Oracle存储过程获取YYYY-MM-DD的时间格式

SQL> select sysdate from dual;

SYSDATE
-----------
2014-12-18

Executed in 0 seconds

SQL> set serveroutput on
SQL> declare
2 pro_date date;
3 begin
4 select sysdate into pro_date from dual;
5 dbms_output.put_line(pro_date);
6 end;
7 /

18-12月-14

PL/SQL procedure successfully completed

Executed in 0.016 seconds

SQL> 
SQL> declare
2 pro_date date;
3 begin
4 select sysdate into pro_date from dual;
5 dbms_output.put_line(to_char(pro_date,'yyyy-mm-dd'));
6 end;
7 /

2014-12-18

PL/SQL procedure successfully completed

Executed in 0.016 seconds

SQL> 
SQL> declare
2 pro_date date;
3 begin
4 select sysdate into pro_date from dual;
5 dbms_output.put_line(pro_date);
6 end;
7 /

18-12月-14

PL/SQL procedure successfully completed

Executed in 0 seconds

SQL> alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss';

Session altered

Executed in 0.015 seconds

SQL> 
SQL> declare
2 pro_date date;
3 begin
4 select sysdate into pro_date from dual;
5 dbms_output.put_line(pro_date);
6 end;
7 /

2014-12-18 11:18:15

PL/SQL procedure successfully completed

Executed in 0 seconds

SQL> alter session set nls_date_format='yyyy-mm-dd';

Session altered

Executed in 0 seconds

SQL> 
SQL> declare
2 pro_date date;
3 begin
4 select sysdate into pro_date from dual;
5 dbms_output.put_line(pro_date);
6 end;
7 /

2014-12-18

PL/SQL procedure successfully completed

Executed in 0 seconds