在过去24小时内按时间戳过滤结果

Question

I am trying to filter the count of Rows found, per hour, over the past 24 hours.

I am using the following SQL query and 'landtime' is a DateTime field.

SELECT HOUR(landtime) as hour, COUNT(*) as total FROM ord_log WHERE landtime > DATE_SUB(NOW(), INTERVAL 24 HOUR) GROUP BY HOUR(landtime) ORDER BY HOUR(landtime)

Sample data set > http://pastebin.com/0rYBnePG

The results looked as expected, until I looked at the data it was using.

It was pulling dates from days/weeks before todays date when I only want a count for the past 24 hours.

Any help appreciated!

Answer 1

SELECT * FROM table WHERE day(data) = EXTRACT(day FROM (NOW() - INTERVAL 1 day))

Answer 2

无需使用函数，只需使用简单的数学运算即可：

SELECT HOUR(landtime) as hour, COUNT(*) as total FROM ord_log WHERE landtime > (CURRENT_TIMESTAMP - INTERVAL 1 DAY) GROUP BY HOUR(landtime) ORDER BY HOUR(landtime)