so, add that procedure into you trigger after insert,after delete.. wherever
execute procedure recalculate_sums(new/old.pro_id);
where SP body something like

update stocks set amount =

(
SELECT sum(Quantity) On_Hand
FROM StockControl
WHERE Pro_Id = :Pro_Id
)
where
Pro_Id = :Pro_Id


ps. just make sure about transactions, if two users in same time with
same pro_id will work, I think you'll have to make transactions lock
wait to update correctly.

Fabio Gomes wrote:

>Just another question,
>
>How can i make a function to update the actual_stock after i delete a row?
>
>This works when i insert a row:
>
>CREATE TRIGGER SCI ACTIVE AFTER INSERT AS
>BEGIN
>UPDATE STOCK
>SET ACTUAL_STOCK = ACTUAL_STOCK + NEW.STOCK_ADDED
>WHERE PRO_ID = NEW.PRO_ID;
>END
>
>I want to make something like it:
>
>SELECT Pro_Id, sum(Quantity) On_Hand
>FROM StockControl
>WHERE Pro_Id = :Pro_Id
>
>I think that i need to make a function that actived after i delete
>something, than it sum all the stock for that product and write it on the
>actual_stock on the other table.
>
>is there some way to do it?
>
>Thanks guys :)
>
>
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