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From Ilan Kirsh <ki...@objectdb.com>
Subject Re: JDO2 annotations : split between JDO and ORM
Date Sun, 15 Oct 2006 15:23:22 GMT
Hi Andy,

I agree that mappedBy should remain in Field. Same is true for indexed,
unique, deleteAction, sequence and valueStrategy, which can all  be
useful also for object databases. I think that only table, column and
columns are specific for relational databases. Same is applied also for
Element, Key and Value, which were moved to orm.

I am not sure how a composite index should be declared using
annotations. Assuming that this is done using index and unique -
these two are also relevant to object databases.



----- Original Message ----- 
From: "Andy Jefferson" <andy@jpox.org>
To: "JDO Expert Group" <jdo-experts-ext@sun.com>; "Apache JDO project"
Sent: Sunday, October 15, 2006 1:39 PM
Subject: JDO2 annotations : split between JDO and ORM

> An initial split of JDO and ORM annotations is at :-
> JDO :-
> http://jpox.cvs.sourceforge.net/jpox/JPOX/Plugins/Java5/src/java/org/jpox/annotations/
> ORM:-
> http://jpox.cvs.sourceforge.net/jpox/JPOX/Plugins/Java5/src/java/org/jpox/annotations/orm/
> Still to do :
> @DatastoreIdentity currently has columns, indexed, etc. This will need
> splitting off into its own class-level annotation
> (@DatastoreIdentityColumns)
> @Version currently has columns, indexed etc. This will need splitting off
> into
> its own class-level annotation (@VersionColumns)
> @PersistenceCapable has joins. This can be replaced by the @Joins
> annotation.
> @Field has table, unique, columns, delete-action, indexed. These will need
> replacing by things like @JoinTable, @SecondaryTable, @Columns
> Also some possibilities in the DTD/XSD are not currently specifiable using
> annotations (e.g extensions on all main elements). We should aim to have
> an
> equivalent specification in annotations that we can do in metadata (though
> noting IIRC that JPA does not abide fully by this with some things being
> specifiable in metadata that annotations aren't flexible enough for).
> I'd be interested to see any proposed split that others have come up with.
> PS. Is it so essential to split off the "mappedBy" attribute of <field>
> into
> ORM ? It exists to define both ends of a bidirectional relation, and so
> would
> be used by Managed Relationships irrespective of whether the datastore is
> RDBMS (which is the principal target of such an "ORM" split).
> -- 
> Andy

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