1、在oracle中有很多关于日期的函数,如:1、add_months()用于从一个日期值增加或减少一些月份date_value:=add_months(date_value,number_of_months)例:SQL> select add_months(sysdate,12) "Next Year" from dual; Next Year----------13-11月-04 SQL> select add_months(sysdate,112) "Last Year" from dual; Last Year-----
2、-----13-3月 -13 SQL> 2、current_date()返回当前会放时区中的当前日期date_value:=current_dateSQL> column sessiontimezone for a15SQL> select sessiontimezone,current_date from dual; SESSIONTIMEZONE CURRENT_DA--------------- ----------+08:00 13-11月-03 SQL> alter session set
4、mestamp()以timestamp with time zone数据类型返回当前会放时区中的当前日期timestamp_with_time_zone_value:=current_timestamp([timestamp_precision])SQL> column sessiontimezone for a15SQL> column current_timestamp format a36SQL> select sessiontimezone,current_timestamp from dual; SESSIONTIME
5、ZONE CURRENT_TIMESTAMP--------------- ------------------------------------+08:00 13-11月-03 11.56.28.160000 上午 +08: 00 SQL> alter session set time_zone='-11:00' 2 / 会话已更改。 SQL> select sessiontimezone,current_timestamp from dual; SESSIONT
7、ct()找出日期或间隔值的字段值date_value:=extract(date_field from [datetime_value
8、interval_value])SQL> select extract(month from sysdate) "This Month" from dual; This Month---------- 11 SQL> select extract(year from add_months(sysdate,36)) "3 Years Out" from dual; 3 Year