oracle求当年天数与当月天数

1.求当年天数的sql语句

SELECT ADD_MONTHS(TRUNC(SYSDATE, 'YYYY'), 12) - TRUNC(SYSDATE, 'YYYY') days FROM DUAL

 

2.求当月天数的sql语句

select to_number(add_months(trunc(to_date('2009-1-4 11:13:53','yyyy-fmmm-dd hh24:mi:ss'),'mm'),1)   -   trunc(to_date('2009-1-4 11:13:53','yyyy-fmmm-dd hh24:mi:ss'),'mm')) from dual;