one to many the same class spring data (hibernate)

Question

I want to make a relation one to many with the same class java using hibernate (spring data)

this is my code

@Data
@Entity
public class TemplateData implements Serializable{

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    @ManyToOne
    private TemplateData div;
    @OneToMany(mappedBy="div")
    private Collection<TemplateData> baseCSS;

    private int position;
    private String data;

}

and I get this error

HHH000388: Unsuccessful: alter table add constraint template data FK_y1mi9blsbc08tmwm9jgvdd1b foreign key (template_data_id) references template_data
ERROR: "template_data" relationship does not exist

Is the table in the database that your entity is mapped to called "template_data"? If not, you should consider using the @Table annotation, i.e. @Table(name = "my_template_data"). Alternatively, if you want to rely on the ORM to generate the table structure, you should check if the generateDDL flag is enabled in the ORM config. — Cristina_eGold, Jul 25 '16 at 13:48
I added this I still not working @Table(name = "template_data") . — khalil _diouri, Jul 25 '16 at 14:05
Can you share the table structure (the table name, along with all the columns and data types)? — The Student Soul, Jul 25 '16 at 14:10
this is the structure of table in the question code table is not created in my database — khalil _diouri, Jul 25 '16 at 14:11
Humour us and give us a short description of your table, as the error makes it sound like it is not exactly called "template_data" in the DB, but something else. — Cristina_eGold, Jul 25 '16 at 14:19
when I made // private int order; as comment it works ?? what is this ! — khalil _diouri, Jul 25 '16 at 14:23
Edit your question or provide an answer to include the new, working version and well as your broken version. Otherwise, this question is of little value to later visitors. — JudgingNotJudging, Jul 25 '16 at 16:52

score -1 · Answer 1 · edited May 23 '17 at 11:44

Sometimes this problem occurs when we use

hibernate.hbm2ddl.auto=create-drop

You can fix this by changing the hibernate.hbm2ddl.auto to update:

hibernate.hbm2ddl.auto=update

You can go through this tutorial.

Mikko Maunu suggested that

Combination of create-drop and in-memory database produces these for every database object it tries to drop. Reason being that there is not any database objects to remove - DROP statements are executed against empty database.

Also with normal permanent database such a errors do come, because Hibernate does not figure out before executing DROP statements does added object exist in database or is it new.

Resource Link:

Unsuccessful: alter table XXX drop constraint YYY in Hibernate/JPA/HSQLDB standalone

one to many the same class spring data (hibernate)

1 Answers1

Resource Link: