select to_char(oiltime,'yyyy-mm-dd') from tb;--前提是oiltime在数据库中的类型是date
SQL> alter session set nls_date_format='yyyy-mm-dd';会话已更改。SQL> select sysdate from dual;SYSDATE ---------- 2010-04-17
SQL> alter session set nls_date_format = 'yyyy-mm-dd';Session altered.SQL> select hiredate from scott.emp where ename = 'SCOTT';HIREDATE ---------- 1987-04-19 alter session set nls_date_format = 'yyyy-mm-dd' 仅对当前会话有效 alter session set nls_date_format = 'yyyy-mm-dd' scope = spfile 永久修改日期格式
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2010-04-17
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1987-04-19
alter session set nls_date_format = 'yyyy-mm-dd' 仅对当前会话有效
alter session set nls_date_format = 'yyyy-mm-dd' scope = spfile 永久修改日期格式