MySQL 8.0

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CREATE TABLE `group_users`( group_id INT, user_id INT );
INSERT INTO `group_users` VALUES
( 1, 2),
( 1, 37),
( 1, 38),
( 3, 14),
( 8, 2),
( 8, 24),
( 8, 27);
CREATE TABLE `groups`( group_id INT, groupname VARCHAR(15) );
INSERT INTO `groups` VALUES
( 1, 'Sales'),
( 3, 'Marketing'),
( 8, 'Production ');
SELECT g.group_id, g.groupname, gu.group_members
  FROM `groups` g
  JOIN (SELECT GROUP_CONCAT(DISTINCT user_id ORDER BY user_id) 
             AS group_members, group_id
        FROM `group_users` 
       GROUP BY group_id
       HAVING COUNT(CASE WHEN user_id = 2 THEN 1 END) > 0
        ) gu
    ON g.group_id = gu.group_id 
 ORDER BY gu.group_id;
 


group_id
groupname
group_members


1
Sales
2,37,38

8
Production
2,24,27