MySQL 8.0

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CREATE TABLE `case` (
  `id` int NOT NULL AUTO_INCREMENT,
  PRIMARY KEY (`id`)
); 
INSERT INTO `case` VALUES (10732),(10733),(10740);

CREATE TABLE `keyword` (
  `id` int NOT NULL AUTO_INCREMENT,
  `keyword` varchar(128) NOT NULL,
  PRIMARY KEY (`id`)
); 

INSERT INTO keyword (id,keyword) VALUES
	 (1,'sanity'),
	 (52,'automated'),
	 (118,'alm');
CREATE TABLE `case_has_keyword` (
  `case_id` int NOT NULL,
  `keyword_id` int NOT NULL,
  PRIMARY KEY (`case_id`,`keyword_id`)
); 
INSERT INTO case_has_keyword (case_id,keyword_id) VALUES
	 (10732,1),
	 (10732,52),
	 (10732,118),
	 (10740,118);

    
    
    
CREATE OR REPLACE VIEW `cases_keywords2` AS
select
    `c`.`id` AS `case_id`,
    coalesce(group_concat(`t`.`id` separator ','), '') AS `keyword_ids`,
    coalesce(group_concat(`t`.`keyword` separator ','), '') AS `keywords`
from
    (`case` `c`
left join (
    select
        `ck`.`case_id` AS `case_id`,
        `k`.`id` AS `id`,
        `k`.`keyword` AS `keyword`
    from
        (`case_has_keyword` `ck`
    join `keyword` `k` on
        ((`ck`.`keyword_id` = `k`.`id`)))) `t` on
    ((`c`.`id` = `t`.`case_id`)))
group by
    `c`.`id`;
select * from `cases_keywords2`;


case_id
keyword_ids
keywords


10732
1,52,118
sanity,automated,alm

10733



10740
1
sanity


select * from `cases_keywords2` where case_id=10740;


case_id
keyword_ids
keywords


10740
118
alm