Re: Random Number PL/SQL
From: Thomas Kyte <tkyte_at_us.oracle.com>
Date: Wed, 16 Dec 1998 21:28:26 GMT
Message-ID: <367b25e5.19652388_at_192.86.155.100>
Date: Wed, 16 Dec 1998 21:28:26 GMT
Message-ID: <367b25e5.19652388_at_192.86.155.100>
A copy of this was sent to don_at_veenet.value.net (Don Littlefield II)
(if that email address didn't require changing)
On 16 Dec 1998 11:14:14 -0800, you wrote:
>Hello,
>
>Does anyone have a simple method of generating a random
>number in PL/SQL. I would have thought there would have
>been a routine to do this, but.. I have yet to find it.
>
>Best Regards, Don
Here is one:
create or replace package random
is
pragma restrict_references( random, WNDS, RNPS );
procedure srand( new_seed in number );
function rand return number; pragma restrict_references( rand, WNDS ); procedure get_rand( r OUT number ); function rand_max( n IN number ) return number; pragma restrict_references( rand_max, WNDS); procedure get_rand_max( r OUT number, n IN number );
end random;
/
create or replace package body random
is
multiplier constant number := 22695477; increment constant number := 1; "2^32" constant number := 2 ** 32; "2^16" constant number := 2 ** 16; "0x7fff" constant number := 32767; Seed number := 1; -- procedure srand( new_seed in number ) is begin Seed := new_seed; end srand; -- function rand return number is begin seed := mod( multiplier * seed + increment, "2^32" ); return bitand( seed/"2^16", "0x7fff" ); end rand; -- procedure get_rand( r OUT number ) is begin r := rand; end get_rand; -- function rand_max( n IN number ) return number is begin return mod( rand, n ) + 1; end rand_max; -- procedure get_rand_max( r OUT number, n IN number ) is begin r := rand_max( n ); end get_rand_max;
-- begin select userenv( 'SESSIONID' ) into seed from dual; end random; / Thomas Kyte tkyte_at_us.oracle.com Oracle Service Industries Reston, VA USA -- http://govt.us.oracle.com/ -- downloadable utilities ---------------------------------------------------------------------------- Opinions are mine and do not necessarily reflect those of Oracle Corporation Anti-Anti Spam Msg: if you want an answer emailed to you, you have to make it easy to get email to you. Any bounced email will be treated the same way i treat SPAM-- I delete it.Received on Wed Dec 16 1998 - 22:28:26 CET