The @Id makes it possible to uniquely identify the instances There are several ways to generate the primary key at java code level: for example: @Id @GeneratedValue(Strategy=GenerationType.Identity) Generation strategy: Identity as Autoincrement – The database management system will take care of the primary key generation in this case. Example: The id identiies uniquely identifies the …
When using jpa we need that one of the fields plays the role of a primary key In this case, the annotation used @Id will make use of reflection at field level JPA makes use of Inversion of Control Design Pattern Example how to use the Id annotation: The annotation is added above the fields …
We can start with Java code and let the JPA code create the tables Or we can first create the tables and then create the classes based on these tables We can get control as a starting point from the table or from the code Even if the tables are already created, we can use …