Mario Oberrauch wrote:

> hi there,
> 
> i've just tried the following:
> SELECT whatever FROM table WHERE column <> '1'
> revealing that no rows are returned that have column=NULL.
> 
> Defenitly it's simple to work-around with an "OR IS NULL", 
> but im quite
> unsure how this fits. My way to come was "everything is other than '1'
> except '1', therefore an undefined value is also other than '1'". 
> 
> i may be wrong (and it seems i am - the hours to figure that out speak
> for themselfs), so, somebody can give a hint what's truth about?

We had a discussion in this list concerning NULL-values some weeks ago.
But the fact is (SQL-standard and implementation in SAP DB and other DBMS)
that NULL compared to something will never result in 'true'.

The only chance to check NULL-values is to specifiy     col IS NULL
resp.    col IS NOT NULL
--> in your case
where column <> '1'  or column IS NULL

Elke
SAP Labs Berlin
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