Try this
select
min(T.Data)
from Turno T
LEFT join
MaquinaOcupacao MO on (MO.TurnoID = T.TurnoID)
where
T.Data > '2002-12-01' and
MO.MaquinaID = 17

Adapt your result plan for table Turno to index SK_TURNO_DATA
PLAN(T INDEX (SK_TURNO_DATA))

> Hi people,
>
> I have a database with Dialect 1 and 8K Page Size running on my

development

> machine that is a PIII 1GHZ 256 MB RAM on Windows XP. I need to run the
> following query:
>
> select
> min(T.Data)
> from
> Turno T join
> MaquinaOcupacao MO on (MO.TurnoID = T.TurnoID)
> where
> T.Data > '2002-12-01' and
> MO.MaquinaID = 17
>
> Wich should return
> '2002-12-02' for this case...
>
> the execution plan is:
> PLAN JOIN (MO INDEX (RDB$FOREIGN209),T INDEX

(RDB$PRIMARY206,SK_TURNO_DATA))



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