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              *  ATTRIBUTE SET BIB-1 (Z39.50-1995):   *
              *             SEMANTICS                 *
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                           September 1995

2.2  RELATION ATTRIBUTES  (TYPE = 2)

Relation attributes describe the relationship of the access point (left side
of the relation) to the search term as qualified by the attributes (right
side of the relation), e.g., Date-publication <= 1975.


The Relation attributes are the following:

                 Relation                          Value
                 -------------------               ------
                 Less than                           1
                 Less than or equal                  2
                 Equal                               3
                 Greater or equal                    4
                 Greater than                        5
                 Not equal                           6
                 Phonetic                            100
                 Stem                                101
                 Relevance                           102
                 AlwaysMatches                       103


Relation attribute Equal -- specifies an exact match (subject to
possible qualification by the truncation or structure attributes).

Relation attributes Less than, Less than or equal, Greater than or
equal, and Greater than -- meaningful only when both the term value as
qualified by the attributes and the access point can be realized as
elements of a set that has an inherent implied order.

Relation attributes Stem and Phonetic -- Stem refers to a lexical or
linguistic match; the term is to be compared with words in a record to
find those with the same stem.  Phonetic refers to a match based on
aural similarity such as Soundex.  In both cases, the match algorithms
are defined by the target.

Relation attribute Relevance -- used to select records that are
relevant to the term.  When used, the Use attribute determines what
portion of a record is to be evaluated for relevance.  The relevance
algorithm is defined by the target.

Relation attribute AlwaysMatches -- when the Relation attribute
AlwaysMatches occurs:

       - The target ignores the supplied term.
       - If the Use attribute is Any or Anywhere, then all records
           are to be selected.
       - If a Use attribute other than Any or Anywhere is supplied,
           all records are selected for which the access point
           corresponding to the supplied Use attribute is
           meaningful.  For example: if the Use attribute is Title,
           all records that have a title field are selected.