Re: Warning about null and open question t

I really don't think Oracle needs to include functions make Oracle do stuff that *newbies* think should be in SQL.

From 7.1 on you can write your *own* functions to do whatever *you* think needs done.

Spare the bandwidth!

Sincerely,

Martin Farber
Independent Oracle Consultant "A Jack of all trades and a slave to one."

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In article MAp_at_CSUFresno.EDU, stevec_at_zimmer.CSUFresno.EDU (Steve Cosner) writes:
>In article <3rictg$r0j_at_crl2.crl.com> tactics_at_crl.com (Dewey Blaylock) writes:
>>John Jones (john_at_iluvatar.tip.duke.edu) wrote:
 <snip>
>>: I finally figured out that if both columns that were being compared were
>>: null then they were not equal. WHY????? It seems that null would be
>>: equal to null????? To any Oracle Corp. people out there ... Will this
>>: ever be fixed???
>>
>>You are exactly correct, a NULL does not equal NULL. Null is always
>>undefined. Since it has no definition it cannot be equal to another
>>undefined value. This is how NULL are treated in ORACLE and I don't
>>think it is something that needs to be fixed. One way to handle this
>>is to wrap nvl(your_column_her,0) in your cursor select or in the comparison
>>this will ensure that NULL will be handled identically.
>>
>>IF nvl(a,0) = nvl(b,0) then
>> do something;
>>END IF;
>>
>>gthomas_at_us.oracle.com
>----------------
>Watch out! The above example will fail when a=0 and b is null, and
>when a is null and b=0.
>
>The only way you can really be sure is with something like this:
> IF a = b or (a is null and b is null)
>
>Oracle's way of always returning FALSE to any comparison where a
>column value is null indicates that they don't work much in the *real*
>world. If they really wanted to help, they would come up with some
>function to be used with comparisons like:
>
> If NULLS_ARE_REAL(a=b) then do_something
>
>Such a function should treat two null values as equal, and if
>comparing < or >, nulls would always be less than anything else.
>
>How about it, Oracle???
>
>stevec_at_zimmer.csufresno.edu (Steve Cosner)
>
Received on Fri Jun 16 1995 - 00:00:00 CEST