Обсуждение: Transactional behaviour with trigger

Hi,

I create two records in a transaction in two different tables: customer
and contactaddress. customer has a foreign key to contactaddress.

I also have third table, customeraddress, which is a materialized view
of the join of customer and contactaddress

For the table customer I have a trigger(function) that inserts a record
in this third table (which works OK as the record is added):

....
INSERT INTO customeraddress(customer, customernumber, lastname, zipcode, city,housenumber, address) 
VALUES(NEW.objectid,NEW.customernumber,NEW.lastname,NULL,NULL,NULL,NULL);


For the contactaddress I also have a trigger(function) that should
update the record in the third table with the additional info of the
contactaddress:

....
SELECT INTO customer_record objectid FROM prototype.customers WHERE contactaddress = NEW.objectid;
IF customer_record.objectid IS NOT NULL THEN
UPDATE customeraddress set zipcode = NEW.zipcode, city = NEW.city, housenumber = NEW.housenumber , address =
NEW.objectid
 
WHERE customer = customer_record.objectid;

This last trigger is executed but customer_record.objectid seems to be
always NULL as if the the customer record is not visible. Is that
correct or is there something wrong with the SQl above?

In other words:

1. start transaction
2. add customer record
3. fire customer insert trigger -> copy record to materialized view table
4. add contactaddress record
5. fire contactaddress insert trigger -> update record in materialized view table -> no customer record???
6. end transction

TIA


-- 
Groeten,

Joost Kraaijeveld
Askesis B.V.
Molukkenstraat 14
6524NB Nijmegen
tel: 024-3888063 / 06-51855277
fax: 024-3608416
web: www.askesis.nl

On Sun, Sep 17, 2006 at 02:32:10PM +0200, Joost Kraaijeveld wrote:
> For the contactaddress I also have a trigger(function) that should
> update the record in the third table with the additional info of the
> contactaddress:
> 
> ....
> SELECT INTO customer_record objectid FROM prototype.customers WHERE contactaddress = NEW.objectid;
> IF customer_record.objectid IS NOT NULL THEN
> UPDATE customeraddress set zipcode = NEW.zipcode, city = NEW.city, housenumber = NEW.housenumber , address =
NEW.objectid
 
> WHERE customer = customer_record.objectid;
> 
> This last trigger is executed but customer_record.objectid seems to be
> always NULL as if the the customer record is not visible. Is that
> correct or is there something wrong with the SQl above?

Where does prototype.customers fit in?  Are you sure it has a row
that matches the WHERE clause?  Where would that row have come from?

Is there a reason you're maintaining customeraddress as a materialized
view rather than as a "real" view?

-- 
Michael Fuhr

Hi Michael,

Thanks for answering.


On Sun, 2006-09-17 at 08:36 -0600, Michael Fuhr wrote:
> On Sun, Sep 17, 2006 at 02:32:10PM +0200, Joost Kraaijeveld wrote:
> Where does prototype.customers fit in?  Are you sure it has a row
> that matches the WHERE clause?  Where would that row have come from?
I have solved it by rethinking what was actually happening and boosting
the traces of JBoss to see what it actually did. 

It actually did this:
1. start transaction
2. add customer record
3. add contactaddress record
4  update the customer record   <--- !!!!
5. end transction

So I moved the update of the materialized view to an update trigger of
the customer table and now it works.

> Is there a reason you're maintaining customeraddress as a materialized
> view rather than as a "real" view?
Pure performance reasons.


-- 
Groeten,

Joost Kraaijeveld
Askesis B.V.
Molukkenstraat 14
6524NB Nijmegen
tel: 024-3888063 / 06-51855277
fax: 024-3608416
web: www.askesis.nl