


How Can I Calculate Date Differences in MySQL Using TIMEDIFF() and TIMESTAMPDIFF()?
MySQL date difference calculation
Calculating the time difference between two dates is a common task in data processing and analysis. MySQL provides an easy way to achieve this functionality.
Syntax and return values:
MySQL uses the TIMEDIFF()
and TIMESTAMPDIFF()
functions to calculate date differences. TIMEDIFF()
Returns the difference between two dates, expressed in HH:MM:SS format. TIMESTAMPDIFF()
Allows you to specify the time unit for the result, such as seconds or milliseconds.
Usage:
To calculate the second difference, use the following syntax:
SELECT TIMESTAMPDIFF(SECOND, 开始日期, 结束日期);
To get the millisecond difference, use:
SELECT TIMESTAMPDIFF(MICROSECOND, 开始日期, 结束日期) / 1000;
Example:
Suppose you need to calculate the difference between '2007-12-31 10:02:00' and '2007-12-30 12:01:01'.
SELECT TIMEDIFF('2007-12-31 10:02:00','2007-12-30 12:01:01'); -- 结果:22:00:59 SELECT TIMESTAMPDIFF(SECOND,'2007-12-30 12:01:01','2007-12-31 10:02:00'); -- 结果:79259
As shown above, TIMESTAMPDIFF()
provides the difference in seconds, while TIMEDIFF()
displays the difference in hours, minutes, and seconds.
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