MySQL 8.0

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select version();


version()


8.0.27


CREATE TABLE categories (main_category varchar(10), categories varchar(20));
INSERT INTO categories VALUES
   ('sport','1,3,7,8');
CREATE TABLE sport (id int, name varchar(100));
INSERT INTO sport VALUES
   (1,'Footbal'),
   (3,'Snooker'),
   (7,'Cricket'),
   (8,'AnotherSport'),
   (9,'this one is not mentioned');
SELECT 
   id, name

FROM sport
INNER JOIN categories ON 
     INSTR( CONCAT(',',categories,','), CONCAT(',',sport.id,','))>0 AND
       main_category='sport';


id
name


1
Footbal

3
Snooker

7
Cricket

8
AnotherSport


INSERT INTO sport VALUES (11,'Biljart');

UPDATE categories SET categories = '1,3,11';
SELECT 
   id, name

FROM sport
INNER JOIN categories ON 
     INSTR( CONCAT(',',categories,','), CONCAT(',',sport.id,','))>0 AND
       main_category='sport';


id
name


1
Footbal

3
Snooker

11
Biljart