+++ /dev/null
-=head1 NAME
-
-DBIx::Class::Manual::SchemaIntro - Introduction to DBIx::Class::Schema
-
-=head1 INTRODUCTION
-
-This document describes how to set up DBIx::Class using the recommended
-schema-based approach.
-
-=head2 Setup
-
-First, you should create your base schema class, which inherits from
-L<DBIx::Class::Schema>:
-
- package My::Schema;
- use base qw/DBIx::Class::Schema/;
-
-In this class you load your result_source ("table", "model") classes, which
-we will define later, using the load_classes() method. You can specify which
-classes to load manually:
-
- # load My::Schema::Album and My::Schema::Artist
- __PACKAGE__->load_classes(qw/ Album Artist /);
-
-Or load classes by namespace:
-
- # load My::Schema::Album, My::Schema::Artist and My::OtherSchema::LinerNotes
- __PACKAGE__->load_classes(
- {
- 'My::Schema' => [qw/ Album Artist /],
- 'My::OtherSchema' => [qw/ LinerNotes /]
- }
- );
-
-Or let your schema class load all classes in its namespace automatically:
-
- # load My::Schema::*
- __PACKAGE__->load_classes();
-
-Next, create each of the classes you want to load as specified above:
-
- package My::Schema::Album;
- use base qw/DBIx::Class/;
-
-Load any components required by each class with the load_components() method.
-This should consist of "Core" plus any additional components you want to use.
-For example, if you want serial/auto-incrementing primary keys:
-
- __PACKAGE__->load_components(qw/ PK::Auto Core /);
-
-C<PK::Auto> classes exist for many databases; see
-L<DBIx::Class::PK::Auto> for more information.
-
-Set the table for your class:
-
- __PACKAGE__->table('album');
-
-Add columns to your class:
-
- __PACKAGE__->add_columns(qw/ albumid artist title /);
-
-Accessors are created for each column automatically, so My::Schema::Album will
-have albumid(), artist() and title() methods.
-
-Define a primary key for your class:
-
- __PACKAGE__->set_primary_key('albumid');
-
-If you have a multi-column primary key, just pass a list instead:
-
- __PACKAGE__->set_primary_key( qw/ albumid artistid / );
-
-=begin hide
-
-You can define relationships for any of your classes. L<DBIx::Class> will
-automatically fill in the correct namespace, so if you want to say
-"a My::Schema::Album object belongs to a My::Schema::Artist object" you do not
-need to include the namespace when declaring the relationship:
-
- __PACKAGE__->belongs_to('artist' => 'Artist');
-
-=end hide
-
-That's all you need in terms of setup.
-
-=head2 Usage
-
-In your application code, you should first create a connected schema object:
-
- my $schema = My::Schema->connect( $dsn, $user, $password, $attrs );
-
-You can create as many different schema instances as you need. So if you have
-a second database you want to access:
-
- my $other_schema = My::Schema->connect( $dsn, $user, $password, $attrs );
-
-Note that L<DBIx::Class::Schema> does not cache connnections for you. If you
-use multiple connections, you need to do this manually.
-
-To execute some sql statements on every connect you can pass them to your schema after the connect:
-
- $schema->storage->on_connect_do(\@on_connect_sql_statments);
-
-The simplest way to get a record is by primary key:
-
- my $schema = My::Schema->connect( ... );
- my $album = $schema->resultset('Album')->find(14);
-
-This will run a C<SELECT> with C<albumid = 14> in the C<WHERE> clause,
-and return an instance of C<My::Schema::Album> that represents this
-row. Once you have that row, you can access and update columns:
-
- $album->title('Physical Graffiti');
- my $title = $album->title; # holds 'Physical Graffiti'
-
-If you prefer, you can use the C<set_column> and C<get_column>
-accessors instead:
-
- $album->set_column('title', 'Presence');
- $title = $album->get_column('title');
-
-You use C<update> to commit your changes to the database:
-
- $album->update();
-
-If needed, you can throw away your local changes like this:
-
- $album->discard_changes() if $album->is_changed();
-
-As you can see, C<is_changed> allows you to check if there are local
-changes to your object.
