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



NAME
       DBIx::Class::InflateColumn - Automatically create references from column data

SYNOPSIS
           # In your table classes
           __PACKAGE__->inflate_column('column_name', {
               inflate => sub { ... },
               deflate => sub { ... },
           });

DESCRIPTION
       This component translates column data into references, i.e. "inflating" the column data. It also
       "deflates" references into an appropriate format for the database.

       It can be used, for example, to automatically convert to and from DateTime objects for your date and
       time fields. There's a convenience component to actually do that though, try
       DBIx::Class::InflateColumn::DateTime.

       It will handle all types of references except scalar references. It will not handle scalar values,
       these are ignored and thus passed through to SQL::Abstract. This is to allow setting raw values to
       "just work". Scalar references are passed through to the database to deal with, to allow such
       settings as " \'year + 1'" and " \'DEFAULT' " to work.

       If you want to filter plain scalar values and replace them with something else, see
       DBIx::Class::FilterColumn.

METHODS
   inflate_column
       Instruct DBIx::Class to inflate the given column.

       In addition to the column name, you must provide "inflate" and "deflate" methods. The "inflate"
       method is called when you access the field, while the "deflate" method is called when the field needs
       to used by the database.

       For example, if you have a table "events" with a timestamp field named "insert_time", you could
       inflate the column in the corresponding table class using something like:

           __PACKAGE__->inflate_column('insert_time', {
               inflate => sub { DateTime::Format::Pg->parse_datetime(shift); },
               deflate => sub { DateTime::Format::Pg->format_datetime(shift); },
           });

       (Replace DateTime::Format::Pg with the appropriate module for your database, or consider
       DateTime::Format::DBI.)

       The coderefs you set for inflate and deflate are called with two parameters, the first is the value
       of the column to be inflated/deflated, the second is the row object itself. Thus you can call
       "->result_source->schema->storage->dbh" in your inflate/defalte subs, to feed to
       DateTime::Format::DBI.

       In this example, calls to an event's "insert_time" accessor return a DateTime object. This DateTime
       object is later "deflated" when used in the database layer.

   get_inflated_column
         my $val = $obj->get_inflated_column($col);

       Fetch a column value in its inflated state.  This is directly analogous to "get_column" in
       DBIx::Class::Row in that it only fetches a column already retrieved from the database, and then
       inflates it.  Throws an exception if the column requested is not an inflated column.

   set_inflated_column
         my $copy = $obj->set_inflated_column($col => $val);

       Sets a column value from an inflated value.  This is directly analogous to "set_column" in
       DBIx::Class::Row.

   store_inflated_column
         my $copy = $obj->store_inflated_column($col => $val);

       Sets a column value from an inflated value without marking the column as dirty. This is directly
       analogous to "store_column" in DBIx::Class::Row.

SEE ALSO
       DBIx::Class::Core - This component is loaded as part of the "core" DBIx::Class components; generally
       there is no need to load it directly

AUTHOR
       Matt S. Trout <mst@shadowcatsystems.co.uk>

CONTRIBUTORS
       Daniel Westermann-Clark <danieltwc@cpan.org> (documentation)

       Jess Robinson <cpan@desert-island.demon.co.uk>

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



perl v5.12.5                                     2011-05-10                    DBIx::Class::InflateColumn(3)