NAME

DBIx::Class::ResultSource::View - ResultSource object representing a view

SYNOPSIS

  package MyDB::Schema::Result::Year2000CDs;

  use base qw/DBIx::Class::Core/;

  __PACKAGE__->table_class('DBIx::Class::ResultSource::View');

  __PACKAGE__->table('year2000cds');
  __PACKAGE__->result_source_instance->is_virtual(1);
  __PACKAGE__->result_source_instance->view_definition(
      "SELECT cdid, artist, title FROM cd WHERE year ='2000'"
  );
  __PACKAGE__->add_columns(
    'cdid' => {
      data_type => 'integer',
      is_auto_increment => 1,
    },
    'artist' => {
      data_type => 'integer',
    },
    'title' => {
      data_type => 'varchar',
      size      => 100,
    },
  );

DESCRIPTION

View object that inherits from DBIx::Class::ResultSource

This class extends ResultSource to add basic view support.

A view has a "view_definition", which contains a SQL query. The query can only have parameters if "is_virtual" is set to true. It may contain JOINs, sub selects and any other SQL your database supports.

View definition SQL is deployed to your database on "deploy" in DBIx::Class::Schema unless you set "is_virtual" to true.

Deploying the view does not translate it between different database syntaxes, so be careful what you write in your view SQL.

Virtual views ("is_virtual" true), are assumed to not exist in your database as a real view. The "view_definition" in this case replaces the view name in a FROM clause in a subselect.

EXAMPLES

Having created the MyDB::Schema::Year2000CDs schema as shown in the SYNOPSIS above, you can then:

  $2000_cds = $schema->resultset('Year2000CDs')
                     ->search()
                     ->all();
  $count    = $schema->resultset('Year2000CDs')
                     ->search()
                     ->count();

If you modified the schema to include a placeholder

  __PACKAGE__->result_source_instance->view_definition(
      "SELECT cdid, artist, title FROM cd WHERE year ='?'"
  );

and ensuring you have is_virtual set to true:

  __PACKAGE__->result_source_instance->is_virtual(1);

You could now say:

  $2001_cds = $schema->resultset('Year2000CDs')
                     ->search({}, { bind => [2001] })
                     ->all();
  $count    = $schema->resultset('Year2000CDs')
                     ->search({}, { bind => [2001] })
                     ->count();

SQL EXAMPLES

is_virtual set to false

  $schema->resultset('Year2000CDs')->all();

  SELECT cdid, artist, title FROM year2000cds me

is_virtual set to true

  $schema->resultset('Year2000CDs')->all();

  SELECT cdid, artist, title FROM 
    (SELECT cdid, artist, title FROM cd WHERE year ='2000') me

METHODS

is_virtual

  __PACKAGE__->result_source_instance->is_virtual(1);

Set to true for a virtual view, false or unset for a real database-based view.

view_definition

  __PACKAGE__->result_source_instance->view_definition(
      "SELECT cdid, artist, title FROM cd WHERE year ='2000'"
      );

An SQL query for your view. Will not be translated across database syntaxes.

OVERRIDDEN METHODS

from

Returns the FROM entry for the table (i.e. the view name) or the SQL as a subselect if this is a virtual view.

AUTHORS

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

With Contributions from:

Guillermo Roditi <groditi@cpan.org>

Jess Robinson <castaway@desert-island.me.uk>

Wallace Reis <wreis@cpan.org>

LICENSE

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

cpanm DBIx::Class

perl -MCPAN -e shell
install DBIx::Class