-----Original Message----- From: Alex Loubyansky [mailto:[EMAIL PROTECTED] Sent: Friday, March 14, 2003 8:25 PM To: Chad Brandon Subject: Re[4]: [JBoss-user] CMP Entity Bean Insert/Commit after ejbPostCreate()
Thursday, March 13, 2003, 9:47:38 PM, you wrote: CB> Hi Alex, CB> I'd really like to know how to do this. First, if foreign key fields and primary key fields to the same columns in the database. Suppose, you create a Child entity when related Parent doesn't exist yet. Child is created and getParent() returns null (as there is no Parent yet) Later you create Parent for the created above Child. Relationship between Parent and Child is establisged automatically after ejbCreate and before ejbPostCreate (so in ejbPostCreate it is ready). Relationship is established only if Parent's pk columns have the same values as Child's primary key columns to which Parent's foreign key fields are mapped. Established relationship is destroyed only when Child or Parent is deleted. Attempts to change relationships with CMR setters results in exceptions as it is not allowed to change entity's primary key. It is also possible to have foreign key fields partly mapped to primary key columns and partly to its own columns. In this case you can manipulate relationships with CMR setters only if the don't affect primary key columns. Foreign key field is considered NULL if at least one column that is not a primary key one contains NULL value. It could be still hard to grasp. If you have a real problem then describe it and we'll follow a real example. alex CB> Thanks, CB> Chad CB> Alex Loubyansky <[EMAIL PROTECTED]> wrote:DS> 3.2 supports not null foreign keys, but you will have to ask Alexey how DS>> to set it up. CB> Just map foreign key fields to primary key columns. CB> This case is not trivial and we had hot debates on this topic with CB> Dain and Jeremy. If foreign key fields mapped to primary key fields is CB> what you need then feel free to ask for details on how it works. CB> Just FYI, you can also have a partial mapping, i.e. some of the foreign key CB> fields are mapped to primary key columns and others to its own. But CB> those that mapped to its own can't be NON NULL. CB> alex DS>> -dain DS>> On Thursday, March 13, 2003, at 10:42 AM, Jonathan.O'[EMAIL PROTECTED] DS>> wrote: >>> >>> Bernhard, >>> No, JBoss 3.x does the insert after ejbCreate. 4.0 is reputed to have >>> (will have) support for INSERT after ejbPostCreate. >>> >>> Ciao, >>> Jonathan O'Connor >>> Development Manager >>> XCOM Dublin >>> Phone: +353 1 872 3305 >>> Mobile: +353 86 824 0736 >>> >>> DS>> >>> >>> >>> >>> >>> Hi, >>> >>> does JBoss 3.2 issue INSERT/COMMIT after ejbPostCreate() or is it >>> possible >>> to configure it this way (you can do this e.g. in WebLogic) ? >>> >>> As far as I know, all JBoss 3.0.x versions already do an INSERT between >>> ejbCreate() and ejbPostCreate(). Has this changed in any newer >>> version()? >>> This is a problem for me, since this means FK columns can't be >>> declared as >>> NOT NULL since as y'all know CMR fields can only be set in >>> ejbPostCreate(). >>> I don't want to use Deferred Constraints feature some databases offer. >>> >>> >>> Cheers, >>> Bernhard >>> >>> >>> Bernhard Meyer-Willner, MSc >>> Insurance - Financial Services >>> _________________________________________ >>> >>> LogicaCMG >>> Logica GmbH >>> Osterbekstrasse 90b - Alster City >>> 22083 Hamburg >>> Germany >>> T: +49 (0) 40 27071-405 (direct) >>> M: +49 (0) 177 425-9036 >>> E: mailto:[EMAIL PROTECTED] >>> www.logicacmg.com ------------------------------------------------------- This SF.net email is sponsored by:Crypto Challenge is now open! Get cracking and register here for some mind boggling fun and the chance of winning an Apple iPod: http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0031en _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user ------------------------------------------------------- This SF.net email is sponsored by:Crypto Challenge is now open! Get cracking and register here for some mind boggling fun and the chance of winning an Apple iPod: http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0031en _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user
