Boolean Searching (or why am I getting articles about the myriad uses of giraffe hair?) Sullivan Library

Boolean searching Boolean searching is a technique supported by most library catalogs, periodical databases, and search engines. Boolean utilizes AND, OR and NOT to facilitate subject and keyword searches. In effect, it broadens and narrows search results and improves the retrieval of relevant search results. The following four (4) slides use Venn diagrams to illustrate Boolean searches.

Boolean searching cats AND dogs catsdogs AND AND: Shaded area is all items which contain both ‘cats’ and ‘dogs’. This narrows your search.

Boolean searching dolphinsporpoises OR OR: Shaded area is items which contain either ‘porpoises’ or ‘dolphins’ or a combination of both. This broadens your search. To remember this, you can think of the phrase, “more with ‘or’”.

Boolean searching porpoises NOT gambling dolphins lottery Miami NOT: Filters out unwanted terms (shaded area represents the desired topic). For example, you can search ‘dolphins not Miami’ to avoid articles about the Miami Dolphins football team.

Boolean searching (schools OR repairs) NOT fish schoolsrepairs fish Search terms can be combined, like a math equation: (x+y)=z. If you need “schools or repairs”, but want to avoid “schools of fish”, you can combine Boolean terms to improve relevant searches while filtering out unwanted results.

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