序列发生器在 Oracle 18c 上不起作用

Question

I have a table with columns id and name which I am creating using this class.

@Entity
@Table(name = "xyz")
public class XYZ implements Serializable{
   
    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "some_gen")
    @SequenceGenerator(name = "some_gen", sequenceName = "some_seq", allocationSize = 2)
    @Column(name = "id")
    private Long id;

    @Column(name = "name")
    private String name;
    
    //Getter Setter NoArgConstructor AllArgsConstructor


}

Now when I run this, table as well as sequence is created. Verified it from SQL Developer. But when I run the following statement I am getting following error.

INSERT INTO xyz (name) VALUES ('John');

ORA-01400: cannot insert NULL into ("SOME_USER"."XYZ"."ID")

I am using JPA and Spring Boot.

//This is MyBatis. It will be triggered by REST API
@Mapper
public interface XYZMapper {

    @Insert("INSERT INTO xyz (name) VALUES (#{name})")
    public void addNewName(XYZ xyz);
}

Answer 1

I don't know Java.

But, from Oracle's point of view, the fact that you generated the sequence doesn't mean that Oracle will automagically use it. You have to either use it directly, such as

insert into xyz (id, name) values (some_seq.nextval, 'John');

or create a database trigger which will do it for you:

create or replace trigger trg_bi_xyz
  before insert on xyz
  for each row
begin
  :new.id := some_seq.nextval;
end;
/

and now you can use insert you previously posted:

INSERT INTO xyz (name) VALUES ('John');