oracle单行函数之数字函数

round--四舍五入函数

trunc--截断函数

mod--求余函数

round和trunc除了可以操作数字外还可以操作日期。

Demo

 SQL> select round(45.926,2),round(45.926,1),round(45.926,0),round(45.926),round(45.926,-1),round(45.926,-2)
   2  from dual
   3  ;

 ROUND(45.926,2) ROUND(45.926,1) ROUND(45.926,0) ROUND(45.926) ROUND(45.926,-1) ROUND(45.926,-2)
 --------------- --------------- --------------- ------------- ---------------- ----------------
           45.93            45.9              46            46               50                0

 SQL> select trunc(45.926,2),trunc(45.926,1),trunc(45.926,0),trunc(45.926),trunc(45.926,-1),trunc(45.926,-2)
   2  from dual;

 TRUNC(45.926,2) TRUNC(45.926,1) TRUNC(45.926,0) TRUNC(45.926) TRUNC(45.926,-1) TRUNC(45.926,-2)
 --------------- --------------- --------------- ------------- ---------------- ----------------
           45.92            45.9              45            45               40                0

 SQL> select mod(15,4) from dual;

  MOD(15,4)
 ----------
          3