MySQL 8.0

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create table bibliotheque  (
id int,
name varchar(20),
type_beb varchar(20)
);

insert into bibliotheque  values 
(1,'bebliotheque 1','type 1'),
(2,'bebliotheque 2','type 2'),
(3,'bebliotheque 3','type 1'),
(4,'bebliotheque 4','type 1'),
(5,'bebliotheque 5','type 3'),
(6,'bebliotheque 6','type 3'),
(7,'bebliotheque 7','type 1'),
(8,'bebliotheque 8','type 2'),
(8,'bebliotheque 9','type 4'),
(9,'bebliotheque 10','type 3'),
(10,'bebliotheque 11','type 4');

create table book  (
id int,
name varchar(20));

insert into book  values 
(1,'book1'),
(2,'book2'),
(3,'book3'),
(4,'book4');

create table x_x_bibliotheque_book (
bibliotheque_id int,
book_id int );

insert into x_x_bibliotheque_book values 
(1,1),
(1,3),
(2,1),
(2,2),
(2,4),
(3,2),
(4,1),
(4,2),
(4,3),
(4,4),
(8,1),
(7,1),
(6,2),
(5,4);

create table employers  (
id int,
name varchar(20));

insert into employers  values 
(1,'employer1'),
(2,'employer2'),
(3,'employer3'),
(4,'employer4');

create table x_x_bibliotheque_employers (
bibliotheque_id int,
employer_id int );
insert into x_x_bibliotheque_employers values 
(1,1),
(1,3),
(2,1),
(2,2),
(2,4),
(3,2),
(4,1),
(4,2),
(4,3),
(3,3),
(3,3),
(4,3),
(4,4),
(8,1),
(7,1),
(6,2),
(6,4),
(5,4);

typeBib	COUNT(bibliotheque.type_beb)	books	employers
type 1	28	book2,book4,book4,book3,book3,book3,book3,book3,book2,book2,book3,book2,book2,book1,book1,book1,book1,book1,book1,book4,book4,book2,book2,book2,book3,book1,book1,book4	employer3,employer2,employer1,employer4,employer3,employer3,employer2,employer1,employer4,employer3,employer1,employer2,employer1,employer4,employer3,employer3,employer2,employer1,employer1,employer3,employer4,employer2,employer3,employer3,employer3,employer3,employer1,employer3
type 2	10	book4,book1,book4,book4,book2,book2,book2,book1,book1,book1	employer1,employer1,employer4,employer2,employer4,employer2,employer1,employer4,employer2,employer1
type 3	4	book4,book2,book2	employer4,employer4,employer2
type 4	2	book1	employer1