use Bliako;

drop table if exists comment;
drop table if exists event;
drop table if exists user;

create table user (
    user_id smallint unsigned not null primary key auto_increment,
    name varchar(32) not null
);

create table event (
    event_id smallint unsigned not null primary key auto_increment,
    type enum('play','concert') not null,
    name varchar(32) not null,
    unique key type_name_uk (type, name)
);

create table comment (
    comment_id smallint unsigned not null primary key auto_increment,
    user_id smallint unsigned not null,
    event_id smallint unsigned not null,
    text blob,
    key event_id_key (event_id),
    key user_id_key (user_id),
    unique key event_user_uk (event_id, user_id),
    constraint event_id foreign key(event_id) references event (event_id),
    constraint user_id foreign key(user_id) references user (user_id)
);

insert into user values (null, 'Bliako'), (null, '1nickt');
select user_id into @bliako_id from user where name = 'Bliako';
select user_id into @1nickt_id from user where name = '1nickt';
insert into event values (null, 'play', 'Hamlet');
insert into event values (null, 'concert', 'Rolling Stones');
select event_id into @play_id from event where name ='Hamlet';
select event_id into @concert_id from event where name ='Rolling Stones';
insert into comment values
  (null, @bliako_id, @play_id, 'Somewhat depressing'),
  (null, @bliako_id, @concert_id, 'Greatest rock and roll band in the world!'),
  (null, @1nickt_id, @concert_id, 'There is cool, then there is Charlie Watts.');


##</code><code>##

$ dbicdump -o dump_directory=. Bliako::Schema 'dbi:mysql:database=Bliako'

##</code><code>##

use strict;
use warnings;
use feature 'say';
use Bliako::Schema;

my $db = Bliako::Schema->connect(
    'DBI:mysql:database=Bliako', undef, undef, { RaiseError => 1 },
);

for my $username ('Bliako', '1nickt') {
    my $user = $db->resultset('User')->search({ name => $username })->first;

    for my $comment ( $user->comments->all ) {
        say sprintf( '%s said about the %s "%s": "%s"',
                      $username,
                      $comment->event->type,
                      $comment->event->name,
                      $comment->text );
    }
}

##</code><code>##

perl -I. bliako.pl

Bliako said about the play "Hamlet": "Somewhat depressing"
Bliako said about the concert "Rolling Stones": "Greatest rock and roll band in the world!"
1nickt said about the concert "Rolling Stones": "There is cool, then there is Charlie Watts."