> Date: Wed, 8 Feb 2006 15:49:01 -0500
> From: Jose Blanco <[log in to unmask]>
> 
> As an SRU gateway, do we have to be able to support all possible CQL
> queries?

You've already had good replies, but I just want to comment on this
part.  You _are_ supposed to be able to _parse_ all of CQL, but you
don't have to _support_ it all.  In other words, you're supposed to
understand the query well enough to be able to return an informative
diagnostic explain what precisely your implementation doesn't support,
rather just throwing your hands up and saying "I can't parse this
query".

To that end, if you're working in Java, Python, C/C++ or Perl, you can
and probably should use one of the fine open source CQL parser that
are linked from
	http://zing.z3950.org/cql/

Hope this helps.

By the way, good for you!  If there's one thing SRU needs it's more
implementations, so I'm delighted that you're doing this work.  We
(the community) will be pleased to help however we can.

 _/|_	 ___________________________________________________________________
/o ) \/  Mike Taylor  <[log in to unmask]>  http://www.miketaylor.org.uk
)_v__/\  "There is a huge switching cost to using a different operating
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	 the patience to stick with Windows through all our mistakes,
	 our buggy drivers, our high TCO, our lack of a sexy version" --
	 Microsoft's C++ Manager Aaron Contorer, in a memo to Bill Gates.