Oracle数字函数

取整函数（ceil 向上取整,floor 向下取整）   select ceil(66.6) N1,floor(66.6) N2 from dual; 67 66

 取幂(power) 和 求平方根(sqrt)   select power(3,2) N1,sqrt(9) N2 from dual;9 3

求余   select mod(9,5) from dual; 4

返回固定小数位数 (round:四舍五入，trunc:直接截断)    select round(66.667,2) N1,trunc(66.667,2) N2 from dual;      66.67  66.66

返回值的符号(正数返回为1,负数为-1)   select sign(-32),sign(293) from dual;-1  1