Oracle三个常见数字处理函数：Floor, Round, Trunc比较

• Floor(n)
  
  • 作用
    返回小于等于n的最大整数
  • 例子

SELECT FLOOR(15.1) FROM dual;

FLOOR(15.1)
-----------
         15

SELECT FLOOR(-15.1) FROM dual;

FLOOR(-15.1)
------------

SELECT FLOOR(0.1) FROM dual;

FLOOR(0.1)
----------
         0

SQL> SELECT FLOOR(0.9) FROM dual;

FLOOR(0.9)
----------
         0

SELECT FLOOR(-0.1) FROM dual;

FLOOR(-0.1)
-----------
         -1