X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass.pm;h=5bfd5bc966e5a0a8f9149f16a18c8a05195e6629;hb=ef26a3929ebefc93ed94116553cfe3c7280a9579;hp=c1cc569de850e950c95ed2d4ae451ccebc196bec;hpb=126042ee4b9394c4eecc6ece49469da6fce23ba3;p=dbsrgits%2FDBIx-Class.git diff --git a/lib/DBIx/Class.pm b/lib/DBIx/Class.pm index c1cc569..5bfd5bc 100644 --- a/lib/DBIx/Class.pm +++ b/lib/DBIx/Class.pm @@ -4,68 +4,233 @@ use strict; use warnings; use vars qw($VERSION); -use base; - -$VERSION = '0.01'; - -sub load_components { - my $class = shift; - my @comp = map { "DBIx::Class::$_" } @_; - foreach my $comp (@comp) { - eval "use $comp"; - die $@ if $@; - } - no strict 'refs'; - unshift(@{"${class}::ISA"}, @comp); +use base qw/DBIx::Class::Componentised Class::Data::Accessor/; + +sub mk_classdata { shift->mk_classaccessor(@_); } +sub component_base_class { 'DBIx::Class' } + +# Always remember to do all digits for the version even if they're 0 +# i.e. first release of 0.XX *must* be 0.XX000. This avoids fBSD ports +# brain damage and presumably various other packaging systems too + +$VERSION = '0.06999_03'; + +sub MODIFY_CODE_ATTRIBUTES { + my ($class,$code,@attrs) = @_; + $class->mk_classdata('__attr_cache' => {}) + unless $class->can('__attr_cache'); + $class->__attr_cache->{$code} = [@attrs]; + return (); +} + +sub _attr_cache { + my $self = shift; + my $cache = $self->can('__attr_cache') ? $self->__attr_cache : {}; + my $rest = eval { $self->next::method }; + return $@ ? $cache : { %$cache, %$rest }; } 1; -=head1 NAME +=head1 NAME -DBIx::Class - Because the brain is a terrible thing to waste. +DBIx::Class - Extensible and flexible object <-> relational mapper. =head1 SYNOPSIS +Create a schema class called DB/Main.pm: + + package DB::Main; + 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: + + package DB::Main::Artist; + use base qw/DBIx::Class/; + + __PACKAGE__->load_components(qw/PK::Auto Core/); + __PACKAGE__->table('artist'); + __PACKAGE__->add_columns(qw/ artistid name /); + __PACKAGE__->set_primary_key('artistid'); + __PACKAGE__->has_many(cds => 'DB::Main::CD'); + + 1; + +A table class to represent a CD, which belongs to an artist, in DB/Main/CD.pm: + + package DB::Main::CD; + use base qw/DBIx::Class/; + + __PACKAGE__->load_components(qw/PK::Auto Core/); + __PACKAGE__->table('cd'); + __PACKAGE__->add_columns(qw/ cdid artist title year /); + __PACKAGE__->set_primary_key('cdid'); + __PACKAGE__->belongs_to(artist => 'DB::Main::Artist'); + + 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); + + # Query for all artists and put them in an array, + # or retrieve them as a result set object. + my @all_artists = $schema->resultset('Artist')->all; + my $all_artists_rs = $schema->resultset('Artist'); + + # Create a result set to search for artists. + # This does not query the DB. + my $johns_rs = $schema->resultset('Artist')->search( + # Build your WHERE using an SQL::Abstract structure: + { name => { like => 'John%' } } + ); + + # Execute a joined query to get the cds. + my @all_john_cds = $johns_rs->search_related('cds')->all; + + # Fetch only the next row. + my $first_john = $johns_rs->next; + + # Specify ORDER BY on the query. + my $first_john_cds_by_title_rs = $first_john->cds( + undef, + { order_by => 'title' } + ); + + # Create a result set that will fetch the artist relationship + # at the same time as it fetches CDs, using only one query. + my $millennium_cds_rs = $schema->resultset('CD')->search( + { year => 2000 }, + { prefetch => 'artist' } + ); + + 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 $new_cd = $schema->resultset('CD')->new({ title => 'Spoon' }); + $new_cd->artist($cd->artist); + $new_cd->insert; # Auto-increment primary key filled