At 07:15 AM 1/11/2005, Mike Taylor wrote:
>[...]
>Also for the record (thank, Rob!) Eliot is incorrect in supposing that
>I think it's OK for CQL indexes in different context sets to have
>different names. Far from it: as a matter of Good CQL Citizenship,
>anyone defining a new context set should take pains to ensure that
>they do not duplicate the semantics of an index already defined
>elsewhere. [...]
Sorry, I guess I misunderstood Mike's position in a prior
exchange. I will try to present the "multiple index names
with same semantics" issue as I see it.
I think it is reasonable to have CQL accommodate current
practice in the naming of indexes for existing communities
of practice. This has already been done to some extent
with bibliographic terminology in anticipation that CQL
will be used by the library community. But, the library
community is only one among a great number of communities
that ought to use CQL.
If CQL is to also be used for the searching of news stories,
we can anticipate that there will be a "news context set"
wherein the index named "byline" would have the same semantics
as "author" and the index named "headline" would have the same
semantics as "title". If CQL had a rule that prohibited more
than one index name for the same semantics, the result would
surely be that the news context set author/creator would insert
some trivial difference in the semantics so that the community
can write CQL using the index names that are natural for them.
Then, CQL would have encouraged an artificial barrier to search
interoperability: two indexes that ought to have been the same
for almost all search purposes have been made to seem different.
Obviously, any search server supporting CQL must provide some
kind of semantic mapping function to relate named indexes to
particular pieces of content. It is expected that such a
function will often map multiple index names to the same
content. Since only the human who sets up that mapping is
responsible for how "good" is the semantic match, I don't
see why we would want to have CQL playing "semantics cop".
Eliot
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