SQL獲取兩個日期之間的天數

-- 獲取兩個日期之間的天數
SELECT to_number(to_date('2021-06-10', 'yyyy-MM-dd') - to_date('2021-01-01', 'yyyy-MM-dd')) AS days FROM dual;
SELECT to_number(to_date('2021-06-10', 'yyyy-MM-dd HH24:mi:ss') - to_date('2021-01-01', 'yyyy-MM-dd HH24:mi:ss')) AS days FROM dual;

-- 獲取兩個日期之間的月數
SELECT months_between(to_date('2021-06-01', 'yyyy-mm-dd'),to_date('2021-01-01', 'yyyy-mm-dd')) AS months FROM dual;
SELECT months_between(to_date('2021-06-01', 'yyyy-MM-dd HH24:mi:ss'),to_date('2021-01-01', 'yyyy-MM-dd HH24:mi:ss')) AS months FROM dual;