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  • max count with joins

    - by trixet
    I have 3 tables: users: Id Login 1 John 2 Bill 3 Jim computers: Id Name 1 Computer1 2 Computer2 3 Computer3 4 Computer4 5 Computer5 sessions: UserId ComputerId Minutes 1 2 47 2 1 32 1 4 15 2 5 5 1 2 7 1 1 40 2 5 31 I would like to display this resulting table: Login Total_sess Total_min Most_freq_computer Sess_on_most_freq Min_on_most_freq John 4 109 Computer2 2 54 Bill 3 68 Computer5 2 36 Jim - - - - - Myself I can only cover first 3 columns with: SELECT Login, COUNT(sessions.UserId), SUM(Minutes) FROM users LEFT JOIN sessions ON users.Id = sessions.UserId GROUP BY users.Id And some kind of other columns with: SELECT main.* FROM (SELECT UserId, ComputerId, COUNT(*) AS cnt ,SUM(Minutes) FROM sessions GROUP BY UserId, ComputerId) AS main INNER JOIN ( SELECT ComputerId, MAX(cnt) AS maxCnt FROM ( SELECT ComputerId, UserId, COUNT(*) AS cnt FROM sessions GROUP BY ComputerId, UserId ) AS Counts GROUP BY ComputerId) AS maxes ON main.ComputerId = maxes.ComputerId AND main.cnt = maxes.maxCnt But I need to get whole resulting table in one query. I feel I'm doing something completely wrong. Need help.

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