[OAI-implementers] thoughts and warnings about schemas ...

Hussein Suleman hussein@vt.edu
Sat, 31 Mar 2001 17:24:12 -0800


im going to prefix whatever i say by saying that if you're not
interested in the nuts-and-bolts of schemas and their implications for
us, dont worry too much about this email ... its more a heads-up than
anything else ...

so, has anyone else noticed that the target is moving once again ? the
W3C released a "proposed recommendation" approximately 2 weeks ago ...
yes, with changes ... they changed the basic data type names for
"number" (and changed it back already!) and "URI" and "timeInstant" ...
(the only reason i noticed was because i was using a timeInstant and it
wasnt listed in the online copy of the schema documentation)

so, what does this mean for us ? cant we just keep our old schemas in
the old format and write new ones in the new format ? well, maybe ... im
still trying to figure out how thats going to work ... i've already
picked up a few problems:

- old schemas wont validate in the new checker
- new schemas wont validate in the old checker (ok, that may be obvious
- the new software doesnt install locally (with profound implications
for validation through the repository explorer - i just sent off a long
note to the schema developers mailing list asking for help)
- the new spec has very little software support thus far

personally, im sitting this out until the new software is working
properly ... the old stuff works and im going to keep on using the old
spec until i have the same degree of confidence in the new spec/software
... i would recommend to anyone else writing schemas to do the same for
now ... which means that if you try schema validation, make sure to go
to the old "October 2000" version from the W3C online XSV validation ...
or just trust the repository explorer's validation (which is the same
software - i just have it installed locally on my server)

there are a few more complicated problems i foresee ... but lets fix the
simple ones first :)


hussein suleman -- hussein@vt.edu -- vtcs -- http://purl.org/net/hussein