A beta version of the GEDCOM XML Specification Release 6.0 has been published, including a chapter dedicated to the GEDCOM XML Document Type Definition. GEDCOM (Genealogical Data Communication) is widely considered the de facto standard for structured genealogical information, being designed "to provide a flexible, uniform format for exchanging computerized genealogical data." Having evolved over fifteen years, GEDCOM XML uses Unicode instead of the 8-bit ANSEL character set. It makes use of unidirectional (ID - IDREF) links that can be specified in only one way instead of the GEDCOM bidirectional linking mechanism.
Bibliographic information. GEDCOM XML Specification Release 6.0. Beta Version. Prepared by the Family and Church History Department The Church of Jesus Christ of Latter-day Saints. December 6, 2002. 55 pages. See especially Chapter 2: "GEDCOM XML Document Type Definition (DTD)." Contact: GEDCOM CoordinatorC3T.
Excerpted from the Version 6.0 Beta specification: "Although GEDCOM XML is different from traditional GEDCOM both in syntax and underlying logical structure, it is still considered as an evolution of GEDCOM... An important part of GEDCOM is its ability to link records according to family lineage and other data relationships. XML's standard linkage method, using the ID and IDREF attributes, is equivalent to traditional GEDCOM's linkage method and will be used in its place. In traditional GEDCOM, links are bi-directional. For example, a CHIL tag in the FAM record connects a family to a child, and a FAMC tag in the INDI record connects a child to a family. Also, HUSB and WIFE tags in the FAM record connect to INDI records, and in the opposite direction, FAMS tags in the INDI record handle both spouses' connection to a FAM record. To specify a link in both directions is, of course, redundant and unnecessary. Some programs produce traditional GEDCOM with links in one direction, some the other, and some give both. That makes processing GEDCOM from a variety of sources difficult, and where both directions are specified, they may be inconsistent. In GEDCOM XML, all links are unidirectional and can be specified in only one way... In the past, ANSEL has been specified as the preferred character set for GEDCOM; in GEDCOM XML, the UNICODE character set is used."
Genealogy XML Discussion List. The YahooGroups GenealogyXML List for Genealogy XML Schema is a popular forum for discussing the use of XML for genealogical data. Post to GenealogyXML@yahoogroups.com. "The purpose of this group is to discuss the application of XML to genealogical projects. Potential topics include XML, specifications on how XML should be used for genealogical reporting, vocabularies like GedML, GeniML, and GEDCOM 6.0, conversion of GEDCOM to XML, genealogy visualization tools, advice on XML and XSLT, and so on. Although this group is not a genealogy standards committee, discussion of current/proposed standards and models are viable topics."
Principal references:
- GEDCOM XML Specification Release 6.0. [cache]
- GEDCOM 6.0 Beta XML DTD (initially published only in the PDF document, with no official plain-text version)
- XML DTD. Draft version from Lee Brown. Updated version of DTD originally posted to the 'GenealogyXML@yahoogroups.com' list. 2002-12-30 or later. Comments describe the valid formats and values for certain elements and attributes that are described in the spec but not enforced by the DTD..." [source]
- XML DTD. Draft version of the XML DTD for GEDCOM XML 6.0 Beta. Posted by Harry Erwin to the GenealogyXML List, 2002-12-27 ("I've posted a transcription of the GEDCOM 6.0 DTD...it's likely to have errors, so take a look and let me know...") [source]
- XML DTD. Draft version of the XML DTD for GEDCOM XML 6.0 Beta. Posted by Nolan Voight: "I copied (and removed the page refs from) the DTD from the pdf to a text file; it works okay when declared as the doctype for an xml document in jEdit, autocompletions & all..." [source]
- GEDCOM to DAML. "ged2daml is a program for converting selected GEDCOM information into DAML... Generated DAML can be viewed using DAML Viewer. ged2daml was initially developed for DAML Homework Assignment 3. Lessons learned and other information is available here. The DRC concurrently developed a very similar GEDCOM ontology..."
- See also: XGenML website
- "Genealogical Data and XML" - Main reference page.