hi , i am trying to insert a record into mysql database through a simple javaprogramming using hiber nate ? I am able to insert 1 record , but i am trying to enter a second record i am getting the following error ???????


log4j:WARN No appenders could be found for logger (org.hibernate.cfg.Environment).
log4j:WARN Please initialize the log4j system properly.
Inserting Record
Done
Hibernate: insert into CONTACT (FIRSTNAME, LASTNAME, EMAIL, ID) values (?, ?, ?, ?)
org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
at org.hibernate.exception.ErrorCodeConverter.convert(ErrorCodeConverter.java:74)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:161)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:226)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:136)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:274)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:27)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:669)
at roseindia.tutorial.hibernate.FirstExample.main(FirstExample.java:36)
Caused by: java.sql.BatchUpdateException: Duplicate key or integrity constraint violation message from server: "Duplicate entry '3' for key 1"
at com.mysql.jdbc.PreparedStatement.executeBatch(PreparedStatement.java:1492)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:57)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:154)
... 6 more
Exception in thread "main"



here is my main java class code :::


package roseindia.tutorial.hibernate;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;


/**
* @author Deepak Kumar
*
* http://www.roseindia.net
* Hibernate example to inset data into Contact table
*/
public class FirstExample {
public static void main(String[] args) {
Session session = null;

try{
// This step will read hibernate.cfg.xml and prepare hibernate for use
SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();
session =sessionFactory.openSession();
//Create new instance of Contact and set values in it by reading them from form object
System.out.println("Inserting Record");
Contact contact = new Contact();
contact.setId(3);
contact.setFirstName("Deepak");
contact.setLastName("Kumar");
contact.setEmail("deepak_38@yahoo.com");
session.save(contact);
System.out.println("Done");
}catch(Exception e){
System.out.println(e.getMessage());
}finally{
// Actual contact insertion will happen at this step
session.flush();
session.close();

}

}
}

The problem is when you run de code for de second time and a key violation occurs. Each time that you run your code, you have change the line:

contact.setId(3);

to

contact.setId(4); // Second time you run the code

to

contact.setId(5); // Third time you run the code

and so on.

Reinaldo.

Actually, don't set the id in the Object when you are inserting. You should set an id generator in your mapping file and then that will automatically generate an id for you (I recommend Sequence if you are just going in numerical order).

Are you trying to insert the same record twice? If you have a primary key constraint then that is why you are getting the error (as you cannot have duplicate primary keys).

Hope this helps,
-B

also check out your mapping file, looking for the <id ...unsaved-value="null">.

perhaps you want hibernate to generate the key and as such you wouldn't have to specify the # for id.

example:
<id name="id" unsaved-value="null">
<generator class="hilo">
<param name="table">my_seq_table</param>
<param name="column">current_value</param>
</generator>
</id>

create a table named my_seq_table(current_value number);
and seed it with a 1, and then everytime you do a save hibernate will generate an ID for you. (and you should not explicitly set with the setId())...

If this helped please give out the credits... thx. I need 'em.

oops, I hit the refresh button... :p

setty_4u -- did any of this help?

If so, please provide the credit for the answer...to the folks that helped.
(as you review the postings for this question there is a Y/N prompt after each to prompt you to post credit to the person who helped.)