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Subject: RE: [ubl-lcsc] RE: [ubl-ndrsc] Functional Dependency and Normalization paper
I admit it is has been a few months since I last participated in the UBL NDRSC or LCSC discussion threads or telecons. So forgive me if I am missing something from the previous discussions. The concept of associating any XML data-containing-tag with a universal ID that captures the complete semantics of the root-to-leaf tree structure is the fundamental foundation of the UDEF naming convention and its derived ID. The UDEF naming convention is relatively simple and 100% conformant to the ISO 11179. My observation is that the ebXML Core Components approach is very complex and misses the mark in the proper interpretation of ISO 11179. I highly recommend that the teams take a close look at ISO 11179 part 1 - especially Figures 6-1, 7-1, and B-1. Collectively, these figures provide the comparison to the relational systems that nearly all back-office systems are based upon - especially the larger Fortune 500 companies and large government organizations. Attached is a spreadsheet from EIDX that illustrates the UDEF names and IDs as they are correlated to an example purchase order across several standards such as OAG, X12, RosettaNet, EDIFACT, and others. In addition to the Aerospace Industries Association (AIA), the Electronic Industries Data Exchange (EIDX) has adopted the UDEF approach as the means to integrate across the wide spectrum of XML standards. If UBL is not ready yet to listen - I will again return to my observation post. Ronald L. Schuldt Senior Staff Systems Architect Lockheed Martin Enterprise Information Systems 11757 W. Ken Caryl Ave. #F521 MP DC5694 Littleton, CO 80127 303-977-1414 ron.l.schuldt@lmco.com -----Original Message----- From: Burcham, Bill [mailto:Bill_Burcham@stercomm.com] Sent: Wednesday, September 11, 2002 9:17 AM To: 'ubl-ndrsc@lists.oasis-open.org'; 'ubl-lcsc@lists.oasis-open.org' Subject: RE: [ubl-lcsc] RE: [ubl-ndrsc] Functional Dependency and Normaliz ation paper (my citation software stinks, so I must ask your forgiveness for always responding at the head of the thread) Further (along Eve's thread) it's interesting to note that without any use of ID and IDREF or KEY and KEYREF the instance documents resulting from the normalized (3NF) schema in Tim's example are non-normalized in at least one important sense. While the _schema_ has been normalized, the instance document still contains repeated records=objects=content. We've got an approach to normalize the XML Schema -- which is essentially like a database schema. What we do not have is an approach to normalize the _serialization_ of structures conformat to that schema. This is an area for innovation -- relational theory doesn't have a serialization problem. The database is everything. We've got two views here (kind of). An almost-database view (XSD) and (possibly many) serialized views of that. I agree that we in NDR need to tackle the issues around IDREF and friends, and further, that it needs to be done in the context of our normalization discussion. Also, I think that the issue of normalizing the serialization falls pretty cleanly under the NDRSC charter and expertise. With our joint work on normalization of the logical model as a starting point it seems like NDRSC ought to be able to go forth and tackle the serialization. -Bill -----Original Message----- From: Eve L. Maler [mailto:eve.maler@sun.com] Sent: Wednesday, September 11, 2002 9:50 AM To: 'ubl-ndrsc@lists.oasis-open.org'; 'ubl-lcsc@lists.oasis-open.org' Subject: Re: [ubl-lcsc] RE: [ubl-ndrsc] Functional Dependency and Normalization paper Tim McGrath wrote: > Burcham, Bill wrote: >> In 1NF (in appendix A) at the point where you've found the one-to-many >> relationship between "order" and "order item" and you've shown the >> need (in >> the relational model) for the "linkage" from "order item" back to "order" >> via the foreign key. It seems worth noting at that point that this >> linkage >> is explicit in the relational model but implicit in the (eventual) XML >> one. >> This linkage between "order" and "order item" will be inferred from the >> context -- an "order item" is associated with the "order" under which it >> appears. We'll see this again and again. >> > I see the terms linkage, relationship and association as fairly similar. > In a relational model these are implemented by foreign keys, in XML by > including the associated element within the container (sorry, the > language gets in the way here - maybe we should just get down to > diagrams!). It is just different ways to implement the same concept. > Not sure i like 'explicit' and 'implicit' - we could just say that one > may be more elegant. XML's primary means of association is containment, but it also allows for association by reference. The built-in XML datatypes of ID and IDREF[S] are one way, and XSD provides another that it actually calls "keys", a la RDBMS's. (Personally, though, I think it's still high-risk to use the XSD key mechanism.) You can also invent any number of application-specific linking mechanisms, or even use the Web's URI paradigm for addressing resources. The NDR group has been trying to get to the topic of how to do content-by-reference and it looks like we'll have to push this higher in the stack... Eve -- Eve Maler +1 781 442 3190 Sun Microsystems cell +1 781 883 5917 XML Web Services / Industry Initiatives eve.maler @ sun.com ---------------------------------------------------------------- To subscribe or unsubscribe from this elist use the subscription manager: <http://lists.oasis-open.org/ob/adm.pl> ---------------------------------------------------------------- To subscribe or unsubscribe from this elist use the subscription manager: <http://lists.oasis-open.org/ob/adm.pl>
Attachment:
EIDXPOelement_extractapr2002ver15-UDEF.xls
Description: MS-Excel spreadsheet
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