Question

SELECT `groups`.`name`, `groups`.`id`
FROM `groups`
JOIN `group_members`
    ON (`group_members`.`user_id` = `groups`.`user_id`)
WHERE `groups`.`user_id` = '33'
ORDER BY `groups`.`id`

I need to get group’s ID and group’s name for every group he is member in. But results can’t duplicate!

My query returns a lot of duplicate entries.

In groups are stored all groups that do exists (name, description etc.). In group_members are stored all users that are members of some group (user_id, group_id etc.).

How to modify this query to get not-duplicate, but correct results? Thanks in advice!

Edit:

In groups there are no user_id. All member of the group are stored in group_members table. I need to get all groups (group’s ID and name) where user is member.

Answer 1

If you want to know all groups of one user, you have to join on the group_members.group_id and edit the WHERE clause.

SELECT `groups`.`name`, `groups`.`id`
FROM `groups`
JOIN `group_members`
    ON (`group_members`.`group_id` = `groups`.`id`)
WHERE `group_members`.`user_id` = '33'
ORDER BY `groups`.`id`