How can I mapp the property when I want to avoid the duplication of perticular property which is not primary key of the data base.

For example I have one pojo class called LoginPojo

it has following fields

Integer userId
String userName
String userRole
String userPassword

The primary key of the login table is USER_ID which is mapped with the userId field. But I want the userName should not duplicate means two user can't have the same userName.

Is there any way to avoid this at the time of mapping.

Use the unique="true" attribute:


Note that this only affects the schema generation tool that will create an appropriate constraint on the database column.