MySQL 8.0

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CREATE TABLE `db_user` (
  `db_user_id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL,
  `balance` decimal(10,2) NOT NULL,
  PRIMARY KEY (`db_user_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1;

CREATE TABLE `db_comment` (
  `db_comment_id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `db_user_id` int(10) unsigned NOT NULL,
  `text` text NOT NULL,
  PRIMARY KEY (`db_comment_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1;

INSERT INTO db_user(db_user_id, name, balance)
VALUES ('1','Ivan', '100');
INSERT INTO db_user(db_user_id, name, balance)
VALUES ('2','Petr', '154');
INSERT INTO db_user(db_user_id, name, balance)
VALUES ('3','Artur', '430');
INSERT INTO db_user(db_user_id, name, balance)
VALUES ('4','John', '25');

INSERT INTO db_comment(db_comment_id, db_user_id, text)
VALUES ('1','1', 'Message1 ivan');
INSERT INTO db_comment(db_comment_id, db_user_id, text)
VALUES ('2','1', 'Message2 ivan');
INSERT INTO db_comment(db_comment_id, db_user_id, text)
VALUES ('3','2', 'Message1 petr');
INSERT INTO db_comment(db_comment_id, db_user_id, text)
VALUES ('4','2', "Message2 petr");
INSERT INTO db_comment(db_comment_id, db_user_id, text)
VALUES ('5','1', 'Message3 ivan');
INSERT INTO db_comment(db_comment_id, db_user_id, text)
VALUES ('6','4', 'Message1 john');
INSERT INTO db_comment(db_comment_id, db_user_id, text)
VALUES ('7','3', 'Message1 artur');
INSERT INTO db_comment(db_comment_id, db_user_id, text)
VALUES ('8','2', 'Message3 Petr');
INSERT INTO db_comment(db_comment_id, db_user_id, text)
VALUES ('9','3', "Message2 Artur");
INSERT INTO db_comment(db_comment_id, db_user_id, text)
VALUES ('10','4', 'Message2 John');
SELECT dbu.name, (
  SELECT `text` 
  FROM db_comment dbc 
  WHERE dbu.db_user_id = dbc.db_user_id 
  ORDER BY dbc.db_comment_id DESC 
  LIMIT 1
) AS `text`
FROM db_user dbu
ORDER BY dbu.db_user_id DESC 


name
text


John
Message2 John

Artur
Message2 Artur

Petr
Message3 Petr

Ivan
Message3 ivan


SELECT dbu.name, dbc.text
FROM db_user dbu INNER JOIN (
  SELECT MAX(db_comment_id) AS db_comment_id, db_user_id
  FROM db_comment 
  GROUP BY db_user_id 
) dbc_max ON dbu.db_user_id = dbc_max.db_user_id
INNER JOIN db_comment dbc ON dbu.db_user_id = dbc_max.db_user_id 
  AND dbc.db_comment_id = dbc_max.db_comment_id
ORDER BY dbu.db_user_id DESC 


name
text


John
Message2 John

Artur
Message2 Artur

Petr
Message3 Petr

Ivan
Message3 ivan
name	text
John	Message2 John
Artur	Message2 Artur
Petr	Message3 Petr
Ivan	Message3 ivan