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Creating Entity bean for a 'table' without PrimaryKey

Hi,

I have a relation table without primarykey. My table name is "favorite" and it has:
worker_id int (FK to "worker" table)
task_id int (FK to "tasks" table)
priority int

If i want to create an Entity Bean, we usually create all the 'columns' with getter and setter along with the column type. For example, (just an example):

/**
       * @author bj 17.09.2004
       * Name
       *
       * @ejb.interface-method view-type = "both"
       * @ejb.persistence column-name = "name"
       * @return
       */
      public abstract String getName();

      /**
       * @ejb.interface-method view-type = "both"
       * @param name
       */
      public abstract void setName(String name);

The method ejbCreate() should have the return type of PrimaryKey. My every other table has a PK field and i do like:
public Integer ejbCreate() throws CreateException {
            return null;
}

Since my "Favorite" table doesn't have a PK field, how can i create en Entity bean for that table? How to solve the problem of ejbCreate() return type?

TimYates

It does have a primary key. The primary key is a composite of:

worker_id and task_id

isn't it?

Have a look at this: http://java.sun.com/j2ee/tutorial/1_3-fcs/doc/CMP8.html (for CMP) and this http://java.sun.com/j2ee/1.4/docs/tutorial/doc/BMP4.html (for BMP)

ldbkutty

ASKER

I understand that PK is combination of worker_id and task_id, but i cannot/shouldn't create the FK fields(getter, setter) in my Entity Bean. Instead I have to make the relation for those FK's.

For example, in my "Tasks" table, i have 'taskworker_id' FK column to "TaskWorker" table. In my Entity bean, i have:

/**
       * @author bj 16.09.2004
       *
       * Task TaskWorker Relation
       *
       * @ejb.interface-method
       *       view-type = "local"
       *
       * @ejb.relation
       *       name = "taskworker_task"
       * role-name = "task from taskworker"
       *
       * @jboss.relation
       *       fk-column = "'taskworker_id"
       *       related-pk-field = "id"
       *       fk-constraint = "true"
       */
      public abstract TaskWorkerLocal getTaskWorker();

      /**
       * @ejb.interface-method view-type = "local"
       * @param taskWorker
       */
      public abstract void setTaskWorker(TaskWorkerLocal taskWorker);

ASKER CERTIFIED SOLUTION

TimYates

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TimYates

> public FavouritePK ejbCreate( Worker w, Task t )

should be

public FavouritePK ejbCreate( Worker w, Task t, int priority )

ldbkutty

ASKER

sorry for late...but that worked great.

Thanks.

TimYates

:-) Cool :-)

Good luck with it :-)

Tim