Oracle数据库中:ROUND()函数的用法:

负数表示从整数位开始四舍五入即：在小数点左侧进行四舍五入(负几就从整数的第几位开始四舍五入)；

     0表示四舍五入到最接近的整数；

     正数表示四舍五入到指定的小数位；

SQL> SELECT ROUND(-903.53567) FROM dual;

ROUND(-903.53567)

-----------------

             -904

SQL> SELECT ROUND(903.53567),ROUND(-903.53567) FROM dual;

ROUND(903.53567) ROUND(-903.53567)

---------------- -----------------

             904              -904

SQL> SELECT ROUND(903.53567),ROUND(-903.53567,-1) FROM dual;

ROUND(903.53567) ROUND(-903.53567,-1)

---------------- --------------------

             904                 -900

SQL> SELECT ROUND(903.53567),ROUND(-913.53567,-2) FROM dual;

ROUND(903.53567) ROUND(-913.53567,-2)

---------------- --------------------

             904                 -900

SQL> SELECT ROUND(903.53567),ROUND(-953.53567,-2) FROM dual;

ROUND(903.53567) ROUND(-953.53567,-2)

---------------- --------------------

             904                -1000

SQL> SELECT ROUND(903.53567),ROUND(-953.53567,-2),ROUND(903.5367,2) FROM dual;

ROUND(903.53567) ROUND(-953.53567,-2) ROUND(903.5367,2)

---------------- -------------------- -----------------

             904                -1000            903.54