mysql - 如何计算数据库中每小时的行数？

Question

表中有两列：Datestamp如 2012-12-16 和 typedate和Timestamp12:22:59 和 type time。是否可以使用 1 个 sql 获取特定日期每小时的行数？返回时我需要获得 24 个数字。

Answer 1

像这样的东西：

SELECT COUNT(*) FROM your_table 
WHERE `Datestamp` = '2012-12-16' 
GROUP BY HOUR(`Timestamp`)

Answer 2

SELECT datestamp as day, hour(timestamp) as hour, count(*)
FROM your_table
GROUP BY datestamp, hour(timestamp)