The database consists of the following:
- table 'artist' with columns: artistid, name
- table 'cd' with columns: cdid, artist, title
- table 'track' with columns: trackid, cd, title
+ table 'artist' with columns: artistid, name
+ table 'cd' with columns: cdid, artist, title
+ table 'track' with columns: trackid, cd, title
And these rules exists:
- one artist can have many cds
- one cd belongs to one artist
- one cd can have many tracks
- one track belongs to one cd
+ one artist can have many cds
+ one cd belongs to one artist
+ one cd can have many tracks
+ one track belongs to one cd
=head2 Installation
First make and change the directory:
- mkdir app
- cd app
+ mkdir app
+ cd app
This example uses SQLite which is a dependency of DBIx::Class, so you
shouldn't have to install extra software.
Save the following into a example.sql
- CREATE TABLE artist (
- artistid INTEGER PRIMARY KEY,
- name TEXT NOT NULL
- );
+ CREATE TABLE artist (
+ artistid INTEGER PRIMARY KEY,
+ name TEXT NOT NULL
+ );
- CREATE TABLE cd (
- cdid INTEGER PRIMARY KEY,
- artist INTEGER NOT NULL REFERENCES artist(artistid),
- title TEXT NOT NULL);
+ CREATE TABLE cd (
+ cdid INTEGER PRIMARY KEY,
+ artist INTEGER NOT NULL REFERENCES artist(artistid),
+ title TEXT NOT NULL);
- CREATE TABLE track (
- trackid INTEGER PRIMARY KEY,
- cd INTEGER NOT NULL REFERENCES cd(cdid),
- title TEXT NOT NULL) ;
+ CREATE TABLE track (
+ trackid INTEGER PRIMARY KEY,
+ cd INTEGER NOT NULL REFERENCES cd(cdid),
+ title TEXT NOT NULL) ;
and create the sqlite database file:
First, create some dirs and change working directory:
- mkdir MyDatabase
- mkdir MyDatabase/Main
+ mkdir MyDatabase
+ mkdir MyDatabase/Main
Then, create the following DBIx::Class::Schema classes:
MyDatabase/Main.pm:
-
- package MyDatabase::Main;
- use base qw/DBIx::Class::Schema/;
- __PACKAGE__->load_classes(qw/Artist Cd Track/);
+
+ package MyDatabase::Main;
+ use base qw/DBIx::Class::Schema/;
+ __PACKAGE__->load_classes(qw/Artist Cd Track/);
- 1;
+ 1;
MyDatabase/Main/Artist.pm:
- package MyDatabase::Main::Artist;
- use base qw/DBIx::Class/;
- __PACKAGE__->load_components(qw/Core/);
- __PACKAGE__->table('artist');
- __PACKAGE__->add_columns(qw/ artistid name /);
- __PACKAGE__->set_primary_key('artistid');
- __PACKAGE__->has_many('cds' => 'MyDatabase::Main::Cd');
+ package MyDatabase::Main::Artist;
+ use base qw/DBIx::Class/;
+ __PACKAGE__->load_components(qw/Core/);
+ __PACKAGE__->table('artist');
+ __PACKAGE__->add_columns(qw/ artistid name /);
+ __PACKAGE__->set_primary_key('artistid');
+ __PACKAGE__->has_many('cds' => 'MyDatabase::Main::Cd');
- 1;
+ 1;
MyDatabase/Main/Cd.pm:
- package MyDatabase::Main::Cd;
- use base qw/DBIx::Class/;
- __PACKAGE__->load_components(qw/Core/);
- __PACKAGE__->table('cd');
- __PACKAGE__->add_columns(qw/ cdid artist title/);
- __PACKAGE__->set_primary_key('cdid');
- __PACKAGE__->belongs_to('artist' => 'MyDatabase::Main::Artist');
- __PACKAGE__->has_many('tracks' => 'MyDatabase::Main::Track');
