Hi,

>> Which Firebird version (1.5.1 or 1.5.3 or 2.0.0, ....) are you using.
>> Looking at the query it should work.
>
> It's 1.5.0.4290 on Linux (slack)

Ok, please give 1.5.3 a try.
IIRC there was a bug with LEFT JOINs and IS NULL, but only on specific conditions.

>> BTW, You can use parameters in the ON clause.
>
> Great, hopefully the "driver" components I use (UIB) support it too.

Yes, it will work with UIB.

Regards,
Arno Brinkman
ABVisie

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