How to use Boolean operators with a search engine or database?
The Boolean operators (also known as Logical operators) AND, OR, NOT tell search engines/databases which keywords you want your results to include or exclude. You may not know it, but you are doing Boolean searches when you search Google etc. An understanding of how they work will improve your search results
AND
• Between keywords, tells the search engine/database to find articles that include ALL of the words eg education AND primary AND Australia tells the search engine/database to return only those articles/pages that have all three words in them.
• Most search engines/databases eg Google, presume you mean AND if you simply leave a space between your keywords.
NOTE: In EBSCOHost databases if you choose the first search option Boolean/Phrase, you must use the command AND between keywords. In the Gale databases, a space only between the words tells Gale to find the word within 4 words of the other word.
• The more keywords you link with AND or equivalent, the smaller and more defined your search results will become.
OR
• Between keywords, tells the search engine/database to find articles that contain EITHER of the words eg pokies OR slots tells the search engine/database to find articles pages that contain both terms.
• Expands your search.
NOT
• Between keywords, tells the search engine/database to find articles that contain one term, but not pages that contain both terms biting NOT nails retrieves any article/page that mentions nails will not be retrieved.
• In Google, the command is written as: biting –nails
Proximity searching
• Allows you to specify how close you want your terms to appear in the results
• Common commands Near, #, N# (where # is the number of words ie N4 – within 4 words)
NOTE: Available in EBSCOhost and Gale use N# command and Proquest use W/#.
• Google allows you to specify within 2 words eg dog * cat.
• A space between the words in Gale automatically indicates N4 (within 4 words).
Phrasing
• Tells the search engine to only retrieve pages where the words appear next to each other in the exact order
• Useful for quotes, titles, personal names, song lyrics etc.
• Use quotation marks around the phrase you wish to search for eg “Late onset diabetes” .
• In EBSCOhost database, make sure Boolean/Phrase is selected as a search method and just type the phrase with no quotation marks.
Field Searching
• When the search engines retrieves information from web pages, they sort the information into various categories or "fields".
• You can make your search more specific by searching for your terms in those fields only on Google: allintitle:welfare state site:edu.au
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