Z39.50 Utility Attribute Set

Draft 1

October 1, 1998

For discussion at the October ZIG meeting.


The Utility attribute set includes values for each of the attribute types defined for Class 1 (as specified by the Z39.50 Attribute Architecture ) that are independent of any particular domain or community, or those that would otherwise need to be defined in several attribute sets.
  1. Abstract

  2. Field Name
    Wildpath may be used for an unanchored search, and wildcard for a single wild card. Thus:
    "field-1 within wildpath" would match "field-1 within field-2 within field-3" but "field-1 within wildcard" would not. "field-1 within wildcard within field-3" would.

  3. Weight
    The weight assigned to the term, for purposes of assigning scores to records. An integer from 0 to 1000.

    May be attached to a term in a request query (submitted by the client in a search request) in which case the supplied value indicates the weight that the client requests be attached to the term.

    May be attached to a term in a response query (returned by the server in a search response) in which case the supplied value indicates the weight that the server attached to the term, or the weight that the server recommends for use in a re-submitted query. When supplied by the server the value may be the same as, or different from, the value in the submitted query. May be supplied by the server even if it was not supplied in the request query.

  4. Hit Count
    May be attached to a term in a returned query in the Search response, and its value is the number of records in which the term occurs. Meaningful only in a returned query, although it may occur in a submitted query but should be ignored by the server. (The server should not infer any semantics based on the occurrence of this attribute, however, nor should the server treat its occurrence as an error, because the client may have simply resubmitted a reformulated query or query otherwise previously returned by the server, where the server included a Hit Count attribute.)

  5. Stopwording
    Presence of this attribute attached to a term in a request query (submitted by the client) indicates that the client requests the server not to treat any words in the term as stopwords. The only meaningful value of this attribute in a request query is 0. (A value of 1 may be supplied in a submitted query but should be ignored by the server. The server should not infer any semantics based on the occurrence of this attribute with a value of 1, however, nor should the server treat its occurrence as an error, because the client may have simply resubmitted a reformulated query or query otherwise previously returned by the server, where the server included this attribute with a value of 1.)

    Presence of this attribute attached to a term in a response query (returned from the server) indicates that the server treated one or more words in the term as stopwords. The only valid value of this attribute in a response query is 1.

  6. Language
    Character string based on RFC 1766 .

  7. Content Authority
    ?

  8. Expansion/Interpretation

  9. Semantic Qualifier

  10. Comparison

  11. Format/structure

  12. Occurrence
    Indicates the desired occurrence of the specified access point. Integer. For example, to indicate second author, the value of the Abstract (or Field Name) attribute is 'author', and the value of the Occurrence attribute is 2.

  13. Indirection