l have a table without a Primary Key or Unique Key column. I need to manipulate this table from the Spring application by using JPA and Hibernate.
While I was trying to map this table’s entity, it fails because there's no @Id mapping.
I tried to make a composite id from all the entity properties to ensure uniqueness, but in this case, the entity has returned an immutable object.
I need to manipulate some variables of this entity. What should I do? To alter the table by adding a unique column will bring me new challanges. Is there a way without altering table?
Let's assume you wanted to change those records with SQL. How would you know which row to update or delete if you don't have a unique column?
Unless you create a unique column, there's nothing you can do about it.
There should be a unique way to identify your records. Sometimes, you have multiple columns. In this case, you use a composed primary key. In JPA, you can implement a composed primary key in two ways: @EmbeddedId or @IdClass.