DBIx::Class::InflateColumn - Automatically create references from column data
# In your table classes __PACKAGE__->inflate_column('column_name', { inflate => sub { ... }, deflate => sub { ... }, });
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 conveniece 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.
\'year + 1'
\'DEFAULT'
If you want to filter plain scalar values and replace them with something else, contribute a filtering component.
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.
inflate
deflate
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:
events
insert_time
__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.
->result_source->schema->storage->dbh
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.
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 retreived from the database, and then inflates it. Throws an exception if the column requested is not an 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.
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.
Matt S. Trout <mst@shadowcatsystems.co.uk>
Daniel Westermann-Clark <danieltwc@cpan.org> (documentation)
Jess Robinson <cpan@desert-island.demon.co.uk>
You may distribute this code under the same terms as Perl itself.
To install DBIx::Class, copy and paste the appropriate command in to your terminal.
cpanm
cpanm DBIx::Class
CPAN shell
perl -MCPAN -e shell install DBIx::Class
For more information on module installation, please visit the detailed CPAN module installation guide.