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From Murach's Java Servlets/JSP 3rd edition Question about example of Primary Keys in JPA entity.  RSS feed

 
Lisa Austin
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Hi there,
on page 428 - 429 of the book it explains if add the @Id annotation the annotation tells JPA that the following field is the primary key for the entity. If you use @GeneratedValue annotation it tells the JPA to automatically generate values for the primary key.

I just want to clarify. In the example and explanation this mean that the primary key is userID and the values are auto generated? Just checking that I understand . Thanks!!


A simple JPA entity

 
Stefan Evans
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Your understanding sounds fine to me.

userId is indeed the field which is being annotated here
 
Lisa Austin
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Stefan Evans wrote:Your understanding sounds fine to me.

userId is indeed the field which is being annotated here


Thank You. I wasn't too sure i it was JUST that field or all fields under it.
 
It is sorta covered in the JavaRanch Style Guide.
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