Hello everyone,

I don't get the meaning of

net.sf.hibernate.HibernateException: Batch update row count wrong: 0

I get this when specifying a jdbc.batch_size property value greater than 0. (for a value of 0, I get "net.sf.hibernate.HibernateException: SQL update or deletion failed (row not found)" instead)

This happens when I commit a transaction with two new objects (one parent, one dependant).

I'm using Hibernate 2.1.1, MySQL 3.23.58 and ConnectorJ 3.0.9.

Regards,

Andreas

Please show your mappings and the code you are executing

The data/object model is the User-UserRole relationship that is used by JDBCRealm of Tomcat 4.x:

One User can have multiple Roles, like "user" and "admin".

I have stripped the XDoclet-generated mapping descriptors down to what I think is essential:

<class
name="de.schildbach.user.business.User"
table="users"
dynamic-update="false"
dynamic-insert="false"
>

<id
name="name"
column="user_name"
type="string"
>
<generator class="assigned">
</generator>
</id>

<property
name="password"
type="string"
update="true"
insert="true"
column="user_pass"
/>

<set
name="userRoles"
lazy="false"
inverse="true"
cascade="all"
sort="unsorted"
>

<key
column="user_name"
/>

<one-to-many
class="de.schildbach.user.business.UserRole"
/>
</set>

</class>

<class
name="de.schildbach.user.business.UserRole"
table="user_roles"
dynamic-update="false"
dynamic-insert="false"
>

<id
name="id"
column="id"
type="integer"
>
<generator class="identity">
</generator>
</id>

<many-to-one
name="user"
class="de.schildbach.user.business.User"
cascade="none"
outer-join="auto"
update="true"
insert="true"
column="user_name"
not-null="true"
/>

<property
name="roleName"
type="string"
update="true"
insert="true"
column="role_name"
/>

</class>

Here is my code, adapted from manual chapters 9.2 and 9.3:

Session session = HibernateUtil.currentSession();
Transaction tx = null;

try
{
tx = session.beginTransaction();

if(session.find("FROM " + User.class.getName() + " u WHERE u.name = ?", userName, Hibernate.STRING).size() > 0)
throw new ActionException("error_user_exists");

UserRole role = new UserRole();
role.setRoleName("user");

User user = new User();
user.setName(userName);
user.setPassword(password);
// ...set other properties...
user.setUserRoles(new HashSet());
user.addUserRole(role);

session.save(user);

tx.commit(); // this is where the exception is thrown

}
catch(RuntimeException x)
{
if(tx != null) tx.rollback();
throw x;
}
finally
{
HibernateUtil.closeSession();
}

I forgot to post the addUserRole method in User:

public void addUserRole(UserRole role)
{
role.setUser(this);
userRoles.add(role);
}

All normal properties are straightforward, I'll post just the instance variables:

User:

private String name;
private String password;
private Set userRoles;

UserRole:

private int id;
private User user;
private String roleName;

Just a quick look ... missing an inverse=true for your many-to-one?

I've got the "inverse" on the side of the collection.

This is in accordance with the example in chapter 9.2.

Oh yes, sorry, didn't look properly ... let's see if I can find something else

Probably a driver issue, have you tried using the 3.1. MySQL Connector release for a test?

That reminds me that I am using relaxAutoCommit=true and MyISAM tables. Could this be a problem?

A simple replacement of

mysql-connector-java-3.0.9-stable-bin.jar

with

mysql-connector-java-3.1.0-alpha-bin.jar

does not help.

Even the removal of "relaxAutoCommit=true" in the JDBC URL does not prevent the exception.