+ package MyDatabase::Main::Cd;
+ use base qw/DBIx::Class/;
+ __PACKAGE__->load_components(qw/Core/);
+ __PACKAGE__->table('cd');
+ __PACKAGE__->add_columns(qw/ cdid artist title/);
+ __PACKAGE__->set_primary_key('cdid');
+ __PACKAGE__->belongs_to('artist' => 'MyDatabase::Main::Artist');
+ __PACKAGE__->has_many('tracks' => 'MyDatabase::Main::Track');
- 1;
+ 1;
MyDatabase/Main/Track.pm:
- package MyDatabase::Main::Track;
- use base qw/DBIx::Class/;
- __PACKAGE__->load_components(qw/Core/);
- __PACKAGE__->table('track');
- __PACKAGE__->add_columns(qw/ trackid cd title/);
- __PACKAGE__->set_primary_key('trackid');
- __PACKAGE__->belongs_to('cd' => 'MyDatabase::Main::Cd');
+ package MyDatabase::Main::Track;
+ use base qw/DBIx::Class/;
+ __PACKAGE__->load_components(qw/Core/);
+ __PACKAGE__->table('track');
+ __PACKAGE__->add_columns(qw/ trackid cd title/);
+ __PACKAGE__->set_primary_key('trackid');
+ __PACKAGE__->belongs_to('cd' => 'MyDatabase::Main::Cd');
- 1;
+ 1;
=head3 Write a script to insert some records.
insertdb.pl
- #!/usr/bin/perl -w
-
- use MyDatabase::Main;
- use strict;
-
- my $schema = MyDatabase::Main->connect('dbi:SQLite:example.db');
-
- # here's some of the sql that is going to be generated by the schema
- # INSERT INTO artist VALUES (NULL,'Michael Jackson');
- # INSERT INTO artist VALUES (NULL,'Eminem');
-
- my @artists = (['Michael Jackson'], ['Eminem']);
- $schema->populate('Artist', [
- [qw/name/],
- @artists,
- ]);
-
- my %albums = (
- 'Thriller' => 'Michael Jackson',
- 'Bad' => 'Michael Jackson',
- 'The Marshall Mathers LP' => 'Eminem',
- );
-
- my @cds;
- foreach my $lp (keys %albums) {
- my $artist = $schema->resultset('Artist')->search({
- name => $albums{$lp}
- });
- push @cds, [$lp, $artist->first];
- }
-
- $schema->populate('Cd', [
- [qw/title artist/],
- @cds,
- ]);
-
-
- my %tracks = (
- 'Beat It' => 'Thriller',
- 'Billie Jean' => 'Thriller',
- 'Dirty Diana' => 'Bad',
- 'Smooth Criminal' => 'Bad',
- 'Leave Me Alone' => 'Bad',
- 'Stan' => 'The Marshall Mathers LP',
- 'The Way I Am' => 'The Marshall Mathers LP',
- );
-
- my @tracks;
- foreach my $track (keys %tracks) {
- my $cdname = $schema->resultset('Cd')->search({
- title => $tracks{$track},
- });
- push @tracks, [$cdname->first, $track];
- }
-
- $schema->populate('Track',[
- [qw/cd title/],
- @tracks,
- ]);
+ #!/usr/bin/perl -w
+
+ use MyDatabase::Main;
+ use strict;
+
+ my $schema = MyDatabase::Main->connect('dbi:SQLite:example.db');
+
+ # here's some of the sql that is going to be generated by the schema
+ # INSERT INTO artist VALUES (NULL,'Michael Jackson');
+ # INSERT INTO artist VALUES (NULL,'Eminem');
+
+ my @artists = (['Michael Jackson'], ['Eminem']);
+ $schema->populate('Artist', [
+ [qw/name/],
+ @artists,
+ ]);
+
+ my %albums = (
+ 'Thriller' => 'Michael Jackson',
+ 'Bad' => 'Michael Jackson',
+ 'The Marshall Mathers LP' => 'Eminem',
+ );
+
+ my @cds;
+ foreach my $lp (keys %albums) {
+ my $artist = $schema->resultset('Artist')->search({
