Thank you Alex, I have already received a possible solution from Marco Garbelini and I'll try it, but particularly, the one you are suggesting (my own key generator class) sounds interesting. How could I implement it in the EJB CMP architecture?
Marco ----- Original Message ----- From: "Alexey Loubyansky" <[EMAIL PROTECTED]> To: "Marco Tedone" <[EMAIL PROTECTED]> Sent: Thursday, June 26, 2003 7:12 AM Subject: Re: [JBoss-user] Question about CMP entity > Hello Marco, > > if the problem really is a primary key generation you could consider > entity-commands in JBoss-3.2. > The options are: > - database key generation (sequences, etc); > - custom sql; > - you can supply your own key generator class that will be asked for > the next key; > - JDBC3.0 PreparedStatement.getGeneratedKeys(). > > alex > > Thursday, June 26, 2003, 1:06:43 AM, Marco Tedone wrote: > > MT> Sorry guru for the [silly] question: I am having a discussion with people in > MT> my project regarding the container work with CMP entity beans. More > MT> specifically, we want to implement a Numerator table to assign numbers to > MT> several entities of our model. > > MT> Suppose a client wants to assign a value to a peopleId field in a People > MT> table, then it will in order: > > MT> 1) Access the Numerator table (behind a CMP entity bean) > MT> 2) Retrieve the value from the number field; > MT> 3) Assign that value to peopleId > MT> 4) Increment the value by 1 > > MT> What I am saying to the guys in the project is that the container (Jboss in > MT> our case) could ensure that, from the moment when the number is retrieved to > MT> the moment when the number is incremented by 1 nobody else will be able to > MT> alter the value of the number field in the Numerator table. Someone is > MT> replying that we should implement a synchronized method. Is that really > MT> necessary? I'm quite sure that there is a way to instruct the container to > MT> 'lock' in a certain sense the value of the number field. One way could be a > MT> transaction (shall we use synchronization in this case?); is there anything > MT> simplier? > > MT> Many thanks for your time, > > MT> Marco > > > > ------------------------------------------------------- > This SF.Net email is sponsored by: INetU > Attention Web Developers & Consultants: Become An INetU Hosting Partner. > Refer Dedicated Servers. We Manage Them. You Get 10% Monthly Commission! > INetU Dedicated Managed Hosting http://www.inetu.net/partner/index.php > _______________________________________________ > JBoss-user mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/jboss-user > ------------------------------------------------------- This SF.Net email is sponsored by: INetU Attention Web Developers & Consultants: Become An INetU Hosting Partner. Refer Dedicated Servers. We Manage Them. You Get 10% Monthly Commission! INetU Dedicated Managed Hosting http://www.inetu.net/partner/index.php _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user
