When you will create your entity you will only have to set the desc property. The 'id' property will be set since it has these @Id @GeneratedValue(strategy=GenerationType.AUTO) annotations. The database end depends upon the table generation strategy in your persistence.xml file. If this is what you have in persistence.xml: | <properties> | <property name="hibernate.hbm2ddl.auto" value="create"/> | </properties> | OR | <properties> | <property name="hibernate.hbm2ddl.auto" value="update"/> | </properties> Then you dont have to create the tables yourself, they'll be created. If you want to create the tables yourself then just like anyother column in a table you should also create the column for your id. The @GeneratedValue annotations generates only int, Long or String values(but do check for yourself). So you should check what should be the datatype of your id. Say i have a table Customer in db with property Number CUSTOMERID. In my entity Customer, i will have property Long customerId. Then i use: | @Id | @GeneratedValue(strategy=GenerationType.AUTO) It works fine. hope this helps! View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4024993#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...