今早在看論壇時(shí)突然想起這兩個(gè)函數(shù)，所以就記錄下來，以后好參考一下

首先看一下例子：

Windows XP

orcle 9.2.0.1.0

Connected to Oracle9i Enterprise Edition Release 9.2.0.1.0
Connected as SCOTT

SQL> select ROUND(12375.989,-2) FROM DUAL;

ROUND(12375.989,-2)
-------------------
????????????? 12400

SQL> select ROUND(12335.989,-2) FROM DUAL;

ROUND(12335.989,-2)
-------------------
????????????? 12300

SQL> select TRUNC(123875.989,-2) FROM DUAL;

TRUNC(123875.989,-2)
--------------------
????????????? 123800
1. 這兩個(gè)函數(shù)都都有兩個(gè)參數(shù),如果沒有寫后面的數(shù)字那么默認(rèn)是0.

2.round(xx,number)是要四舍五入的.

3.trunc(xx,number)是不具有四舍五入的功能

ORACLE round 與 trunc 的區(qū)別