1 Reply Latest reply on Apr 2, 2007 6:12 PM by fhh

Question about sequences and entity ejbs 3.0

balteo Apr 2, 2007 8:41 AM

Hello,

I have simplified my problem as follows: I have a three-field table as follows:

pk key name
1 1 johm (this is an insert)
2 1 john (this is an update)
3 2 Pat (this is an insert)

The requirement for one table cannot be changed.

I have a auto generated identity or a sequence for pk.

My question relates to key. As you have noticed key is not unique.

How can I retrieve the value used for the pk for use by key field when I do an insert bearing in mind I currently use an auto generated identity (with DB2). Do I need a sequence? Please advise me on the best strategy.

Please tell me what code I need on the entity bean side (the one that is persisted) and on the session bean side (the one that persists the entity).

Please help!!!

Thanks in advance,

Julien Martin.

1. Re: Question about sequences and entity ejbs 3.0

fhh Apr 2, 2007 6:12 PM (in response to balteo)

Well on my database primary keys are usually not changed by an update. So your example would look like this:

pk key name
1 1 johm (this is an insert)
1 1 john (this is an update)
2 2 Pat (this is an insert)

If you want a column that increments on updates look at the @version annotation or use a trigger.

Regards

Felix
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