Hi All,

I have a table (USERROLE) with one primary key(UserRoleID) and two foreign keys (UserId and RoleID). I want to declare the two foreign keys together as composite unique key means, there will not be more than one row with same UserID, RoleID together.

Any one can give me some idea how this can be done by annotation ?

Thanks in Advance
Vasna

Any idea please....?

Vasna,
I hope below post can help you in resolving the issue.

http://www.mkyong.com/hibernate/hiberna ... p-example/

--Velu

Sorry Velu that is not by requirement, here the third table is a link table. My case is entirely different.

I have USER, ROLE, and QUOTA tables, In side the QUOTA I have UserID and RoleID as foreign key and QuotaID as primary key. I want to allow only one record for each UserID and RoleID together. For this I want to define UserID and RoleID together as unique key. So it will not allow to insert quota to same UserId and RoleID.

Any valuable suggestions please...

Any eye opening suggestions please....

Try with the @UniqueConstraint annotation as described in the documentation:

http://docs.jboss.org/hibernate/stable/ ... ing-entity

Hi nordborg,

Thanks for your reply. I have tried this in my class as follows
@UniqueConstraint(columnNames = { "QuotaID" }),
@UniqueConstraint(columnNames = { "RoleID", "UserID" })

But still I am able to insert multiple records with same RoleID and UserID combination.

Are you using Hibernate to generate the database schema? Why do you have a @UniqueConstraint on the QuotaID? It should not be needed if it is the primary key.

I am not using Hibernate to generate Schema, but I want to set the Composite Unique Constraint from Hibernate itself. Because there may be some DB that may not support some specific properties that is the reason I want to move all such thing to Class.

Even after removing the PK from the constrain it is working as the same.
Now I have the Constraint is as follows
@UniqueConstraint(columnNames = { "RoleID", "UserID" })

The @UniqueConstraint (and other similar annotations) are only used by the schema generation tool supplied with Hibernate. If you create the schema in some other way you have to add the proper constraints in the CREATE TABLE statement yourself.

Thanks nordborg for the information
If anybody have any other thoughts please share..