1.结果是百分比的
concat(rtrim(CAST(count_show/count_into * 100 as decimal(10,2))),'%')
2.把同一个channel_id的count_into组合成起来。
GROUP_CONCAT(count_into ORDER BY add_time ASC) AS count_into ... group by channel_id
3.取得不同game_id的时间desc的各前三条数据（分组取前三条记录）
SELECT * FROM pk_server AS s LEFT JOIN pk_game AS g ON s.server_gid=g.`game_id` WHERE server_status=1 AND (SELECT COUNT(*) FROM pk_server WHERE server_gid=s.`server_gid` AND server_opentime>s.`server_opentime` AND server_status=1)<3
4.取出每组最新的记录
SELECT * FROM(SELECT * FROM hd_tmp_cardlog ORDER BY Logtime DESC) hd_tmp_cardlog GROUP BY Rolename ORDER BY Logtime DESC;