--- In firebird-support@yahoogroups.com, "Ann W. Harrison"

>
> Conditions that apply to the right hand tables in left joins are
> better left in the JOIN ON clause.

I want to use parameters and AFAIK parameters can't be used in JOIN
clause.

> If you feel you really must
> put them in the WHERE clause, you must allow null values for the
> referenced fields.

I think I do!
See my original query, there I have

LEFT JOIN TAB_Graafik ON(TAB_Graafik.Tooleping = TAB_Tooleping.UID)

and in the WHERE I have condition

(((TAB_Graafik.Kuupaev<='31.10.2006')AND(TAB_Graafik.Kuupaev>='01.10.2006'))OR(TAB_Graafik.Kuupaev
IS NULL))

but this query doesn't return record from TAB_Tooleping which don't
have record in TAB_Graafik in given date range. But date range is ORed
with IS NULL condition, so it should!


ain