Win a copy of Learn Spring Security (video course) this week in the Spring forum!
  • Post Reply
  • Bookmark Topic Watch Topic
  • New Topic

difference between joinColumn and PrimaryKeyJoinColumni

 
Senthil Kumar
Ranch Hand
Posts: 264
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
i have seen these two annotations used when we want to relate two entities.
what i want to know is how one differs from the other..
 
Rodrigo W Bonatto
Ranch Hand
Posts: 62
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi

You can use joinColumn to define a join column in the table that references the primary key of the associated table.
PrimaryKeyJoinColumn is a little diferent and much easier when the primary key of the related entities are identical, so you do not need to specify a join column.

Regards,
 
Shivani Chandna
Ranch Hand
Posts: 380
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Usage of PrimaryKeyJoinColumn:

(1) For defining linkage to a secondary table:
@SecondaryTable(name="EMP_ADDRESS",
pkJoinColumns=@PrimaryKeyJoinColumn(name="EMP_ID"))

(2)
When no additional foreign key column in either table.In this case, @PrimaryKeyJoinColumn is used instead of an @JoinColumn annotation.


Usage of JoinColumn:

A relationship mapping where one table has a reference to another table.
i.e existence of foreign key column. In JPA its called join columns and
@JoinColumn annotation is the primary annotation used to configure these types of columns. Eg:

 
  • Post Reply
  • Bookmark Topic Watch Topic
  • New Topic