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A copy of this was sent to "Volker Krüger" <Gadgo_at_t-online.de>
(if that email address didn't require changing)
On Tue, 1 Jun 1999 22:14:06 +0200, you wrote:
>
>Hi,
>
>Can somebody help?
>I am looking for a random function for Oracle.
>Does anybody know of one? Or has written some code?
>
>Thx!!!
>
>Volker
In Oracle8.0 and up there is a package dbms_random you can use.
In 7.3 and before the following works:
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;
select userenv( 'SESSIONID' ) into seed from dual;
end random;
/
See http://www.oracle.com/ideveloper/ for my column 'Digging-in to Oracle8i'...
Thomas Kyte
tkyte_at_us.oracle.com
Oracle Service Industries
Reston, VA USA
--
Opinions are mine and do not necessarily reflect those of Oracle Corporation
Received on Wed Jun 02 1999 - 13:24:03 CDT