P14: questions

[Martin Hardwick]

Jochen,

The STEP Tools opinion on your questions is inserted into the text
below. The text of the P14 DIS is currently in Geneva waiting distribution
to the countries for balloting.

Martin

At 03:06 PM 5/23/2002 +0200, Jochen Haenisch wrote:
>Dear WG11 experts,
>
>focus has recently been on P11e2 - maybe I can get some attention for P14
>?!?
>
>We have a couple of questions:
>1) 9.10 Rule declaration:
>Rules may be defined for use within a schema_view. What is the intention of
>this feature? Shall these rules control the population of the view_entities
>in the schema? Or shall they (also) have an impact on the referenced
>original population? The latter does in our opinion not make too much sense,
>but maybe there are examples that we have not thought of?!?
>Similar for schema_map.

The intent of this feature is to allow a schema_view to define constraints
on the population of a view. There should not be an impact on the original
population.

For the DIS ballot STEP Tools is going to suggest that a VIEW should also
be able to define local rules (WHERE and UNIQUE) that further constrain/describe
the population of a view. To enable this change we will also suggest changing
the keyword of the WHERE clause in the header of a VIEW to WHEN.



>2) Reference to populations:
>Is the only way of identifying populations the FROM-clause (binding extent)?
>What if one wants to change a single population? Then source and target
>schema are the same. In such a case it is necessary to have names for source
>and target populations, not only for the schemas.
>Or is this out of scope for P14?

The STEP Tools position is that this is out of scope.



>Thanks for your attention!
>Best regards, Jochen.
>____________________________________________________________
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