-
-=head2 Adding and removing rows
-
-To create a new record in the database, you can use the C<create>
-method. It returns an instance of C<My::Schema::Album> that can be
-used to access the data in the new record:
-
- my $new_album = $schema->resultset('Album')->create({
- title => 'Wish You Were Here',
- artist => 'Pink Floyd'
- });
-
-Now you can add data to the new record:
-
- $new_album->label('Capitol');
- $new_album->year('1975');
- $new_album->update;
-
-Likewise, you can remove it from the database like this:
-
- $new_album->delete;
-
-You can also remove records without retrieving them first, by calling
-delete directly on a ResultSet object.
-
- # Delete all of Falco's albums
- $schema->resultset('Album')->search({ artist => 'Falco' })->delete;
-
-=head2 Finding your objects
-
-L<DBIx::Class> provides a few different ways to retrieve data from
-your database. Here's one example:
-
- # Find all of Santana's albums
- my $rs = $schema->resultset('Album')->search({ artist => 'Santana' });
-
-In scalar context, as above, C<search> returns a
-L<DBIx::Class::ResultSet> object. It can be used to peek at the first
-album returned by the database:
-
- my $album = $rs->first;
- print $album->title;
-
-Or, you can loop over the albums and update each one:
-
- while (my $album = $rs->next) {
- print $album->artist . ' - ' . $album->title;
- $album->year(2001);
- $album->update;
- }
-
-For more information on what you can do with a
-L<DBIx::Class::ResultSet>, see L<DBIx::Class::ResultSet/METHODS>.
-
-In list context, the C<search> method returns all of the matching
-rows:
-
- # Fetch immediately all of Carlos Santana's albums
- my @albums = @{ $schema->resultset('Album')->search(
- { artist => 'Carlos Santana' }
- ) };
- foreach my $album (@albums) {
- print $album->artist . ' - ' . $album->title;
- }
-
-We also provide a handy shortcut for doing a C<LIKE> search:
-
- # Find albums whose artist starts with 'Jimi'
- my $rs = $schema->resultset('Album')->search_like({ artist => 'Jimi%' });
-
-Or you can provide your own handmade C<WHERE> clause, like:
-
- # Find Peter Frampton albums from the year 1986
- my $where = 'artist = ? AND year = ?';
- my @bind = ( 'Peter Frampton', 1986 );
- my $rs = $schema->resultset('Album')->search_literal( $where, @bind );
-
-The preferred way to generate complex queries is to provide a
-L<SQL::Abstract> construct to C<search>:
-
- my $rs = $schema->resultset('Album')->search({
- artist => { '!=', 'Janis Joplin' },
- year => { '<' => 1980 },
- albumid => [ 1, 14, 15, 65, 43 ]
- });
-
-This results in something like the following C<WHERE> clause:
-
- WHERE artist != 'Janis Joplin'
- AND year < 1980
- AND albumid IN (1, 14, 15, 65, 43)
-
-For more examples of complex queries, see
-L<DBIx::Class::Manual::Cookbook>.
-
-The search can also be modified by passing another hash with
-attributes:
-
- my @albums = $schema->resultset('Album')->search(
- { artist => 'Bob Marley' },
- { rows => 2, order_by => 'year DESC' }
- );
-
-C<@albums> then holds the two most recent Bob Marley albums.
-
-For a complete overview of the available attributes, see
-L<DBIx::Class::ResultSet/ATTRIBUTES>.
-
-=head1 SEE ALSO
-
-=over 4
-
-=item * L<DBIx::Class::Manual::Cookbook>
-
-=item * L<DBIx::Class::Manual::FAQ>
-
-=back
-
-=cut
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