MySQL 8.0

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/*CREATE TABLE users (
    id INTEGER AUTO_INCREMENT PRIMARY KEY,
    username VARCHAR(255)
);

INSERT INTO users (username) 
  VALUES 
    ('User 1'),
    ('User 2'),
    ('User 3'),
    ('User 4');
    
SELECT * FROM users;
    
CREATE TABLE message (
    id INTEGER AUTO_INCREMENT PRIMARY KEY,
    sender INTEGER NOT NULL,
    receiver INTEGER NOT NULL,
    text_message TEXT,
    status BOOLEAN DEFAULT 0,
    created_at TIMESTAMP DEFAULT NOW(),
    FOREIGN KEY (sender)
        REFERENCES users (id)
        ON DELETE CASCADE,
    FOREIGN KEY (receiver)
        REFERENCES users (id)
        ON DELETE CASCADE
);

INSERT INTO message (sender, receiver, text_message, status, created_at) 
  VALUES 
    (1, 2, 'Hi User 2 part 1', 1, CURRENT_TIMESTAMP - INTERVAL 5 MINUTE),
    (1, 3, 'Hi User 3 part 1', 1, CURRENT_TIMESTAMP - INTERVAL 4 MINUTE),
    (1, 2, 'Hi User 2 part 2', 1, CURRENT_TIMESTAMP - INTERVAL 3 MINUTE),
    (1, 3, 'Hi User 3 part 2', 1, CURRENT_TIMESTAMP - INTERVAL 2 MINUTE),
    (2, 1, 'Hi User 1', 0, CURRENT_TIMESTAMP - INTERVAL 1 MINUTE);
    
SELECT * FROM message;*/

CREATE TABLE posts (
    id INT(11) NOT NULL AUTO_INCREMENT,
    title varchar(255),
    PRIMARY KEY (id)
);

INSERT INTO posts (title) 
  VALUES 
    ('Post 1'),
    ('Post 2'),
    ('Post 3');

CREATE TABLE images (
   id INT(11) NOT NULL AUTO_INCREMENT,
   post_id INT(11),
   image varchar(255),
   FOREIGN KEY (post_id)
        REFERENCES posts (id)
        ON DELETE CASCADE,
   PRIMARY KEY (id)
);

INSERT INTO images (post_id, image) 
  VALUES 
    (1, 'Img 1'),
    (1, 'Img 2'),
    (2, 'Img 3');
    
SELECT * FROM images;

SELECT images.post_id, posts.title, JSON_ARRAYAGG(image) AS img FROM images 
INNER JOIN posts ON posts.id = images.post_id
GROUP BY post_id;
    
#SELECT *, JSON_ARRAYAGG(image) AS img FROM images GROUP BY post_id;

id	post_id	image
1	1	Img 1
2	1	Img 2
3	2	Img 3

post_id	title	img
1	Post 1	["Img 1", "Img 2"]
2	Post 2	["Img 3"]