mysql row to column with group_concat and count?

Question

i have 2 tables, users and follows. table follows has a column named status. I would like to count how many follows each user has grouping by the status.

The query below returns a record for each status type for each user.

SELECT users.name as user_name, f.status, count(f.id) 
FROM users
JOIN application_follows f ON f.user_id = users.id
GROUP BY users.id, f.status
ORDER BY users.id

returns something like:

user_name     status     count

mike          new         10
mike          old         5
tom           new         8
tom           old         9

but i would like something more friendly like:

user_name     new    old

mike          10      5
tom           8       9

tried using group_concat and count but didnt work. Any clues?

John Woo · Accepted Answer · 2012-12-19T01:43:37.780

SELECT  user_name, 
        MAX(CASE WHEN status = 'new' THEN totalFollowers ELSE NULL END) `NEW`,
        MAX(CASE WHEN status = 'old' THEN totalFollowers ELSE NULL END) `OLD`
FROM
    (
        SELECT  users.name as user_name, 
                f.status, 
                count(f.id) totalFollowers 
        FROM    users
                LEFT JOIN application_follows f 
                    ON f.user_id = users.id
        GROUP BY users.id, f.status
    ) derivedTable
GROUP BY user_name

or maybe (not sure about this one)

SELECT  users.name as user_name, 
        MAX(CASE WHEN f.status = 'new' THEN count(f.id) ELSE NULL END) `NEW`, 
        MAX(CASE WHEN f.status = 'old' THEN count(f.id) ELSE NULL END) `OLD`
FROM    users
        LEFT JOIN application_follows f 
            ON f.user_id = users.id
GROUP BY users.id, f.status

mysql row to column with group_concat and count?

1 Answers1