Onhand Quantity at given date

Below is the query that can help in getting onhand quantity at given date. The query inputs the Item ID, organization ID and date.

SELECT   SUM (target_qty)
       , item_id
FROM     (SELECT   moqv.subinventory_code subinv
                 , moqv.inventory_item_id item_id
                 , SUM (transaction_quantity) target_qty
          FROM     mtl_onhand_qty_cost_v moqv
          WHERE    moqv.organization_id = :org_id
          AND      moqv.inventory_item_id = :item_id
          GROUP BY moqv.subinventory_code
                 , moqv.inventory_item_id
                 , moqv.item_cost
          UNION
          SELECT   mmt.subinventory_code subinv
                 , mmt.inventory_item_id item_id
                 , -SUM (primary_quantity) target_qty
          FROM     mtl_material_transactions mmt
                 , mtl_txn_source_types mtst
          WHERE    mmt.organization_id = :org_id
          AND      transaction_date >= TO_DATE (:hist_date) + 1
          AND      mmt.transaction_source_type_id =
                                               mtst.transaction_source_type_id
          AND      mmt.inventory_item_id = :item_id
          GROUP BY mmt.subinventory_code
                 , mmt.inventory_item_id) oq
GROUP BY oq.item_id