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Bidirectional - Only one @JoinColumn

Sandeep Vaid
Ranch Hand

Joined: Feb 27, 2006
Posts: 392
"Note that you do not have to define @JoinColumn in the entities of both sides of one-to-one relationships."
Does this mean that we "Do Not Have To" OR "We Can't" define @JoinColumn in the entities of both sides of one-to-one

Moreover [P-279p Of EJB3 In Action Book States:
"Note that the exact @JoinColumn specification could have been repeated for both the Bid.item and Item.bids
persistent fields on either side of the relationship."

The contradiction of this statement is @ [P-280]
"The persistence provider will generate deployment-time errors if you specify @JoinColumn on both sides of a
bidirectional one-to-many relationship."

Does this mean repetation of @JoinColumn is allowed in "OneToMany - ManyToOne" case but not allowed in bidirectional
"OneToOne" ?
I agree. Here's the link:
subject: Bidirectional - Only one @JoinColumn
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