Ann,
Thank you for your answer. I feel more confortable right now
(thinking that i was right), while my SQL knowledge is really not
strong enough to discuss any reply from senior specialists like you,
Helen and other "ténors" of this support list.
Thank you to all of you !
:-)
Olivier



--- In firebird-support@yahoogroups.com, "Ann W. Harrison"
<aharrison@i...> wrote:

> olivier_lucaes wrote:
> >
> > Hello there,
> > I not sure if this is really a bug or a logic error from my

side. If

> > anybody could reproduce...
> ...
> > [with index on TB3] returns :
> > 2
> > 3
> > 4
> >
> >
> > when no index is defined for TB3, the same select
> > returns :
> > 1
> > 2
> > 3
> > 4
> > 5
>
> Any query that returns different results when run with and without
> indexes is evidence of a bug. The problem appears to be fixed in
> Version 2. More precisely, when I run you definition scripts and
> queries I get different answers depending on the existence of

index

> IDX_TB3 with Firebird 1.03 and Firebird 1.52, but my version of

Vulcan,

> based on a very early V2 gets the same answer with and without the

index.

>
> So, my guess is 1) yes it is a bug. and 2) is fixed with the
> improvements in null handling in V2. The fix was not part of the

Vulcan

> effort ... almost nothing ... maybe nothing at all ... was done to
> indexes as part of Vulcan.
>
> Regards,
>
>
> Ann