Hi

I'm looking for a solution, to get better performance with the following
query

select first 25 RI.PLACE, SR.SWIMTIME, A.LASTNAME
from RANKINGITEM RI
join SWIMRESULT SR on SR.SWIMRESULTID = RI.SWIMRESULTID
join ATHLETE A on A.ATHLETEID = SR.ATHLETEID
where RI.RANKINGID = 589044
order by RI.PLACE

when I run this query, I have the following plan:
PLAN SORT (JOIN (RI INDEX (IX_RANKINGITEM_WORLD),SR INDEX
(PK_SWIMRESULT),A INDEX (PK_ATHLETE)))

when I look ath the statistics I have 33'000 indexed accesses to all
three tables.

When I remove the "order by" part, the query is much faster and I have
25 indexed accesses to the three tables only.

The plan is:
PLAN JOIN (RI INDEX (IX_RANKINGITEM_WORLD),SR INDEX (PK_SWIMRESULT),A
INDEX (PK_ATHLETE))

What I don't understand is, why Firebird server reads all 33'000 records
in all tables, even if the "order by" depends on RANKINGITEM only and
there is an index for that on RANKINGITEM.

Anything I can do here with a query plan or something else ?

cu Christian