+ name => $albums{$lp}
+ });
+ push @cds, [$lp, $artist->first];
+ }
+
+ $schema->populate('Cd', [
+ [qw/title artist/],
+ @cds,
+ ]);
+
+
+ my %tracks = (
+ 'Beat It' => 'Thriller',
+ 'Billie Jean' => 'Thriller',
+ 'Dirty Diana' => 'Bad',
+ 'Smooth Criminal' => 'Bad',
+ 'Leave Me Alone' => 'Bad',
+ 'Stan' => 'The Marshall Mathers LP',
+ 'The Way I Am' => 'The Marshall Mathers LP',
+ );
+
+ my @tracks;
+ foreach my $track (keys %tracks) {
+ my $cdname = $schema->resultset('Cd')->search({
+ title => $tracks{$track},
+ });
+ push @tracks, [$cdname->first, $track];
+ }
+
+ $schema->populate('Track',[
+ [qw/cd title/],
+ @tracks,
+ ]);
=head3 Create and run the scripts
testdb.pl:
- #!/usr/bin/perl -w
-
- use MyDatabase::Main;
- use strict;
-
- my $schema = MyDatabase::Main->connect('dbi:SQLite:example.db');
-
- get_tracks_by_cd('Bad');
- get_tracks_by_artist('Michael Jackson');
-
- get_cd_by_track('Stan');
- get_cds_by_artist('Michael Jackson');
-
- get_artist_by_track('Dirty Diana');
- get_artist_by_cd('The Marshall Mathers LP');
-
-
- sub get_tracks_by_cd {
- my $cdtitle = shift;
- print "get_tracks_by_cd($cdtitle):\n";
- my $rs = $schema->resultset('Track')->search(
- {
- 'cd.title' => $cdtitle
- },
- {
- join => [qw/ cd /],
- prefetch => [qw/ cd /]
- }
- );
- while (my $track = $rs->next) {
- print $track->title . "\n";
- }
- print "\n";
- }
-
- sub get_tracks_by_artist {
- my $artistname = shift;
- print "get_tracks_by_artist($artistname):\n";
- my $rs = $schema->resultset('Track')->search(
- {
- 'artist.name' => $artistname
- },
- {
- join => {
- 'cd' => 'artist'
- },
- }
- );
- while (my $track = $rs->next) {
- print $track->title . "\n";
- }
- print "\n";
- }
-
-
-
- sub get_cd_by_track {
- my $tracktitle = shift;
- print "get_cd_by_track($tracktitle):\n";
- my $rs = $schema->resultset('Cd')->search(
- {
- 'tracks.title' => $tracktitle
- },
- {
- join => [qw/ tracks /],
- }
- );
- my $cd = $rs->first;
- print $cd->title . "\n\n";
- }
-
- sub get_cds_by_artist {
- my $artistname = shift;
- print "get_cds_by_artist($artistname):\n";
- my $rs = $schema->resultset('Cd')->search(
- {
- 'artist.name' => $artistname
- },
- {
- join => [qw/ artist /],
- prefetch => [qw/ artist /]
- }
- );
- while (my $cd = $rs->next) {
- print $cd->title . "\n";
- }
- print "\n";
- }
-
-
-
- sub get_artist_by_track {
- my $tracktitle = shift;
- print "get_artist_by_track($tracktitle):\n";
- my $rs = $schema->resultset('Artist')->search(
- {
- 'tracks.title' => $tracktitle
- },
- {
+ #!/usr/bin/perl -w
+
+ use MyDatabase::Main;
+ use strict;
+
+ my $schema = MyDatabase::Main->connect('dbi:SQLite:example.db');
+
+ get_tracks_by_cd('Bad');
+ get_tracks_by_artist('Michael Jackson');
+
+ get_cd_by_track('Stan');
+ get_cds_by_artist('Michael Jackson');
+
+ get_artist_by_track('Dirty Diana');
+ get_artist_by_cd('The Marshall Mathers LP');
+
+
+ sub get_tracks_by_cd {
+ my $cdtitle = shift;
+ print "get_tracks_by_cd($cdtitle):\n";
