RE: SQL RAND function question

It seems most RAND() functions return [0,1) (1 is not included)

That way, rand() * N gives you integers [0,N-1].

Charles Wilt
Software Engineer
CINTAS Corporation - IT 92B
513.701.1307

wiltc@xxxxxxxxxx

-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx [mailto:midrange-l-
bounces@xxxxxxxxxxxx] On Behalf Of Adam Glauser
Sent: Wednesday, February 13, 2008 10:05 AM
To: midrange-l@xxxxxxxxxxxx
Subject: Re: SQL RAND function question

lgoodbar@xxxxxxxxxxxxxx wrote:

Have you filed a PMR? This is reproducible.

<snip>

exec sql insert into loyd/randno (number)
values(cast(rand()*11 as decimal(2,0)));

<snip>

Results in SQL:
select number, count(*) from loyd/randno group by number order by 1

....+....1....+....2....+....3
NUMBER COUNT ( * )
0 90,751
1 90,312
2 91,026
3 90,885
4 91,061
5 91,168
6 90,453
7 91,287
8 90,914
9 90,861
10 91,245
11 37
******** End of data ********

This is to be expected given the way RAND() works in DB2. It could be
clearer in the documentation, but if you see my earlier post
http://archive.midrange.com/midrange-l/200802/msg00481.html and Chuck's
post http://archive.midrange.com/midrange-l/200802/msg00496.html, I
think your results will make more sense. In your case, since you are
truncating the result of the multiplication by using cast(), 11 will
only show up if RAND() returned _exactly_ 1.
--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing
list
To post a message email: MIDRANGE-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/midrange-l.

This e-mail transmission contains information that is intended to be confidential and privileged. If you receive this e-mail and you are not a named addressee you are hereby notified that you are not authorized to read, print, retain, copy or disseminate this communication without the consent of the sender and that doing so is prohibited and may be unlawful. Please reply to the message immediately by informing the sender that the message was misdirected. After replying, please delete and otherwise erase it and any attachments from your computer system. Your assistance in correcting this error is appreciated.