MySQL优化海量数据

Question

我正在对具有600万行的表执行以下sql语句：

SELECT 
    log.all, max(log.created_date) as latest_date, COUNT(all) AS 
    total_count, type.id as machine_type 
FROM sms_log log, machine mac, 
    machine_type type 
WHERE mac.machine_type_id = type.id 
AND log.machine_id = mac.id 
AND log.from_machine = 1
AND log.phone_number 
    IN(SELECT data FROM machine_data 
       WHERE name = 'phonenumber' 
       AND status = 'active' 
       AND id 
           IN(SELECT machine_data_id 
              FROM machine_connector 
              WHERE connection_type = 'DATA' 
              AND status = 'active' 
              AND machine_id = mac.id)) 
GROUP BY phone_number
ORDER BY total_count DESC LIMIT 100

我已经索引了几列，但仍然需要很多时间，

帮助我优化sql！