DB FUNCTION call in a trigger

Question

Hello alll,
i wanna select the latest of MAX * ITEM_QTY* in WH_t_ITEMS table and update the BALANCE_QTY with the latest Quantity balance..!
My Question is i want to know:
1) is that correct...!?
ca va bien ?! :)
2) How can i call this function in a db Trigger. post insert & post-update in the wh_t_items
SQL>  desc WH_t_items
Name                                  
ITEM_SERIAL                           
STORE_ID                              
TRANSACTION_SERIAL                    
ITEM_QTY                              
UNIT_PRICE                            
ITEM_PRICE                            
BALANCE_QTY                           
IS_OPEN                               
WITHDRAW_QTY                           Here is my trial code...
CREATE OR REPLACE Function Balance_quantity_update    ( V_STORE_ID  IN NUMBER  ,  V_ITEM_SERIAL IN NUMBER   )
   RETURN NUMBER IS
    cnumber NUMBER;
    CURSOR CR_UPDATE  IS
    SELECT NVL( MAX(  ITEM_QTY ) , 0  )
     FROM WH_T_ITEMS
    WHERE STORE_ID    =  V_STORE_ID
     AND    ITEM_SERIAL  = V_ITEM_SERIAL ;      
BEGIN
OPEN CR_UPDATE  ;
FETCH CR_UPDATE   INTO cnumber;
IF CR_UPDATE%notfound then     NULL ;
ELSE
LOOP
  UPDATE  WH_T_ITEMS
        SET    BALANCE_QTY          =  cnumber
        WHERE  WH_T_ITEMS.STORE_ID  =  V_STORE_ID
        AND    ITEM_SERIAL          =  V_ITEM_SERIAL;   
END LOOP ;
END IF;
CLOSE CR_UPDATE  ;
RETURN cnumber;
EXCEPTION
WHEN OTHERS THEN
      raise_application_error(-20001,'An error was encountered - '||SQLCODE||' -ERROR- '||SQLERRM);
END Balance_quantity_update;
/Regards,
Abdetu...

Answer 1

Hi Ahmed Eid Mubarak :)
Yesss, that's would work for me but when
CREATE OR REPLACE PROCEDURE Balance_quantity_update(V_STORE_ID IN NUMBER,  V_ITEM_SERIAL IN NUMBER) IS
BEGIN
  UPDATE WH_T_ITEMS A
  SET BALANCE_QTY = ITEM_QTY
  WHERE STORE_ID = V_STORE_ID
  AND ITEM_SERIAL = V_ITEM_SERIAL
  AND ITEM_QTY = (SELECT MAX(ITEM_QTY)
                  FROM WH_T_ITEMS B
                  WHERE A.STORE_ID = B.STORE_ID
                  AND A.ITEM_SERIAL = B.ITEM_SERIAL);
END;i have got the follwing ora
ERROR at line 1:
ORA-00955: name is already used by an existing objecti tried 2 drop it but got another ora as follows
SQL> DROP PROCEDURE Balance_quantity_update;
DROP PROCEDURE Balance_quantity_update
ERROR at line 1:
ORA-04043: object BALANCE_QUANTITY_UPDATE does not existRegards,
Abdetu...