Firstly, thanks for putting this together.

I don't think that portability is a huge problem. I agree with the three
scenarios that Albert mentioned, but I think that we can refine #1:

> 1) if an application wants to be fully portable between providers, the
> standard orm.xsd must be specified. This will inhibit the use 
> of openjpa
> features.

I would revise this as follows:

1) if an application wants to be fully portable between providers, the
standard orm.xsd must be specified. This will inhibit the use of OpenJPA
features in that file, so a parallel openjpa-orm.xml file must be used
which conforms to the OpenJPA XSD and adds the additional information.

We could even create a second XSD for that situation that allows only
OpenJPA content to help prevent people from putting conflicting stanzas
in the two files.

-Patrick

-- 
Patrick Linskey
BEA Systems, Inc. 

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> -----Original Message-----
> From: Albert Lee [mailto:[EMAIL PROTECTED] 
> Sent: Wednesday, January 24, 2007 8:38 AM
> To: open-jpa-dev@incubator.apache.org
> Subject: Re: Using query hints for mapping extensions in orm.xml
> 
> First, I would not expected other providers will handle the special
> openjpa.orm.xsd even if it is spec'ed out in the document 
> header. If they
> choose to ignore the new schema and proceed to parse the 
> document content
> using the standard orm.xsd, then any openjpa specific stanza 
> will probably
> be flagged as non-compliance.
> 
> The other scenario is: what about if the document does not specify the
> schema at all, like the original sample. I suspect most providers will
> tolerate this scenario, just like openjpa does.
> 
> Can the solutions be:
> 1) if an application wants to be fully portable between providers, the
> standard orm.xsd must be specified. This will inhibit the use 
> of openjpa
> features.
> 2) if an application wants to use openjpa specific stanza and 
> still be used
> by other provider, don't specify the schema at all in the 
> document. Hoping
> the other providers will tolerate and ignore the openjpa features.
> 3) if an application wants to be openjpa schema compliance, then use
> openjpa.orm.xsd in the document header and openjpa can validate the
> document. However this will prevent the application to be 
> portable to other
> providers.
> 
> Albert Lee.
> 
> 
> On 1/24/07, Kevin Sutter <[EMAIL PROTECTED]> wrote:
> >
> > Thank you, Albert, for your experimentation.  The updated schema
> > definition
> > (openjpa_orm_1_0.xsd) and the example openjpa_orm.xml seems 
> to be what we
> > are looking for.  I guess the only concern is whether we 
> can count on
> > other
> > JPA implementations to ignore this extra schema definition 
> and just rely
> > on
> > the standard orm.xsd.
> >
> > Question:  Even if other JPA providers are smart enough to 
> ignore our
> > specialized schema and use the standard JPA schema, what 
> happens to our
> > extension elements?  Do they get ignored as well?  Or, will the
> > verification
> > step still trip over these new/updated elements?
> >
> > Thanks again,
> > Kevin
> >
> >
> > On 1/23/07, Albert Lee <[EMAIL PROTECTED]> wrote:
> > >
> > > Somehow the one of the attachment (openjpa_orm_1_0.xsd) 
> from my previous
> > > note did not make it to this forum.
> > >
> > > Try again here.
> > >
> > 
> --------------------------------------------------------------
> --------------------------------
> > >
> > > <?xml version="1.0" encoding="UTF-8"?>
> > > <!--
> > >     OpenJPA specific orm.xml schema locates in: (E.g.)
> > >
> > >
> > 
> http://incubator.apache.org/openjpa/xml/ns/persistence/openjpa
> _orm_1_0.xsd
> > > "
> > >
> > >     This schema extends
> > http://java.sun.com/xml/ns/persistence/orm_1_0.xsd
> > > with
> > >         OpenJPA specific stanza and uses the same name space as
> > >             "http://java.sun.com/xml/ns/persistence/orm";
> > > -->
> > > <xsd:schema
> > >                  version="1.0"
> > >                xmlns:xsd="http://www.w3.org/2001/XMLSchema";
> > >          targetNamespace=" 
> http://java.sun.com/xml/ns/persistence/orm";
> > >                
> xmlns:orm="http://java.sun.com/xml/ns/persistence/orm";
> > >       elementFormDefault="qualified"
> > >     attributeFormDefault="unqualified"
> > >   >
> > >
> > >   <xsd:annotation>
> > >     <xsd:documentation>
> > >       @(#)openjpa_orm_1_0.xsd 1.0  Jan 22 2007
> > >     </xsd:documentation>
> > >   </xsd:annotation>
> > >   <xsd:annotation>
> > >      <xsd:documentation><![CDATA[
> > >
> > >        This is the XML Schema for extending the persistence
> > > object-relational
> > >        mapping file for OpenJPA specific features.
> > >
> > >        The file may be named "META-INF/orm.xml" in the persistence
> > >        archive or it may be named some other name which would be
> > >        used to locate the file as resource on the classpath.
> > >
> > >      ]]></xsd:documentation>
> > >   </xsd:annotation>
> > >
> > >   <!-- Redefine the orm_1_0.xsd with additional OpenJPA 
> extensions -->
> > >   <xsd:redefine schemaLocation="
> > http://java.sun.com/xml/ns/persistence/orm_1_0.xsd
> > > ">
> > >
> > >     <!--
> > >         Append optional single <data-cache> element to <entity>.
> > >           Valid values are "true" | "false" | "1" | "0".
> > >           Default value is "false".
> > >     -->
> > >     <xsd:complexType name="entity">
> > >       <xsd:complexContent>
> > >         <xsd:extension base="orm:entity">
> > >           <xsd:sequence>
> > >             <xsd:element name="data-cache" type="xsd:boolean"
> > > minOccurs="0" maxOccurs="1" default="false"/>
> > >           </xsd:sequence>
> > >         </xsd:extension>
> > >       </xsd:complexContent>
> > >     </xsd:complexType>
> > >
> > >
> > >     <!--
> > >         Append optional single <jdbc-nonpolymorphic> element to
> > > <one-to-many>.
> > >           Valid values are "true" | "false" | "1" | "0".
> > >           Default value is "false".
> > >
> > >         Append optional single <jdbc-eager-fetch-mode> element to
> > > <one-to-many>.
> > >           Valid values are "parallel" | "others".
> > >           Default value is "parallel".
> > >     -->
> > >     <xsd:complexType name="one-to-many">
> > >       <xsd:complexContent>
> > >         <xsd:extension base="orm:one-to-many">
> > >           <xsd:sequence>
> > >
> > >             <xsd:element name="jdbc-nonpolymorphic" 
> type="xsd:boolean"
> > > minOccurs="0" maxOccurs="1" default="false"/>
> > >
> > >             <xsd:element name="jdbc-eager-fetch-mode" 
> minOccurs="0"
> > > maxOccurs="1" default="parallel">
> > >               <xsd:simpleType>
> > >                 <xsd:restriction base="xsd:string">
> > >                   <xsd:enumeration value="parallel"/>
> > >                   <xsd:enumeration value="others"/>
> > >                 </xsd:restriction>
> > >               </xsd:simpleType>
> > >             </xsd:element>
> > >
> > >           </xsd:sequence>
> > >         </xsd:extension>
> > >       </xsd:complexContent>
> > >     </xsd:complexType>
> > >
> > >   </xsd:redefine>
> > >
> > > </xsd:schema>
> > >
> > >
> > > Albert Lee
> > >
> >
> >
> 

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