Hi all,

I have an application which has a jsp front end and ejb as middle tier (SLSB) and Mule as ESB and hibernate as the ORM layer.
Now when the user starts to do a search, we give him a popup saying that the search has started.
There is a cancel button in this window.
If the use cancels his operation is there a way for me to cancel the query which is running in the DB and inform hibernate about this so that I can inform the user also.

Here are my parameters to my hibernate file
<property name="hibernate.jndi.class">weblogic.jndi.WLInitialContextFactory</property>
<property name="connection.datasource">jdbc/epcGmnaDataSource</property>
<property name="dialect">org.hibernate.dialect.OracleDialect</property>
<property name="transaction.factory_class">org.hibernate.transaction.JTATransactionFactory</property>
<property name="jta.UserTransaction">javax.transaction.UserTransaction</property>
<property name="hibernate.transaction.manager_lookup_class">org.hibernate.transaction.WeblogicTransactionManagerLookup</property>
<property name="current_session_context_class">jta</property>
<property name="show_sql">false</property>
<property name="hibernate.cglib.use_reflection_optimizer">false</property>
<property name="hibernate.cache.use_query_cache">true</property>
<property name="hibernate.cache.use_minimal_gets">true</property>
<property name="hibernate.cache.provider_class">org.hibernate.cache.EhCacheProvider</property>
<property name="hibernate.cache.provider_configuration_file_resource_path">/ehcache.xml</property>
<property name="hibernate.cache.use_second_level_cache">true</property>

There are lots of applications that implement cancel by letting the UI continue while letting the backend proceed to a safe stopping point. There are ways to kill a connection, for example for mysql the following
http://dev.mysql.com/doc/refman/5.0/en/kill.html

I do not think it is a good idea to use this as a regular way to stop connections. Maybe you can design your application to:
1. use faster queries
2. use pagination or limit on the number of returned rows to complete faster
3. run the queries in a different thread, asynchronously and query from the browser in successive request

I hope this helps :)

Marius