EOS Persistence Entity

Source: Internet
Author: User

Persisting Entities

2009-11-30 20:53:38|  Category: Notebooks _ Learning Notes | Tags: | Report | Font size Big medium small subscription

In the entity definition of EOS, if the associated entity is used, the foreign key attribute of the primary entity is nonexistent and inaccessible.

For example, the above example: Ooperator/orgid This property does not exist and must be ooperator/oorg/orgid to access the number of the organization where the operator is located.

This approach is completely different from the way we use the database, because we are building a business domain object model that only oorg this object in the Ooperator object, OrgID This property must depend on a Oorg object to be able to exist.

In addition, when one side of a reference is a multi-end, it cannot be accessed by/and can only be taken to child objects as shown in the following way:

The Roomid (foreign key) in Bookroom is the primary key in the guest box, and when the above relationship is established, Roomid in Bookroom can only be obtained by BOOKROOM.ROOM.ROOMID.

EOS Persistence Entity

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