Re: Can this be done with a trigger?
Date: Wed, 6 Aug 2008 07:46:55 -0700 (PDT)
Message-ID: <90227953-a494-4cf6-9825-5c3857b76127@8g2000hse.googlegroups.com>
On Aug 6, 9:18 am, "Shakespeare" <what..._at_xs4all.nl> wrote:
> <artme..._at_yahoo.com> schreef in berichtnews:d70b2a64-8d2c-49f4-b3d0-f1fa9389715a_at_56g2000hsm.googlegroups.com...
>
>
>
> > On Aug 6, 8:09 am, Aya the Vampire Slayer
> > <ry..._at_gatech.rmv.this.part.edu> wrote:
> >> artme..._at_yahoo.com wa:
>
> >> >On Aug 6, 3:23 am, "Shakespeare" <what..._at_xs4all.nl> wrote:
> >> >> Do you look for inserting and updating as well in your trigger (since
> >> >> you
> >> >> only posted part of your code)? Or else your triggers fires on an
> >> >> update and
> >> >> performs an insert.
>
> >> >The trigger fires on insert or update. The actual trigger code is
> >> >here. Do you see anything wrong with it?
> >> >CREATE OR REPLACE TRIGGER customer_config_trg
> >> > INSTEAD OF UPDATE OR INSERT ON customer_config_vw
> >> > FOR EACH ROW
> >> >BEGIN
> >> > IF INSERTING THEN
>
> >> You also need to write your INSERT dml for the main table here before
> >> inserting into the HIST table. An INSTEAD OF trigger doesn't do it
> >> automatically like BEFORE/AFTER triggers do.
>
> >> INSERT INTO CUSTOMER_CONFIG
> >> VALUES (...);
>
> >> > INSERT INTO customer_config_hist
> >> > VALUES
> >> >(:NEW.customer_id, :NEW.product_id, :NEW.format, :NEW.status,
> >> >:NEW.source,
> >> >SYSDATE);
> >> > END IF;
> >> > IF UPDATING THEN
>
> >> Same here, you also need to write the UPDATE dml for the main table here
> >> before inserting an entry into the HIST table.
>
> >> UPDATE CUSTOMER_CONFIG
> >> SET FOO = :new.FOO
> >> (...)
> >> where (...);
>
> >> > IF :NEW.format IS NOT NULL THEN
> >> > INSERT INTO customer_config_hist
> >> > VALUES
> >> >(:NEW.customer_id, :NEW.product_id, :NEW.format, :OLD.status,
> >> >:NEW.source,
> >> >SYSDATE);
> >> > ELSIF :NEW.status IS NOT NULL THEN
> >> > INSERT INTO customer_config_hist
> >> > VALUES
> >> >(:NEW.customer_id, :NEW.product_id, :OLD.format, :NEW.status,
> >> >:NEW.source,
> >> >SYSDATE);
> >> > END IF;
> >> > END IF;
> >> >END;
> >> >/
>
> >> --
> >> "Care must be exorcised when handring Opiticar System as it is apts to
> >> be sticked by dusts and hand-fat." --Japanese Translators
>
> >> "Keep your fingers off the lens." --Elton Byington, English Translator
>
> > This is VERY interesting. If you look above at my table definitions,
> > the last column, SOURCE, is not in the original table that the view is
> > based on, but is created as a column because it is needed in the
> > second view.
>
> > If I perform an insert using a NULL for the value of that column, as
> > below, it works fine. But, if I put a value in for that column, it
> > aborts:
>
> > SQL> desc customer_config_vw
> > Name Null? Type
> > ----------------------------------------- --------
> > ----------------------------
> > CUSTOMER_ID NUMBER
> > PRODUCT_ID VARCHAR2(10)
> > FORMAT VARCHAR2(4)
> > STATUS VARCHAR2(15)
> > DATE_ADDED DATE
> > DATE_MODIFIED DATE
> > SOURCE VARCHAR2
>
> > insert into customer_config_vw
> > values (1234,'PFP','Text','Active',SYSDATE,SYSDATE,NULL);
>
> > 1 row created.
>
> > insert into customer_config_vw
> > values (67890,'PPM','HTML','Unsubscribe',SYSDATE,SYSDATE,'A');
> > insert into customer_config_vw
> > *
> > ERROR at line 1:
> > ORA-03113: end-of-file on communication channel
>
> > Any thoughts on this???
>
> Somehow something IS wrong here (I can't put my finger on it right now, but
> let's try):
> when you create the view, you define a default value for the SOURCE column.
> Then you perform an update on the view. Though the SOURCE column get's
> updated, it is not possible to retrieve its value, because of the fixed
> value in the view definition. As long as NEW.SOURCE is the same value as the
> default, there's no conflict. But when you update it with a new value, there
> is a conflict. I think your default is still NULL, right?
> You could try to replace your view definition with e.g. 'X' as a default
> value for SOURCE, and then test what happens
> a) when you update it to 'X'
> b) when you update it to 'A'.
> (It might work better because with a default of 'X' at least the type and
> length of the original and new column match). I have no opportunity to test
> it right now...
>
> Furthermore, you do not write your other values (other than SOURCE) to the
> original table, due to the INSTEAD OFF trigger. As Aya stated, no values
> will be written to the table ever.
>
> Shakespeare
I changed the trigger. But I know it has something to do with adding that last column........see below. I also tried your suggestion with the column, see below. All I want is to create a view that containsthe columns from the first table, along with one column in the second table. Then use the INSTEAD OF trigger to update both tables within the body of the trigger.......I'm sure that can be done.
CREATE OR REPLACE VIEW CUSTOMER_CONFIG_VW
(CUSTOMER_ID, PRODUCT_ID, FORMAT, STATUS, DATE_ADDED,
DATE_MODIFIED, SOURCE)
AS
SELECT CUSTOMER_ID,PRODUCT_ID,FORMAT,STATUS,DATE_ADDED,DATE_MODIFIED,
'X' source
FROM customer_config
/
SQL> insert into CUSTOMER_CONFIG_VW (source) values ('X');
*ERROR at line 1:
ORA-01733: virtual column not allowed here
CREATE OR REPLACE TRIGGER customer_config_trg
INSTEAD OF UPDATE OR INSERT ON customer_email_config_vw
FOR EACH ROW
BEGIN
IF INSERTING THEN
INSERT INTO customer_config VALUES
(:NEW.customer_id, :NEW.product_id, :NEW.format, :NEW.status, :NEW.source, SYSDATE);
INSERT INTO customer_config_hist VALUES
(:NEW.customer_id, :NEW.product_id, :NEW.format, :NEW.status, :NEW.source, SYSDATE);
END IF; IF UPDATING THEN
IF :NEW.format IS NOT NULL THEN UPDATE customer_config SET format = :NEW.format WHERE customer_id = :NEW.customer_id AND product_id= :NEW.product_id;
INSERT INTO customer_config_hist VALUES
(:NEW.customer_id, :NEW.product_id, :NEW.format, :OLD.status, :NEW.source, SYSDATE);
ELSIF :NEW.status IS NOT NULL THEN UPDATE customer_config SET status = :NEW.status WHERE customer_id = :NEW.customer_id AND product_id= :NEW.product_id;
INSERT INTO customer_config_hist VALUES
(:NEW.customer_id, :NEW.product_id, :OLD.format, :NEW.status, :NEW.source, SYSDATE);
END IF;
END IF;
END;
/ Received on Wed Aug 06 2008 - 09:46:55 CDT