MySQL 8.0

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CREATE TABLE `tbl_author` (
  `id_author` int(11) NOT NULL,
  `id_user` int(11) DEFAULT NULL,
  `photo` varchar(300) COLLATE utf8_spanish2_ci DEFAULT NULL,
  `author` varchar(250) COLLATE utf8_spanish2_ci DEFAULT NULL,
  `active` tinyint(1) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_spanish2_ci;

INSERT INTO `tbl_author` (`id_author`, `id_user`, `photo`, `author`, `active`) VALUES
(1, 1, 'https://i.stack.imgur.com/AZKhu.png', 'Acaded', 1);

SELECT * FROM tbl_author;

CREATE TABLE `tbl_courses` (
  `id_course` int(11) NOT NULL,
  `id_author` int(11) DEFAULT NULL,
  `id_category` int(11) DEFAULT NULL,
  `study_program` varchar(10) COLLATE utf8_spanish2_ci DEFAULT NULL,
  `active` tinyint(1) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_spanish2_ci;

INSERT INTO `tbl_courses` (`id_course`, `id_author`, `id_category`, `study_program`, `active`) VALUES
(1, 1, 1, 'intensive', 1),
(2, 1, 1, 'proyect', 1);

SELECT * FROM tbl_courses;

CREATE TABLE `tbl_inscribed` (
  `id_inscribed` int(11) NOT NULL,
  `id_user` int(11) DEFAULT NULL,
  `id_course` int(11) DEFAULT NULL,
  `inscribed_date` datetime DEFAULT NULL,
  `status` varchar(50) COLLATE utf8_spanish2_ci DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_spanish2_ci;

INSERT INTO `tbl_inscribed` (`id_inscribed`, `id_user`, `id_course`, `inscribed_date`, `status`) VALUES
(1, 1, 1, '2021-05-23 14:00:00', 'Completed'),
(2, 1, 2, '2021-05-23 14:00:00', 'Pending');

SELECT * FROM tbl_inscribed;

CREATE TABLE `tbl_ratings` (
  `id_rating` int(11) NOT NULL,
  `id_user` int(11) DEFAULT NULL,
  `id_course` int(11) DEFAULT NULL,
  `rating` float DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_spanish2_ci;

INSERT INTO `tbl_ratings` (`id_rating`, `id_user`, `id_course`, `rating`) VALUES
(1, 1, 1, 5),
(2, 2, 2, 3);

SELECT * FROM tbl_ratings;

id_author	id_user	photo	author	active
1	1	https://i.stack.imgur.com/AZKhu.png	Acaded	1

id_course	id_author	id_category	study_program	active
1	1	1	intensive	1
2	1	1	proyect	1

id_inscribed	id_user	id_course	inscribed_date	status
1	1	1	2021-05-23 14:00:00	Completed
2	1	2	2021-05-23 14:00:00	Pending

id_rating	id_user	id_course	rating
1	1	1	5
2	2	2	3

avg_rating	valuations	total_intensive	total_proyect	enrolled_i
4	2	1	1	1