From: Hammond, Tony [mailto:t.hammond@nature.com]
Sent: Tuesday, December 07, 2010 9:47 AM
To: Denenberg, Ray; OASIS SWS TC
Subject: RE: Facet limit
Hi Ray:
A couple comments about "facetLimit" - which btw should also apply equally to "facetCount" and "facetStart". (The parameter "facetSort" is global as I understand it.)
1. I note that the only repeatable parameters in the SRU spec are these listed facet parameters, the extension parameters, and "httpAccept". So there is a question as to whether SRU wants to support repeatable parameters - period. My proposal for "facetLimit" (and similarly for "facetCount" and "facetStart") was for a single (non-repeatable) compound value. I also query what real purpose repeatable "httpAccept" parameters serves. (I know that the Accept header allows for multiple values, i.e. a compound value. So should "httpAccept" also allow for compound values or should it be repeatable?)
Is there a case to be made for all SRU parameters (bar extension parameters) to be non-repeatable?
A counterpoint though might be that the values for some parameters could become cumbersome.
2. This proposal from Ralph was made to avoid the restrictions on index names that the delimiters I originally suggested would put in place. However, we still have similar restrictions on the "sortKeys" parameter which I would suggest is a more widely used parameter than "facetLimit". So we already have restrictions on index names which should be acknowledged somewhere.
3. The repeated "=" could be problematic for certain parsers.
Sorry if this creates more issues but I guess generally we are looking for simplifications and ease of use.
Tony