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* ATTRIBUTE SET BIB-1 (Z39.50-1995): *
* SEMANTICS *
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September 1995
2.4 STRUCTURE ATTRIBUTES (TYPE = 4)
The Structure attribute specifies the type of search term (e.g., a single
word, a phrase, several words to be treated as multiple single terms, etc.).
The Structure attributes are the following:
Structure Value Definition
--------------- ----- -------------------------------------------
Phrase 1 A phrase consists of one or more groups of
characters separated by blanks (for example,
ASCII hex "20"). The value to be searched
is exactly as it appears in the search term
with respect to order and adjacency. Word(s)
in the phrase may be explicitly truncated.
(See "Truncation" -- section 2.5 below.) To
indicate that additional words may appear in
the access point, use the completeness
attribute.
Word 2 A word consists of a group of non-blank
characters. It specifies the exact text of
the value to be searched, unless the word is
explicitly truncated. (See "Truncation" --
section 2.5 below.) A word search term
contains no blanks.
Key 3 A key specifies a sequence of characters
extracted from those characters contained
in an indexed word but not necessarily
representing complete words. In the term,
key segments should be separated by a
blank (ASCII hex "20"). Each key segment
should be the length of a key segment in
the origin system or the length of the
word, to a maximum of 6 characters. (For
example, an name/title derived key search
term for "Copland, Aaron, 1900- Rodeo"
could be "coplan rodeo".) A segment may
be adjusted by the target to the length
required for the target's indexes. For
example, the following derived key
searches are in use at LC and at OCLC (in
Online System):
Site Index Letters taken Source Data
----- ---------- ------------- --------------
OCLC TITLE 3,2,2,1 title keywords
NAME/TITLE 4,4 name, title
NAME 4,3,1 personal name
CNAME 4,3,1 corporate name
LC PTK 3,1,1,1 title keywords
PATK 3,3 name, title
PPNK 5,1 or 6 personal name
Year 4 A year search term is numeric and contains
four digits.
Date 5 The day, month, year and time when a
(normalized) transaction or event takes place. The
date search term structure is as defined
for Generalized Time in ASN.1 (ISO 8824)
except that the only mandatory portion of
the string is the four-digit representation
of the year.
Word list 6 A word list consists of one or more words
separated by blanks (for example, ASCII
hex "20"). No order of the words is
implied. The attributes (other than
structure) that are associated with the
search term apply to each word in the
word list. Any words in a word list may
be explicitly truncated. (See
"Truncation" -- section 2.5 below.) The
relationship between the words in a word list
is target-specific.
Date 100 The day, month, and year when a transaction or
(un-normalized) event takes place. The un-normalized search
term is unstructured.
Name 101 A name search term that is structured in a
(normalized) particular order (e.g., last_name,
first_name). The resulting term is subject to
special matching rules on the target system
that differ from those applied to names
structured as phrases or unstructured names.
Name 102 A name search term that is unstructured (e.g.,
(un-normalized) first_name last_name), however, the resulting
term is subject to matching rules on the
target system that differ from those applied
to phrases or structured names (e.g.,
the term "john smith" might be searched
by the target as "smith, j#").
Structure 103 The term has a structure that is either
implied by the Use attribute or
defined by the target.
Urx 104 The term is a document identifier, for
example, an identifier extracted from a
Z39.50 URL.
Free-form-text 105 The term is text, input by the end user.
May be used, for example, for relevance
feedback.
Document-text 106 The term is text, extracted from a document.
May be used, for example, for relevance
feedback.
Local-number 107 A number significant to the target.
String 108 The entire term is to be treated as a string,
rather than a sequence or set of individual
words.
Numeric string 109 The term is a character string that represents
a number.