> Is it possible to rewrite this as a top-level join, without using a subquery? > > Something along the lines of: > > SELECT em.end_item_meter_id > FROM end_item_meter em > inner join Meter_Reading mr > on em.end_Item_meter_id = mr.end_item_meter_id > INNER JOIN End_Item_Event eie > ON eie.end_Item_Event_Id = mr.end_Item_event_Id > INNER JOIN End_Item_Inventory eii > ON eii.end_Item_inventory_Id = eie.end_Item_inventory_id > WHERE > eii.End_Item_Inventory_Id = 6061799 > >Does that query produce the right results for you?
Thanks for the suggestion. That does get the correct results for the SELECT. However, I really need this in an UPDATE statement. UPDATE end_item_meter SET end_item_id = ? WHERE end_item_meter_id IN (... subquery ...) I re-wrote it as a SELECT for testing and determined that it SELECT with subquery had the same performance issue as UPDATE with subquery. I don't think its possible to perform a JOIN on the subject table of an update statement. Thats why I've used subqueries in the past. Ideas? Thanks again!