In this inheritance strategy, mapping of the child class fields is done with the common fields of the parent class in a separate table. In other words, the common entities between the child classes and the parent class are mapped in the separate database table.

What is @JoinTable?

The @JoinTable is used to define the join/link table. The @JoinColumn annotation is used to specify the join/linking column with the main table. Here, the join column is employee_id and project_id is the inverse join column since Project is on the inverse side of the relationship.

What is the use of @JoinTable annotation?

The @JoinTable annotation indicates that we will interact with the intermediary table (user_roles) and further you can see settings of the relationship including mapping of columns.

What types of joins can you use in Hibernate?

Hibernate supports 4 types of joins..

  • Left Join.
  • Right Join.
  • Full Join.
  • Inner Join.

Is Join left or inner?

INNER JOIN: returns rows when there is a match in both tables. LEFT JOIN: returns all rows from the left table, even if there are no matches in the right table. RIGHT JOIN: returns all rows from the right table, even if there are no matches in the left table.

What is joinColumns and inverseJoinColumns?

joinColumns: Assign the column of third table related to entity itself. inverseJoinColumns: Assign the column of third table related to associated entity.

What is inverseJoinColumns in hibernate?

InverseJoinColumn is used to customize the column name in the table of the associated class reference variable name. that column act as a foreign key.

What is Hibernate ManyToOne?

​ The @ManyToOne annotation is used to create the many-to-one relationship between the Student and Address entities. The cascade option is used to cascade the required operations to the associated entity. If the cascade option is set to CascadeType. ALL then all the operations will be cascaded.

What is referencedColumnName in @JoinColumn Hibernate?

24. Quoting API on referencedColumnName: The name of the column referenced by this foreign key column. Default (only applies if single join column is being used): The same name as the primary key column of the referenced table.