Ray Denenberg, Library of Congress writes:
 > > The irony is that Z39.50 actually make _much_ more effort to
 > > specify semantics than most other standards -- and yet still
 > > finds itself in the situation where many implementations do not
 > > respond correctly to the BIB-1 attribute 6=3
 > > (completeness=complete field) which is how Eric should be able to
 > > do what he wants here.
 > >
 > > Not that I have any good answers to this problem ... but I DO
 > > know that inventing more and more replacement standards it NOT
 > > the answer.  Everything that's come along since Z39.50 has
 > > suffered from exactly the same problem but more so.
 > 
 > I think this remains to be seen for SRU/CQL, in particular for the
 > example at hand, how to search for exact title.  There are two
 > related issues: one, how arcane the standard is, and two, how
 > closely implementations conform to the intended semantics. And
 > clearly the first has a bearing on the second.
 > 
 > And even I would say that Z39.50 is a bit on the arcance side when
 > it comes to formulating a query for exact title. With SRU/CQL there
 > is an "exact" relation ('exact' in 1.1, '==' in 1.2).  So I would
 > think there is less excuse for a server to apply a creative
 > interpretation. If it cannot support "exact title" it should fail
 > the search.

IMHO, this is where it breaks down 90% of the time.  Servers that
can't do what they're asked should say "I can't do that", but -- for
reasons that seem good at the time -- nearly no server fails requests
that it can "sort of" fulfil.  Nine out of ten Z39.50 servers asked to
do a whole-field search and which can't do it will instead do a word
search, because "it's better to give the user SOMETHING".  I bet the
same is true of SRU servers.  (I am as guilty as anyone else, I've
written servers like that.)

The idea that "it's better to give the user SOMETHING" might -- might
-- have been true when we mostly used Z39.50 servers for interactive
sessions.  Now that they are mostly used as targets in metasearching,
that approach is disastrous.

 _/|_	 ___________________________________________________________________
/o ) \/  Mike Taylor    <[log in to unmask]>    http://www.miketaylor.org.uk
)_v__/\  "I try to take one day at a time, but sometimes several days
	 attack me at once" -- Ashleigh Brilliant.