Hi Bojidar,

why do you claim this would be better:

SELECT *

FROM t1 a

LEFT JOIN t2 b ON a.f1=b.f1

WHERE b.f1 IS NULL

You didn't give any proof. Did you examine what the...

What you wanted to show is a so-called exception join. But this is not a good way:

select * from t1

where t1.f1 not in (select t2.f1 from t2)

Exception joins should better...