oracle日期函数部分用法

select to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') as nowTime from dual;   //日期转化为字符串   
select to_char(sysdate,'yyyy') as nowYear   from dual;   //获取时间的年   
select to_char(sysdate,'mm')    as nowMonth from dual;   //获取时间的月   
select to_char(sysdate,'dd')    as nowDay    from dual;   //获取时间的日   
select to_char(sysdate,'hh24') as nowHour   from dual;   //获取时间的时   
select to_char(sysdate,'mi')    as nowMinute from dual;   //获取时间的分   
select to_char(sysdate,'ss')    as nowSecond from dual;   //获取时间的秒

求某天是星期几

SQL> select to_char(to_date('2015-10-27','yyyy-mm-dd'),'day') from dual;

 

TO_CHA

------

星期二

 

两个日期间的天数

SQL>  select floor(sysdate - to_date('20020405','yyyymmdd')) from dual;

 

FLOOR(SYSDATE-TO_DATE('20020405','YYYYMMDD'))

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                                         4949

 

 

年月日的处理

select older_date,      
       newer_date,      
       years,      
       months,      
       abs(      
        trunc(      
         newer_date-      
         add_months( older_date,years*12+months )      
        )      
       ) days from ( select      
        trunc(months_between( newer_date, older_date )/12) YEARS,      
        mod(trunc(months_between( newer_date, older_date )),12 ) MONTHS,      
        newer_date,      
        older_date      
        from ( 
              select hiredate older_date, add_months(hiredate,rownum)+rownum newer_date      
              from emp 
             )      
      )     

处理月份天数不定的办法      

   select to_char(add_months(last_day(sysdate) +1, -2), 'yyyymmdd'),last_day(sysdate) from dual 

http://www.htsjk.com/oracle/23813.html www.htsjk.Com true http://www.htsjk.com/oracle/23813.html NewsArticle oracle日期函数部分用法 日期和字符转换函数用法（to_date,to_char） select to_char(sysdate,yyyy-mm-dd hh24:mi:ss) as nowTime from dual; //日期转化为字符串 select to_char(sysdate,yyyy) as nowYear from dual; //获取时...