版权声明：来至蜀山雪松 https://blog.csdn.net/jianxia801/article/details/84781553
目录
1、获得系统时间
获取当前系统日期时间： SELECT SYSDATE() AS system_time FROM DUAL;
2、获得系统基本年月日时间
获取当前系统年月日： select current_date AS ymd FROM DUAL;
3、获得系统年份
获取当前系统年份：select year(CURRENT_DATE) AS year_value FROM DUAL; 
4、获得系统月份
获取当前系统月份：select month(CURRENT_DATE) AS month_value FROM DUAL;
5、获得系统天
获取当前系统日：select day(CURRENT_DATE) AS day_value FROM DUAL;
6、获得系统时分秒时间
获取当前系统时间：select time(SYSDATE()) AS time_value FROM DUAL;
7、分别获得系统 时、分、秒
获取当前系统小时、分钟、秒：
select HOUR(SYSDATE()) AS hour_value, MINUTE(SYSDATE()) AS minute_value,SECOND(SYSDATE()) AS second_value FROM DUAL;
8、获得系统毫秒数
获取当前系统毫秒：select MICROSECOND(SYSDATE()) AS ms_value FROM DUAL;