PL/SQL中的DateDiff

Question

如何在几秒钟内找到两个时间戳之间的差异？

是否有任何系统的功能，或者我应该手动计算这样

SELECT t1_id, 
EXTRACT(Day FROM(mod_date_time – create_date_time) DAY TO SECOND) as Day, 
EXTRACT(HOUR FROM(mod_date_time – create_date_time) DAY TO SECOND) as Hour, 
EXTRACT(Minute FROM(mod_date_time – create_date_time) DAY TO SECOND) as Minute, 
EXTRACT(SECOND FROM(mod_date_time – create_date_time) DAY TO SECOND) as second 
FROM t1; 

Answer 1

在Oracle一些二，日期只是数字。每天是1个整数。找到秒差可以做到如下：

SELECT (mod_date_time - create_date_time) * 24 * 60 * 60 as "seconds_diff" 
FROM t1