Please Visit: http://ift.tt/1ajReyV
from Public RSS-Feed of Jeffery yuan. Created with the PIXELMECHANICS 'GPlusRSS-Webtool' at http://gplusrss.com http://ift.tt/1qwGjzD
via LifeLong Community
one to many - JPA @ManyToOne with CascadeType.ALL - Stack Overflow
The meaning of CascadeType.ALL is that the persistence will propagate (cascade) all EntityManager operations (PERSIST, REMOVE, REFRESH, MERGE, DETACH) to the relating entities.
It seems in your case to be a bad idea, as removing an Address would lead to removing the related User. As a user can have multiple addresses, the other addresses would become orphans. However the inverse case (annotating the User) would make sense - if an address belongs to a single user only, it is safe to propagate the removal of all addresses belonging to a user if this user is deleted.
BTW: you may want to add a mappedBy="addressOwner" attribute to your User to signal to the persistence provider that the join column should be in the ADDRESS table.http://ift.tt/1sEVRPh
http://ift.tt/1qwGkU0
The meaning of CascadeType.ALL is that the persistence will propagate (cascade) all EntityManager operations (PERSIST, REMOVE, REFRESH, MERGE, DETACH) to the relating entities.
It seems in your case to be a bad idea, as removing an Address would lead to removing the related User. As a user can have multiple addresses, the other addresses would become orphans. However the inverse case (annotating the User) would make sense - if an address belongs to a single user only, it is safe to propagate the removal of all addresses belonging to a user if this user is deleted.
BTW: you may want to add a mappedBy="addressOwner" attribute to your User to signal to the persistence provider that the join column should be in the ADDRESS table.http://ift.tt/1sEVRPh
http://ift.tt/1qwGkU0
from Public RSS-Feed of Jeffery yuan. Created with the PIXELMECHANICS 'GPlusRSS-Webtool' at http://gplusrss.com http://ift.tt/1qwGjzD
via LifeLong Community
No comments:
Post a Comment