Marian Aldenhövel schrieb:
> Hi,
>
>> It is very simply: WHERE column IS NOT NULL
>> Nothing more.
>
>
> And it does work fine.
>
>> There is *NO* distiction in Oracle
>
>
> (between NULL and an empty string)
>
> Which makes IS NOT NULL the safe choice. I was confused because
> other systems do make a distinction here.
There are indeed a lot of "templates" implemented in IT world. It means,
if you have worked on HP-UX, you probably will be able to handle
intuitiv on Linux and do the right things , if you write C++, you can
read Java without to learn it and so on (one of my friends said "the
life itself is copy'n'paste process"). But often that can be a trap and
then only the right way is to read the manuals. (Which is of course
always recommended , but very time expensive ).
Just for the record:
> A numeric zero is still different from a NULL value in Oracle
> is it?
I'm pretty sure, now you can easily build the test, to proof it.
>
>> It is wrong expectation. You can blindly substitute '' by NULL, in
>> that case you get 2 WHERE conditions
>> WHERE "PP_LOCK"=NULL
>> and
>> WHERE "PP_LOCK"<>NULL
>> both are wrong
>
>
> I would never have tried these. I _know_ they are wrong :-).
>
> Ciao, MM
Best regards
Maxim
Received on Mon Aug 01 2005 - 09:17:35 CDT
