Hello, if your data are mostly static and you have a few mains objects, maybe you can have some gain while defining conditional indexes for those plus one for the rest and then slicing the query:
create index o_1x on X (start,end,id) where object_id = 1 create index o_2x on X (start,end,id) where object_id = 2 create index o_3x on X (start,end,id) where object_id = 3 create index o_4x on X (start,end,id) where object_id = 4 ... create index o_4x on X (start,end,id) where object_id not in (1,2,3,4..) I'm not sure that putting all in one index and using the BETWEEN clause as in my example is the best method though. Marc Mamin SELECT l1.id AS id1, l2.id AS id2 FROM location l1, location l2 WHERE l1.objectid = 1 AND (l2.start BETWEEN l1.start AND l1.end OR l1.start BETWEEN l2.start AND l2.end ) l1.start AND l2.start <> l2.start -- if required AND l2.start <> l2.end -- if required AND l1.id <> l2.id UNION ALL ... WHERE l1.objectid = 2 ... UNION ALL ... WHERE l1.objectid not in (1,2,3,4..)