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The search engine uses a simple query syntax
which gives you the pinpoint search power of Boolean logic, without
having to remember complex queries. The table below shows the search engine
operators that correspond to Boolean operators:
Search
operator |
Boolean
equivalent |
default operator:
you need not use any
special symbols |
OR |
| + |
AND |
| - |
NOT |
phrase operator:
enclose the phrase with
double quotation marks |
ADJ |
Boolean queries use the logical operators AND, OR, NOT and ADJ
(adjacent). Suppose you wanted to find plain paper color laser printers
made by companies other than HP. This query can be specified in Boolean
logic as:
(laser ADJ printer) AND (color OR (plain ADJ paper)) AND
NOT (HP OR Hewlett-Packard)
Using the search engine operators, the complex query above may be typed
into the search box as:
+"laser printer" color "plain paper"
-HP, -Hewlett-Packard
This query specifies that:
- All returned documents must contain the phrase "laser
printer".
- Documents containing one or more of the terms
"laser printer", color, or
"plain paper" will be ranked at the top (the
more terms matched, the higher the ranking).
- None of the documents returned will contain either HP or
Hewlett-Packard.
Statistical Weighting
A traditional Boolean search returns an unsorted list of all items that
match the search condition. The search engine goes considerably beyond this by
using advanced statistical search technology to return the results
sorted with the "best" matches listed at the top. Unlike plain
Boolean searches, the search engine automatically weights your query terms based
on their statistical uniqueness. Common terms, such as
"shall," get a much lower weighting than less frequently
occurring terms, such as the phrase "golf courses."
The search engine's advanced statistical weighting allows you to just type in
relevant words and phrases, and the system will provide the answer to
your query in the top few documents! Since there are cases in which it
is convenient to narrow a query using Boolean operators, the search engine allows
you to use the + and - Boolean operators. With the search engine, you get the
accurate ranking of statistical searching combined with the information
filtering of Boolean searching.
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