COUNT y consulta compleja con INNER JOIN, MySQL

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drop table if exists comentario;
drop table if exists usuario;
drop table if exists spam;

create table usuario (
  id int not null primary key
);

create table comentario (
  id int not null primary key,
  id_articulo int not null,
  id_usuario int not null,
  fecha_creado datetime not null
);

create table spam (
  id int not null primary key,
  id_comentario int not null,
  id_usuario int not null
);

insert into usuario (id) values (1), (2), (3);
insert into comentario (id, id_articulo, id_usuario, fecha_creado) values
(1,11111,1, '2017-04-01 11:00:00'), (2,11111,1, '2017-04-01 10:00:00'), (3,11111,2, '2017-04-01 09:00:00'), (4,11111,2, '2017-04-01 08:00:00');
insert into spam (id, id_comentario, id_usuario) values
(1,1,3), (2,1,2);

select c.*,
       u.*,
       max(case when s.id_usuario = 1 then s.id_usuario end) as usuario_spam,
       count(s.id) as spam_count
  from comentario c
  join usuario u
    on u.id = c.id_usuario
  left join spam s
    on s.id_comentario = c.id
 where c.id_articulo = 11111
 group by c.id
 order by c.fecha_creado desc;
 
select c.*,
       u.*,
       max(case when s.id_usuario = 3 then s.id_usuario end) as usuario_spam,
       count(s.id) as spam_count
  from comentario c
  join usuario u
    on u.id = c.id_usuario
  left join spam s
    on s.id_comentario = c.id
 where c.id_articulo = 11111
 group by c.id
 order by c.fecha_creado desc;
 
drop table comentario;
drop table usuario;
drop table spam;


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