Multiple Query Types

["LeVan,Ralph" <levan@oclc.org>]

I’d like to bring up the topic of multiple query types again.

 

I think we have eliminated the use of a query-type parameter as a solution.  This would have used the query parameter to carry queries of all types and the query-type parameter would have specified how the query was to be interpreted.  Explain records would have listed the types of queries supported by the server.  The objection to this parameter is that it adds another parameter to the query (and the documentation).

 

A simpler solution is to use the name of the query parameter itself to indicate the type of query.  For instance, our current query parameter might be renamed CQLQuery and a new query parameter of LuceneQuery might be specified to support Lucene queries.

 

One way to do this would be to have the standard specify the parameter to be used for every type of query we can think of.  The Explain record for the database would again list the supported query types.  This simplifies interoperability, but leaves the standards body with the perpetual task of adding new search types.

 

My preference is that the standards body not specify the name of the query parameters.  Instead, the Explain record, which already lists the supported query types, also specify the name of the associated query parameter.  This allows for much easier local extensibility.

 

The objection to this scheme is that trivial interoperability goes away: SRU URLs cannot be constructed without reference to the Explain record.

 

So, here’s my compromise position:  do it my way.  Well, that and have the standards body create a profile where we specify the names of the parameters for query types that we think might be useful/common.

 

Feedback would be appreciated!

 

Ralph