Hibernate version: 2.1.6
Name and version of the database you are using: Oracle 9i

I have an object with a composite-id and I have the composite-id as a seperate class. I can load the instance by giving whole composite-id attributes but I want to retrieve the row with a maximum of one of the key columns.

Example: (from Hibernate references)

User class has a field UserID class which has two fields (userName, organizationUnit) and these are composite-id in the User.xml like this.
<class name="User" table="USER">
<composite-id name="userId" class="UserId">
<key-property name="userName" column="USERNAME"/>
<key-property name="organizationId" column="ORGANIZATION_ID"/>
</composite-id>
<property ...
...
</class>

The UserID class looks like :

public class UserId extends Serializable
{
private String username;
private String organizationId;

public UserId(String username, String organizationId)
{
this.username = username;
this.organizationId = organizationId;
}

// Getters...

public boolean equals(Object o) {....}
public int hashCode() {....}
}

I can load an instance with the code:

UserId id = new UserId("john", 42);
User user = (User) session.load(User.class, id);

but I want to query something like this: (here is the question)

max(organizationId) from User where userName like "john"

I know sample is nonsense but my problem is something like that.

Note: I searched the FAQ, I hope I didn't miss a post like that...

I hate finding the answer after posting a message but after trying all the possibilities I found the solution.

Query q = hSession.createQuery("select max(u.userId.organizationId) from User u where u.userId.userName = :pName")

this worked for me....