Re: Questioning Oracle Documentation

From: Michel Cadot <micadot{at}altern{dot}org>
Date: Sun, 11 Jul 2004 15:53:20 +0200
Message-ID: <40f145d8$0$29366$626a14ce@news.free.fr>

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> a écrit dans le message de news:ccr3ht$l16$1_at_sparta.btinternet.com...
>
> This didn't reproduce on my 9.2.0.1.
>
> null operation: 174
> simple assignment 337
> double conversion 707
>
>
>
> --
> Regards
>
> Jonathan Lewis
>

It seems that my other didn't reach the group. I repost it, sorry if it's double.

I executed the following test with versions 8.1.7.4 and 9.2.0.4 on a WinNT4SP6 box:

9.2.0.4:

n+15       ->  295
n+15.0     ->  227
c5=15      ->  732
c5=TO_CHAR ->  704
c5='15'    -> 2929
c2='15'    -> 2744
vc='15'    -> 2749

c5=TO_CHAR(TO_NUMBER('15')) -> 821
-

n+15       ->  292
n+15.0     ->  214
c5=15      ->  727
c5=TO_CHAR ->  718
c5='15'    -> 2930
c2='15'    -> 2829
vc='15'    -> 2764

c5=TO_CHAR(TO_NUMBER('15')) -> 827
-

n+15       ->  288
n+15.0     ->  213
c5=15      ->  737
c5=TO_CHAR ->  705
c5='15'    -> 2959
c2='15'    -> 2750
vc='15'    -> 2751

c5=TO_CHAR(TO_NUMBER('15')) -> 823

8.1.7.4:

n+15       ->  309
n+15.0     ->  255
c5=15      ->  747
c5=TO_CHAR -> 1048
c5='15'    -> 2610
c2='15'    -> 2405
vc='15'    -> 2388

c5=TO_CHAR(TO_NUMBER('15')) -> 1070
-

n+15       ->  303
n+15.0     ->  252
c5=15      ->  741
c5=TO_CHAR -> 1041
c5='15'    -> 2618
c2='15'    -> 3305
vc='15'    -> 2400

c5=TO_CHAR(TO_NUMBER('15')) -> 1071
-

n+15       ->  305
n+15.0     ->  248
c5=15      ->  750
c5=TO_CHAR -> 1038
c5='15'    -> 2615
c2='15'    -> 2409
vc='15'    -> 2404

c5=TO_CHAR(TO_NUMBER('15')) -> 1071

The test case was:
DECLARE c5 CHAR(5);

i PLS_INTEGER;
j PLS_INTEGER;
n NUMBER := 0;

c2 CHAR(2);
vc VARCHAR2(5);

BEGIN    BEGIN
     i := dbms_utility.get_time();

     FOR i IN 1 .. 1000000
     LOOP
       n := n + 15;
     END LOOP;

     j := dbms_utility.get_time() - i;
     dbms_output.put_line('n+15       ->' || TO_CHAR(j,'9999'));

   END;    BEGIN
     i := dbms_utility.get_time();

     FOR i IN 1 .. 1000000
     LOOP
       n := n+15.0;
     END LOOP;

     j := dbms_utility.get_time() - i;
     dbms_output.put_line('n+15.0     ->' || TO_CHAR(j,'9999'));

   END;    BEGIN
     i := dbms_utility.get_time();

     FOR i IN 1 .. 1000000
     LOOP
       c5 := 15;
     END LOOP;

     j := dbms_utility.get_time() - i;
     dbms_output.put_line('c5=15      ->' || TO_CHAR(j,'9999'));

   END;    BEGIN
     i := dbms_utility.get_time();

     FOR i IN 1 .. 1000000
     LOOP
       c5 := TO_CHAR(15);
     END LOOP;

     j := dbms_utility.get_time() - i;
     dbms_output.put_line('c5=TO_CHAR ->' || TO_CHAR(j,'9999'));

   END;    BEGIN
     i := dbms_utility.get_time();

     FOR i IN 1 .. 10000000
     LOOP
       c5 := '15';
     END LOOP;

     j := dbms_utility.get_time() - i;
     dbms_output.put_line('c5=''15''    ->' || TO_CHAR(j,'9999'));

   END;    BEGIN
     i := dbms_utility.get_time();

     FOR i IN 1 .. 10000000
     LOOP
       c2 := '15';
     END LOOP;

     j := dbms_utility.get_time() - i;
     dbms_output.put_line('c2=''15''    ->' || TO_CHAR(j,'9999'));

   END;    BEGIN
     i := dbms_utility.get_time();

     FOR i IN 1 .. 10000000
     LOOP
       vc := '15';
     END LOOP;

     j := dbms_utility.get_time() - i;
     dbms_output.put_line('vc=''15''    ->' || TO_CHAR(j,'9999'));

   END;    BEGIN
     i := dbms_utility.get_time();

     FOR i IN 1 .. 1000000
     LOOP
       c5 := TO_CHAR(TO_NUMBER('15'));
     END LOOP;

     j := dbms_utility.get_time() - i;
     dbms_output.put_line('c5=TO_CHAR(TO_NUMBER(''15'')) ->' || TO_CHAR(j,'9999'));

   END; END;
/

--
Regards
Michel Cadot

Received on Sun Jul 11 2004 - 08:53:20 CDT