Could this be a common enough issue that Hibernate includes a work-around type so that everyone doesn't have to write their own?
We've had to address this wonderful Oracle "feature" via a custom user type as well, ours is based on http://usertype.sourceforge.net/ and the NullSafeStringType and NullSafeStringColumnMapper are available here: https://github.com/Jasig/uPortal/blob/master/uportal-war/src/main/java/org/jasig/portal/dao/usertype/ Our approach is that any non-null string gets prefixed with _ when stored in the DB -Eric On 04/23/2012 01:23 PM, Steve Ebersole wrote: > Personally I think people relying on this Oracle (mis-)behavior are > just asking for problems. > > But lets say people do agree that we should handle this... so you add a > method to Dialect to handle detect this environment... how do you plan > on checking it? Today it is the Types that are responsible for > equality checking (I assume that is what Envers uses as well). So I am > just suggesting that the user supplying a custom > FunkyOracleStringVarcharType Type implementation is probably a better > option. Unless I misunderstand how Envers is doing the equality > checking and y'all do not use Types for that. > > On Mon 23 Apr 2012 11:18:44 AM CDT, Łukasz Antoniak wrote: >> Totaly agree that expecting null to be equal to empty string in Java model >> is wrong. >> >> IMO he has spotted that when null string reference is replaced with an empty >> string, Envers creates new revision. From database >> perspective (Oracle) two records does not differ in any way. This could be >> actually handled easily in Envers code. I thought that >> it would be more elegant to add new dialect feature, but if this behavior is >> special to Oracle, there is no need. >> >> // Revision 1 >> em.getTransaction().begin(); >> StrTestEntity emptyEntity = new StrTestEntity(""); >> em.persist(emptyEntity); >> em.getTransaction().commit(); >> // Should not generate revision after NULL to "" modification on Oracle. But >> now it does. >> em.getTransaction().begin(); >> emptyEntity = em.find(StrTestEntity.class, emptyId); >> emptyEntity.setStr(null); >> em.merge(emptyEntity); >> em.getTransaction().commit(); >> >> Will use dev mailing list. Sorry for that. >> >> Steve Ebersole wrote: >> > Their better option is to apply a Type for String that handles this. >> > >> http://docs.jboss.org/hibernate/orm/4.1/manual/en-US/html_single/#types-registry >> > >> > This is the type of thing we will be able to handle automatically in >> 5.0 >> > >> > But as for the forum user's exact question, personally I think him >> > expecting null and empty string *in the java model* to be handled >> > equally is just plain wrong. >> > >> > P.S., these kinds of questions should be directed at the dev list so >> we >> > can get everyone's input. >> _______________________________________________ >> hibernate-dev mailing list >> hibernate-dev@lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/hibernate-dev > -- > st...@hibernate.org > http://hibernate.org > _______________________________________________ > hibernate-dev mailing list > hibernate-dev@lists.jboss.org > https://lists.jboss.org/mailman/listinfo/hibernate-dev _______________________________________________ hibernate-dev mailing list hibernate-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev
