Suppose I have a table without any primary key (i.e table has duplicate records). Now i want to develop a BMP that will manipulate this table. It is said that an entity bean represents a unique record in some persistence database table. So how will it associate the entity bean EjbOject with a unique record in databse since table has duplicate records. What is the purpose of primary key class in this case ? Is primary key required or not ? How is it possible to handle such type of situation with Entity beans. Thanks in advance.