I have class A and class B with the following mapping files:
(I use Hibernate 3.1 and HSQLDB 1.8.0)




So it's a simple unidirectional many-to-one association.
If I try to delete an object with type B, I get the following exception:

2006-10-01 23:11:00,196 [main] WARN org.hibernate.util.JDBCExceptionReporter -
SQL Error: 0, SQLState: null
2006-10-01 23:11:00,196 [main] ERROR org.hibernate.util.JDBCExceptionReporter -
failed batch
2006-10-01 23:11:00,236 [main] ERROR org.hibernate.event.def.AbstractFlushingEve
ntListener - Could not synchronize database state with session
org.hibernate.exception.GenericJDBCException: Could not execute JDBC batch update
at org.hibernate.exception.SQLStateConverter.handledNonSpecificException
(SQLStateConverter.java:103)
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.j
ava:91)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelp
er.java:43)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:
202)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:235)

at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:144)

at org.hibernate.event.def.AbstractFlushingEventListener.performExecutio
ns(AbstractFlushingEventListener.java:297)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlus
hEventListener.java:27)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:985)
at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:333)
at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java
:106)
at webshop.db.HibernateUtil.delete(Unknown Source)
at webshop.db.PersistentObject.delete(Unknown Source)
at test.consoleprograms.language.DeleteLanguage.main(Unknown Source)
Caused by: java.sql.BatchUpdateException: failed batch
at org.hsqldb.jdbc.jdbcStatement.executeBatch(Unknown Source)
at org.hsqldb.jdbc.jdbcPreparedStatement.executeBatch(Unknown Source)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.jav
a:58)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:
195)





In my application I would like to prevent such rows of the table B from deleting which are referenced by any rows of table A i. e. a parent row can not be deleted until it have any child rows. How can I achieve this, how can I get an appropriate exception e. g.? I think this exception above is not the right one.....

Thank you!

That exception seems to point to other problems. For example you may be trying to run database commands outside of a session/transaction?

For the second part of your question, one possible is to use foreign key constraints if the database supports them. For HSQLDB look under constraint definition in this page
http://www.hsqldb.org/doc/guide/ch09.ht ... le-section


Not sure if this helps ...

Marius

Thank you Marius!

I got the problem! The constraints work well, but hsql driver doesn't. The driver simple doesn't give any information about the problem that occured while it's trying to delete a parent row. I noticed that Hibernate want to execute the statement in batch and I found the place in the code of the hsql driver which raises the javax.sql.BatchUpdateException. The driver doesn't give any information, why the statement is failed.


I checked it via JDBC as well. A tried to delete a parent row by
PreparedStatement.executeBatch and I got the same. But if I use PreparedStatement.execute then i get the expected exception.

So the problem was caused by the hsql driver.....

by

Nice, thanks for sharing. So the exception was due to constraints being enforced or some other problem?

The exception was occured because of foreign key integrity violation, but the hsql driver simple said: failed batch update etc. So the exception was due to the constrainst.

Bye