Round()
ROUND和TRUNC
按照指定的精度进行舍入
SQL> select round(55.5),round(-55.4),trunc(55.5),trunc(-55.5) from dual;
ROUND(55.5) ROUND(-55.4) TRUNC(55.5) TRUNC(-55.5)
----------- ------------ ----------- ------------
56 -55 55 -55
select round(3.1415926,3) from dual , 3表示精度(保留小数的位数)
Trunc
按照指定的精度截取一个数
SQL> select trunc(124.1666,-2) trunc1,trunc(124.16666,2) from dual;
TRUNC1 TRUNC(124.16666,2)
--------- ------------------
100 124.16
Abs
绝对值函数
select abs(-2.36) from dual
ABS(-2.26)
----------
2.26
ABS(-2.26)
----------
2.26
Ceil
向上取值
select ceil(2.36) from dual
CEIL(2.36)
----------
3
向下取值floor
select floor(2.36) from dual
FLOOR(2.36)
-----------
2