查询最近7天每一天的数据（包括今天）

SELECT a.date,
IFNULL(pv, 0) as pv,
IFNULL(uv, 0) as uv
FROM (
SELECT date_sub(curdate(), INTERVAL 6 DAY) AS date
UNION ALL
SELECT date_sub(curdate(), INTERVAL 5 DAY) AS date
UNION ALL
SELECT date_sub(curdate(), INTERVAL 4 DAY) AS date
UNION ALL
SELECT date_sub(curdate(), INTERVAL 3 DAY) AS date
UNION ALL
SELECT date_sub(curdate(), INTERVAL 2 DAY) AS date
UNION ALL
SELECT date_sub(curdate(), INTERVAL 1 DAY) AS date
UNION ALL
SELECT date_sub(curdate(), INTERVAL 0 DAY) AS date
) a
LEFT JOIN (
SELECT date(created_time) AS datetime,
count(ip_address) AS pv,
COUNT(DISTINCT ip_address) AS uv
FROM sys_log
GROUP BY date(created_time)
) b ON a.date = b.datetime;