+ my $rs = $schema->resultset('Track')->search(
+ {
+ 'cd.title' => $cdtitle
+ },
+ {
+ join => [qw/ cd /],
+ prefetch => [qw/ cd /]
+ }
+ );
+ while (my $track = $rs->next) {
+ print $track->title . "\n";
+ }
+ print "\n";
+ }
+
+ sub get_tracks_by_artist {
+ my $artistname = shift;
+ print "get_tracks_by_artist($artistname):\n";
+ my $rs = $schema->resultset('Track')->search(
+ {
+ 'artist.name' => $artistname
+ },
+ {
+ join => {
+ 'cd' => 'artist'
+ },
+ }
+ );
+ while (my $track = $rs->next) {
+ print $track->title . "\n";
+ }
+ print "\n";
+ }
+
+
+
+ sub get_cd_by_track {
+ my $tracktitle = shift;
+ print "get_cd_by_track($tracktitle):\n";
+ my $rs = $schema->resultset('Cd')->search(
+ {
+ 'tracks.title' => $tracktitle
+ },
+ {
+ join => [qw/ tracks /],
+ }
+ );
+ my $cd = $rs->first;
+ print $cd->title . "\n\n";
+ }
+
+ sub get_cds_by_artist {
+ my $artistname = shift;
+ print "get_cds_by_artist($artistname):\n";
+ my $rs = $schema->resultset('Cd')->search(
+ {
+ 'artist.name' => $artistname
+ },
+ {
+ join => [qw/ artist /],
+ prefetch => [qw/ artist /]
+ }
+ );
+ while (my $cd = $rs->next) {
+ print $cd->title . "\n";
+ }
+ print "\n";
+ }
+
+
+
+ sub get_artist_by_track {
+ my $tracktitle = shift;
+ print "get_artist_by_track($tracktitle):\n";
+ my $rs = $schema->resultset('Artist')->search(
+ {
+ 'tracks.title' => $tracktitle
+ },
+ {
join => {
'cds' => 'tracks'
- }
- }
- );
- my $artist = $rs->first;
- print $artist->name . "\n\n";
- }
-
- sub get_artist_by_cd {
- my $cdtitle = shift;
- print "get_artist_by_cd($cdtitle):\n";
- my $rs = $schema->resultset('Artist')->search(
- {
- 'cds.title' => $cdtitle
- },
- {
- join => [qw/ cds /],
- }
- );
- my $artist = $rs->first;
- print $artist->name . "\n\n";
- }
+ }
+ }
+ );
+ my $artist = $rs->first;
+ print $artist->name . "\n\n";
+ }
+
+ sub get_artist_by_cd {
+ my $cdtitle = shift;
+ print "get_artist_by_cd($cdtitle):\n";
+ my $rs = $schema->resultset('Artist')->search(
+ {
+ 'cds.title' => $cdtitle
+ },
+ {
+ join => [qw/ cds /],
+ }
+ );
+ my $artist = $rs->first;
+ print $artist->name . "\n\n";
+ }
It should output:
- get_tracks_by_cd(Bad):
- Dirty Diana
- Smooth Criminal
- Leave Me Alone
+ get_tracks_by_cd(Bad):
+ Dirty Diana
+ Smooth Criminal
+ Leave Me Alone
- get_tracks_by_artist(Michael Jackson):
- Beat it
- Billie Jean
- Dirty Diana
- Smooth Criminal
- Leave Me Alone
+ get_tracks_by_artist(Michael Jackson):
+ Beat it
+ Billie Jean
+ Dirty Diana
+ Smooth Criminal
+ Leave Me Alone
- get_cd_by_track(Stan):
- The Marshall Mathers LP
+ get_cd_by_track(Stan):
+ The Marshall Mathers LP
- get_cds_by_artist(Michael Jackson):
- Thriller
- Bad
+ get_cds_by_artist(Michael Jackson):
+ Thriller
+ Bad
- get_artist_by_track(Dirty Diana):
- Michael Jackson
+ get_artist_by_track(Dirty Diana):
+ Michael Jackson
- get_artist_by_cd(The Marshall Mathers LP):
- Eminem
+ get_artist_by_cd(The Marshall Mathers LP):
+ Eminem
=head1 Notes
projects / dbsrgits/DBIx-Class.git / commitdiff