Hibernate foreign key constrain multiple databases

Question

we have two databases currently build with hibernate using the “org.hibernate.dialect.PostgreSQLDialect” dialect, i.e. UsersDB and AttachmentsDB.

The question is: Is it possible to have a foreign key constrain in UsersDB referencing an UUID field in AttachmentsDB. If yes how should the @JoinColumn annotation look like? Or is it done in a different way?

Something like that:

@OneToMany(cascade=CascadeType.ALL)
@JoinColumn(name="ATTACHMENT_ID", database=”AttachmentsDB”)
@ElementCollection(fetch=FetchType.EAGER)   
private Collection<Attachments> attachment;

regards,

K

Answer 1

I suppose you could try something like

alter table UsersDB.Table1 add constraint UsersDB_FK_Constrain_to_UUID foreign key (UsersDB.Table1.user_uuid) references AttachementsDB.Table2.uuid;