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Advanced search techniques - boolean, truncation, and wildcards

Search more effectively and get better results by using some of these techniques.

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Boolean operators and truncation

Boolean Searching is a database search method based on the principles of Boolean logic, originally developed by the British mathematician George Boole in the mid 19th century. Boolean searching allows you to combine search terms in specific ways for effective matches.

OPERATOR

EXAMPLE

EXPLANATION

AND

Document must have both words (or both phrases)
copyright AND moral rights Will narrow your search because search results will include all documents that contain both the first term and the second term.
OR

Document can have either word (or either phrase)

tobacco OR cigarettes Will expand your search because search results will include all documents that contain either the first term or the second term or both.
NOT

Document must have first term. Must not have second

* use very carefully because may exclude lots of useful information.

love NOT war Will exclude an idea/concept from your search because it will find documents that contain the first word, but do not contain the second.

NOT is helpful if you notice a recurring topic in your retrieval that is not relevant to your topic.
ADJ

Forces the computer to search for words in a specified order.

obsessive adj compulsive Will find results where obsessive immediately precedes compulsive
NEAR

Retrieves items that have both terms in the same sentence. You can add a number to near to instruct the computer to find results within those numbers of words in any order
alcohol near abuse

alcohol near3 abuse.
This will retrieve results where alcohol is within 3 words of abuse.

i.e., "Men who abuse their wives after alcohol consumption” or “Alcohol consumption leads to abuse"

Boolean Strategies

- If you are retrieving too many records on your topic, try adding another search term with the connector AND.

- If you are retrieving too few records on your topic, try adding another search term with the connector OR.·       

- If you are retrieving too many records on an unrelated topic, try eliminating a word with the connector NOT.

Truncation & Wildcards

To increase the number of hits retrieved, you might consider using a truncation symbol.  Truncation will pick up variations of a word stem. Truncation symbols vary, depending on the database.


e.g., critic* will find critic, critics, criticism, critical, etc.


The wildcard symbol can be used to replace one letter in a word. This will instruct the computer to do a search and match all letters in the word and use any letter to replace the wildcard symbol.


e.g., Wom?n will retrieve records with woman and women.


VERY IMPORTANT:The TRU library catalogue uses “$”, but all of the article databases use “*” for their truncation and wildcard symbols.