> --- In firebird-support@yahoogroups.com, "Arno Brinkman" wrote:
> > Hi,
> >
> > The problem lies in the fact that the FB1.5.x (and earlier)
> > optimizer doesn't optimize "IS NULL / STARTING WITH" operations very
> > well. First it isn't used for the JOIN order calculation and second
> > those are not combined (when possible ofcourse) with other
> > comparisons. I'm sure the FB2 optimizer does a better job here, but
> > with using the new ODS!
> >
> > Regards,
> > Arno Brinkman
> > ABVisie
>
> Set, stop thinking of STARTING WITH as similar to BETWEEN.
>
> Thanks Arno, that explains it and means that I should add "IS NULL /
> STARTING WITH" to my mental list of things to watch out for (not
> necessarily avoid) when writing queries.

I'm curious, would the following have the same result as using STARTING
WITH? Because this is how I probably would have written it:

select p.name, d.DateOfDiagnosis
from patient p
join diagnosis d on d.patientid=p.patientid where d.diagnosis
like '206%'


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