GBASE南大通用分享：GBase 8s数据库常用函数

日期时间函数

SYSDATE/CURRENT/TODAY

select sysdate as f_date from dual;
select current as f_date from dual;

> select sysdate as f_date from dual;


f_date                    

2021-06-25 08:20:24.97931

1 row(s) retrieved.

> 

> select current as f_date from dual;

f_date                  

2021-06-25 08:29:40.321

1 row(s) retrieved.

> 

> select today as f_today from dual;

f_today    

06/25/2021

1 row(s) retrieved.

> 

LAST_DAY

测试前，需要设置环境变量。

select last_day(date('02/18/2021')) as f_lastday from dual;

> select last_day(date('02/18/2021')) as f_lastday from dual;

f_lastday  

02/28/2021

1 row(s) retrieved.

> 

YEAR/MONTH/DAY

select year(date('02/18/2021')) as f_year, month(date('02/18/2021')) as f_month, day(date('02/18/2021')) as f_day from dual;

> select year(date('02/18/2021')) as f_year, month(date('02/18/2021')) as f_month, day(date('02/18/2021')) as f_day from dual;


f_year f_month  f_day 

  2021       2     18

1 row(s) retrieved.

> 

GBASE南大通用分享：WEEKDAY/QUARTER

select weekday(date('02/18/2021')) as f_weekday, quarter(date('02/18/2021')) as f_quarte from dual;

> select weekday(date('02/18/2021')) as f_weekday, quarter(date('02/18/2021')) as f_quarte from dual;

f_weekday f_quarte 

        4        1

1 row(s) retrieved.

> 

ADD_MONTH

select add_months(date('02/18/2021'), 2) as f_month1, add_months(date('02/18/2021'), -4) as f_month2 from dual;

> select add_months(date('02/18/2021'), 2) as f_month1, add_months(date('02/18/2021'), -4) as f_month2 from dual;


f_month1   f_month2   

04/18/2021 10/18/2020

1 row(s) retrieved.

> 

GBASE南大通用分享：TO_DATE

select to_date('2021-06-18 12:34:56', 'yyyy-mm-dd hh:mi:ss') as f_date from dual;

> select sysdate as f_date1, to_char(sysdate, 'mm/dd/yyyy hh12:mi:ss') as f_date2 from dual;

f_date1  2021-06-25 08:11:08.46768
f_date2  06/25/2021 08:11:08 

1 row(s) retrieved.

> 

GBASE南大通用分享：TO_CHAR

select sysdate as f_date1, to_char(sysdate, 'mm/dd/yyyy hh12:mi:ss') as f_date2 from dual;

> select sysdate as f_date1, to_char(sysdate, 'mm/dd/yyyy hh12:mi:ss') as f_date2 from dual;

f_date1  2021-06-25 08:11:08.46768
f_date2  06/25/2021 08:11:08 

1 row(s) retrieved.

>