Re: [search-ws-comment] XML Schema design for search WS

[Saašha Metsärantala <saasha@acc.umu.se>]

Hello!

> The OASIS WS TC thanks you for
> your comment of January 16
> about schema design.
Thanks Ray for your answer!

> There is no single "right way"
> to design a schema
That is true!

> valid instances can be created
> which make no sense for the
> searchRetrieve application.
I would like to try to avoid that.

> In our schemas we have chosen
> to define each element as
> global so that it can be
> imported by another schema.
That represents a valid approach, of course!

> there may be other applications
> [...] that may want to [...]
> reference to specific elements.
Of course, it is important to take that into account.

> it seems simpler [...] to
> globalize all elements rather
> than arbitrarily (or best guest)
> select some but not others.
It is!

I would like to suggest to combine these approaches. This could be done in 
different ways. One example is the following:

We could create one new schema where all elements defined there can be 
root elements.

The other schemas would be rewritten to mainly select and combine the 
elements defined in the new schema and define which elements are allowed 
to be used as root elements.

Thus, we could prevent many non-sense instances to validate without giving 
up the reusability of most elements.

Of course, one more schema would slightly increase the complexity of the 
overall design, but I consider that the flexibility such an approach can 
offer would combine well with the ability to avoid the validation of many 
non-sense instances.

Future versions of the new schema could add new elements without removing 
nor modifying previously defined elements, thus improving its forward 
compatibility. Future versions of the other schemas could focus on new 
ways to combine (previously defined or newly defined) elements.

Regards!

Saašha,