from dual;
结果:
1、与date操作关系最大的就是两个转换函数:to_date(char[fmt[,'nls_param’]]),to_char(date[,fmt,[,nls_param...当时间为null时的用法:select to_date(null) from dual;
结果:
1.2、to_char(date[,fmt,[,nls_param]]):将日期转按一定格式换成字符类型...;
结果:
select to_char(to_date('2018-05-11','yyyy-mm-dd'),'DAY','NLS_DATE_LANGUAGE=American') from dual...select to_char(to_date(222,'J'),'Jsp') from dual;
结果:Two Hundred Twenty-Two
3、TO_TIMESTAMP(char[fmt[,...:
select trunc(decode(ww,
53,
to_date(yy || '1231', 'yyyymmdd'),
to_date(yy || '-' || to_char(ww * 7)