HP Software Reference Information Storage System v1.6 User Guide (T3559-90810, November 2008)
3 Q uery expression syn tax and
matc hing
Query expression syntax and matching describes the RISS Web Interface syntax to use to search and
retrieve archived documents (filesoremailmessages),andexplainshowqueriesarematchedagainst
documents.
Major topics include:
•
Query expressions, page 37
•
Word characters ,page37
•
Letters and digits in different character sets , page 38
•
Matching words, page 39
•
Matching similar words,page39
•
Matching word sequences, page 40
•
Boolean query expressions, page 43
•
Nested Boolean query expressions,page43
• Quer y expression examples,page44
Query exp
ressions
Query expressions can be as simple or as complex as needed. The essential idea behind document
retrieval is that query words are compared with document words to fi nd a match. You can also:
• Look for
document words that are textually similar, but not necessarily identical, to query words.
See “Matching similar word s” on page 39.
• Look for word sequences in a document: words that are near each other, and in a particular
ord er.
See “Matching word sequences”onpage40.
• Combine quer y words using logical (Boolean) operators (AND, OR, NOT). See
“Boolean query expressions”onpage43.
Together, these query constructs provide considerable power to find what you need, provided you
learn
to use them well.
The way query expressions are interpreted is similar to the way documents are indexed when archived.
Text is parsed (broken down) into words. Remaining characters are considered separators and ignored.
Quer y expressions are fundamentally composed of words, no m atter how complex the expression.
For in
dexing and searching, a word need not belong to a natural language, such as English. For
example, wt6_ht3 is a valid document word or query word. Qu ery words can contain wildcards,
such as in f??t.
Word characters
When the system examines a quer y expression to determine its words, some characters a re not included
in query words, but are treated as word separators. When a document is archived, indexing determines
which document words are available for searching in the same way.
Learning the rules of creating query words means also learning the rules of document indexing and,
therefore, what words you can search for.
User Guide
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