Re: Can this be done with a trigger?

On Aug 5, 11:43 am, gazzag <gar..._at_jamms.org> wrote:
> On 5 Aug, 17:11, artme..._at_yahoo.com wrote:
>
>
>
> > Hi,
>
> > We have a table like this:
>
> > CUSTOMER_ID
> > PRODUCT_ID
> > FORMAT
> > STATUS
> > DATE_ADDED
> > DATE_MODIFIED
>
> > We also have a history table like this:
>
> > CUSTOMER_ID
> > PRODUCT_ID
> > FORMAT
> > STATUS
> > SOURCE
> > DATE_ADDED
>
> > We want to put a trigger on the first table such that when a record is
> > inserted or updated it will make the entry to the history table.
> > However, the problem is the 'SOURCE' column on the history table. It
> > is not present or needed in the first table.
>
> > Entries into the first table are done through a PL/SQL program. So,
> > what we want is that when the entry is made into the first table, it
> > fires the trigger to make the second entry. But, how can this be done
> > if the columns do not match?
>
> > We do not want to code it in the PL/SQL program because then someone
> > can make an entry to the first table and we cannot record the history
> > on it, yet the SOURCE column only gets populated in the PL/SQL
> > program....
>
> > And, to make things more complicated, depending on what is being
> > UPDATED, we may need the values of :NEW or :OLD........
>
> > Is there a way to do this?
>
> Sure there is. What is SOURCE though?

Gazzag,

I am trying to write the trigger. Problem is since you cannot pass parameters to triggers, where does the trigger get the value for SOURCE? All I can think of is to update the record from the PL/SQL procedure once the trigger gets done........

So, say I have a procedure like this:

PROCEDURE ADD (

  p_customer_id  NUMBER,
  p_product_id   VARCHAR2,
  p_source       VARCHAR2 DEFAULT 'U') IS

  INSERT INTO customer_config
  VALUES (p_customer_id, p_product_id, 'Text', 'Active', SYSDATE);

The SOURCE is not needed in this table. But, this would fire the trigger where SOURCE is needed. The SOURCE will be derived within the PL/SQL code. I do not think this is possible. I may have to let the trigger fire, then go back and update the row..... Received on Tue Aug 05 2008 - 11:48:26 CDT