SOUTHWEST VIRGINIA COMMUNITY COLLEGE LIBRARY

BOOLEAN LOGIC

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Boolean logic can be used to perform keyword searches.  Use the Boolean logic connectors AND, OR, or NOT to link key words together in a key word search.

AND     

 Use the Boolean connector AND to narrow your search results.  This type of search will result in entries that contain both key words.      
Search example:  homelessness AND children  

OR   

Use the Boolean connector OR to broaden your search results.  This type of search will result in entries that contain either of the key words.         
Search example:  infants OR babies    

NOT      

Use the Boolean connector NOT to exclude unwanted terms in your search results.  This type of search will result in entries that contain the desired key word but will exclude entries that include both the desired and undesired key terms together.     
Search example:  penguin NOT Pittsburgh    

Multiple Boolean connectors can be used in the same search statement.  If you use multiple Boolean connectors and include an OR in the same search statement, you must "nest" the OR terms with parentheses.
For example, use the search statement  (preg* OR prenatal) AND exercise  to find information on the benefits of exercise during pregnancy.

Truncation

Truncation was used in the search example above. Truncation involves the use of a symbol to cut off the indefinite end of a word stem.  It is a method of retrieving various forms of words sharing common roots or stems.  Truncation may be used at the end of a stem (skat*) or beginning (*ology) or internally (wom?n).

For example, violen* will produce the following results: violence, violent, violently.

Use an * to truncate in the SWCC Online Catalog, EBSCOhost, InfoTrac, FirstSearch, or when using most Internet search engines.
Use "quotation marks" around phrases to keep words side-by-side in search results.