Web Dynpro using EJB to implement database access for MS SQL 2005 server

[Former Member]

Hello,

For using EJB model in Java Web Dynpro, why do I need another dictionary project with all the required tables (there are 5 tables in my project), when the same database is already created in back end MS SQL 2005 Server.

Thanks

Srinivas

[Former Member · Accepted solution]

Hi Srinivas,

If my understanding is correct, you want to access an EJB in your webdypro project where in your EJB is accessing 5 tables which are in MS SQL 2005 Server.

This can be achievable with out creating Dictionary project. Why you are trying to create dictionary project? Please explain your problem in detail.

Regards,

Jaya.

[Former Member · Accepted solution]

Thanks for your replies.

I was following this howtodo doc: https://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/1f5f3366-0401-0010-d6b0-e85a49e9...

Thanks for clearing my doubt.

I have created the required beans in the EJB module project. How to know , how many data access command beans I need in a separate Java project, so that I can call the session bean ?

The how to document I mentioned above is a simple case, where only one Data Access Command Bean is created.

[Former Member · Accepted solution]

Hi,

It depends on your business objects. For example if you have two ejbs ( session beans) like SalesOrdersEJB & ProductsEJB. Better to create seperate Data Access Comman beans for seperate session beans. As per my knowledge advantage of having seperate data access beans is if there is a change in first SalesOrdersEJB methods like input/ out put change , you need to modify only the corresponding data access bean. Other beans you need not to touch.

Regards,

Charan

[Former Member · Accepted solution]

Thanks for your reply Charan,

I am fairly new to EJB. I have created only one session bean (called TrainingBean) and created all the business methods inside it.

Here is my database schema, with the following 5 tables

Courses

CourseSchedules

Students

Registrations

Competencies

Here are the session bean business methods:

changeCourse(String)
changeStartDate(String)
createCourse()
createCourseSchedule()
getCourses()
getCourseSchedules()
registerStudent(String)
unRegisterStudent(String)

Is this good way to implement EJB, or should I create multiple session beans and multiple corresponding Data access command beans ?

Thanks a lot

Srinivas

[Former Member · Accepted solution]

Hi,

As per my knowledge dividing into multiple session beans is only for ease of use. You can devide into two session beans as StudentCourses and StudentRegistration. In future even if there is any change in registration process (input/output) ..you need not to touch the StudentCourses bean and corresponding data access bean.

Regards,

Charan

[Former Member · Accepted solution]

What about the entity beans Charan,

Here is the list of entity beans I created:

CourseBean
RegistrationBean
ScheduleBean
StudentBean

So, 2 session beans, StudentCourses and StudentRegistration, should be good in my case then?

If possible can you explain like a brief overview or importance of session bean, and how much functionality does a session bean should contain

Is it like web dynpro component, which contains discrete step in a business process ???

[Former Member]

Hi,

As per my knowledge, If tables are already present in the database, then there is no need of dictionary project. What is your actual issue? Are you able to access MS SQL 2005 server through EJB?

Regards,

Charan