How To Use @MapsId For Sharing Identifier In @OneToOne Relationships

Description: Instead of regular unidirectional/bidirectional @OneToOne better rely on an unidirectional @OneToOne and @MapsId. This application is a proof of concept.

Key points:

• use @MapsId on child side
• use @JoinColumn to customize the name of the primary key column
• mainly, for @OneToOne associations, @MapsId will share the primary key with the parent table (id property acts as both primary key and foreign key)

Note:

• @MapsId can be used for @ManyToOne as well

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