From: Jess Robinson Date: Fri, 30 May 2008 22:41:03 +0000 (+0000) Subject: Update docs for best practices and correctness. X-Git-Tag: v0.08240~435 X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=bd077b47647c73ffb3ff5e9f015da8992263a0e9;p=dbsrgits%2FDBIx-Class.git Update docs for best practices and correctness. --- diff --git a/lib/DBIx/Class.pm b/lib/DBIx/Class.pm index 71b3c8b..705b8b0 100644 --- a/lib/DBIx/Class.pm +++ b/lib/DBIx/Class.pm @@ -63,46 +63,48 @@ The community can be found via: =head1 SYNOPSIS -Create a schema class called DB/Main.pm: +Create a schema class called MyDB/Schema.pm: - package DB::Main; + package MyDB::Schema; use base qw/DBIx::Class::Schema/; __PACKAGE__->load_classes(); 1; -Create a table class to represent artists, who have many CDs, in DB/Main/Artist.pm: +Create a table class to represent artists, who have many CDs, in +MyDB/Schema/Artist.pm: - package DB::Main::Artist; + package MyDB::Schema::Artist; use base qw/DBIx::Class/; - __PACKAGE__->load_components(qw/PK::Auto Core/); + __PACKAGE__->load_components(qw/Core/); __PACKAGE__->table('artist'); __PACKAGE__->add_columns(qw/ artistid name /); __PACKAGE__->set_primary_key('artistid'); - __PACKAGE__->has_many(cds => 'DB::Main::CD'); + __PACKAGE__->has_many(cds => 'MyDB::Schema::CD'); 1; -A table class to represent a CD, which belongs to an artist, in DB/Main/CD.pm: +A table class to represent a CD, which belongs to an artist, in +MyDB/Schema/CD.pm: - package DB::Main::CD; + package MyDB::Schema::CD; use base qw/DBIx::Class/; - __PACKAGE__->load_components(qw/PK::Auto Core/); + __PACKAGE__->load_components(qw/Core/); __PACKAGE__->table('cd'); - __PACKAGE__->add_columns(qw/ cdid artist title year /); + __PACKAGE__->add_columns(qw/ cdid artistid title year /); __PACKAGE__->set_primary_key('cdid'); - __PACKAGE__->belongs_to(artist => 'DB::Main::Artist'); + __PACKAGE__->belongs_to(artist => 'MyDB::Schema::Artist', 'artistid'); 1; Then you can use these classes in your application's code: # Connect to your database. - use DB::Main; - my $schema = DB::Main->connect($dbi_dsn, $user, $pass, \%dbi_params); + use MyDB::Schema; + my $schema = MyDB::Schema->connect($dbi_dsn, $user, $pass, \%dbi_params); # Query for all artists and put them in an array, # or retrieve them as a result set object. @@ -128,7 +130,7 @@ Then you can use these classes in your application's code: { order_by => 'title' } ); - # Create a result set that will fetch the artist relationship + # Create a result set that will fetch the artist data # at the same time as it fetches CDs, using only one query. my $millennium_cds_rs = $schema->resultset('CD')->search( { year => 2000 }, @@ -136,7 +138,7 @@ Then you can use these classes in your application's code: ); my $cd = $millennium_cds_rs->next; # SELECT ... FROM cds JOIN artists ... - my $cd_artist_name = $cd->artist->name; # Already has the data so no query + my $cd_artist_name = $cd->artist->name; # Already has the data so no 2nd query # new() makes a DBIx::Class::Row object but doesnt insert it into the DB. # create() is the same as new() then insert(). @@ -147,17 +149,18 @@ Then you can use these classes in your application's code: $schema->txn_do(sub { $new_cd->update }); # Runs the update in a transaction - $millennium_cds_rs->update({ year => 2002 }); # Single-query bulk update + # change the year of all the millennium CDs at once + $millennium_cds_rs->update({ year => 2002 }); =head1 DESCRIPTION This is an SQL to OO mapper with an object API inspired by L -(and a compatibility layer as a springboard for porting) and a resultset API +(with a compatibility layer as a springboard for porting) and a resultset API that allows abstract encapsulation of database operations. It aims to make representing queries in your code as perl-ish as possible while still providing access to as many of the capabilities of the database as possible, including retrieving related records from multiple tables in a single query, -JOIN, LEFT JOIN, COUNT, DISTINCT, GROUP BY and HAVING support. +JOIN, LEFT JOIN, COUNT, DISTINCT, GROUP BY, ORDER BY and HAVING support. DBIx::Class can handle multi-column primary and foreign keys, complex queries and database-level paging, and does its best to only query the