DBIx::Class::ResultSource::View(3pm) | User Contributed Perl Documentation | DBIx::Class::ResultSource::View(3pm) |
NAME¶
DBIx::Class::ResultSource::View - ResultSource object representing a view
SYNOPSIS¶
package MyApp::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 MyApp::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.
deploy_depends_on¶
__PACKAGE__->result_source_instance->deploy_depends_on( ["MyApp::Schema::Result::Year","MyApp::Schema::Result::CD"] );
Specify the views (and only the views) that this view depends on. Pass this an array reference of fully qualified result classes.
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.
OTHER METHODS¶
new¶
The constructor.
FURTHER QUESTIONS?¶
Check the list of additional DBIC resources.
COPYRIGHT AND LICENSE¶
This module is free software copyright by the DBIx::Class (DBIC) authors. You can redistribute it and/or modify it under the same terms as the DBIx::Class library.
2022-05-21 | perl v5.34.0 |