CD sample

This sample is based on the DBIx::Class CD example

lib/Track.pm6

use Red;

model CD { ... }
model Artist { ... }

model Track {
   has Uint    $.id       is column{ :id };
   has Uint    $.cd-id    is referencing{ CD.id };
   has Str     $.title    is column;
   has CD      $.cd       is relationship{ .cd-id };
   has Artist  $.artist   = $!cd.artist;

   ::?CLASS.^add-unique-constraint: { .cd-id, .title };
}

lib/CD.pm6

use Red;
use Track;

model Artist { ... }

model CD {
   has UInt   $.id          is column{ :id };
   has UInt   $!artist-id   is referencing{ Artist.id };
   has Str    $.title       is column;
   has UInt   $.year        is column;
   has Artist $.artist      is relationship{ .artist-id };
   has Track  @.tracks      is relationship{ .cd-id };

   ::?CLASS.^add-unique-constraint: { .artist-id, .title };
}

lib/Artist.pm6

use Red;
use CD;

model Artist {
   has UInt  $.id    is column{ :id };
   has Str:D $.name  is column{ :unique };
   has CD    @.cds   is relationship{ .artist-id };
   has Track @.songs = @!cds.flatmap: *.tracks;
}