自定义函数比库函数速度快的例子

• 自定义
• 函数
• 库函数
• 速度快
• 例子

自定义函数比库函数速度快的例子
create or replace and compile java source named "jmath"
as
   import java.sql.*;
   import java.lang.Math.*;
  public class jmath
   {
  public static void main(String[] argv)
   {
   System.out.println("hello, java demo1");
   }
  public static int mod(int x,int y)
   {
   return x%y;
   }
  public static double log(double x,double y)
   {
   return java.lang.Math.log(y)/ java.lang.Math.log(x);
   }
  }
/
show errors java source "jmod"
create or replace procedure jmain
as
language java name 'jmath.main(java.lang.String[])';
/
create or replace function jmod(x in number,y in number)
return number
as
language java name 'jmath.mod(int ,int )return int';
/
create or replace function jlog(x in number,y in number)
return number
as
language java name 'jmath.log(double ,double )return double';
/
call dbms_java.set_output(5000);
call jmain();
select sum(log(10,rownum)) from t;
select sum(jlog(10,rownum)) from t;
SQL> select sum(log(10,rownum)) from t;
SUM(LOG(10,ROWNUM))
-------------------
         5565708.92
已用时间:  00: 00: 15.72
SQL> select sum(jlog(10,rownum)) from t;
SUM(JLOG(10,ROWNUM))
--------------------
          5565708.92
已用时间:  00: 00: 04.88