mySQL，网站统计:独特的每日访问

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`)
)

为了获得每天的网页访问，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唯一的日常访问？

非常感谢！

Answer 1

将其更改为计数不同的IP，如下所示

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

如果要将null视为单个IP，则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

Answer 2

您可以将IP添加到SELECT和GROUP BY中，例如：

SELECT DATE_FORMAT(`timestamp`, "%Y-%m-%d"), IP, COUNT(*)
FROM `statistics`
GROUP BY 1, 2
ORDER BY 1 ASC