EJB/JPA Session/Entity Bean: Back Reference Id not set

[Former Member]

Hello All,

I m using JPA as a persist tool. I have an entity Account and in Account there is a collection of entity AccountDetail. In Account entity relation for AccountDetail is One-To-Many and in AccountDetail the relation for Account is Many-To-One. When i save the Account, object of Account and AccountDetail are saved correctly. But the problem is that in AccountDetail the Id of Account is not saved in Database table. I have AccountId in AccountDetail table. plz help me??

Second thing is that how to generate automatically primary keys when entity saved in database ???

[former_member185086 · Accepted solution]

Hi

Its a more technical and from other forum better to take help from [this|http://www.sdn.sap.com/irj/scn/index?rid=/library/uuid/502f70a8-33a4-2b10-3dbe-bdcb5e25c6da&overridelayout=true]

Best Regards

Satish Kumar

[Former Member · Accepted solution]

Dear Satish,

thks for reply, the doc u referred to me containing simple example. I want an Entity that hold the Collection of another Entities.

[Former Member]

thks all

[Former Member]

>

> Second thing is that how to generate automatically primary keys when entity saved in database ???

Hello kapitsu,

what database are you using?

[Former Member]

Database: SqlServer2008.

JPA, Session/Entity Beans

[Former Member]

define the column you want to auto increment as an Integer with Identity attribute set to True (using the sql server management tool for example) and then put

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)

in front of the ID declaration in the mapping file, it should generate the IDs automatically.