in after INSERT + $new_cd->title('Fork'); + + $schema->txn_do(sub { $new_cd->update }); # Runs the update in a transaction + + $millennium_cds_rs->update({ year => 2002 }); # Single-query bulk update + =head1 DESCRIPTION -This is a sql to oop mapper, inspired by the L framework, -and meant to support compability with it, while restructuring the -insides, and making it possible to support some new features like -self-joins, distinct, group bys and more. +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 +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. + +DBIx::Class can handle multi-column primary and foreign keys, complex +queries and database-level paging, and does its best to only query the +database in order to return something you've directly asked for. If a +resultset is used as an iterator it only fetches rows off the statement +handle as requested in order to minimise memory usage. It has auto-increment +support for SQLite, MySQL, PostgreSQL, Oracle, SQL Server and DB2 and is +known to be used in production on at least the first four, and is fork- +and thread-safe out of the box (although your DBD may not be). + +This project is still under rapid development, so features added in the +latest major release may not work 100% yet -- check the Changes if you run +into trouble, and beware of anything explicitly marked EXPERIMENTAL. Failing +test cases are *always* welcome and point releases are put out rapidly as +bugs are found and fixed. + +Even so, we do our best to maintain full backwards compatibility for published +APIs, since DBIx::Class is used in production in a number of organisations. +The test suite is quite substantial, and several developer releases are +generally made to CPAN before the -current branch is merged back to trunk for +a major release. + +The community can be found via: + + Mailing list: http://lists.rawmode.org/mailman/listinfo/dbix-class/ + + SVN: http://dev.catalyst.perl.org/repos/bast/trunk/DBIx-Class/ + + Wiki: http://dbix-class.shadowcatsystems.co.uk/ + + IRC: irc.perl.org#dbix-class + +=head1 WHERE TO GO NEXT + +L lists each task you might want help on, and +the modules where you will find documentation. + +=head1 AUTHOR + +mst: Matt S. Trout + +=head1 CONTRIBUTORS + +abraxxa: Alexander Hartmaier + +andyg: Andy Grundman + +ank: Andres Kievsky + +blblack: Brandon Black + +bluefeet: Aran Deltac + +LTJake: Brian Cassidy + +claco: Christopher H. Laco + +clkao: CL Kao + +typester: Daisuke Murase + +dkubb: Dan Kubb + +Numa: Dan Sully + +dwc: Daniel Westermann-Clark + +ningu: David Kamholz + +jesper: Jesper Krogh + +castaway: Jess Robinson -=head1 QUICKSTART +quicksilver: Jules Bean -If you're using Class::DBI, replacing +jguenther: Justin Guenther -use base qw/Class::DBI/; +captainL: Luke Saunders -with +draven: Marcus Ramberg -use base qw/DBIx::Class/; -__PACKAGE__->load_components(qw/CDBICompat Core/); +nigel: Nigel Metheringham -will probably get you started. +paulm: Paul Makepeace -If you're using AUTO_INCREMENT for your primary columns, you'll also want -yo load the approriate PK::Auto subclass - e.g. +phaylon: Robert Sedlacek -__PACKAGE__->load_components(qw/CDBICompat PK::Auto::SQLite Core/); +sc_: Just Another Perl Hacker -(with is what ::Test::SQLite does to present the Class::DBI::Test::SQLite -interface) +konobi: Scott McWhirter -If you fancy playing around with DBIx::Class from scratch, then read the docs -for ::Table and ::Relationship, +scotty: Scotty Allen -use base qw/DBIx::Class/; -__PACKAGE__->load_components(qw/Core/); +sszabo: Stephan Szabo -and have a look at t/lib/DBICTest.pm for a brief example. +Todd Lipcon -=head1 AUTHORS +wdh: Will Hawes -Matt S. Trout +gphat: Cory G Watson =head1 LICENSE