I've been working with using pessimistic locking in Derby, and I've observed that it doesn't apply the correct SELECT...FOR UPDATE syntax according to the Derby reference documents[1]. As a result, I'm getting StaleStateExceptions whenever multiple transactions attempt to modify the same row. I've identified that the DerbyDialect of the current codebase[2] doesn't override the getForUpdateString method, which means that it uses the one in the DB2Dialect[3]. Unfortunately, this method doesn't have the correct Derby syntax.

[1] http://db.apache.org/derby/docs/10.2/re ... 31783.html
[2] http://anonsvn.jboss.org/repos/hibernat ... alect.java
[3] http://anonsvn.jboss.org/repos/hibernat ... alect.java

Hibernate version: 3.2.4.sp1
Name and version of the database you are using: Derby v10.2.2.0

Code between sessionFactory.openSession() and session.close():


The generated SQL (show_sql=true):


According to the Derby docs, this last bit should just be "for update". Could someone verify that I'm not missing something, and let me know whether this should be filed in JIRA?

Thanks!
Andrew Miner

Could anyone from the Hibernate team confirm that this should be filed with JIRA?

Thanks!

Hi,

I'm not from the Hibernate team but I can confirm I was having the same problem.

A workaround is just to subclass DerbyDialect and override getForUpdateString as in:

public class DerbyDialect extends org.hibernate.dialect.DerbyDialect {

/**
* Uses "for update" rather than "for read only" as per Derby docs
*
* @see org.hibernate.dialect.DB2Dialect#getForUpdateString()
*/
@Override
public String getForUpdateString() {
return " for update with rs";
}
}