Re: 1 very small question for a fundamental concept.

From: <Kenneth>
Date: Sat, 04 Oct 2003 14:40:53 GMT
Message-ID: <3f7edbc8.1060565@news.inet.tele.dk>

On Sat, 04 Oct 2003 13:08:06 +0200, Jaap W. van Dijk <j.w.vandijk.removethis_at_hetnet.nl> wrote:

>On Thu, 02 Oct 2003 19:41:49 GMT, Kenneth Koenraadt wrote:
>
>...
>>
>>Any comparison operation (except "is null" and "is not null") will
>>return false when one of the operands is null.
>>
>...
>Just to nitpick: the returned value is not FALSE, but NULL. And
>because this is not TRUE, the row is not selected.
>
>Jaap.

Hi Jaap,

Confirm your observation :

SQL>
SQL> set serveroutput on;
SQL> declare

  2 ind boolean := true;
  3
  4 begin
  5
  6 ind := (1 = null);
  7 if ind is null then
  8 dbms_output.put_line('ind is NULL');   9 elsif not(ind) then
 10 dbms_output.put_line('ind is FALSE');  11 else
 12 dbms_output.put_line('ind is TRUE');  13 end if;
 14 end;
 15 /
ind is NULL

PL/SQL-procedure er udf°rt. Received on Sat Oct 04 2003 - 09:40:53 CDT