The ZeeRex Context Set for CQL, version 2.0

23rd February 2005

The indexes provided by the ZeeRex context set are intended to be used with indexes from other sets to implement The ZeeRex Profile for SRW/U. This document describes version 2.0 of the ZeeRex context set.

Version 2.0 of the ZeeRex Context Set is uniquely identified by the URI

The conventional prefix for use with the ZeeRex Context Set is zeerex. Therefore, ZeeRex queries may begin with the following CQL prefix-mapping:


The ZeeRex Context Set contains the indexes listed in the following table:

Name Description
explainAdmin Searches against this ``special'' access point must be for one of the following set of special terms:
Finds all and only the ZeeRex records which describe databases on the server being searched.
Finds only authoritative records; that is, those for which the authoritative attribute is set.
databaseName The search terms should be the name of a database; the search is for all records which include information about a database with that name.
recordSyntax The search term should be the symbolic name or dot-separated OID of a record syntax; the search is for all records representing databases capable of supplying records in that record syntax.

As with host names, although there is a choice in how the search term is represented - either as a symbolic name (e.g. USMARC) or as an OID (e.g. 1.2.840.10003.5.10) - each case will find only servers which are specified as being able to supply the record syntax in the specified form: for example, a search for USMARC will not find a record which only specifies a record syntax of 1.2.840.10003.5.10.

attribute Finds databases which have a map that supports searching with the specified attribute. ``Attributes'' in this sense may be either index names (for databases supporting SRW/U) or attributes in the classic sense (for databases supporting Z39.50).

An attributes in the former, SRW/U sense, is specified by a combination of the identifying URL of the context set that provides it, and the index-name iself. These two elements are glued together into a single search term of the form context-set-URI:index-name. Since the context-set URI may contain a colon but the index name cannot, servers are advised to parse these search-terms backwards, starting at the end. For example, info:srw/cql-context-set/1/dc-v1.1:title searches for the Dublin Core context set's ``title'' index.

Attributes in the latter, Z39.50, sense are specified by a combination of attribute set, attribute type and attribute value. These three elements are glued together into a single search term of the form attributeSet:type=value, where the attribute set is expressed as in the attributeSet attribute in the DTD, the type is a number and the value may be a number or a string. For example, BIB-1:1=21 searches for the BIB-1 attribute set's ``subject'' access point.

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