我有一个代码,应该给我程序的编译时间,但它只给我0秒!计算错了吗?还有其他办法吗?
create or replace PROCEDURE proc_time AS
v NUMBER := 1;
x NUMBER := 0;
counter number := 0;
summ NUMBER;
ex_start NUMBER;
ex_end NUMBER;
ex_time NUMBER;
BEGIN
ex_start := dbms_utility.get_time;
while counter <= 19
loop
counter := counter + 1;
summ := x+v;
x := v;
V := summ;
dbms_output.put_line('Fibonacci nr'||counter||': '||summ);
END loop;
ex_end := DBMS_UTILITY.GET_TIME;
ex_time := (ex_end-ex_start)/100;
DBMS_OUTPUT.PUT_LINE( 'Exekveringstid: ' || ex_time || ' sekunder.' );
END;
/
答案 0 :(得分:1)
也许,它的执行速度太快了。你可以尝试将循环而不是19
的数量增加到更大的数量。
此外,它会为您提供执行时间 e,而不是编译时间。该过程已编译并存储在数据库中。输出中的时间是在运行时,即执行过程时。
例如,
SQL> CREATE OR REPLACE PROCEDURE test_time
2 AS
3 l_start NUMBER;
4 l_loops NUMBER := 10000000;
5 l_number NUMBER := 0;
6 BEGIN
7 l_start := DBMS_UTILITY.get_time;
8 FOR i IN 1 .. l_loops
9 LOOP
10 l_number := l_number + i;
11 END LOOP;
12 DBMS_OUTPUT.put_line('time taken: ' || (DBMS_UTILITY.get_time - l_start) || ' hsecs');
13 END test_time;
14 /
Procedure created.
SQL> set serveroutput on
SQL> BEGIN
2 test_time;
3 END;
4 /
time taken: 101 hsecs
PL/SQL procedure successfully completed.
SQL>
答案 1 :(得分:1)
作为替代使用TIMESTAMP
数据类型,这支持最多纳秒(假设您的服务器也支持它)
DECLARE
ex_start TIMESTAMP(9);
Duration INTERVAL DAY TO SECOND;
v NUMBER := 1;
x NUMBER := 0;
counter NUMBER := 0;
summ NUMBER;
BEGIN
ex_start := LOCALTIMESTAMP;
WHILE counter <= 10000 LOOP
counter := counter + 1;
summ := x +v;
x := v;
V := summ;
END LOOP;
Duration := LOCALTIMESTAMP - ex_start;
DBMS_OUTPUT.PUT_LINE ( EXTRACT(SECOND FROM Duration) /1000||' msec.');
END;
答案 2 :(得分:0)
正如Lalit在上面的回答中所解释的那样。你的代码片段运行得太快了 计算时差。尝试增加while循环 一些更大的数字,在这里你去!
CREATE OR REPLACE PROCEDURE proc_time
AS
v NUMBER := 1;
x NUMBER := 0;
counter NUMBER := 0;
summ NUMBER;
ex_start NUMBER;
ex_end NUMBER;
ex_time NUMBER;
BEGIN
ex_start := dbms_utility.get_time;
dbms_output.put_line('start time ==>'||NVL(ex_start,0));
WHILE counter <= 190000
LOOP
counter := counter + 1;
summ := x +v;
x := v;
V := summ;
-- dbms_output.put_line('Fibonacci nr'||counter||': '||summ);
END LOOP;
ex_end := DBMS_UTILITY.GET_TIME;
dbms_output.put_line('End time ==>'||ex_end);
ex_time := (ex_end-ex_start);
DBMS_OUTPUT.PUT_LINE( 'Exekveringstid: ' || ex_time || ' sekunder.' );
END;
set serveroutput on;
exec proc_time;
-------------------------------OUTPUT----------------------------------------
start time ==>1761607275
End time ==>1761607281
Exekveringstid: 6 sekunder.