Gregor,

We disagree and I'd like to get to the reason why because I am sure that both of us are not fully understanding what the other is saying.

I agree that a character name is not necessarily unique across different taxa. A character is what a person defines it to be. But I don't understand what you mean when you say that the name cannot stand for the character, that only a code can. This seems absurd. I don't see the difference between my 'name' and your 'code', especially when your code is just a compact coding that refers to a name.

In your haircolor example, I think you are misunderstanding the hierarcical nature of XML coding. Each character is part of another, which all eventually are part of a 'root,' in our case probably a plant. So the character 'Plant' has the characters 'stems.' 'leaves,' etc. 'Leaves" may contain the character 'trichomes' which may contain the character 'color.'

If I understand what you wrote, your criticism applies to a relational model where the character of 'aircolor' might be used for leaf trichomes, fine enations inside a fruit, or the body covering of mammals. It is impossible to define a character this way in an XML file because it is strictly hierarcical, not relational.

If you feel that descriptive data can only be modeled with relations, then you can never get XML to work for you. It is not relational, it is strictly hierarcical. It does not and, by design, cannot support the relational model. Do not confuse XML with a database. It is -not- designed to be a database. The few databases that use XML are all hierarcical XML is designed to model the structure of documents. If you want to create a database, use a database language. XML is what you use in the report.

My feeling is that the hierarcical nature of XML might be suitable for plant descriptions. I know it does a good job coding taxomomic papers and taxonomic nomenclature. It is less suitable, though still workable, for specimen data, which is easier to model with relational tables.

To use XML though, I think we must look outside the DELTA model of character coding. XML won't improve the DELTA model or fix its faults. We must also look beyond the database model. Plant descriptions are highly structured documents. XML can model that structure.

Finally, we have to get beyond the wordiness of XML files. They are designed to be that way. we can only live with it.

Let me know if this makes sense and be sure to correct me if you feel I am being too stupid.

all the best,

Kerry

-----Original Message----- From: Gregor Hagedorn [mailto:G.Hagedorn@BBA.DE] Sent: Tuesday, November 20, 2001 10:31 AM To: TDWG-SDD@USOBI.ORG Subject: Re: is there an "xml-include"

Dear Kerry,

I can not see how what you propose could work. The name of a character is not necessarily unique across different taxa, and often not even within a taxon. Further the character concept and its names (technical, laymen, English, German, etc.) are a 1:n relation. The name can not stand for the character, only a code can. I do not care whether this code is characters or numbers, but I believe it is a mistake to think if something is <haircolor></haircolor> to take the code at face value and assume you know what are hairs and what is color. Hairs are quite different things in plants, animals, or fungi, and color needs information whether it is a code from a color comparison chart, or an undefined term like "red".

I think I am sticking less with a DELTA storage optimization model, but with a relational information model, which is what I have been using for all my projects. The relational model allows language independence. How can you preserve that, without having unique codes that lead to the definition of a character?

That does not mean, that a free text description in some language, say Chinese, may be present, in addition to the data. That is why I am thinking of attributes, not element data.

Gregor ---------------------------------------------------------- Gregor Hagedorn (G.Hagedorn@bba.de) Institute for Plant Virology, Microbiology, and Biosafety Federal Research Center for Agriculture and Forestry (BBA) Koenigin-Luise-Str. 19 Tel: +49-30-8304-2220 14195 Berlin, Germany Fax: +49-30-8304-2203

Often wrong but never in doubt!