What is referencedColumnName used for in JPA?

hibernate jpa orm eclipselink openjpa
ams picture ams · Jun 28, 2012 · Viewed 103.6k times · Source

In JPA there is an attribute called referencedColumnName that can be set on @JoinColumn, @PrimaryKeyJoinColumn what is the idea behind this setting, can someone give a good example of where this can be used?

Answer

Firo picture Firo · Jun 28, 2012

It is there to specify another column as the default id column of the other table, e.g. consider the following

TableA
  id int identity
  tableb_key varchar


TableB
  id int identity
  key varchar unique

// in class for TableA
@JoinColumn(name="tableb_key", referencedColumnName="key")

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