Subject AW: [Firebird-Java] Re: delete with null not executed
Author Steffen Heil
> > Issue is that NULL=NULL -> false and this is according to the SQL
> > standard.
> y, i always forgot about sounds like a bad choice... at
> least based on my experience...

Only if you abuse NULL.
NULL does not mean "no such thing", but "unknown".
Therefore, if you want to specify, that something is not existant, you need
to set a special value for this.
If you compare NULL=NULL, however, you want to know, if two things - that
you do not know at all - are equal. This is undecideable. Therefor NULL=NULL
returns false as well as NULL<>NULL returns false.



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