Re: OJB 1.0.4 and ODMG Database.makePersistent
Hi Dirk, Kessler, Dirk wrote: Armin, thanks for your reply. We have transactions that span multiple web requests (pages) and we use the PK values to identify objects that have been persisted on the various pages (in order to re-display the contents of the objects if the user goes back to one of those pages). There are definitely many other ways we could have solved this problem but re-using the IDs created by the makePersist method seemed the most straightforward (since OJB makes sure that all of the IDs are unique). I would suggest to use one of the OJB listener interface to get notified about the new inserted objects: http://db.apache.org/ojb/docu/guides/pb-guide.html#Hook+into+OJB+-+PB-Listener+and+Instance+Callbacks http://db.apache.org/ojb/docu/guides/odmg-guide.html#Access+the+PB-api+within+ODMG e.g. your class can implement PBLifeCycleListener and add itself (if objects will be inserted) after the odmg-tx started as temporary listener, then on t.commit you can read all PK's via PBLifeCycleListener#afterInsert Instead of the PK values you can use the OJB Identity object of each persistent object, then you can re-display the objects via PersistenceBroker#getObjectByIdeneity which is much faster than using an OQL-query. regards, Armin Thanks for your suggestion of using the SequenceManager. -Dirk -Original Message- From: Armin Waibel [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 10, 2006 7:02 AM To: OJB Users List Subject: Re: OJB 1.0.4 and ODMG Database.makePersistent Hi Dirk, Kessler, Dirk wrote: There appears to be a change in behavior in the Database.makePersistent method. In OJB 1.0RC7 the Database.makePersistent class would update the primary key field of the object being persisted (autoincrement) even before the transaction was committed (I.E. right after the makePersistent call). It appears that in OJB 1.0.4 the primary key value does not get updated until the transaction is committed. yep, this change was needed to harmonize OJB behavior with SequenceManager based on database identity columns. In this case it's not possible to set the PK values when the object is stored (#makePersistent call), only after the object is written to DB. Only this way OJB will show the same behavior for all DB/PK-generation. Is there any way to have makePersistent set the primary key value (it can't be a transient value, it has to be the balue eventually stored in the database)? It would be easy to implement a method which lookup the SequenceManager obtain the next PK value and set this value in your object - but this will cause some overhead. Why do you need the "PK assign before store" functionality? regards, Armin - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: OJB 1.0.4 and ODMG Database.makePersistent
Armin, thanks for your reply. We have transactions that span multiple web requests (pages) and we use the PK values to identify objects that have been persisted on the various pages (in order to re-display the contents of the objects if the user goes back to one of those pages). There are definitely many other ways we could have solved this problem but re-using the IDs created by the makePersist method seemed the most straightforward (since OJB makes sure that all of the IDs are unique). Thanks for your suggestion of using the SequenceManager. -Dirk -Original Message- From: Armin Waibel [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 10, 2006 7:02 AM To: OJB Users List Subject: Re: OJB 1.0.4 and ODMG Database.makePersistent Hi Dirk, Kessler, Dirk wrote: > There appears to be a change in behavior in the Database.makePersistent > method. In OJB 1.0RC7 the Database.makePersistent class would update the > primary key field of the object being persisted (autoincrement) even > before the transaction was committed (I.E. right after the > makePersistent call). It appears that in OJB 1.0.4 the primary key value > does not get updated until the transaction is committed. > yep, this change was needed to harmonize OJB behavior with SequenceManager based on database identity columns. In this case it's not possible to set the PK values when the object is stored (#makePersistent call), only after the object is written to DB. Only this way OJB will show the same behavior for all DB/PK-generation. > > > Is there any way to have makePersistent set the primary key value (it > can't be a transient value, it has to be the balue eventually stored in > the database)? > It would be easy to implement a method which lookup the SequenceManager obtain the next PK value and set this value in your object - but this will cause some overhead. Why do you need the "PK assign before store" functionality? regards, Armin - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: OJB 1.0.4 and ODMG Database.makePersistent
Hi Dirk, Kessler, Dirk wrote: There appears to be a change in behavior in the Database.makePersistent method. In OJB 1.0RC7 the Database.makePersistent class would update the primary key field of the object being persisted (autoincrement) even before the transaction was committed (I.E. right after the makePersistent call). It appears that in OJB 1.0.4 the primary key value does not get updated until the transaction is committed. yep, this change was needed to harmonize OJB behavior with SequenceManager based on database identity columns. In this case it's not possible to set the PK values when the object is stored (#makePersistent call), only after the object is written to DB. Only this way OJB will show the same behavior for all DB/PK-generation. Is there any way to have makePersistent set the primary key value (it can't be a transient value, it has to be the balue eventually stored in the database)? It would be easy to implement a method which lookup the SequenceManager obtain the next PK value and set this value in your object - but this will cause some overhead. Why do you need the "PK assign before store" functionality? regards, Armin - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
OJB 1.0.4 and ODMG Database.makePersistent
There appears to be a change in behavior in the Database.makePersistent method. In OJB 1.0RC7 the Database.makePersistent class would update the primary key field of the object being persisted (autoincrement) even before the transaction was committed (I.E. right after the makePersistent call). It appears that in OJB 1.0.4 the primary key value does not get updated until the transaction is committed. Is there any way to have makePersistent set the primary key value (it can't be a transient value, it has to be the balue eventually stored in the database)? Thanks in advance, -Dirk
