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difference between joinColumn and PrimaryKeyJoinColumni

Senthil Kumar
Ranch Hand

Joined: Mar 13, 2006
Posts: 264
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..

when you really want something, all the universe always conspires in your favour.<br /> <br />SCJP1.5-77%<br />SCWCD-89%
Rodrigo W Bonatto
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Joined: Aug 20, 2004
Posts: 62

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.


Shivani Chandna
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Joined: Sep 18, 2004
Posts: 380
Usage of PrimaryKeyJoinColumn:

(1) For defining linkage to a secondary table:

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:

/** Code speaks louder than words */
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subject: difference between joinColumn and PrimaryKeyJoinColumni
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