FilterColumn" to the top of the component list.

         __PACKAGE__->load_components(qw( FilterColumn ... ));

       Set up filters for the columns you want to convert.

        __PACKAGE__->filter_column( money => {
            filter_to_storage => 'to_pennies',
            filter_from_storage => 'from_pennies',
        });

        sub to_pennies   { $_[1] * 100 }

        sub from_pennies { $_[1] / 100 }

        1;

DESCRIPTION
       This component is meant to be a more powerful, but less DWIM-y, DBIx::Class::InflateColumn.  One of
       the major issues with said component is that it only works with references.  Generally speaking
       anything that can be done with DBIx::Class::InflateColumn can be done with this component.

METHODS
   filter_column
        __PACKAGE__->filter_column( colname => {
            filter_from_storage => 'method'|\&coderef,
            filter_to_storage   => 'method'|\&coderef,
        })

       This is the method that you need to call to set up a filtered column. It takes exactly two arguments;
       the first being the column name the second being a hash reference with "filter_from_storage" and
       "filter_to_storage" set to either a method name or a code reference. In either case the filter is
       invoked as:

         $row_obj->$filter_specification ($value_to_filter)

       with $filter_specification being chosen depending on whether the $value_to_filter is being retrieved
       from or written to permanent storage.

       If a specific directional filter is not specified, the original value will be passed to/from storage
       unfiltered.

   get_filtered_column
        $obj->get_filtered_column('colname')

       Returns the filtered value of the column

   set_filtered_column
        $obj->set_filtered_column(colname => 'new_value')

       Sets the filtered value of the column

EXAMPLE OF USE
       Some databases have restrictions on values that can be passed to boolean columns, and problems can be
       caused by passing value that perl considers to be false (such as "undef").

       One solution to this is to ensure that the boolean values are set to something that the database can
       handle - such as numeric zero and one, using code like this:-__PACKAGE__->filter_column( this:__PACKAGE__->filter_column(

           __PACKAGE__->filter_column(
               my_boolean_column => {
                   filter_to_storage   => sub { $_[1] ? 1 : 0 },
               }
           );

       In this case the "filter_from_storage" is not required, as just passing the database value through to
       perl does the right thing.



perl v5.12.5                                     2010-11-29                     DBIx::Class::FilterColumn(3)