Message-Id: <199602061303.HAA19188@library.wustl.edu> Date: Tue, 6 Feb 1996 07:58:43 -0500 From: "Larry E. Dixson" <mailto:ldix@LOC.GOV> Subject: Re: Search History To: Multiple recipients of list WEBCAT-L <mailto:WEBCAT-L@WUVMD.WUSTL.EDU>
> I would like to clarify the comments made following my original posting:
>
> Z39.50-1995 is commonly referred to as 'version 3' and was ratified
> towards the end of 1995. Most implementors haven't had the time to
> catch up with the new facilities of version 3 yet, though some did
> 'jump the gun' and included some anticipated v3 functionality.
> To quote from the v3 standard:
>
> "'Extended services' is a new facility in Z39.50-1995...Specific extended
> services include: save a result set, set a periodic query schedule,
> export a document, order a document and update a database."
Alan, The "save a result set" in the above quote refers to the persistent result set extended service. This allows an origin to request that a target create a result set that can be saved and referenced during a _subsequent_ search session.
With Version 2, it is possible to assign names to result sets. One can then reference these result sets later within the _same_ search session.
Of course, to be able to take advantage of this using a Web/Z39.50 gateway, the search session must remain open. Hopefully, this will be possible with some of the newer Web gateway Z39.50 clients. Larry
------------------------------------------------------------ Larry E. Dixson Internet: mailto:ldix@loc.gov Network Development and MARC Standards Office, LM639 Library of Congress Telephone: (202) 707-5807 Washington, D.C. 20540-4102 Fax: (202) 707-0115