XML databases [ was: S.O.D.A. database Query API - call for comments ]

Carl> Instead it developed into a discussion that questioned the usefulness of Carl> object databases.

To be fair, this is frequently because advocates of OODBMSs, at least in the past, have tried to slight RDBMSs. This time and again proves an uphill battle. This is indeed not very helpful, because I too hope that both 'camps' can learn from each other.

>> - language independent
>> - complex queries (XPATH), both navigational and value oriented
>> - normalization is up to the database
>> - assembling of data into meaningful larger groups (master-detail) is done
>> by the server

Carl> Be careful what you post here. Lee Fesperman tries to point out, that all Carl> the points you mention are negative.

Carl> - "language independant" ??? Language independance is not possible. You are Carl> using XML, aren't you?

he prolly meant application language independent. Granted, I don't know of any COBOL XML parser libraries, but the claim is not so extraordinary.

Carl> - "both navigational and value oriented" are very bad because two different Carl> methods to access data add complexity.

and power, methinks.

Carl> - "normalization is up to the database" does not work because it does not Carl> allow reuse.

that's up to the administrator.

Carl> - "assembling of data into meaningful larger groups" ??? Now what is Carl> that?

objects, I suspect :-)

Carl> It this proved by relational theory? You are bound to get Carl> redundant and misplaced data.

not anymore than with other technologies.

Carl> Personally I dislike XML since:
Carl> - it needs to be parsed.
Carl> - repetitive tags produce unnecessary overhead.

yup. But surely we'll soon have some dedicated encoding which can cut this down considerably (and gzip already routinely compresses XML down to less than 30% of the original).

Carl> - it is very unefficient in representing complex linked structures.

Same as above.

Carl> The widespread use of XML only proves the inability of the IT industry to Carl> work together on a clean data representation protocol.

Carl> XML is an O.K. format for exchanging very simple documents. It's use as a Carl> database protocol

well ... protocol ... no. The XML hierarchical queries do seem to offer an interesting perspective not offered by RDBMSs. To me it's vaguely reminiscent of parts of OQL, with the added benefit that it is standardized and implemented.

Carl> is a waste of performance and efficieny.

Yes, but this may not be such a big deal in many circumstances.

                                                                      Philip

-- 
If you have a procedure with 10 parameters, you probably missed some. (Kraulis)
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