oracle mon和month,oracle函数（日期时间表示）

author:skate

time:2010-06-09

oracle函数(日期时间表示)

1. y,yy,yyy,yyyy表示年的最后一位，二位，三位和四位

SQL> select to_char(sysdate,'y') from dual;

TO_CHAR(SYSDATE,'Y')

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0

SQL> select to_char(sysdate,'yy') from dual;

TO_CHAR(SYSDATE,'YY')

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10

SQL> select to_char(sysdate,'yyy') from dual;

TO_CHAR(SYSDATE,'YYY')

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010

SQL> select to_char(sysdate,'yyyy') from dual;

TO_CHAR(SYSDATE,'YYYY')

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2010

SQL>

2. d：一周的第几天；dd：一个月的第几天；ddd：一年的第几天

SQL> select to_char(sysdate,'d') from dual;

TO_CHAR(SYSDATE,'D')

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4

SQL> select to_char(sysdate,'dd') from dual;

TO_CHAR(SYSDATE,'DD')

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