mySQL，网站统计: unique daily visits

Question

我在数据库中有一个表statistics:

CREATE TABLE `statistics` (
  `id` INT UNSIGNED NOT NULL AUTO_INCREMENT,
  `timestamp` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
  `address` TEXT NOT NULL,
  `ip` TEXT DEFAULT NULL,
  PRIMARY KEY (`id`)
)

为了获取每日网页访问量，我使用以下查询:

SELECT DATE_FORMAT(`timestamp`, "%Y-%m-%d"), COUNT(*)
FROM `statistics`
GROUP BY 1
ORDER BY 1 ASC

如何修改查询以获得IP唯一的每日访问量？

非常感谢!

Answer 1

将其更改为计算不同的 IP，如下所示

SELECT DATE_FORMAT(`timestamp`, "%Y-%m-%d"), COUNT(DISTINCT `ip`)
FROM `statistics`
GROUP BY 1
ORDER BY 1 ASC

如果您想将 null 视为单个 IP，我们必须进行稍微不同的查询

SELECT DATE_FORMAT(`timestamp`, "%Y-%m-%d"), COUNT(DISTINCT `ip`) + SUM(ISNULL(`ip`))
FROM `statistics`
GROUP BY 1
ORDER BY 1 ASC